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Albany Clear Sky Clock

Skywatch Line scripts are written by members of the Albany Area Amateur Astronomers. They can be heard by calling 518-382-7890 ext. 229. Scripts are copyrighted and may not be reproduced without permission.

Call 518-382-7890 extension 229 to hear the current Skywatch Line

This is Dudley Observatory’s Skywatch Line for Friday, October 17, through Sunday, October 19, written by Alan French.

The Moon reached last quarter this past Wednesday and is now moving toward new, so a waning crescent Moon rises after midnight this weekend leaving the evening sky dark and moonless.

Most serious star gazers eventually buy a telescope, but you don’t need a telescope to enjoy the night sky. There is much to be seen without a telescope, and some sights are actually best seen by eye. At 7:00 pm on Friday, October 17, this writer will give a talk on “Enjoying and Exploring the Night Sky,” which will focus on sights that can be enjoyed by eye alone. It will be held at the Octagon Barn in Knox. (For directions, use 588 Middle Road, Delanson, NY 12053.) The Octagon Barn is on the south side of Middle Road just west of the intersection of Beebe Road.

Weather permitting, there will be a star party following the talk, giving guests a chance to enjoy various celestial sights through a number of telescopes. Telescopes will be provided by Dudley Observatory and the Albany Area Amateur Astronomers. I hope to see you there!

If the skies are clear, the Albany Area Amateur Astronomer will also hold a public star party in the Deerfield Pavilion area of Grafton Lakes State Park at 7:30 pm on Friday, October 17. At star parties a variety of telescopes are set up to show guests celestial sights, including star clusters, nebulae, galaxies, and double stars. If the skies are cloudy Friday night, it will be rescheduled for Saturday, October 18 – if the skies cooperate.

If you look toward the northeast around 8:00 pm you should easily spot a conspicuous “W”: of bright stars, with the bottom of the “W” approximately to your right. These are the brightest stars of Cassiopeia, the Queen. In old star atlases, which artistically depicted the constellations, she was usually shown sitting in her chair, often formed by the stars of the “W.”

Cassiopeia was the wife of King Cepheus, the ruler of Ethiopia. He also has a constellation, which now rides high in the sky at 8:00 pm, appearing above and to the right of Polaris, the North Star.

The Milky Way runs through Cassiopeia and the region is rich with stars and clusters of stars. Exploring the area under dark skies with binoculars from the comfort of a reclining lawn chair can be a lot of fun and there is a lot to see through even a small telescope.

The Dudley Observatory Skywatch Line for Wednesday, October 15th and Thursday, October 16th written by Louis Suarato.

The Last Quarter Moon sets around 2 p.m. EDT Wednesday, leaving the skies darker for night observing. Saturn sets at 7:35 p.m. during Nautical Twilight, when the Sun is 12 degrees below the horizon. At that time, Mars will be 11 degrees above the southwestern horizon. If you have a clear view of southwestern horizon, you’ll have about an hour to search for Comet Siding Spring before Mars sets. Look for Comet Siding Spring with binoculars or telescope 4 degrees to the south, or left of Mars. Comet Siding Spring makes its closest approach to the red planet on October 19th at a distance of 88,000 miles. Keep an eye out for images of the comet on the NASA website dedicated to this event http://mars.nasa.gov/comets/sidingspring/. October 15 is the birth date of Asaph Hall. Born in 1829, Hall discovered and named the two moons of Mars, Phobos and Deimos.

While Mars is setting, the Big Dipper asterism, in the constellation Ursa Major, is almost parallel to the horizon, low in the northwest. Above Ursa Major, curling around Polaris in Ursa Minor to the west, is the constellation Draco. About 10 degrees above the Little Dipper’s bucket, where the stars of Draco begin to turn upward, is the dwarf spiral galaxy NGC 6503. Although this galaxy was discovered with a 2.6 refractor, it is better viewed using a larger telescope. About 3.6 degrees southeast of NGC 6503 is NGC 6543, the Cat’s Eye planetary nebula, or Caldwell 6. A planetary nebula is formed from the ejected cloud of ionized gas from an aged star. Look for its blue-green color and central star.

Moonrise occurs just after midnight followed by Jupiter at 1:40 a.m. on Thursday. Jupiter will be 5 degrees north of the Moon after midnight Friday.

This week’s local astronomy events include Dudley Observatory’s Octagonal Barn Star Party on Friday, October 17th. Beginning at 7 p.m., Alan French will discuss "Exploring and Enjoying the Night Sky". Alan will discuss how some of the best night sky objects and events can be enjoyed without the use of a telescope. Alan will also include an introduction to binocular astronomy.

Also on Friday, the Albany Area Amateur Astronomers will be hosting a star party at Grafton Lakes State Park. Directions can be found at http://www.dudleyobservatory.org/AAAA/Directions.html.


This is the Dudley Observatory Skywatch Line for Monday and Tuesday, October 13th and 14th written by Joe Slomka.

The Sun sets at 6:16 PM; night falls at 7:50. Dawn breaks at 5:33 AM and ends with the Sun rising at 7:07.

As the sky darkens, the only bright planets visible are Saturn and Mars. Saturn is low in the Southwest. Observers should get their last looks in now, since it sets just before nightfall. The low altitude means that Earth’s turbulent atmosphere will blur the usually magnificent view of the planet and its rings.

Mars is the other bright planet. The Red Planet is currently located in Ophiuchus, above the Scorpion’s stinger. Mars is a disappointing planet now, since it appears as a tiny ball in most backyard telescopes. Mars sets at 9:08 PM.

At nightfall, planets Neptune and Uranus become visible. Neptune is a seventh magnitude blue-green dot in Aquarius, while Uranus is brighter and slightly larger in Pisces. Astronomy media have finder charts to these distant members of the Solar System.

The constellation Perseus is well up at twilight’s end. The bright star Algol, in Perseus’ shorter leg, undergoes its periodic darkening at 7:59 PM, Monday. An unseen body eclipses Algol every 2.87 days.

Comet Jacques is still in our night sky as an eleventh magnitude fuzz ball four-and-a-half degrees West of Delta Aquilae. Amateurs with large telescopes may still be able to see this cosmic visitor.

The waning Moon rises after 10 PM on Monday, and after 11 PM on Tuesday. It appears between Orion’s club on Monday, and by Pollux’s knee on Tuesday. It officially becomes Last Quarter on Wednesday afternoon.

Jupiter rises about 1:40 AM and is found midway between Leo and Cancer. Telescopic observers can see the Great Red Spot, a giant storm, on Jupiter at 2:15 AM, Tuesday;Wednesday at 3:43 AM, they can see Jupiter’s moon Io’s shadow begin to cross the planet’s face, followed by the moon itself at 4:50.

Monday is Columbus Day. Most people are familiar with the story of Columbus sailing west to reach China. When he landed in the Caribbean, he thought he had found Japan. How could he have made that mistake? Finding latitude is easy, sight on the Pole Star and measure its height above the horizon. But longitude could not be calculated without very accurate sea-borne clocks; such clocks were not invented for another 200 years. Two ancient Greeks measured the Earth. Eratosthenes accurately estimated the Earth's diameter; Claudius Ptolemy underestimated it. Arab scholars provided other approximations of Earth’s size. They used a smaller Arabic mile, which Columbus mistook to be equal to nautical miles. Using "dead reckoning," a navigational estimation of a ship's course, it was natural for Columbus to mistake the island of Jamaica for Japan.

This is Dudley Observatory’s Skywatch Line for Friday, October 10, through Sunday, October 12, written by Alan French.

The Moon was full early this past Wednesday, so a waning gibbous Moon will dominate the weekend’s night sky. It will reach last quarter next Wednesday.

This weekend features a chance to see the bright reddish star Aldebaran, marking the eye of Taurus, the Bull, close to the Moon. If you’re not a morning person, look for the pair Saturday night.

The Moon rises at 8:41 pm Saturday. By 10 pm the Moon, just over twelve degrees above the eastern horizon, will be a little over two degrees from Aldebaran, which will be to the Moon’s lower left. The distance will gradually shrink through the night as the Moon moves eastward among the stars. If you can, be sure to check out the area around with Moon with binoculars and enjoy the lovely stars of the Hyades, a large, loose, cluster, whose brighter members outline the face of Taurus, the Bull.

If you are a morning person and are up before the Sun on Sunday morning you’ll get the see the Moon even closer to Aldebaran in the southwestern sky. At 6:00 am Aldebaran will be less than one degree to the lower left of the Moon.

We’re in a period of transition. The stars of summer are gradually moving lower into the Sun’s glow in the west, and the stars of winter are rising earlier each night. By 10:00 pm bright Capella dominates the northeastern sky.

Capella is the sixth brightest star in the night sky, only slightly exceeded by Vega, which we wrote about last weekend. Lying 42 light years from Earth Capella is also bright because it is in our neighborhood. It is the first magnitude star closest to Polaris.

Capella is the brightest star in Auriga, the Charioteer. Look for a nice pentagon of stars below and largely to the right of Capella at 10:00 pm. These outline Auriga. The Charioteer was responsible for the King’s livestock, and star atlases often depict the figure holding young goats or kids. The small triangle of stars near Capella is called “The Kids.”

Watch during the coming weeks as Capella and Auriga move higher in the sky each evening. The stars travel across the sky because the Earth rotates on its axis once every 24 hours, but the Earth is also traveling around the Sun. This causes the stars to rise about four minutes earlier each night. This may not seem like a big difference, but it is almost 30 minutes in a week and two hours in a month. If we have a long cloudy spell, the change in the sky can be more obvious than usual.

The Dudley Observatory Skywatch Line for Wednesday, October 8th and Thursday, October 9th written by Louis Suarato.



Saturn is on its farewell tour as it appears lower and lower on the horizon each evening after sunset. Look for Saturn less than 10 degrees over the west-southwestern horizon after 7 p.m. EDT. You’ll find Scorpius’ brightest star, Antares, setting 20 degrees to the south of Saturn. Mars shines at magnitude 1.01, at approximately 8 degrees to Antares’ upper left. Mars welcomed two new visitors recently. NASA’s MAVEN (Mars Atmosphere and Volatile Evolution Mission) entered the red planet’s orbit on September 21st. India’s MOM (Mars Orbiter Mission) began orbiting Mars on September 24th. Both spacecraft arrived just in time to attempt to obtain a good view of Comet Sliding Spring as it passes just 82,000 miles above Mars’ atmosphere on October 19th. Comet Siding Spring’s will pass 16 times closer to Mars than any known comet has sailed by Earth. The closest known comet to Earth was Lexell’s Comet in 1770 at 1.4 million miles. NASA’s Mars Reconnaissance Orbiter, Mars Odyssey, Curiosity, and Opportunity also have planned science observations of the comet as its 12,000 mile coma and tail sweep past the planet. Viewed from Earth, Comet Siding Spring is currently at magnitude 8.23, and will become slightly dimmer as it approaches Mars and can be seen with small telescopes or binoculars under dark skies.

The Full Hunter’s Moon rises in Pisces at 6:37 p.m. Wednesday evening, 13 minutes after sunset. Look for four bright craters during the full phase of the Moon. Aristarchus, at 25 miles across, is the brightest feature on the Earth-facing side of the Moon. Not far from the crater Aristarchus are the craters Copernicus, at 56 miles across, and Kepler, at 20 miles wide. Tycho, with its widespread rays from impact, is the most impressive and is at 53 miles in diameter. Uranus can be found 6 degrees to the lower left of the Full Moon but may be difficult to see in the Moon’s bright glow. Jupiter rises at 2 a.m. Thursday in the constellation Cancer.

There will be very bright International Space Station passes over our region Wednesday and Thursday nights. Wednesday, the ISS will emerge out of the west-northwestern horizon at 7:46 pm., and fly through the constellation Cygnus before disappearing in Earth’s shadow between Andromeda and Cassiopeia at 7:50. Thursday, look to the southwest at 6:57 pm as the ISS flys by Mars, through Pegusus, and continues northeast.

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, October Sixth and Seventh written by Joe Slomka.

The Sun sets at 6:28 PM; night falls at 8:02. Dawn breaks at 5:25 AM and ends with the Sun rising at 6:59.

The darkening sky is bathed by the light of a nearly Full Moon on both nights, rendering planets Uranus and Neptune, as well as most deep sky objects, unobservable. The Moon becomes the “Full Hunter Moon” Wednesday morning and also undergoes a total Lunar Eclipse. More about the eclipse in a minute.

Two bright planets withstand the Moon’s brilliance: Mars and Saturn. Mars appears moderately low in the South, six degrees above the like tinted star Antares. Mars continues its travels eastward; in an amateur telescope, Mars appears as a small, featureless red ball. Saturn, on the other hand, is a spectacular sight in almost any telescope. An observer should look for Saturn as soon as possible, since it is so low and sets at 8:11 PM. Mars sets three hours after sunrise all this month.

Jupiter rises at 2:04 AM and, by Dawn, is high enough for examination of the planet and its many moons. On Tuesday morning at 3:16, the moon Ganymede reappears from behind Jupiter’s shadow; at 4:01, the moon itself disappears behind Jupiter. At 4:28, the moon Io disappears into Jupiter’s shadow.

As previously mentioned, the Moon experiences a total eclipse on Wednesday morning. All of North America can witness it, but the West Coast and Pacific islands have the best view – they enjoy the whole event. Totality lasts fifty-nine minutes; but, for the Capital District, the Moon sets during totality. This is the second of four total lunar eclipses – a tetrad. The next eclipses take place a half-year apart during April and September 2015; all will be seen by North America.

Total lunar eclipses occur when the Moon moves into Earth’s shadow. The Earth, between the Moon and Sun, casts its shadow as two cones, one darker than the other. The paler is called the “penumbra;” the darker is the “umbra.” During this eclipse, the shadows hit the lunar surface slightly off center. The result is the southern half of the Moon appears darker than the northern half.

There are three stages to a lunar eclipse. The first is the penumbral phase. It is normally difficult for first timers to notice the very subtle ingress of the faint portion of Earth’s shadow until it is more than halfway across the Moon. The second, partial eclipse, stage happens when the darkest portion of Earth’s shadow begins to transit the lunar face. Total eclipse is the third phase; the whole Moon is enveloped by Earth’s shadow. At this time, the Moon takes on a reddish glow. The Sun’s light is bent by Earth’s atmosphere and illuminates the lunar surface. The shadow’s color depends on how polluted is Earth’s atmosphere. The Moon can appear a light red to totally black. Wednesday, during Totality, viewers can see normally dim Uranus only one degree from the Moon.

Once Earth’s shadow covers the Moon, the phases reverse from total to partial and then penumbral. However, we will not view that because the Moon sets during totality. If the spectator is lucky enough to have unobstructed eastern and western horizons, he can see both the setting Moon in the West and the rising Sun in the East. This rare event is called a Selenelion.

If you missed the eclipse for any reason, there will be a partial Solar Eclipse on the afternoon of October 23.


This is Dudley Observatory’s Skywatch Line for Friday, October 3, through Sunday, October 5, written by Alan French.

The Moon reached first quarter last Wednesday, so a waxing gibbous Moon will dominate the evening sky over the weekend. The Moon reaches full early this coming Wednesday, and we’ll be treated to a total lunar eclipse during the hours before sunrise. From here, the Moon will set while totally eclipsed.

If you look high in the sky, almost directly overhead, around 8:00 pm you’ll spot a bright star. This is Vega, the fifth brightest star in the night sky. Like most of the brighter stars, it is bright because it is one of our closer neighbors, lying at a distance of 25 light years. The light you see left Vega in 1989.

Because of its prominence and placement high in the sky, Vega was the subject of two firsts. It had its portrait taken with the 15-inch “Great Refractor” at Harvard Observatory in 1850, becoming the first star, other than our Sun, photographed. It was also the first star to have its spectrum photographed, work that was done by Henry Draper in 1872.

Vega was the North Star about 14,000 years ago and will again be the North Star in around 12,000 years. Polaris, our current North Star, is closer to the North Celestial Pole, the exact point in the sky the Earth’s north axis points to, and makes a fainter but more accurate indicator of true north. Actually, in the 26,000 years it takes the Earth’s axis to trace a complete circle in the sky, it is unusual to have a star as bright as Polaris, which shines at second magnitude, so close to true north.

Vega is the brightest star in the small constellation of Lyra, the Lyre. (Lyra ranks fifty-second in size out of the eight-eight constellations.) The shape of this small constellation is distinctive and easy to recognize. First look for a parallelogram of stars of about equal brightness to the southeast of Vega. Then look for a lone star to its northeast. This small obvious pattern of stars, along with Vega, forms Lyra.

Midway between the two stars farthest from Vega is a popular object for amateur astronomers, the Ring Nebula. It is a planetary nebula, an expanding cloud of ionized gas ejected from a red giant star in its old age. The Ring Nebula is often referred to as M57, the fifty-seventh object on comet hunter Charles Messier’s list of 110 deep sky objects. Messier’s objects are popular targets for telescopes.

The lone star to Vega’s northeast is also a frequent sight in amateur telescopes. It is the famous “Double-Double,” a pair of double stars. The pairs are fairly widely separated and easy to discern, but the members of each pair are closer and more of a challenge. On a steady night, where star images are little disturbed by the light’s passage through our atmosphere, the Double-Double is a lovely sight through a fine telescope.

The Dudley Observatory Skywatch Line for Wednesday, October 1st and Thursday, October 2nd written by Louis Suarato.

The Moon reaches its First Quarter phase at 3:33 p.m. EDT on Wednesday. Look for the First Quarter Moon above the Teapot asterism in Sagittarius in the south after sunset. Brian McCurdy writes “Among the major satellites of the Solar System, only the Moon and Neptune’s Triton do not orbit in the plane of the equator of its planet. The Moon roughly orbits in the plane of the ecliptic, causing it to ride high or low at different points in the month, and at different phases throughout the calendar year. For example, a first-quarter Moon always cruises high in the sky around the time of the spring equinox but low around the autumn equinox.”

Visible lunar features during this phase include the craters Hipparchus and Albategnius. Both craters can be found on the terminator. Hipparchus is closest to the equator, with Albategnius below. Hipparchus is a crater created by an impact billions of years ago and since flooded by lava. Inside of Hipparchus is another crater, Horrocks, created by a later impact. Horrocks can be found on the northeast rim of Hipparchus. Hipparchus is 93 miles in diameter and 2 miles deep. Albategnius, also lava flooded, is 80 miles in diameter and is 2.5 miles deep. Another popular feature to view during this phase is the Lunar Straight Wall or Rupes Recta. At 800 to 1,000 feet, this lunar escarpment is about as high as our own Helderberg Escarpment and 68 miles long. The Lunar Straight Wall can be found to the lower left of the trio of large craters, Ptolemaeus, Alphonsus, and Arzachal, at the center of the terminator.

Catch Saturn low on the southwest horizon before it sets. Mars is to the south, 4 degrees above red supergiant, Anatares. To the east, the Pleiades star cluster rises in Taurus around 9 pm. For those wanting to see Orion again, look to the east after midnight. Jupiter rises around 3 am between the Beehive Cluster, or M44, in Cancer and Leo’s brightest star Regulus. Jupiter’s magnitude will increase from -1.9 to -2.1 during October.

This is the Dudley Observatory Skywatch Line for Monday, September 29th and Tuesday, September 30th written by Joe Slomka.

The Sun sets at 6:40 PM; night falls at 8:14. Dawn breaks at 5:17 AM and ends with sunrise at 6:51.

As the sky darkens, bright Saturn and slightly dimmer Mars are the only visible planets in the sky. Saturn is furthest and brightest in the southwest. Saturn is moderately low, so observers should get their telescopes ready at sunset. The thick atmosphere near the horizon will now hinder views of the ringed planet and its satellites. Saturn sets at 8:37 PM.

Mars appears almost due South in Scorpius. The Red Planet lies three degrees above the brightest star in the constellation – Antares. From classical times, these two were considered “rivals.” Use your binoculars or telescopes to compare their colors. This is the closest Mars will be to Antares this month; Mars will continue its relentless trek eastward. Mars is a very busy planet these months. Besides two US spacecraft orbiting it and two rovers surveying its surface, NASA just inserted a third orbiter – MAVEN, which will study the Martian atmosphere and where its water went. India’s orbiter, the Mars Orbiter Mission (MOM) also just reached Mars. MOM is less sophisticated and cheaper than NASA’s, but it has a camera, instruments to detect deuterium and methane, as well a determining the composition of the Martian atmosphere and surface. Next month MAVEN will be distracted by a visitor – Comet Siding Spring. The comet will come within 82,000 miles from Mars. NASA will maneuver its orbiters to avoid comet debris. But MAVEN’s ultraviolet spectrometer will study the composition of the comet’s atmosphere and tail.

The five-day-old Moon hovers five degrees above Mars on Monday; Tuesday sees a fatter Moon in Sagittarius. The Moon sets at 10:05 PM, Monday; Tuesday, it sets at 11 PM.

Nightfall finds Neptune still in Aquarius and Uranus in Pisces. Astronomy magazines, websites and apps provide observing charts.

Comet Jacques remains at tenth magnitude in the constellation Aquila. The brightening Moon may make observation difficult. Comet Jacques lies about ten degrees West of Altair and about three degrees south of Zeta Aquilae.

Jupiter rises at 2:26 AM in Cancer. Jupiter is great in both binoculars and telescopes. The four moons that Galileo discovered are readily seen by both instruments. At 3:34 AM on Tuesday, Ganymede reappears from behind the planet; at 5:53 AM, Europa also reappears. At 3:13 AM on Wednesday, Io finishes its transit across Jupiter’s face.

Venus blazes low on the eastern horizon before Sunrise. Venus is ending its appearance and appears slightly lower each day. An observer should have an unobstructed horizon, since Venus is only about one degree above the horizon.

This is Dudley Observatory’s Skywatch Line for Friday, September 26, through Sunday, September 28, written by Alan French.

Weather permitting; the Albany Area Amateur Astronomers hold public star parties at Landis Arboretum in Esperance at 8:00 pm on Friday, September 26, and Saturday, September 27. This is a lovely time of year for star gazing. The temperatures are still reasonable, the biting insects are gone, and it gets dark at a reasonable hour. (Although temperatures are not terribly low, it is easy to get chilled when inactive under the clear night sky, so extra clothing and a warm winter hat are recommended.)

At a star party amateur astronomers set up telescopes to provide guests with views of celestial sights, including star clusters, nebulae, galaxies, and double stars. There will be a short introductory program starting about 8:15 pm in front of the meeting house. It will include hints for getting the best telescopic views and a short tour of the prominent constellations.

These star parties will be held in the Meeting House field at Landis Arboretum. You can find directions to Landis here. Once you see the farm house on your right and a parking area on you left, continue up Lape Road about 100 feet. Turn into the Meeting House driveway on your right.

Star parties are open to all and there is no admission fee, although we do encourage guests to make a donation to our fine hosts, Landis Arboretum. A donation box is next to the south door on the Meeting House.

If you’re up early on Monday there is a fine pass of the International Space Station visible in the pre-dawn skies. The ISS will first appear just after 5:38 am moving out of the Earth’s shadow when 23 degrees above the west northwestern horizon. It will be highest at 5:40 am when 71 degrees above the southwest horizon – appearing essentially overhead – and will disappear in the southeast at 5:43:25 am.

The space station will first appear near the lower right (northern) corner of the Great Square of Pegasus, will move up the side of the square, then past Perseus, between Auriga and Taurus, and above Orion. As I write three astronauts are on the ISS, with three more on the way aboard a Soyuz spacecraft. By the time you see the ISS, all six astronauts should be on board.

The Dudley Observatory Skywatch Line for Wednesday, September 24th and Thursday, September 25th written by Louis Suarato.

The New Moon takes place at 2:15 a.m. EDT on Wednesday. The New Moon is the first phase of the Moon and begins the waxing phases until the Moon is full. The New Moon phase is the instant the Moon is between the Earth and Sun and the illuminated side of the Moon is opposite Earth. When this alignment is exact from your viewing area, a solar eclipse occurs. There will be a partial solar eclipse over our region on October 23rd beginning at 5:45 p.m. EDT. Unfortunately for our area, the Sun will set before the eclipse is at its maximum.

The Autumn night sky is dominated by the constellation Pegusus. Look over the eastern horizon after sunset for the Great Square of Pegusus, the most evident feature of this constellation. The two lower stars of the Great Square point to the globular cluster, M15, at the southern end of the constellation, or 4 degrees to the northwest of the 2nd magnitude star Enif (Epsilon Pegasi). Epsilon Pegasi is the brightest star in Pegusus. M15’s core is one of the densest of the globular clusters, filled with massive neutron stars. At an estimated age of 12 billion years old, M15 is one of the oldest globular clusters. M15 contains approximately 100,000 stars and is 33,600 light years from Earth. This globular cluster has a magnitude of 6.2, and can be seen with the naked eye under extremely dark skies, but is better viewed through binoculars or telescopes.

With Mercury and Venus lost in the glow of the Sun, Mars, Saturn and Jupiter are your best bets to view naked eye visible planets. Look for Mars and Saturn as they set in the southwest after sunset. Scorpius’ brightest star, Antares, will complement Mars’ red color, just 4 degrees to its left. Jupiter rises in the constellation Cancer just after 3am Thursday.

The Albany Area Amateur Astronomers will be hosting Star Parties, weather permitting, this Friday and Saturday nights at the Landis Arboretum in Esperance, NY. Telescopic views of the various celestial bodies, including galaxies, star clusters, nebulae, and binary stars, will be available to our guests. You are welcome to bring a telescope if you have one and the club members will be happy to answer any questions about operating a telescope you’ve purchased, or are thinking of purchasing. Star Parties provide a great opportunity to “test drive” various types of telescopes. Direction to the Landis Arboretum can be found at http://www.dudleyobservatory.org/AAAA/General.html.

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, September 22nd and 23rd written by Joe Slomka.

The Sun sets at 6:52 PM; night falls at 8:27. Dawn breaks at 5:08 AM and ends with the Sun rising at 6:43.

As the sky darkens, three bright planets appear in the western sky. Mercury is the brightest, and most difficult to spot. The observer must have an unobstructed horizon. Mercury is two degrees above the horizon and appears a bit over half illuminated. Mercury sets at 7:36 PM.

Saturn and Mars are easier. Both are moderately high in the southwest and can be spotted through binoculars. Saturn appears creamy white, while Mars is famous for its red tint. Saturn is slightly brighter and lies sixteen degrees west of Mars. Saturn remains in Libra, while Mars migrated to Scorpius and is closing in on its rival, the star Antares. Binocular users can see the globular star cluster M-80 next to the Red Planet. Both set by9:30 PM.

Nightfall sees Neptune and Uranus enter the scene. Neptune rose in Aquarius before sunset. Uranus rises in Pisces during dusk. Finder charts for these distant worlds are available in astronomical media. Neptune setsat 4:42 AM; Uranus remains up all night.

Comet Jacques is still well positioned for observation. It has moved from Cygnus into the small constellation of Sagitta. The comet is best observedat 10 PM, when it lies due South and almost overhead. At 9th magnitude, it is barely visible to binoculars, but most telescopes should be able to show it. The comet lies about seven-and-a-half degrees south of Anser, the brightest star in Vulpecula and four-an-a-half degrees north of the star Zeta Aquilae, in Aquila – the Eagle.

Jupiter makes its appearance at 2:47 AM and remains in Cancer rest of the night. Just before Dawn, it is high enough for observation. At 3:54 AM on Tuesday, telescopic observers can see the Galilean Moon Io reappear from behind the giant planet. On Wednesday, at 5:30 AM, they can see the Great Red Spot, a giant storm on Jupiter.

Two weeks ago, the Skywatch Line drew attention the Harvest Moon and defined it as the Full Moon closest to the Autumnal Equinox. Monday at 10:29 PM, the Sun crosses the imaginary equator in the sky. This intersection of the Sun's path and the Celestial Equator is called the Autumnal Equinox and brings Fall to the Northern Hemisphere and Spring to those south of Earth's Equator. Daylight drops off dramatically. The Sun sets earlier and rises later. The Sun keeps heading lower in the sky until it hits bottom at the Winter Solstice, when the upward cycle begins.

This is Dudley Observatory’s Skywatch Line for Friday, September 19, through Sunday, September 21, written by Alan French.

The Moon was at last quarter last Tuesday and is now approaching new, which occurs very early this coming Wednesday. A slender waning crescent Moon will grace the pre-dawn skies this weekend. The Moon rises at 3:14 am Saturday morning, 4:11 Sunday morning, and 5:08 Monday.

Look for a nice pairing of the thirteen percent illuminated Moon toward the east around 6 am Saturday morning, when Jupiter will be about six degrees to the upper left of the Moon. By Sunday morning the Moon’s eastward motion among the stars will have moved it well below Jupiter.

With dark evening skies, two public star parties are scheduled this weekend. There is also a chance to get some safe views of the Sun through some specially equipped telescopes.

If the skies are clear, the Albany Area Amateur Astronomer will host a public star party in the Deerfield Pavilion area of Grafton Lakes State Park at 7:30 pm on Friday, September 19. At star parties a variety of telescopes are set up to show guests celestial sights, including star clusters, nebulae, galaxies, and double stars. If the skies are cloudy Friday night, it will be rescheduled for Saturday, September 20 – if the skies cooperate.

There is another public star party at the Octagon Barn in Knox at 7:00 pm on Friday, September 19. There is an indoor program, which will be held rain or shine, followed by a star party if the skies are clear. The barn is located at 588 Middle Road, Delanson, New York 12053.

Weather permitting the Albany Area Amateurs will have safe solar telescopes at the Five Rivers Fall Festival on Saturday, September 20, from Noon to 4 pm. These special telescopes will show sunspots in white light and prominences in the light of glowing hydrogen. In addition to solar viewing, the festival features many activities for families. For more details, visit their web site. Five Rivers Environmental Education Center is located in Delmar, NY at 56 Game Farm Road.

Never look at the Sun with a regular telescope! You’ll permanently damage your eye. You can learn about safe solar viewing here.

This is the Dudley Observatory Skywatch Line for Wednesday, September 17th and Thursday, September 18th written by Louis Suarato.

Wednesday, the 33% illuminated, waning crescent Moon sets at 3:14 p.m. EDT. One hour after the sun sets, at around 8:00 p.m., look over the southwest horizon to see the planet Mars just 0.5 degrees to the upper right of the star, Delta Scorpii. Mars will be flanked by Antares to the left and Saturn to its right. Wednesday is the 250th anniversary of the birth date of John Goodricke, who at age 18, discovered the variability of the star, Algol. Algol, in the constellation Perseus, is a three-star system with a magnitude of 2.1. Every 2 day, 20 hours and 49 minutes, Algol’s magnitude drops to 3.4 as a result of approximately 10 hour partial eclipses. Algol will next reach its minimum brightness on Thursday at 2:06 p.m. EDT. Look for Algol as the constellation Perseus rises in the northeast after 9 pm. Algol can be found to the lower right of Perseus’ brightest star, Mirphak. Above Perseus and below Cassiopeia is the Double Cluster. The Double Cluster (NGC 869 and NGC 884) is comprised of two close star clusters just a half degree apart and visible to the naked eye under dark skies. Binoculars convert the hazy patch of light to two fields of stars with contrasting colors with the backdrop of Milky Way stars.

Comet Jacques (C/2014 E2) has traveled beyond Cygnus and is heading toward Aquila. Look approximately 8 degrees past Albireo at the head of the Swan for Comet Jacques. The 30% illuminated, waning crescent Moon rises in Gemini at 1:22 a.m. Thursday. Jupiter rises in Cancer around 3 am. Early risers can view Comet Panstarrs (C/2012 K1) to the lower right of Jupiter and 27 degrees below the Moon in the constellation Hydra. Comet Panstarrs is anticipated to be 6th magnitude.

This Friday, beginning at 7:30 p.m., the Albany Area Amateur Astronomers will be hosting a Star Party, weather permitting, at the Deerfield Pavilion in Grafton Lakes State Park. In the event of clouds, the Star Party will be rescheduled for Saturday night.

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, September 15th and 16th written by Joe Slomka.

The Sun sets at 7:05 PM; night falls at 8:41. Dawn breaks at 5 AM and ends with sunrise at 6:36.

The darkening sky presents three bright planets. Mercury hovers very low in the West. An observer must have an unobstructed horizon, because the elusive planet is only three degrees above the horizon. The 0.1 magnitude planet appears about two-thirds illuminated. Mercury sets at 7:51.

Saturn, at 0.6 magnitude, is dimmer than Mercury, but is much higher in the Southwest. Its creamy color distinguishes it from the stars. Binoculars reveal its oval shape, while telescopes display the famous ring system. Under high powers, telescopes will also show one or more of its 62 moons. Mars, twelve-and-a-half degrees to Saturn’s left, is slightly dimmer, and appears small in most instruments. Mars has now crossed the border into Scorpius and approaches its rival, the star Antares. Mars and Saturn set by 9:45.

Nightfall adds Neptune to the planetary count. It still resides in Aquarius as a blue-green ball. Uranus rose, at 7:50, in Pisces. These two gas giants remain up the rest of the night. Observing charts are found in astronomy magazines, websites and apps.

Comet Jacques is still visible in our sky. At magnitude 12.6, it is probably no longer visible in binoculars, but still available in amateur telescopes. The comet lies due South at twilight’s end. It lies about two degrees south of the double star Albireo – the nose of Cygnus, and about one degree above the star Anser – alpha Vulpeculae. It sets at about 4:30 AM.

The twenty-day-old Moon rises at 11:38 Monday night near the horns of Taurus, the Bull. It rises at 12:29 AM Wednesday near Gemini’s feet. The Moon turns Last Quarter on Monday night and appears half illuminated; observers see it about one third illuminated on Wednesday.

Jupiter rises at about 3 AM in Cancer. Telescopes and binoculars show off the Galilean Moons and reveal the cloud bands. The Great Red Spot, a giant storm, is visible at 4:47 AM, Wednesday. Observers should also look six degrees above Jupiter to see the Beehive star cluster, also in Cancer.

With Comet Jacques so close to the bright star Albireo, let us consider this star. Albireo is the second brightest in the constellation of Cygnus; therefore, it is called Beta Cygni. It is the brightest star in the middle of the Summer Triangle. High powered binoculars or any telescope readily shows it to be a double star – universally considered the most beautiful. Most people describe it as yellow (gold) and blue (sapphire). It is about 430 light years away. The two stars are separated by 4400 times the average Earth-Sun distance. The “A” star is third magnitude and 760 times the Sun’s mass; the “B” star is fifth magnitude and only 120 times larger. But the “A” star has a secret; in the 1970’s, astronomers discovered that it is a triple. These stars are so close, that only their light spectra give them away.

This is Dudley Observatory’s Skywatch Line for Friday, September 12, through Sunday, September 14, written by Alan French.

The Moon was full at 9:38 pm last Monday and will reach last quarter next Tuesday, so a waning crescent Moon rises late in the evening. The Moon rises at 9:24 pm on Friday, 10:05 pm on Saturday, and 10:50 pm on Sunday.

If you look toward the north at 9:00 pm you’ll see the familiar pattern of the Big Dipper low toward the north northwest. Four stars outline the bowl of the dipper, and three more, stretching upward toward the west, mark its handle. This pattern of stars is an asterism, and it is formed by the most conspicuous stars of Ursa Major, the Great Bear. Under dark skies, away from major city lights, look for another pair of stars in front of the bowl, and then another single star to their right. The pair marks his shoulders, and the single star his nose.

Look for lines of stars going downward from the shoulders and a single line, quickly dividing into two, from the back of the bowl. These outline one of the bear’s front legs and his two rear legs. Each ends in pairs of stars marking toes, but these may be obscured by trees or other objects near the horizon.

The Iroquois of the St. Lawrence Valley and Micmac of Nova Scotia saw a different picture in the sky. The four stars of the dipper’s bowl marked the bear’s feet. The stars of the handle and stars arcing across the sky from the end of the handle through bright, reddish Arcturus were seven American Indians chasing the bear across the sky. Starting with the star next to the bowl, the handle represented Robin, Chickadee, and Moose Bird. Moving toward Arcturus we come to Pigeon, Blue Jay, and Owl, with Owl represented by Arcturus. Beyond Owl we find Saw-Whet.

If you look above Blue Jay you’ll see a semicircle of stars, Corona Borealis, the Northern Crown. With the addition of faint stars giving it a top, this became the Bear’s Den.

Looking closely at Chickadee, the middle star in the handle, you’ll see that it is actually two stars close together. The fainter star is the cooking pot for the bear.

From our latitude the Big Dipper is circumpolar, which means it never sets in its journey across the sky. But you’ll need a good view to the north to see it all when it is low in the north. Just after 3:00 am Alkaid, the star we’ve called Moose Bird at the end star in the handle, is just over two degrees above the horizon. If you travel farther south than New York City, Alkaid will briefly dip below the horizon.

This is the Dudley Observatory Skywatch Line for Wednesday, September 10th and Thursday, September 11th written by Louis Suarato.

The 95% illuminated, waning gibbous Moon rises in the constellation Pisces a few minutes after 8 p.m. Wednesday night. As the Moon is rising, Scorpius’ brightest star, Antares, and the planets, Mars and Saturn, form a line while setting in the southwest. High, overhead, Comet Jacques is traveling along the neck of Cynus the Swan and heading toward the star Albireo. The popular blue and gold double star, Albireo, and Comet Jacques, will be within 2 degrees on the night of September 14th. The neck of Cygnus the Swan lies along a dense part of the Milky Way and is worthwhile exploring with binoculars. Cygnus is also the home of the North America nebula and Veil Nebula. You’ll find the North America Nebula a few degrees from Deneb at the tail of the Swan. The Veil Nebula is just above the middle of Cygnus’ longer “wing”.

Wednesday night, at 10 p.m. EDT, the Moon passes 1.1 degree north of Uranus. Uranus, the seventh planet from the Sun at approximately 20 astronomical units, or 1.8 billion miles, shines at magnitude 5.8. Uranus completes one revolution around the Sun once every 84 Earth years. Uranus will appear to be blue-green in color, a result of the large amount of methane in its atmosphere. Uranus reaches opposition on October 7th.

Thursday’s pre-dawn sky features Jupiter in the constellation Cancer, and Venus, closer to the eastern horizon in the glow of the Sun. Venus continues to approach the Sun until it reaches superior conjunction on October 25th. We’ll see Venus as an evening “star” again in mid to late December.

On Friday, September 12th, the Albany Area Amateur Astronomers will be hosting a star party at the Colonial Acres Golf Course in Glenmont, NY. Join us as we point out constellations, and view celestial objects including the rings of Saturn, colorful double stars, and the immense Andromeda Galaxy through telescopes. The address for Colonial Acres Golf Course is 14 Saybrook Drive, Glenmont, NY.

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, September 8th and 9th written by Joe Slomka.

The Sun sets at 7:18 PM; night falls at 8:55. Dawn breaks at 4:50 AM and ends with sunrise at 6:28.

The Moon and two bright planets grace the early evening sky. The Moon rises at 6:55 PM and turns officially full at 9:38 Monday evening. A Full Moon means that it rises around sunset and sets around sunrise. More about this Full Moon in a minute. The Moon’s brilliance will wash out most of the night’s dim, distant sights.

Bright Saturn and Mars are moderately low in the southwestern sky. Last month, they appeared quite close; now, they are separating. They are about nine degrees apart. Last month, they were equally bright. Now, Saturn is slightly brighter at magnitude 0.6, even though it is much further away. Mars is slightly dimmer, due to its increasing distance from Earth. Saturn is still a great telescopic object, showing off its famous ring system; Mars is a small red spot in most amateur telescopes. Saturn appears in the western part of Libra, while Mars is racing eastward and preparing to leave Libra for Scorpius. Mars is approaching the bright star Antares. It is interesting to compare Antares and Mars. Antares is slightly dimmer than Mars now; but both share the same red hue. The word “Antares” is usually translated as the “Rival of Mars.” Antares is red because it is an old, bloated star; Mars is red because its soil is full of iron oxide – rust. Both planets set around 10 PM.

Seventh magnitude Neptune resides in Aquarius, while brighter Uranus is close to the Full Moon in Pisces. The Moon’s brilliance makes observation very difficult for most amateurs. Both remain up the rest of the night.

Jupiter rises in Cancer before Dawn. By Dawn, it is high enough to observe its four Galilean Moons. Venus rises during Civil Twilight about 23 degrees to Jupiter’s lower left. Venus, second in brightness only to the Moon, appears almost “full;” it continues is descent into the solar glare.

The Moon turned "Full" this evening. This is the third “Super Moon” of the year and also the third closest – only 222,692 miles from Earth. Astronomers call it a “perigean Moon,” which means “close to Earth.” It is the famous Harvest Moon, defined as the Full Moon nearest the Autumn Equinox. The Harvest Moon is special because the fall harvest could be conducted without daylight. Usually, the Moon rises about an hour later each night. However, due to the shallow Moon’s path in the sky, called the ecliptic, this time of the year has the Moon rising between twenty minutes and a half hour later. Pre-tractor farmers had the Moon to work by. This grace period lasts only until September 21st, when moonrise gradually lengthens to its normal interval.

This is Dudley Observatory’s Skywatch Line for Friday, September 5, through Sunday, September 7, written by Alan French.

The Moon reached first quarter early this past Tuesday so a bright waxing gibbous Moon will dominate the night sky this weekend. It will reach full at 9:38 pm on Monday.

Alas, we are slowly losing lovely ringed Saturn. At 8:00 pm, when the sky is fairly dark, Saturn is only twenty degrees above the horizon. Planet observers prefer viewing the planets when they are high in the sky and viewed through a thinner layer of our image distorting atmosphere. But the planet’s bright rings are still easily visible through even a modest telescope magnifying 30 times, and are even more impressive at higher magnifications through a 4-inch or larger aperture telescope. Saturn will still be around for a while, vanishing into the evening twilight at the end of October.

Saturn and its rings are now tipped about 22 degrees, so the planet’s moons can appear to travel well above and below the planet. The brightest and largest moon, and second largest in the solar system, is Titan. It is bright enough to spot in any telescope and appears as a star close to the planet. At 8:30 pm on Friday night, Titan will be to the upper right of Saturn. By Saturday its orbital motion will have moved it so it appears above the planet, and by Sunday it will be to the upper left.

Keep in mind that some telescopes invert the view, or reverse it. Look at a celestial object before the sky darkens to see the orientation of objects in your telescope. When you do this experiment use the same eyepiece orientation you expect to use on Saturn low in the south southwest.

Jupiter now rises just after 3:30 am and is almost 20 degrees above the horizon at 5:30 am, when morning twilight faintly illuminates the eastern sky. If you have a good view to the east, you’ll see bright Venus just above the horizon a little north of due east. Gracing the southeastern sky will be a preview of our winter skies, dominated by Orion, the Hunter, and the bright stars of the Winter Circle; Rigel, Aldebaran, Capella, Castor, Pollux, Procyon, and Sirius, the brightest of them all and the brightest star in our night sky.

If you enjoy astronomy and the night sky consider visiting the Astronomy Picture of the Day on a regular basis. The Earth Science Picture of the Day is also a fine site, and frequently has pictures of astronomical or atmospheric interest. Another good site for photos is Spaceweather. They feature interesting photos and have several dedicated photo galleries.

The Dudley Observatory Skywatch Line for Wednesday, September 3rd and Thursday, September 4th written by Louis Suarato.

Mars and Saturn are separated by 6 degrees as they appear over the southwestern horizon after sunset Wednesday evening in the constellation Libra. The 67% illuminated, waxing gibbous Moon, to the south of the planets, sets just after midnight. Luna highlights of the phase include the 58 mile-long crater, Copernicus, in Mare Insularium. Between the Moon and two planets is Scorpius’ brightest star, Antares, which shines at magnitude 1.05. On September 28th, the red planet Mars, and red star,Antares, will be within 3 degrees. There are four Messier objects in Scorpius, M4, M6, M7 and M80, all star clusters. M4 and M80 are globular clusters and M7 and M80 are open clusters. The open cluster M7, also known as the Ptolomy Cluster, is approximately 980 light years away and can be found between Scorpius and Sagittarius. M7 is about four degrees below the Teapot asterism’s spout, and 4 degrees northeast from the star Lamda Scorpii in the Scorpion’s tail. This very large open cluster, equal to two full moon diameters, can be seen easily through binoculars. Comprised of about 80 stars, the brightest stars in this open cluster range from magnitude 5.6 to 9.0. M7 is the southernmost Messier object.

Comet Jacques can be found Wednesday night 11 degrees to the north of Deneb, the brightest star in the constellation Cygnus, and the tail of the “Swan”. Comet Jacques is estimated to be at magnitude 7 and can be seen through small telescopes. Thursday night, Comet Jacques will be 5 degrees from Deneb.

Jupiter rises in the constellation Cancer 3:46 a.m. Thursday, followed by Venus in Leo at 5:15. Venus reaches perihelion, its closest distance to the Sun, on Friday at 5 am. Venus passes 0.8 degrees north of Leo’s brightest star, Regulus, on Friday. Look low in the east a half hour before sunrise.

The Albany Area Amateur Astronomers invite you to join them at Grafton Lakes State Park as we participate in International Observe the Moon Night on Saturday night beginning at 8 pm. There will be a short talk given about the formation of the Moon, followed by observing our nearest celestial neighbor. There will also be activities geared for small children. The link for this event can be found at http://observethemoonnight.org/

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, September First and Second written by Joe Slomka.

The Sun sets at 7:30 PM; night falls at 9:10. Dawn breaks at 4:41 AM and ends with sunrise at 6:21.

After the Labor Day sunset, the Moon and two planets occupy the southern sky. It turns First Quarter at 7:11 tomorrow morning. As Monday’s sky darkens, the brilliant Moon occupies the head of Scorpius; Tuesday finds it below Ophiuchus. It sets around Midnight on both nights.

Mars and Saturn appear to the Moon’s lower right; both are equally bright. Mars continues its race eastward; it remains at almost the same altitude all month. Saturn is left behind, even though it too crawls to the East. Mars, even in high-powered telescopes is a tiny ball; Saturn, on the other hand, shows off its glorious ring system even in small, low-powered, telescopes.

Nightfall sees Neptune, which rose at 7:18 PM, high enough for observation in Aquarius; it reached opposition last Friday, and is up all night. Fifth magnitude Uranus has just risen and is also an all-nighter in Pisces. Finder charts for both are found in astronomical websites, magazines and apps.

Jupiter begins a thirteen-month appearance. It rises before Dawn in Cancer, and is observable by Civil Dawn. Binoculars and low-powered telescopes reveal its four Galilean Moons. Brilliant Venus appears to Jupiter’s lower left. Tuesday finds it about 15 degrees lower; Wednesday has it 16 degrees lower. Jupiter continues to rise, while Venus dives into the solar glare this month.

Two comets pose challenges to observers. At twilight’s end, Comet Jacques shines at 11th magnitude about six-and-a-half degrees above the bright star Deneb in Cygnus. Early risers can try for Comet Oukaimeden in pre-dawn southeastern skies. The seventh magnitude comet should make it available to small telescopes. However, the viewer should work quickly; Dawn beaks at 4:41 AM. This comet is about ten-and-a- half degrees southwest of the bright star Procyon. Astronomical media will provide observing guides.

At midnight, the Great Square of Pegasus is relatively high in the East. If you follow the chain of stars springing from the upper left star, you see a hazy patch. The haze appears oval in binoculars. It takes a telescope to realize that it is a giant whirl of stars. Another hazy patch glows off the handle of the Big Dipper. For many years, these hazes were called “nebulae” – clouds. Astronomers of the Eighteenth and Nineteenth Centuries could not make out details and thought that they were part of our own galaxy. It took the new, powerful telescopes of the Twentieth Century for observers to realize that they were complete “island universes.” Each was composed of hundreds of millions of stars at great distances from our own island universe – The Milky Way.

This is Dudley Observatory’s Skywatch Line for Friday, August 29, through Sunday, August 31, written by Alan French.

The Moon was new this past Monday and is now moving toward first quarter, so a waxing crescent Moon will grace the early evening skies. It will reach first quarter early this coming Tuesday. The Moon sets at 9:25 pm on Friday, at 9:58 on Saturday, and at 10:36 on Sunday.

On Friday evening look for the crescent Moon toward the west southwest as darkness falls. Look for earthshine, the faint glow of the portion of the Moon not in direct sunlight. Earthshine is the light from a waning gibbous Earth in the Moon’s sky.

Also look for the bright star Spica, just below the Moon. The sky should be dark enough to spot Spica by about 8:15 pm, when the Moon will be ten degrees above the horizon and Spica one-and-a-half degrees below the lunar orb.

On Sunday night a fatter crescent Moon will form a nice trio with Saturn and Mars. Look for the grouping toward the southwest around 8:00 pm, with Saturn to the right of the Moon and slightly lower, just two degrees away, and Mars to the lower left and just under three degrees away. With the proper choice of foreground and lens focal length the trio should make a lovely photograph.

Weather permitting; the Albany Area Amateur Astronomers will take advantage of the early moonset to hold public star parties at Landis Arboretum in Esperance. The star parties will be held beginning at 9:00 pm on Friday, August 29, and Saturday, August 30.

At a star party members of the astronomy club set up telescopes to provide guests with views of a variety of celestial sights, including star clusters, nebulae, galaxies, and double stars. For those interested there will be a brief introductory program starting about 9:15 pm in front of the meeting house. It will include hints for getting the best telescopic views and a short tour of the prominent constellations.

These star parties will be held in the Meeting House field at Landis Arboretum. You can find directions to Landis here. Once you see the farm house on your right and a parking area on you left, continue up Lape Road about 100 feet. Turn into the Meeting House driveway on your right.

Star parties are open to all and there is no admission fee, although we do encourage guests to make a donation to our fine hosts, Landis Arboretum. A donation box is next to the south door on the Meeting House.

Star parties normally last at least an hour, and usually go much longer if the skies cooperate. Guests are welcome to stay as long or briefly as the wish.

This is the Dudley Observatory Skywatch line for Wednesday, August 27th and Thursday, August 28th written by Louis Suarato

The 5% illuminated, waxing crescent Moon sets at 8:24 p.m. Thursday evening, about 40 minutes after sunset. If you have a clear western horizon, you may be able to see Mercury setting 7 degrees to the north of the Moon. Above the southwestern horizon, Mars and Saturn are separated by 3.6 degrees in the constellation Libra. Scientists, using data collected by the Cassini spacecraft, have recently concluded that Saturn’s rings are much older than previously thought. The new data suggests Saturn’s rings are 4.4 billion years old, dating back to when the planet was formed. Cassini is expected to continue to gather data until 2017, when it will loop between Saturn and its rings before diving into the planet’s atmosphere. 

Comets are in the news as the European Space Agency’s (ESA) and NASA spacecraft provide some exciting views and prepare images of a Mars flyby. After traveling for 10 years and 4 billion miles, the ESA’s Rosetta spacecraft arrived at 10 billion ton Comet 67P/Churyumov-Gerasimenko on August 6th, becoming the first spacecraft to rendezvous with a comet. Rosetta is now providing images for possible landing sites for its contact robot, Philae, which is scheduled to touch down on the comet in November. From November 2014 to December 2015, the Rosetta orbiter will collect data as the comet approaches the Sun and then, travels away from it. Another comet in the news is Siding Spring. Comet Siding Spring will pass Mars on October 19, 2014 at approximately 82,000 miles, about a third of the distance of the Moon to Earth. NASA will attempt to image the comet with its Rovers and Mars orbiters as it passes the red planet. India’s MAVEN spacecraft will be arriving shortly before Siding Spring, and will also attempt to provide images. 

The brightest, observable comets in our skies include Comet Panstarrs (C/2012 K1). At magnitude 6.2, Panstarrs is 8 degrees east of Venus, but may be lost in the early morning glow of the Sun. Comet C/2014 E2 (Jacques) is at magnitude 10.85 and can be seen between the constellations Cassiopeia and Cepheus. A chart of this comet’s daily positions can be found on this Sky & Telescope web page:http://www.skyandtelescope.com/astronomy-news/observing-news/happy-times-comet-watchers-08202014/ 

 

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, August 25th and 26th written by Joe Slomka

The Sun sets at 7:41 PM; night falls at 9:24. Dawn breaks at 4:30 AM and ends with sunrise at 6:13.

The Moon turned “New” at 10:13 Monday morning; this ensures a dark sky for observers for the next few days. Tuesday, shortly after sunset, observers with an unobstructed horizon can try to spot a very young Moon. It appears about two percent illuminated, very low in the West and sets at 7:57 PM.

Also during twilight, Mars and Saturn glow low in the southwest. They are equally bright and are separated by about three degrees. Saturn appears creamy white and higher; Mars is below Saturn and sports a distinctive red hue.

Neptune rises shortly after sunset and is at opposition on Friday night. It appears as a blue-green spot in Aquarius. Uranus rises at 9:14 PM in Pisces. Both remain up the rest of the night. Observing charts for both planets are available in astronomy magazines, websites and apps.

The constellation Perseus is well up after Midnight. At 2:11 AM on Tuesday, the star Algol (also known as Beta Persei) dims. Algol, the “Demon Star,” varies its light every 2 days, 20 hours and 49 minutes. It fades from second magnitude to third – easily seen by the naked eye. The entire cycle takes about nine hours. Two hundred twenty-six years ago, John Goodricke theorized that a dimmer star was partially eclipsing a brighter star. In 1889, the new technique of spectroscopy verified this theory. The main star is one hundred times the Sun’s luminosity. The eclipsing star is actually slightly brighter than our Sun. There is a third star that orbits the system once every 1.8 years, but plays little part in the occultation. The system is about 96 light years away and the most easily studied “eclipsing binary.” Astronomy magazines and websites provide timetables of its eclipses.

Jupiter rises before Astronomical Dawn and glows below M-44 (The Beehive star cluster). Tuesday morning finds it one and three=quarters degrees below; Jupiter comes closer on Wednesday. During Civil Dawn, Venus appears about eight degrees to Jupiter’s lower left. Jupiter continues to rise, while Venus dips ever closer to the horizon.Tuesday morning, Venus is eight degrees below the giant planet; Wednesday, Venus sinks a degree lower.

This is Dudley Observatory’s Skywatch Line for Friday, August 22, through Sunday, August 24, written by Alan French.

First, a correction to last weekend’s Skywatch Line. I wrote that Jupiter and Venus would be closest on Sunday morning and that it was the closest planetary pairing of 2014. They were actually closest on Monday morning. My apologies for this error.

We start the weekend with a lovely pass of the International Space Station, traveling high over the Capital District region on Friday night. The sky will still be bright with evening twilight, but the bright ISS should be easy to spot as it glides across the sky.

It will first appear at 8:21 pm Friday rising up from the west northwestern horizon. It will be highest just after 8:24 when it will be 78 degrees above the southwestern horizon – essentially overhead. (If you miss it coming up from the horizon, look for it overhead, moving toward the south southeast, at 8:24 pm.) It will vanish low in the south southeast at 8:27:31 pm.

It’s nice to have the correct time when you are looking for satellites. Today most digital devices maintain very accurate times. You can also get the official time here.

Friday night also features a Dudley Observatory talk and star party at the Octagon Barn in Knox beginning at 8:00 pm. The barn is located at 588 Middle Road, Delanson, NY.

Venus is now rapidly moving lower in the predawn sky, increasing its separation from fainter Jupiter. On Saturday morning they will be just over five degrees apart, and joined by a lovely, slender crescent old Moon. Look for the trio in the east northeast around 5:10 am. With a proper foreground and choice of focal length and exposure this trio would make a nice photograph.

With a very old Moon rising just before dawn this weekend’s night skies will be nice and dark, perfect for star gazing. From a dark site well away from city lights the hazy band of the Milky Way now crosses high in the sky at 9:30 pm, rising up from the south southwestern horizon, arching a bit east of directly overhead, with bright Vega to its west, and then heading downward to the north northeast.

Look toward the south, not far above the horizon, for a teapot shaped pattern of stars, with the spout to the right. These stars outline Sagittarius, the Archer. The Milky Way looks like steam rising from the teapot’s spout. Exploring the length of the Milky Way with binoculars will reveal many fine sights.

This is the Dudley Observatory Skywatch Line for Wednesday, August 20th and Thursday, August 21st written by Louis Suarato.

The 19% illuminated, waning crescent Moon sets at 4:34 p.m. Wednesday, leaving the skies darker for observing. After sunset, look over the southwestern horizon to see Saturn about 4 degrees to the upper left of Mars in the constellation Libra. Libra’s brightest star, Zubeneschamali, or Beta Librae, shines above Saturn at magnitude 2.60. Zubeneschamali in Arabic means “The Northern Claw”, which was derived when the stars of Libra were thought as the claws of Scorpius. The star Zubenelgenubi, or Alpha Librae, shines above Mars at magnitude 2.75. Zubenelgenubi means “Southern Claw” in Arabic. It was the Romans who defined Libra as a separate constellation. During the first century, when the Sun was in Libra during the fall equinox, and day and night were in balance, the Romans associated Libra with the goddess Astraeia, or Virgo, holding the scales of justice. Libra is the only constellation of the zodiac that doesn’t represent a living thing.

A thinner crescent Moon rises at 2:34 a.m. Thursday in Gemini. Jupiter and Venus follow about 3 hours later in the constellation Cancer. The two planets are now separated by approximately 4 degrees with Jupiter above Venus. Friday morning, the crescent Moon will shine above and right of the pair.

There will be several astronomy events taking place in our area this week. The Albany Area Amateur Astronomers will be hosting a star party, weather permitting, at the Landis Arboretum in Esperance, NY on Wednesday night, after their monthly club meeting. Amateur astronomers will be setting up telescopes for public viewing at the top of the hill near the meeting house. There is also a star party scheduled at Grafton Lakes State Park on Friday night at the Deerfield Pavillion. In the event of cloudy weather, this star party will be rescheduled for Saturday night. In addition, the Dudley Observatory will be hosting a lecture followed by a star party at the Octagonal Barn beginning at 8 pm on Friday, August 22nd . The barn is located at 588 Middle Road, Delanson, New York 12053.

This is the Skywatch Line for Monday and Tuesday, August 18th and 19th written by Joe Slomka.

The Sun sets at 7:52 PM; twilight ends at 9:39. Dawn breaks at 4:19 AM and ends with sunrise at 6:06.

After sunset, two bright planets appear in southwestern skies. Both Saturn and Mars are identically bright at first magnitude and share Libra. Mars has been chasing Saturn for the last few months; next week it is in conjunction with the Ringed Planet. Mars is bright red, about five degrees to Saturn’s right. Even under high powers, Mars is a disappointing tiny red ball. Saturn, even in small telescopes, shows off its glorious ring system. Mars sets at 10:46 PM; Saturn follows at 11:14.

Neptune rises in Aquarius at 8:14 PM, and is best observed at 1:39 AM. Similar appearing Uranus rises at 9:42 PM and is highest at 4:05 AM. Observing charts for both planets can be found in astronomy magazines, websites and apps.

Tuesday’s Moon rises at almost 1 AM in the Hyades star cluster. It appears about 31 percent illuminated. Wednesday’s twenty-five day-old Moon rises at 1:42 AM and occupies Orion’s Club. The Moon’s brilliance will obscure dimmer deep sky objects for the rest of the night.

Monday’s pre-dawn sky displayed a spectacular pair of brilliant Venus and slightly dimmer Jupiter very close to each other. Tuesday’s pre-dawn sky sees the pairing start to separate. Tuesday at about 5:36 AM, they are a bit over one degree apart. Wednesday finds the two planets over two degrees from each other. Jupiter also lies 1.2 degrees from the Beehive Star cluster, which may be difficult to spot amid the brightening sky. This appulse is the closest in fourteen years.

Midnight sees the rise of two star clusters: the Pleiades and the Hyades. The Pleiades rise first and resemble a mini dipper, while the Hyades, rising an hour later, form the face of Taurus, the Bull. In Greek myth, the Hyades and Pleiades are related, both daughters of Atlas and Aethra- both seven in number. The name Hyades derives either from the story of the sisters mourning the death of their brother Hyas, or from the Greek verb "to rain," since the Hyades' rise signals the rainy season. They were placed in the sky as a reward for babysitting the infant god Bacchus. The Hyades is the second closest cluster to Earth, second to the Ursa Major cluster. It is about 400 million years old. This cluster is about 150 light-years away and part of the "Taurus Moving Cluster" of stars that are heading towards the star Betelgeuse. The bright star Aldebaran is not a member of this group, and actually midway between Earth and the Hyades.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, August 15, through Sunday, August 17, written by Alan French.

The Moon reaches last quarter early Sunday, so a gibbous waning Moon rises late on Friday and Saturday evenings. Moonrise on Friday is at 10:49 pm and on Saturday it is at 11:28 pm. By Sunday the Moon will rise just after midnight, appearing slightly less than half illuminated. If you’re up before dawn, the days right around last quarter are ideal for exploring the Moon through binoculars or a telescope.

Attentive early morning sky watchers may have noticed Venus rapidly approaching Jupiter as it moves lower in the early twilight skies. The pair was about six degrees apart this past Tuesday morning, and the distance has been closing by approximately one degree a day.

If you look toward the east northeast at 5 am Saturday morning you’ll spot brilliant Venus just two degrees above bright Jupiter. By Sunday morning they will be separated by less than a degree. This is the closest planetary conjunction or pairing for 2014.

We see satellites because they are still up in the sunshine while we are down in the Earth’s shadow. As they pass overhead their path may take them into the shadow so they will fade from view. A pass of the International Space Station on Saturday night will do this vanishing act while still high in the sky.

The ISS will first appear at 9:57 pm in the northwest. It will reach its highest point seconds after 10:00 pm when 45 degrees above the north northeastern horizon and will then quickly move into the Earth’s shadow and fade from view. See how long you can follow it after it begins to fade.

Its path across the sky will take it through the front of the Big Dipper’s bowl, very close to Polaris, the North Star, and it will fade from view as it is passing above the distinctive “W” of Cassiopeia, the Queen.

As you watch the station think of the six astronauts now living there, perhaps enjoying a view of our lovely Earth. Three have been there 143 days as of Friday, and the other three only 79 days. You can keep track of the crew at this website.

The Dudley Observatory Skywatch Line for Wednesday, August 13th and Thursday, August 14th written by Louis Suarato.

Two planet pairings continue to be the features of our evening and early morning skies. In the evening, look over the southwestern horizon to see golden Saturn to the upper left of reddish Mars. Both planets are flanked by the stars Antares, to the south, and Spica, to the west. Antares, also known as Alpha Scorpii, is the brightest star in the constellation Scorpius and the seventeenth brightest in the nighttime sky. Antares is a red supergiant star, 550 light years from Earth, with a diameter 883 times that of our Sun. Antares has a companion star, Antares B, which may be seen in telescopes with apertures larger than six inches. Spica, or Alpha Virginis, is the brightest star in the constellation Virgo, and the fifteenth brightest star in the nighttime sky. Spica is a blue giant star located 262 light years from Earth, and about twice the size of our Sun. Spica is also a binary star with the two stars orbiting each other every four days. Wednesday night, Saturn and Mars will be separated by 7.8 degrees. The gap between these planets will shrink to 3.4 degrees on August 25th. The pre-dawn sky planet pairing is Venus above Jupiter. The two planets will be separated by about 4 degrees Thursday morning. Follow the pair as their separation narrows by 1 degree per day until Venus and Jupiter are only 0.3 of a degree apart on the morning of August 18th.

The 85% illuminated, waning gibbous Moon rises in the constellation Pisces around 9:30 p.m. Wednesday night. Look with binoculars or a small telescope for Uranus about 7 degrees to the lower left of the Moon and about 2 degrees to the right of the 4.25 magnitude yellow-orange star, Epsilon Piscium. You can find 7.65 magnitude Neptune, also with the aid of binoculars or a small telescope, in the constellation Aquarius. Star hop to Neptune by finding Aquarius’ brightest star, 2.95 magnitude, Sadalmelik, go down about 8 degrees to 4.15 magnitude Ancha, and on to Neptune, 4 degrees to the lower left of Ancha. August 13th is the birth date of the astronomer Heinrich Ludwig d’ Arrest. It was d’ Arrest’s suggestion of comparing the region of the sky calculated by Urbain Le Verrier to a current sky chart that led to the discovery of Neptune.

This is the Skywatch Line for Monday and Tuesday, August 11th and 12th written by Joe Slomka.

The Sun sets at 8:05 PM; night falls at 9:53. Dawn breaks at 4:08 AM and ends with sunrise at 5:58.

The Moon became the “Full Sturgeon Moon” yesterday. As a result, a nearly full Moon rises shortly before Sunset and remains up the rest of the night. The Moon’s brilliance washes out dim objects like faint planets and meteors.

The annual Perseid Meteor Shower peaks Tuesday night – Wednesday pre-dawn. As mentioned above, the Full Moon complicates observation of all but the brightest meteors. Observers should dress warmly, find a reclining chair, bundle up with a blanket and face where the sky is darkest. The hours after Midnight are usually best.

Saturn and Mars are the few objects that defy the Moon. Both are equally bright and relatively low in the West. Mars is in the southwest; its red hue indicates its position. In binoculars or telescope, the Red Planet is a tiny ball. Saturn, on the other hand, is cream colored and a joy even in small telescopes. It lies about eight degrees east of Mars. Both set before Midnight.

Venus rises ninety minutes before Sunrise. Its brilliance is second only to the Moon. By Civil Dawn, it is moderately high in the East. In a telescope or high-powered binoculars, it appears nearly “full.” Jupiter rises a half-hour after Venus and appears to Venus’ lower left. They stage a very close conjunction on the 18th.

Since the Moon commands center stage, let us review the latest lunar science. During the last century, three theories about its formation were popular: the Earth and Moon formed together, it was captured by Earth’s gravity, or it split off of a rapidly spinning Earth.

Computer simulations and Moon rocks, retrieved by astronauts, inspired a new model: The Big Splat. According to this concept, a Mars-sized object sideswiped the new Earth, ejecting debris that temporarily formed a ring and later coalesced into the Moon. This hypothesis explains a number of things: isotopes of Earth and Moon rocks are very close matches; and, Moon rocks have little iron and no water. When did this cosmic crash occur? Recent analyses of xenon gases trapped in rocks indicate that it happened 4.53 billion years ago, when Earth was still molten. While this theory is widely accepted, it isn’t perfect, and requires further research.

The other question dates back to the early days of the Space Race. Since the Moon is tidally locked by Earth’s gravity, we can only see one side. In 1959, the Soviet space probe Luna 3 took photos of the Moon’s backside. It looked nothing like the front. Penn State researchers think they have the answer. After the Big Splat, the Moon was much closer to Earth and quickly became tidally locked. Both bodies were still hot from the collision. The lunar nearside was baked by Earth, while the far side cooled. The nearside was too hot for minerals to condense. When asteroids pummeled the Moon, the thin crust on the nearside fractured and oozed magma, which solidified into the maria we see. The backside was thicker and did not fracture enough for lava to seep onto the surface.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, August 8, through Sunday, August 10, written by Alan French.

The Moon reached first quarter late this past Sunday and will reach full at 2:09 pm on this Sunday. A bright, waxing gibbous Moon will dominate the sky on Friday and Saturday, and on Sunday the full Moon will rise at 7:48 pm just south of due east.

This will be the largest full Moon of 2014, with the Moon exactly full just 9 minutes after it reaches perigee, its closest point to Earth. When a new or full Moon occurs so close to perigee it has become known as a supermoon.

A full supermoon is 14 percent larger and 30 percent brighter than it would be at apogee, when farthest from Earth. Photographic comparisons can nicely show the difference in size, but it is not obvious to the eye. You can do the comparison yourself by taking a picture of Sunday night’s full Moon with a long focal length lens and then take a picture of the next full Moon near apogee, which occurs on March 5, 2015. Be sure to use the same focal length for both pictures. Mark your calendar!

On August 10, 1932, an eleven pond meteorite broke into pieces, which landed near the town of Archie, Missouri. Seven stones were recovered from the Archie meteorite.

A meteorite hit a parked car in Peekskill, NY, on Friday, October 9, 1992. As it streaked through the Earth’s atmosphere its passage was recorded in sixteen videos, many by people attending high school football games. Only the recent fireball over Chelyabinsk was better documented.

On April 12, 1968, a meteorite weighing about two-thirds of a pound struck the roof of a house in Glenville.

Wethersfield, Connecticut, has an usual claim to fame. On April 8, 1971, a 12 ounce meteor went through the roof of a house and lodged in the living room ceiling. Then, eleven and a half years later, a second meteor hit another house, less than two miles from the first.

The second meteor struck the roof of a house in at 9:17 pm on November 8, 1982, going through the roof and landing in the living room. The owners and fire department were very puzzled by the hole in the roof and ceiling until someone spotted the grapefruit sized meteorite underneath the dining room table.

This is the Dudley Observatory Skywatch Line for Wednesday, August 6th and Thursday, August 7th written by Louis Suarato.

One of the first stars to appear in our skies every evening is Arcturus, the brightest star in the constellation Bootes, and at magnitude -0.04, the brightest star in the northern celestial hemisphere, and the fourth brightest overall. Arcturus’ brightness is a factor of its relatively close proximity of 36.7 light-years from Earth, and its size of 23 times the diameter of our Sun. Arcturus moves at the speed of 122 kilometers per second relative to our solar system, and in about 4,000 years will be a few hundredths of a light-year closer to Earth than it is today. Look for Arcturus about 50 degrees above the western horizon after sunset. Binocular targets near Arcturus include the globular cluster, M3, 17 degrees to the west, and open cluster Mellotte 111, in the constellation, Coma Berenices, below and west of Arcturus. To the south, and below Arcturus, are Mars and Saturn descending toward the west-southwest horizon. Both planets will close within 3.5 degrees from August 23rd through August 26th. Another planet pairing occurs at dawn as Venus and Jupiter appear before sunrise. The two planets will be only 0.3 degrees apart on the morning of August 18th.

The 88% illuminated, waxing crescent Moon rises at 5:22 p.m. EDT Thursday. On Sunday, August 10th, the Moon will reach perigee at 221,765 miles from Earth at 1:43 p.m. EDT. Twenty-six minutes later the Moon will reach its Full phase and appear at its largest and brightest for the year. This conjunction of events will have a significant effect on tides. For an extreme example, next week, Hopewell Cape, in New Brunswick, Canada, will have a tidal swing of over 48 feet. Closer to home, Staten Island, NY will have a 7 foot tidal swing, compared to the normal 4 feet difference in tides. The Moon will set around 3:23 a.m. Friday.

This is the Skywatch Line for Monday and Tuesday, August Fourth and Fifth written by Joe Slomka.

The Sun sets at 8:12 PM; night falls at 10:07. Dawn breaks at 3:56 AM and ends with sunrise at 5:57.

After sunset, the eight-day-old Moon blazes in the southern sky. Monday, the darkening sky reveals the Moon to head up a southwestern line with Saturn, Mars and the bright star Spica. Tuesday sees the line extended, with a fatter Moon further eastward. The Moon sets after midnight on both nights.

Mars chases Saturn this month. They are separated by about 12 degrees. Both planets crawl eastward; however, Mars is faster due to its inside track. Later this month, they have a dramatic meeting. Both are almost the same brightness; but display different colors. Mars is obviously red, while Saturn is a creamy white. Mars is a tiny dot, even in a telescope, while Saturn amazes first time viewers with its ring system. Mars sets before midnight, Saturn after midnight.

Minor planet Ceres and asteroid Vesta become visible at nightfall. They co-inhabit Virgo with Mars. Both lie within two degrees from each other, and lie about eight degrees above the Red Planet. Astronomy websites, magazines and apps provide observing charts. Both set before Midnight.

Neptune rises after 9 PM in Aquarius, and remains up the rest of the night. It reaches opposition later this month and appears to head westward for the next few months. Uranus rises at 10:34 PM in Pisces and also remains up all night. Astronomical media provides finder charts for both planets.

Venus rises about 4 AM, and, by civil dawn, is high enough for observation. It appears almost full in our binoculars and telescopes. Jupiter rises about 5 AM. It is quite low and may be difficult to spot. Venus appears lower daily, while Jupiter hovers close to the horizon.

Most people think of astronomers as professional scientists. However, the first were priest-astrologers, who predicted seasons, planting times and told fortunes; the Magi are an excellent example. After the Renaissance, astronomers were usually rich people who built their own instruments and observatories; some were hired as royal astronomers. It was in the Nineteenth Century that astronomy became a professional study. Professionals study rather narrow fields: star evolution, black holes, galaxy formation, cosmic rays, etc. However, amateurs still contribute to the body of knowledge. Amateurs still scan the skies, looking for something new. They discover comets, supernovae, and brightening stars. These finds are reported for follow-up by specialists. Last weekend saw the annual Stellafane convention. Amateurs gathered from throughout the world to discuss telescope making techniques and the latest discoveries. If you have the chance, attend an amateur astronomy convention. You will find a welcoming atmosphere, and a whole new universe.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, August 1, through Sunday, August 3, written by Alan French.

The Moon was new last Saturday and will reach first quarter late this coming Sunday, so a crescent Moon will grace the early evening sky this weekend. Look for it low toward the west southwest Friday night after sunset, between Mars and Spica in the southwest on Saturday, and between Mars and Saturn on Sunday. By Sunday the Moon will not set until just before midnight.

Weather permitting, the Albany Area Amateur Astronomers will host a solar star party at Landis Arboretum, from noon to 2:00 pm on Saturday, August 2. Members of the Albany Area Amateur Astronomers will provide specially filtered telescopes to provide safe views of the Sun. The solar star party is canceled if the skies are mostly cloudy. Call 374-8460 if uncertain. (Never look at the Sun with a regular telescope! You’ll permanently damage your eye. You can learn about safe solar viewing here.)

The solar star party is free and everyone is welcome. We do, however, encourage guests to support our fine hosts, the Landis Arboretum, either through a modest donation or a membership.

Your can find directions to Landis Arboretum here. For an address, use 176 Lape Road, Esperance, NY. Once you reach Landis continue up Lape Road past the main farmhouse and parking area. Turn right at the “Star Party” sign, which will mark the driveway into the Meeting House field.

We have two chances to see the International Space Station (ISS) glide across Sunday’s evening skies. The ISS looks like a bright star gliding across the sky. The times are for Schenectady but should be close enough for anyone in the Capital District area.

The ISS will fist appear just after 9:15 pm Sunday rising up from the south southwestern horizon. It will be highest just after 9:18 when 35 degrees above the southeastern horizon, and will vanish in the east northeast just after 9:21. Its path will bring it up through Scorpius, passing very close to bright reddish Antares, and just below bright Altair in Aquila, the Eagle.

The second appearance Sunday will begin just before 10:52 pm when the space station will come up from the western horizon. It will be highest just before 10:55 when 36 degrees above north northwestern horizon. The ISS will move into the Earth’s shadow and vanish from view at 10:57 when 17 degrees above the northeastern horizon. Its path will take it well below bright Arcturus, through the handle of the Big Dipper, and it will fade from view after passing below the “W” of Cassiopeia.

The Dudley Observatory Skywatch Line for Wednesday, July 30th and Thursday, July 31st written by Louis Suarato

Wednesday evening, after sunset, the 14% illuminated, waxing crescent Moon shines about 15 degrees over the west-southwestern horizon. Follow the ecliptic plane to the Moon’s upper left to find Spica, Mars and Saturn. The ecliptic, or ecliptic plane, is the plane of the Earth’s orbit around the Sun. The orbits of other planets are, more or less, in the same plane as the Earth. The word “ecliptic” was derived from its relation to eclipses. The Moon’s orbit crosses the ecliptic at an angle of about 5 degrees and is located north of the ecliptic half the time and the other half south of the ecliptic. The Moon crosses the ecliptic twice during its 29.53 day complete phase, or synodic, cycle. If the Moon crosses the ecliptic moving northward, it is at the ascending node of its orbit. If the Moon crosses the ecliptic moving southward, it is at the descending node. While crossing this plane, if the Moon’s shadow hits the Earth, the Sun is eclipsed. If the shadow of the Earth covers the Moon, there is a lunar eclipse.

As the crescent Moon is setting, Vega, in the constellation Lyra, is approximately 70 degrees above the eastern horizon. Vega, at magnitude 0.0, is the second brightest star in the northern celestial hemisphere after Arcturus, and is the brightest of the Summer Triangle asterism stars, and therefore, very easy to spot. A binocular view will reveal a double star about 4 degrees to the east of Vega. That star is Epsilon Lyrae. A telescopic view of Epsilon Lyrae will show it to be a double double star or four stars which are gravitational bound. One pair of stars circles the other pair of stars. Epsilon 1 consists of stars with magnitudes of 4.7 and 6.2 which orbit their center of gravity once every 1,200 years. Epsilon 2 consists of stars with magnitudes 5.1 and 5.5 which orbit their center of gravity once every 585 years. The two pairs circle each other once every hundreds of thousands of years.

Thursday, Venus rises in Gemini, to the east of Castor and Pollux, in the pre-dawn sky at around 3:53 a.m. EDT. Mercury and Jupiter are still hidden by the glow of sunrise. The Dudley Observatory invites you to join them for a “Sun Party” this Sunday, August 2nd, beginning at noon. Solar-safe telescopes will be available for viewing various features on the Sun. The Sun Party will be held at the Museum of Science and Innovation (miSci) in Schenectady.

This is Dudley Observatory’s Skywatch Line for Friday, July 25, through Sunday, July 27, written by Alan French.

Reaching new late Saturday, the Moon will be absent from the weekend skies, leaving them nice and dark for star gazing. There are two star parties in the area this weekend – events where you can see celestial sights through a variety of telescopes.

Dudley Observatory will host a star party at the Octagon Barn in Knox at 8:00 pm on Friday, July 25. (For directions, use 588 Middle Road, Delanson, NY 12053.) The Octagon Barn is just west of the intersection of Middle and Beebe roads. The event will be held even if the skies are cloudy, with an indoor program and refreshments. Call (518) 618-5376 for more information.

Weather permitting, the Albany Area Amateur Astronomers, in association with New York State Parks, will hold a public star party in Grafton Lakes State Park beginning at 9:00 pm on Friday, July 25. If you arrive after dark, please use the winter entrance. For further information call Ray (658-3138) or Bernard (658-9144). If the skies are cloudy on Friday, the star party will be held on Saturday night, if the skies are clear. Call if in doubt.

This weekend’s dark skies will be a good time to look for the Milky Way, a hazy band of light from the distant stars along the plane of our galaxy. To see it you’ll need to be away from city lights. (Perhaps you can look for it at one of the star parties.) At 10 pm the band is most obvious rising up from the horizon, just a bit west of due south. It arcs high overhead, passing just east of Vega, the brightest star near the zenith.

The Milky Way is rich as it passes through Cygnus, the Swan, overhead and known to some as the Northern Cross. The Milky Way becomes more subtle as it approaches the familiar “W” marking Cassiopeia, the Queen. Exploring the Milky Way by eye or with binoculars from the comfort of a reclining lawn chair is an enjoyable way to spend a summer evening.

The next event at Landis Arboretum is a solar star party, starting at noon on Saturday, August 2. Members of the Albany Area Amateur Astronomers will provide specially filtered telescopes to provide safe views of the Sun. Look for more details on next weekend’s Skywatch Line. (Never look at the Sun with a regular telescope! You’ll permanently damage your eye. You can learn about safe solar viewing here.)

The Dudley Observatory Skywatch Line for Wednesday, July 23rd and Thursday, July 24th written by Louis Suarato.

Wednesday evening, about two hours after sunset, look over the west-southwestern horizon to view Virgo’s brightest star, Spica, 5 degrees to the right of Mars. Above the southwestern horizon is Saturn, 18 degrees to the left of Mars. Mars will pass 3.4 degrees to the south of Saturn on August 25, 2014. Scorpius’ brightest star, Antares, will be about 20 degrees over the southern horizon. The moonless night will allow for a good view of the globular cluster M4, located just 1 degree to the right of Antares. At a distance of 7,200 light years, M4 is one of the nearest globular clusters and one of the largest, and can be seen easily through binoculars. At a magnitude of 5.90, M4 is equal in brightness to the Great Globular Cluster in Hercules, M13. A 4-inch refractor will show resolution to this loose cluster of stars.

Thursday, at 3:01 a.m., there will be a very bright International Space Station pass over our region. The ISS will emerge from darkness overhead near Polaris and travel toward the northeast, under the star Capella, in the constellation Auriga. Stay up to watch the 6% illuminated, waning crescent Moon rise alongside Venus around 4 a.m. EDT. Venus and the Moon will be separated by 6 degrees. Look with binoculars about 4 degrees to the upper right of Venus for the open star cluster M35. A challenge will be to spot Mercury approximately 6 degrees below Venus.

The Dudley Observatory will be hosting an Octagonal Barn Star Party on Friday, July 25th at 8 pm. The barn is located at 588 Middle Road, Delanson, New York. There will be a lecture preceding the star party. The lecture will be held regardless of the weather and sky conditions. For those closer to Grafton Lakes State Park, the Albany Area Amateurs will be hosting their monthly Star Watch at the Deerfield Pavilion. The Star Watch will be rescheduled to Saturday in the event of clouds on Friday.

This is the Skywatch Line for Monday and Tuesday, July 21st and 22nd written by Joe Slomka.

The Sun sets at 8:27 PM; night falls at 10:31. Dawn breaks at 3:33 AM and ends with sunrise at 5:37.

As the Sun sets, only two planets are visible. Mars appears in the southwestern sky. Mars continues to shrink in size and brilliance. It lies about four degrees East of Spica, in Virgo. Mars sets before Midnight.

Saturn continues to inhabit Libra. Monday night, Saturn halts its retrograde motion westward. Tuesday, it resumes normal eastward (direct) movement. Saturn sets 1 AM.

Nightfall reveals the asteroids Ceres and Vesta still sharing Virgo with Mars. They continue to appear very close to each other. Astronomy resources provide finder charts. They set about 12:30 AM.

Neptune rises in Aquarius about 10 PM and remains up the rest of the night. Uranus rises at 11:33 PM in Pisces and also remains visible all night.

The twenty-five-day-old Moon rises in Taurus after 2 AM both nights. Tuesday's Moon lies close to the red star Aldebaran; Wednesday's waning crescent is found near the head of Scorpius.

Venus appears during civil twilight. It blazes fifteen degrees to the Moon's lower left. While the Moon appears about 18 percent illuminated, Venus seems ninety percent.

Mercury emerges eight degrees to Venus' lower left. The elusive planet is also quite bright and looks as if about two-thirds illuminated.

As appropriate for the racing season, two horses appear by midnight. The largest horse is, of course, Pegasus. The smallest is Equuleus. This dim constellation is easy to find. Pegasus flies upside down and is easily identified as a Great Square. Two thin chains sweep northward from the upper left. If one scans across the chain, binoculars expose a large hazy oval; this is revealed, in telescopes, to be the Andromeda Galaxy – about two and a half million light years distant. You can see it with the naked eye under rural skies. Pegasus' neck flows from the lower right corner and angles up. Equuleus is the small angular line of stars West of the Pegasus' nose. A globular star cluster, M 15, lies exactly halfway between Pegasus' nose and Equuleus. This too is easily seen in binoculars.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, July 18, through Sunday, July 20, written by Alan French.

The Moon reaches last quarter late Friday, so moonrise will be will after midnight and the evening skies will be nice and dark this weekend.

If you look high in the northwest around 10 pm you’ll spot one of the most familiar landmarks in the night sky – the Big Dipper. The Big Dipper is an asterism, a pattern of bright stars, and is part of the constellation Ursa Major, the Great Bear.

The star at the bend of the Dipper’s handle, second from the end, Mizar, is a well known double star. People with good eyesight should be able to spot its companion, Alcor. To the Arabs the pair was known as the “horse and rider.” The Mi'kmaq (or Micmac) natives of Canada knew Mizar as Chickadee, one of the hunters following the bear across the sky, with the four stars of the bowl marking the bear’s feet. Alcor was the pot being carried to cook the bear.

A telescope reveals that Mizar itself is a double star, with the stars too close together to be spotted by the eye alone.

Weather permitting there will be public star parties at Landis Arboretum beginning on Friday, July 18, and Saturday, July 19. Star parties begin at 10:00 pm this month. Members of the Albany Area Amateur Astronomers will set up a variety of telescopes to show guests views of star clusters, nebulae, galaxies, and double stars. Ask to see Mizar and its companion.

Saturn will be well placed for viewing, and its lovely rings are always a treat, especially if you’ve never seen them before. At least four of the planets moons should be visible.

For those interested, there will be a brief introductory program in front of the Meeting House starting at about 10:15 pm. It will include a brief tour of the prominent constellations, hints for getting the best views through the telescopes, and copies of Abrams Sky Calendar for August for each guest.

Star parties are free and everyone is welcome. We do, however, encourage guests to support our fine hosts, the Landis Arboretum, either through a modest donation or a membership.

Your can find directions to Landis Arboretum here. For an address, use 176 Lape Road, Esperance, NY. Once you reach Landis continue up Lape Road past the main farmhouse and parking area. Turn right at the “Star Party” sign, which will mark the driveway into the Meeting House field.

Star parties at Landis Arboretum are canceled if the skies are mostly cloudy. If in doubt, please call 374-8460 in the early evening to confirm.

The Dudley Observatory Skywatch Line for Wednesday, July 16th and Thursday, July 17th written by Louis Suarato.

Giuseppe Piazzi was born on July 16, 1746. Piazzi was an Italian priest, astronomer and author who discovered the first asteroid, Ceres. After establishing an observatory in Palermo, he supervised the Palermo Catalogue of stars, containing 7,646 entries. Piazzi discovered Ceres on January 1, 1801. At first, Piazzi thought Ceres was a star, until he noticed its movement against the background stars. He then thought it was a planet. Later, he settled on calling his discovery a comet, although he wrote “… it is not accompanied by any nebulosity and, further, since its movement is so slow and rather uniform, it has occurred to me several times that it might be something better than a comet.”

Ceres is the largest object in the asteroid belt, which is made up of rocky bodies found between Mars and Jupiter. Ceres is now categorized as a dwarf planet, a solar system body larger than an asteroid and smaller than a planet. Ceres is the smallest dwarf planet, having a diameter of 590 miles. Detection of water vapor by the Herschel space observatory has caused scientists to believe it may have an ocean beneath its surface. NASA’s dawn spacecraft is expected to arrive at Ceres in the spring of 2015, when it will provide the closest view of its surface. Wednesday night, Shining at magnitude 7.7, Ceres can be found in the constellation Virgo, approximately 7 degrees to the upper right of Mars. About 1 degree below Mars is Spica, Virgo’s brightest star. To the south, in Libra, is Saturn. The 71% illuminated, waning gibbous Moon rises at 11:05 p.m. in Pisces. Venus rises at 3:34 a.m. below Pisces. Mercury rises about an hour later and is about 7 degrees below Venus.

Wednesday, July 16th is the 20th anniversary of the first of 21 asteroids, major fragments of comet Shoemaker-Levy, to crash into Jupiter. It was the first time a collision between two significant solar system bodies was observed. Over the next six days, 21 impacts were observed, the largest coming on July 21st when a fragment was estimated to release the energy equivalent to 6 million megatons of TNT.

The Albany Area Amateur Astronomers welcome you to join them for public star parties at the Landis Arboretum in Esperance, NY this Friday and Saturday, July 18th and 19th. Viewing will begin at approximately 10 p.m.

This is the Dudley Observatory Skywatch Line for Monday and Tuesday, July 14th and 15th written by Joe Slomka.

The Sun sets at 8:32 PM; night falls at 10:41. Dawn breaks at 3:22 AM, ending with sunrise at 5:30.

As the sky darkens, two bright planets become visible. Mars appears in southwestern skies about a degree above the bright star Spica. This month, Red Planet becomes increasingly smaller and dimmer in our instruments because Earth is pulling away from its neighbor. Mars appears to pass Spica and head for Saturn; in mid-August the two planets share the same binocular view.

Saturn, the other visible planet, occupies Libra. In binoculars, Saturn’s off-white appearance distinguishes it from the star Zuben Elgenubi, two degrees away.

Nightfall permits views of the asteroids Ceres and Vesta, which share Virgo with Mars. These two bodies appear very close in telescopic views. They lie about three degrees below the star Zeta Virginis. Astronomy magazines, websites and apps provide observing charts.

Mars and the asteroids set before 1 AM, while Saturn lingers until 1:30 AM.

The eighteen-day-old Moon rises an hour before nightfall. It appears in Aquarius, seven degrees above the seventh magnitude planet Neptune, which rises a half-hour later. Fifth magnitude Uranus rises before Midnight in Pisces. Tuesday evening finds the Moon midway between Uranus and Neptune. All three remain up the rest of the night.

Brilliant Venus rises about 3:30 AM. Through binoculars or telescope, the planet appears about 89 percent illuminated. Mercury follows, rising after 4 AM about six degrees below and to Venus’s left. Zero magnitude Mercury lies eight degrees above the horizon, providing a challenge for observers to see the elusive planet 44 percent lit.

On March 24, 1993, three old friends were engaged in astronomical observation at one of the smaller telescopes on California’s Mount Palomar. Gene Shoemaker, his wife Carolyn, and David Levy, a well-known comet discoverer, were hunting for asteroids. Carolyn, scanning the photographs with a microscope, saw what looked like a “squashed comet.” Subsequent observations through larger telescopes revealed that the comet was broken into several pieces and orbiting Jupiter. Official emails enlisted observatories around the world. The Minor Planet Center at Harvard combined the results of those reports and announced that in July of 1994, Comet Shoemaker-Levy 9 (as it was officially named) would hit Jupiter. Twenty years ago on this coming Wednesday, the world witnessed the impacts on TV. Amateur astronomers with backyard telescopes could clearly see the impact scars. Dr Shoemaker had been saying for years that asteroids hit planets; now he was vindicated. Last year, an eleven thousand ton asteroid entered Earth’s atmosphere and exploded with the force of a half-megaton over the city of Chelyabinsk in Russia, causing damage and injuries.

This is Dudley Observatory’s Skywatch Line for Friday, July 11, through Sunday, July 13, written by Alan French.

Reaching Full early Saturday, a bright Moon will dominate the night skies this weekend. The Full Moon of July is known as the Buck Moon, since July is when the bucks grow new antlers. It is also known as the Thunder Moon, and as I write this a thunderstorm, common in July, is moving through.

While the bright moonlight will obscure the dimmer stars and the faint deep sky objects many star gazers seek, the brighter stars will stand out. If you look high in the east around 10:30 pm you’ll spot a bright star well above the horizon. This is Vega, the fifth brightest star in the night sky and the luminary of the small constellation, Lyra, the Lyre. A parallelogram of stars to its lower right and a single star to its lower left complete the pattern that outlines Lyra.

About 14,000 years ago our Earth’s axis pointed toward Vega, and it was the North Star. It will regain that crown approximately 12,500 years in the future. It also has the distinction of being the first star photographed. Its picture was taken in 1850 at Harvard Observatory using the 15-inch “Great Refractor,” which was first used in 1847.

Vega, like most of the bright stars in the night sky, shines brightly because it is a nearby neighbor, lying at a distance of 25 light years, meaning the light you see left the star 25 years ago.

If you look to the lower left of Vega you’ll see another bright star. This is Deneb, marking the tail of Cygnus, the Swan. It’s not hard to see the swan’s body stretching to the right or south, and wings stretching upward and downward one star to Deneb’s right.

To the lower right and farther away from Vega is a third bright star, Altair, which lies in the constellation Aquila, the Eagle. If you see two stars of about equal brightness, one to either side of it, you have the right star. Together Vega, Deneb, and Altair form a large asterism, or pattern of bright stars, known as the Summer Triangle.

While Altair is bright because it is also a close neighbor, lying just under 17 light years from us, Deneb is an extremely distant star. Its distance is uncertain, but the best estimate is 2,500 light years – 100 times farther away than Vega. It is bright because it is an exceptionally bright star, one of the most luminous known, shining 200,000 times more brightly than our Sun. If Deneb was at the same distance as Vega, 25 light years, it would be as bright as a gibbous Moon.

The Dudley Observatory Skywatch Line for Wednesday, July 9th and Thursday, July 10th written by Louis Suarato.

Wednesday, the 91% illuminated, waxing gibbous Moon rises around 5:41 p.m. EDT between the constellations Scorpius, below, and Ophiuchus, above. Later in the evening, Saturn will appear south of the Moon in the constellation Libra and Mars will appear west of Saturn in the constellation Virgo. Saturn’s largest moon, Titan, made the news recently with the discovery of a bright spot in the hydrocarbon lake Ligeia Mare. This “magic island”, as researchers are calling it, may be floating methane icebergs. The appearance of this feature is the first evidence of seasonal changes on Saturn’s largest moon. On Mars, NASA’s Mars Curiosity Rover celebrated its one Martian year anniversary, or 687 Earth days, on the red planet. NASA’s Opportunity rover also celebrated an anniversary, now having spent 10 years on Mars.

Rising with the Moon, to its east, is the constellation Cygnus. When you look at Cygnus through binoculars, you’ll see a multitude of stars. The reason is that Cygnus lies within the Milky Way. The dusty band of stars is an edgewise view of the galactic disk. Cygnus’ brightest star is Deneb, one of three stars that comprise the Summer Triangle. Within Cygnus is the Northern Cross asterism. Deneb marks the head of the Northern Cross. At the opposite end of the Cross is Albireo. Albireo is a 3.35 magnitude binary star. Binary stars consist of two stars orbiting common center of mass. Approximately 85% of stars are found in double or multiple systems. A small telescope will reveal that Albireo is one golden yellow, or topaz star, and a companion blue, or sapphire, star. Polaris, also known as the North Star, in Ursa Minor, is also a binary star system. Through a small telescope, one can see a small bluish star near its brighter companion. There are also multiple star systems consisting of three or more stars which are gravitationally bound to each other. An example of a multiple star system is Omicron Cassiopeiae. Omicron Cassiopeiae consists of three stars. The primary component is a blue-white giant with a mean apparent magnitude of 4.54. A more distant companion is an 11th magnitude yellow-white star.

Omicron Cassiopeiae is located between Cassiopeia’s brightest star, Shedir and the constellation Andromeda. Follow the lower point of Cassiopeia’s “W” about 5 degrees to locate Omicron Cassiopeiae.

Thursday, Venus rises at approximately 3:30 a.m. EDT. You may be able to see Mercury seven degrees below Venus, but be careful not to look directly into the glare of the rising Sun.


This is the Skywatch Line for Monday and Tuesday, July seventh and eighth written by Joe Slomka.

The Sun sets at 8:36 PM; night falls at 10:48. Dawn breaks at 3:12 AM and ends with sunrise at 5:25.

At Sunset, the ten-day-old Moon is the brightest object in the sky. By Civil Dusk, the Moon appears one-and-a-quarter degrees below Saturn. Tuesday evening, a fatter Moon appears to Saturn's lower left. The Moon sets at 2 AM Tuesday and 2:44 AM Wednesday.

Saturn, in Libra, is one of the few objects that shine through the lunar glare. Its rings are still stunning in a telescope. Mars, to Saturn's right, glows close to Spica, in Virgo. It appears in both binoculars and telescopes as a tiny red ball; Earth is pulling away from Mars, which daily shrinks.

The asteroids Ceres and Vesta are still visible above Mars in Virgo. On July 5th, both were apparently at their closest; now, they are slowly separating. Binoculars and amateur telescopes can capture the pair, under dark skies, with the aid of detailed finder charts from astronomy magazines. While they appear close, they are actually far apart; Ceres lies about 46 million miles behind Vesta. NASA's Dawn spacecraft studied Vesta in 2011 and 2012; now, Dawn is heading towards Ceres for a Spring 2015 rendezvous, during which the probe will orbit Ceres. Mars sets at 12:39 AM, while Ceres and Vesta do so at 1:20 AM.

Neptune rises in Aquarius at 11 PM. Uranus follows at 12:28 AM. Both are best detectible during pre-sunrise hours. Again, finder charts are available from various astronomical media.

Civil Dawn sees Venus rise at 3:27 AM, followed by Mercury at 4:14. Both are naked eye visible when higher shortly before sunrise. Venus appears 87 percent illuminated in our telescopes, while Mercury is about one-quarter lit.

Like planets and comets, asteroids (also called minor planets) have defined orbits about the Sun. Comets are ice and rock mixes, while asteroids are mostly rock. There are several types of asteroid. Some orbit between Jupiter and Mars, others accompany planets, and then there are interlopers from the far reaches of the solar system.

Vesta is the fourth minor planet to be discovered. It orbits the Sun every 3.6 years. Like the first three asteroids, Vesta was temporarily named a planet, until astronomers realized their small size. Vesta is the brightest, shining at magnitude 6.4. It can be seen in binoculars from a dark, rural site. Vesta currently inhabits the body of Virgo, the Maiden.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, July 4, through Sunday, July 6, written by Alan French.

The Moon reaches first quarter Saturday morning, making the July 4 weekend perfect for lunar observing. And on Saturday night we can enjoy a very close encounter between the Moon and Mars.

Look for the Moon, a bit less than half full, low toward the southwest as darkness falls on Friday night. Notice bright reddish Mars above and to the left of the lunar orb, about 12 degrees away (a fist held at arm’s length spans 10 degrees across the knuckles). By Saturday night the Moon’s eastward motion among the stars will have moved it very close to Mars, and the pair will be a lovely sight.

On Saturday Mars will be just above the Moon and only 21 arc minutes away – that’s less than the 30 arc minute (one half degree) diameter of the Moon! You can see it by eye, but it would be a pretty sight in binoculars or a low power telescope.

By Sunday night the Moon will have moved even farther eastward against the starry background, leaving Mars well to its west. On Monday evening the gibbous waxing Moon will pass within a degree of Saturn.

On any of these nights the Moon will be a lovely sight through even a modest telescope. Generally the lowest magnification provides the sharpest, most pleasing view, revealing a wealth of mountains and craters along the dividing line between bright sunlight and darkness. Even steadily held binoculars will reveal some of the larger craters.

Notice that the lunar surface is divided into two distinct regions, the brighter, rough highlands and the smoother and darker lunar seas or maria. The southern portion (bottom) is dominated by craters and mountains. (Many telescopes made for astronomy turn the image upside down, so south may be at the top.)

Look for a small, dark, round sea near the limb of the Moon. This is Mare Crisium, the Sea of Crises. It is just visible by eye alone and easily spotted in binoculars. It is 345 miles in diameter and was formed around four billion years ago.

The maria are plains of basalt formed by volcanic eruptions occurring from one to four billion years ago. They are less reflective than the material in the lunar highlands, and so appear dark. They cover about sixteen percent of the Moon’s surface, and the majority are on the side of the Moon visible from Earth.

The Dudley Observatory Skywatch Line for Wednesday, July 2nd and Thursday, July 3rd written by Louis Suarato.

The 23% illuminated, waxing crescent Moon rises at 10:30 a.m. Wednesday. As the sky darkens, and the Moon sinks toward the western horizon, Regulus, the brightest star in the constellation Leo, will appear about 14 degrees to the west of the Moon. You’ll find reddish Mars, shining at magnitude .23, above the southwest horizon in the constellation Virgo. That bright star, just 5 degrees to the left of Mars, is Virgo’s brightest star, Spica. Further south is golden Saturn in the constellation Libra. The separation between Mars and Saturn will decrease from 28 degrees to 12 degrees during July. To the east of Saturn, is the red supergiant star, Antares. At magnitude 1.05, Antares is Scorpius’ brightest star. Scorpius is the second-brightest constellation visible from mid-northern latitudes, second only to Orion. Jupiter is gradually becoming a memory as it hugs the western horizon after sunset.

Looking further east, just past the Milky Way, is the Teapot asterism within the constellation Sagittarius. The Milky Way gives the appearance of steam coming out of the teapot’s spout. An asterism is a group of stars within a constellation, or from multiple constellations, that form a pattern commonly identified as recognizable object. Other common asterisms include the Big Dipper within Ursa Major, the Keystone in Hercules, the Little Dipper in Ursa Minor, the Great Square of Pegusus, and the Summer Triangle across the constellations Cygna, Lyras and Aquila. Lesser known asterisms visible through binoculars and small telescopes include The Coathanger in the constellation Vulpecular, the Toadstool in Delphinius, and the Fish Hook asterism formed by Scorpius’ tail. Asterisms provide a way to star hop to other objects. For example, you can use the Keystone asterism in Hercules to find the glorious globular cluster, M13. You’ll find M13 between the two western stars of the Keystone.

Thursday morning, Venus rises at 3:25 a.m. in Taurus. Look for the Pleiades star cluster approximately 10 degrees above Venus. At 8 p.m. Thursday, our planet reaches aphelion, it furthest distance from the Sun for the year. At this time, Earth will be 94,506,462 miles from the Sun.

This is the Skywatch Line for Monday and Tuesday, June 30th and July 1st written by Joe Slomka.

The Sun sets at 8:37 PM; night falls at 10:53. Dawn breaks at 3:05 AM, ending with sunrise at 5:21.

As twilight darkens, the three-day-old Moon hovers low in the West. It is the brightest object in the sky and appears about twelve percent illuminated on Monday. Tuesday finds the thicker Moon five degrees below Leo's bright star, Regulus. The Moon sets after 10 PM.

Mars hovers high in the Southwest. Dusk reveals its characteristic red color. Through July, Mars approaches Spica, the brightest star in Virgo; it continues to dim and shrink in our telescopes. Mars sets at 1 AM. On July first, Mars is 93 million miles from Earth – the same distance as Earth is from the Sun. By Midnight, Scorpius is high. An interesting experiment is to compare the color of the star Antares with Mars. "Antares" means "Rival of Mars," because of their similar color. However, Mars is red due to its rusty soil, while Antares is red because it is an old, cool star.

Saturn brings up the rear, high in the South. Saturn continues to march westward in Libra; it also slightly dims and shrinks. Saturn sets at 2:26 AM.

At nightfall, asteroids Ceres and Vesta congregate about the star Zeta in Virgo. Both lie within one-and-half degrees of the star. On July 5th, these solar system members are at their closest – only 10 arc-minutes apart (one-third a Moon diameter). They can be seen through binoculars as well as telescopes. Observing charts can be found from magazines, websites and apps.

Neptune rises before Midnight and is best observed in Aquarius at Dawn. Uranus rises after Midnight and is apparent in Pisces. Charts can be found in various astronomical media.

Venus rises at 3:25 AM, but is best seen during Civil Dawn, when it is the brightest object in the eastern sky. Through binoculars or telescopes, Venus appears about 85 percent illuminated.

The Fourth of July is famous for fireworks. In the year 1054 Nature staged her own fireworks show. Chinese astronomers saw a new star in Taurus. Eyewitness accounts said it "shone like a comet." The "guest star" shone in daylight for 23 days and was visible nightly for a year and a half. Many textbooks remark that no one in Europe or the Mid East noticed it. North American Natives saw it and made rock carvings depicting it. Charles Messier made it the first in his list of false comet objects. We now know the Crab Nebula is the remnant of that star. It shone with the brightness of 500 million suns and produced a pulsar, a residue body that spins rapidly and emits regular radio pulses.

Clear Skies, Joe Slomka



This is Dudley Observatory’s Skywatch Line for Friday, June 27, through Sunday, June 29, written by Alan French.

The Moon is new early Friday, so this weekend will feature dark skies, ideal for star gazing. Dudley Observatory and the Albany Area Amateur Astronomers will take advantage of the moonless skies to host public star parties at two locations.

Dudley Observatory will hold a talk and star party at the Octagonal Barn in Delanson at 8:00 pm on Friday, June 27. The speaker will be Glenn Coilek, a PhD student at RPI. His talk is "Outflows and Shock Waves in Star-Forming Interstellar Clouds." If the skies are clear there will be a star party, with telescopes provided by Dudley Observatory’s Rising Star Interns and the Albany Area Amateur Astronomers, following the talk. The barn is located at 588 Middle Road, Delanson, New York 12053.

Weather permitting there will be public star parties at Landis Arboretum beginning at 10:00 pm on Friday, June 27, and Saturday, June 28. Members of the Albany Area Amateur Astronomers will set up a variety of telescopes to show guests views of star clusters, nebulae, galaxies, and double stars.

Saturn will be well placed for viewing, and its lovely rings are always a treat, especially if you’ve never seen them before. Its moons Titan and Rhea will also be easy to spot, and Dione and Tethys, which orbit closer to the planet, should also be visible.

For those interested, there will be a brief introductory program in front of the Meeting House starting at about 10:15 pm. It will include a brief tour of the prominent constellations, hints for getting the best views through the telescopes, and copies of Abrams Sky Calendar for July for each guest.

Star parties are free and everyone is welcome. We do, however, encourage guests to support our fine hosts, the Landis Arboretum, either through a modest donation or a membership.

Your can find directions to Landis Arboretum here. For an address, use 176 Lape Road, Esperance, NY. Once you reach Landis continue up Lape Road past the main farmhouse and parking area. Turn right at the “Star Party” sign, which will mark the driveway into the Meeting House field.

Star parties at Landis Arboretum are canceled if the skies are mostly cloudy. If in doubt, please call 374-8460 in the early evening to confirm.

The Dudley Observatory Skywatch Line for Wednesday, June 25th and Thursday, June 26th written by Louis Suarato

Charles Messier was born on June 26, 1730 in Badonviller, France. Messier was an astronomer devoted to discovering comets. While searching for a comet predicted to appear by Edmund Halley, Messier observed a fuzzy, comet-like object in the constellation Taurus. Realizing the object did not move relative to background stars, Messier sought to catalogue all objects that appeared to be comets but were “nebulae”. In doing so, Messier created a catalogue of 103 nebulae, or fuzzy objects that resembled comets, so other astronomers wouldn’t be confused. The first object, M1, was the Crab Nebula, in the constellation Taurus. The Messier Catalog remains an important tool for amateur and professional astronomers and contains the locations of 12 nebulae, 26 open clusters, 29 globular clusters and 42 galaxies.

Two of Messier’s deep sky objects that can be seen in the June night sky are the spectacular globular cluster, M3, located approximately 20 degrees west of Bootes’ brightest star, Arcturus. Discovered by Messier in 1764, M3 is a 6th magnitude object that joins M5 and M13 as one of the three brightest globular clusters in our sky. M3 is about 33,900 light-years away and contains a half million stars. Another Messier object is M101, the Pinwheel Galaxy, a face-on spiral galaxy located about 12 degrees west of the last star in the Big Dipper’s handle, Alkaid. The Pinwheel Galaxy is about 27 million light-years away and is 7th magnitude in brightness.

Jupiter appears only 7 degrees above the west-southwestern horizon at twilight and sets at 10 pm EDT. Mars can be found approximately 30 degrees over the southwestern horizon in the constellation Virgo, with Spica 10 degrees to its south. Saturn, in Libra, is to the south of Spica and Mars. The summer triangle refers to the stars Altair, in the constellation Aquila, Deneb in Cygnus, and Vega in Lyra. Look for the summer triangle rising over the eastern horizon as the sky darkens. Venus rises at 3:25 am Thursday. The New Moon occurs at 4:09 Thursday morning. The latest sunsets of the year occur at 8:37 pm Thursday, June 27th through July 1st.

The Dudley Observatory invites you to a Star Party on Friday, June 27 beginning at 8:00 PM, rain or shine, at the Octagon Barn in Knox, 588 Middle Road at the intersection of Beebe Road. Glenn Coilek, a PhD student from RPI, presents "Outflows and Shock Waves in Star-Forming Interstellar Clouds". Glenn studies star formation, which is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as "stellar nurseries" or "star-forming regions", collapse to form stars. Amateur astronomers and families are invited to bring binoculars and telescopes. Call (518) 618-5376 for more information.

Also, the Albany Area Amateur Astronomers invite you to join them for public star parties Friday, June 27th and Saturday, June 28th at the Landis Arboretum in Esperance, NY, weather permitting. Numerous telescopes will be available for guests to view planets and many Messier deep sky objects.

This is the Skywatch Line for Monday and Tuesday, June 23rd and 24th written by Joe Slomka.

The Sun sets at 8:37 PM; night falls at 10:54. Dawn breaks at 3 AM and ends with sunrise at 5:18. Since last Saturday's Summer Solstice, we have already lost one minute of daylight.

The darkening sky contains three bright planets. Jupiter is quite low on the western horizon. The giant planet will soon be lost in the Sun's glare and sets at 10:04 PM.

Mars is high in the southwestern sky. It steadily becomes dimmer and smaller in our telescopes. Observing surface features becomes difficult. Mars continues its westward trek towards Spica in Virgo. Mars sets at 1:23 AM.

Saturn is high in Libra. It is best observed before 10 PM, but the Ringed Planet will be visible until 2:55 AM.

Star-like asteroids Ceres and Vesta huddle within a degree of each other from now until July 17th. They lie about three degrees west of the star 79 in Virgo. These are challenge objects, since their motion relative to background stars reveal their true nature.

Comet Panstarrs continues to brighten; now at 7.6 magnitude, Panstarrs is 19 degrees high in the dim constellation of Leo Minor. It is about four degrees below the star 21 in Leo Minor, and six degrees above the star Mu in Leo. Most amateur telescopes and binoculars should be able show the comet. Panstarrs sets at 1:09 AM.

Neptune rises before Midnight in Aquarius. Uranus, in Pisces, enters the scene at 1:22 AM. Both are best seen between Astronomical and Civil Dawn. Finder charts are available from Astronomy magazines, websites and apps.

Venus emerges with the twenty-seven day-old Moon on Tuesday's Civil Dawn. They lie within two degrees of each other. The thin crescent Moon shines at -4.8 magnitude, while Venus glimmers at -3.9. In a telescope, Venus appears 84 percent illuminated, while the Moon shows only 8 percent. Wednesday morning finds the slimmer Moon to Venus' lower left.

The constellations we know come to us mostly from the Mesopotamians and Greeks. As previously mentioned, Arab scholars preserved these constellations and frequently gave the stars Arabic names. However, Arabic culture saw the sky differently. For example, although Ursa Major represents the Great Bear, the bear's feet and Leo Minor form a different constellation – the Gazelle.

The Gazelle leaps away three times westward from Leo, the Lion. The first leap is the Bear's hind feet: Alula Australis and Alula Borealis. The second leap is the other set of hind feet: Tania Australis and Borealis. The final leap is the bright front paw, Talitha. Alula Borealis is a red giant star, 70 times wider than the Sun and a thousand times brighter.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, June 20, through Sunday, June 22, written by Alan French.

Reaching last quarter on Thursday, a waning crescent Moon will rise well after midnight, leaving the evening skies nice and dark.

Saturn was once thought to be unique – the only planet with rings. It remains the only planet with rings visible through amateur telescopes, but Jupiter, Uranus, and Neptune also have rings, although they are very faint.

Astronomers have recently discovered that asteroid Chariklo has two dense, narrow rings. Chariklo is the largest confirmed asteroid in the outer solar system. Its orbit lies between Saturn and Uranus and it is 250km in diameter.

Galileo was the first to observe Saturn with a telescope, but he thought the rings were two moons, one on either side of the planet. In 1655 Christen Huygens, who had observed the planet with a telescope magnifying 50 times, suggested that Saturn was surrounded by a solid ring. It was another 200 years before James Clerk Maxwell correctly deduced that the rings were composed of many small particles orbiting Saturn. We now know the ring system is very complex and have gotten superb views of its fine detail from the Cassini spacecraft.

The ringed planet is now due south and highest just before 10 pm, when it will be 32 degrees above the horizon. This is the best time to catch a view of Saturn’s gorgeous rings, which are visible in any modest telescope magnifying about 30 times. A magnification of 60x, the maximum for many birding scopes, provides a better view. Saturn will be a feature target at June public star parties held by the Albany Area Amateur Astronomers.

Weather permitting, the Albany Area Amateur Astronomers, in association with New York State Parks, will hold a public star party in Grafton Lakes State Park beginning at 9:00 pm on Friday, June 20. If you arrive after dark, please use the winter entrance. For further information call Ray (658-3138) or Bernard (658-9144). If the skies are cloudy on Friday, the star party will be held on Saturday night, if the skies are clear. Call if in doubt.

Next weekend, June 27 and 28, there will be public star parties at Landis Arboretum. There will also be a talk and star party at the Octagonal Barn in Delanson on Friday, June 27. Look for details in next weekend’s Skywatch Line.

This is the Dudley Observatory Skywatch Line for Wednesday, June 18th and Thursday, June 19th written by Louis Suarato.

June 18 is the birth date of Allan Sandage. Born in 1926, Sandage co-discovered the first optical identification of a quasi-stellar radio source, or quasar. In 1960, using the 200-inch Hale Telescope, Sandage and Thomas Mathews identified a faint star-like object with a spectrum unlike any star. Quasars are the brightest and most distant objects in the known universe. A quasar’s luminosity can be 100 times brighter than our Milky Way galaxy. The luminosity of a quasar is derived from the energy emitted as its mass falls onto the accretion disk around a black hole. Quasars are billions of light-years away, and yet, can be seen from Earth! The brightest visible quasar that can be seen from Earth is 3C 273 in the constellation Virgo shining between magnitude 12 and 13. Quasar 3c273 is about 2.5 billion light-years away and can be seen with an 8-inch telescope approximately 5 degrees northwest of the star Gamma Virginis.

Wednesday evening, Jupiter sets about 1 hour and 45 minutes after sunset. As Jupiter is setting, and the sky darkens, Mars will appear about 35 degrees above the southwestern horizon in the constellation Virgo and Saturn can be seen above the southern horizon at approximately the same altitude. Virgo’s brightest star, Spica, will be 10 degrees from Mars and 23.8 degrees from Saturn. Moonrise occurs at 11:44 p.m. EDT. Look for Neptune rising with the Moon 13 degrees to its south. Venus rises at 3:28 a.m. with the Pleiades star cluster 7 degrees to its north.

The Moon will reach it Last Quarter phase on Thursday at 2:39 p.m. and rises at 1:02 a.m. Friday. Along the terminator of the Last Quarter Moon are Montes Alpes and Montes Apenninus. Montes Apenninus contains the highest mountain on the Moon, Mons Huygens. Mons Huygens is 18,046 feet above Mare Imbrium. Although it is the highest lunar mountain, Mons Huygens is not the highest point on the Moon. The highest point is located on a plateau on the far side of the Moon and is estimated to be 35,387 feet above the average lunar elevation.

The Dudley Observatory and Albany Area Amateur astronomers invite you to join them for a Star Watch on June 20th at the Deerfield Pavilion in Grafton Lakes State Park. In the event of cloudy skies, the Star Watch will be rescheduled for Saturday night.

This is the Skywatch Line for Monday and Tuesday, June 16th and 17th written by Joe Slomka.

The Sun sets at 8:36 PM; night falls at 10:53. Dawn breaks at 2:59 AM and ends with sunrise at 5:16.

As the sky darkens, three bright planets arch over the southwestern sky. Jupiter is westernmost and brightest; within a month, it will be out of sight. Jupiter sets about two hours after sunset; so observers should work quickly to get in last minute looks.

Mars is high in the southwest. Its distinctive red color distinguishes it from nearby stars. Like Jupiter and Saturn, it becomes dimmer and smaller in our eyepieces. Surface features become difficult to resolve. Mars lies about 11 degrees from Spica, Virgo’s brightest star, and sets at 1:46 AM.

Saturn glows high in the South. It lies within the constellation Libra, 23 degrees to Spica’s east. Saturn sets at 3:23 AM.

As night falls, asteroids Ceres and Vesta share Virgo with Mars. These asteroids huddle within a degree of each other, and both are within four degrees of the star 79 Virginis. The pair constitutes our challenge objects for the night.

Comet Panstarrs has moved out of Ursa Major and into the little-known constellation Leo Minor. Leo Minor forms a thin line between the Big Bear and the Big Lion. The seventh magnitude comet is brightening and should be visible in binoculars under dark skies. Panstarrs is located very close to the star 21 Leonis Minoris. Astronomy media provide observing charts.

Midnight finds the nineteen-day-old Moon rising in Capricornus. Its brilliance diminishes the grandeur of the Milky Way and nearby deep sky objects. Wednesday’s midnight shows the Moon moved into Aquarius. Wednesday’s Moon is about two-thirds illuminated and slightly dimmer.

Dawn sees the Moon high in the southwest, while eighth magnitude Neptune is about three degrees below our satellite on Wednesday morning. Dawn also witnesses Uranus rising in Pisces. Finder charts are available from astronomy magazines, websites and apps.

Venus rose at 3:28 AM, and, by Dawn, blazes in the East. It slowly closes in on the Sun. In telescopes, it appears about 82 percent illuminated.

Several dim but lovely constellations are sandwiched between brighter Pegasus, Aquarius and Cygnus. One of these is Delphinus, the Dolphin. It is found midway between Pegasus’ and Cygnus’ noses. It looks like a diamond with a tail and replicates a dolphin leaping out of the water.

There are two Greek myths about Delphinus. One states that covetous crewmen threatened Arion, a rich poet, while he was traveling. When he was flung into the sea, he was rescued by a dolphin, which carried the poet safely to the Greek coast.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, June 13, through Sunday, June 15, written by Alan French.

The Moon reached full very early Friday. The Full Moon of June is the Strawberry Moon, since strawberries are ripe and ready for picking this month. The name comes from the Algonquins. In Europe it is known as the Rose Moon.

The Moon rises at 9:02 pm in the south southeast on Friday, at 9:54 pm Saturday, and at 10:41 Sunday. Moonrise can be a very pretty sight, with the lunar orb appearing unusually large and often looking a lovely orange. With a good choice of foreground it can make an excellent photographic target.

Our Moon is rather unique. None of the other terrestrial planets have a significant Moon. Neither Mercury nor Venus have moons, and Mars has two tiny moons, Deimos and Phobos, which are most likely captured asteroids. They were both discovered by Asaph Hall in August, 1877. He was using the 26-inch Clark refractor at the United States Naval Observatory.

In Greek mythology Ares, the god of war, had two companions he took into battle. One was Phobos, panic, and the other was Deimos, terror. The Roman name for Ares is Mars.

From the surface of Mars Phobos appears about one-third the diameter of our Moon, and it looks smaller when seen near than horizon than overhead. An observer near the Martian polar regions would never see it. It orbits the planet in 7 hours and 40 minutes. Since it Mars rotates in one day and 40 minutes, the quick moving satellite rises in the west and sets in the east, and reappears only 11 hours after setting.

Little Deimos is farther away and only appears as a bright star in the Martian sky. It orbits once every 30 hours and takes almost three days to cross the sky from west to east. It does not rise again for close to three days.

Our Earth’s equatorial diameter is just over 7,900 miles, while our Moon’s diameter is 2,159 miles, making the Moon just over one-quarter the size of Earth. Its large relative size makes it unique in the solar system, and we are the only planet to have one large Moon. The gas giants all have more than one, and none approach one-quarter the diameter of the parent planet.

Jupiter has four large moons, Io, Europa, Ganymede, and Callisto. All are visible in even a modest telescope, appearing as stars near the planet and appearing roughly in a line. Saturn’s largest moon, Titan, is also an easy target for a telescope, and the next largest, Rhea, is fairly easy to spot.

This is the Dudley Observatory Skywatch Line for Wednesday, June 11th and Thursday, June 12th written by Louis Suarato.

As the Moon approaches its Full phase this week, and its brightness overwhelms the dimmer constellations, stars and deep sky objects, it may be a good time to draw your attention to some of the brighter celestial targets in the sky. The brightness of an object is a factor of distance, size and luminosity. This is often measured in “Apparent Magnitude”. Apparent magnitude is the brightness of a star, or other celestial body, as it appears from Earth. About 2,500 years ago, the Greek astronomer, Hipparchus, classified the brightest stars as first magnitude. The faintest stars, he classified as sixth magnitude. The lower the apparent magnitude, the brighter the object.

The brightest object, of course, is the Moon. The average distance of the Earth from the Moon is 238,900 miles. That is approximately 100 times closer than the next brightest and closest solar system body, Venus. With a diameter of 2,159.2 miles, our Moon is the fourteenth largest object in our solar system behind the Sun, planets, Jupiter’s moons Ganymede, Callisto and Io, and Saturn’s largest moon, Titan. The apparent magnitude of the Full Moon is -12.35. The Moon will reach its Full phase at 12 minutes after midnight, Friday. As the Moon is setting, Venus rises in the mid-dawn sky, shining at magnitude -3.40. Jupiter, dropping lower towards the sunset each day, is the next brightest object at magnitude -1.40. Mars, high above the southern horizon after sunset, shines at magnitude -0.09, while Saturn, to the southeast shines at magnitude .46. The brightest star in this season’s sky is Vega, at magnitude 0.00, which can be found in the constellation Lyra, above the eastern horizon. The next brightest star is Capella at magnitude 0.05. Catch it to the north of Jupiter and west of Cassiopeia before it sets around 10 pm. Follow the arc of the Big Dipper’s handle to Arcturus in the constellation Bootes, at magnitude 0.15.

The brightest Messier objects that can be viewed despite the Full Moon’s brilliance are M44, the Beehive Cluster at magnitude 3.1, located to the upper left of Jupiter in the constellation Cancer. Also look for M7, the Ptolemy Cluster, near the spout of the Teapot asterism in Scorpius, at magnitude 3.30. Closer to home, the man-made satellite, the International Space Station can shine as bright as magnitude -4.0 as its solar array reflects sunlight. Wednesday evening, look for the ISS to pass over our skies at 11:27 pm out of the northwest. Heavens-above.com lists this pass as magnitude -1.4.

This is the Skywatch Line for Monday and Tuesday, June ninth and tenth written by Joe Slomka.

The Sun sets at 8:32 PM; night falls at 10:48 Dawn breaks at 3:01 AM and ends with sunrise at 5:17.

After sunset, the Moon and four bright planets span the sky. The eleven-day-old Moon blazes high in the South. It is highest at about 10 PM. It’s brilliance washes out most dim deep sky objects, but not planets. The Moon inhabits Libra both nights; Tuesday evening, it lies four degrees below the planet Saturn.

Mercury is westernmost of the planets. By Civil Twilight, it is about two degrees above the western horizon. In a telescope, it appears about seven percent illuminated. This is tonight’s challenge object, since the observer must begin the hunt immediately after sunset.

Jupiter shines through the twilight. It too, sets quickly. Civil Twilight begins at 9:07; Jupiter is high enough in the southwest for observation of its cloud bands and moons. The giant planet sets at nightfall.

Mars is centered in the southern sky. It has slightly dimmed and shrunk over the past month. Exploring surface features is becoming difficult, due to the planet’s quickly dropping behind our faster Earth. Mars sets at 2:10 AM.

Saturn brings up the rear. As noted, it shares Libra with the bright Moon. However, Saturn is almost immune to the lunar glare. The giant planet and its famous rings never fail to astound beginners and star party guests. Saturn sets at 3:52 AM.

With the Moon setting about 3 AM, planet Neptune can be found in Aquarius, having risen after Midnight. Neptune is about eighth magnitude. Brighter Uranus, at sixth magnitude, rises an hour-and-a-half later in Pisces. Astronomy magazines, websites, and apps provide finding aids.

All the planets of the Solar System own a total of 172 moons, or satellites, of which Saturn has 62. Saturn’s largest moon, Titan, is also the brightest at eighth magnitude – within the ability of even small telescopes. Titan is second in size only to Jupiter’s moon, Ganymede; our Moon is third. Titan is unique is that it is the only satellite with a substantial atmosphere. It is about 1.5 times the pressure of Earth’s atmosphere. Nitrogen is the predominant gas, with a mix of hydrogen compounds. As a result, Titan’s atmosphere can be called “smog.” This smog hindered astronomers from observing its surface. When the space probe Huygens landed on Titan, it revealed river systems and lakes, much like Earth. However, Methane, not water, flows on these rivers. Titan’s clouds also rain Methane, just like earthly storms.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, June 6, through Sunday, June 8, written by Alan French.

We start the weekend with a lovely pass of the International Space Station on Friday night. The ISS will be gliding across the sky during twilight, with only the brightest stars and planets visible, but the bright space station should be easy to spot, especially as it approaches the highest part of its path.

The ISS times will be given in hours, minutes, and seconds, and are for Albany, but they should be close enough for anyone in the Capital District region. For more precise times, use Spaceweather's Zip Code based Flyby app.

The space station will first appear at 9:03:32 pm in the west southwest. (I often find I don’t spot it until a bit later when it is higher above the horizon, especially during twilight.) The ISS will reach its highest point at 9:06:51 pm when 77 degrees above the north northwestern horizon. At this altitude it will look essentially overhead. It will vanish in the northeast at 9:10:10 pm.

Reaching first quarter Thursday, a waxing gibbous Moon will dominate the night sky this weekend and will not set until after midnight. Although many amateur astronomers avoid moonlit nights, since its light obscures the faint deep sky objects they observe, the Moon is a worthy target for any telescope.

If you have even a modest telescope, take it out and enjoy craters and mountains on the lunar landscape once darkness falls. You’ll see the most detail along the terminator, the line separating light from darkness and now the sunrise line. Here shadows are long and features stand out in bold relief.

You may find the sharpest and most impressive views are at the lowest power. This is the eyepiece with the largest number on it. Usually it is a 25mm eyepiece. Divide the number on the eyepiece by the focal length of the telescope to get the power or magnification. (The focal length of the telescope is often written near the focuser. A 900mm focal length is pretty common.) Using an eyepiece of 25mm focal length in a 900mm focal length telescope gives a magnification of 36.

Although many telescopes brag about high powers, 450 or even 600 power, such magnifications are generally useless, providing dim, fuzzy views and making it hard to keep the Moon in view. Indeed our atmosphere often limits the useful magnification to 250 to 300 on even the best telescope.

The Albany Area Amateur Astronomers have an exhibit at the central branch of the Schenectady Public Library. It’s in the display case just past the shelves of newer books, so be sure to check it out if you’re at the library. The display runs through June.

The Dudley Observatory Skywatch Line for Wednesday, June 4th and Thursday, June 5th written by Louis Suarato

The 38% illuminated, waxing crescent Moon rises at 11:42 a.m. Wednesday. The Moon will reach its First Quarter phase on Thursday at 4:39 p.m. EDT. Mercury is elusive this month as it becomes lost in the Sun’s glare making its journey back towards our star. Wednesday after sunset, around 9 p.m., look for Mercury 7 degrees above the west-northwest horizon. Mercury makes a complete orbit around the Sun in 88 Earth days. Look for Mercury to appear on the other side of the Sun in mid-July, joining Venus in the early morning sky. Jupiter can be found to Mercury’s upper left, 20 degrees above the western horizon. Jupiter will fade from view at the end of this month, and will reappear in the morning sky in late August. Jupiter sets a few minutes after 11 pm. After sunset, Mars will appear left of the Moon, about 40 degrees above the southern horizon. When viewing Mars, you’ll notice its reddish hue. This is caused by oxidation, or rusting, of the iron minerals in the “Red Planet’s” soil. Mars sets at 2:39 a.m. Thursday. Saturn is to Mars’ lower left, over the southeastern horizon. Saturn’s rings are tilted 21 degrees toward Earth and the gap between the rings and planet can be seen through most telescopes. Saturn remains in the sky until dawn. As Saturn is setting in the west, Venus rises in the east. Venus’ rotation is opposite that of other planets, which means the sun rises in the west and sets in the east on this hellish planet.

June 5th is the birth date of astronomer John Coach Adams. Born in 1819, Adams was one of two astronomers who independently discovered the planet Neptune. Adams noticed irregularities in Uranus’ orbit and attributed it to the presence of another planet, whose gravity was affecting the inner planet. Although Adams’ calculations were performed in 1845, Neptune wasn’t visually discovered until September 24, 1846 by Johann Gottfried Galle.

This is the Skywatch Line for Monday and Tuesday, June Second and Third written by Joe Slomka.

The Sun sets at 8:28 PM; night falls at 10:39. Dawn breaks at 3:07 AM and ends with sunrise at 5:19.

The five-day-old Moon rose this morning and blazes in the Southwest by sunset. It sits between four bright planets that arch across the evening sky.

First magnitude Mercury becomes visible about 45 minutes after sunset. It lies low in the West, near the star cluster M-35. In telescopes or high-powered binoculars, Mercury appears about 19 percent illuminated. Mercury sets at 10 PM. Next week it disappears into the solar glare.

Jupiter, second in brightness to tonight’s Moon, glows to the right of our satellite. Jupiter is moving east; it forms a dogleg with Castor and Pollux this month. The giant planet sets after 11 PM.

Mars, to the Moon’s left, also moves eastward. Near the star Porrima in Virgo, the Red Planet heads toward Spica. It is highest at 8:47 PM, but best observed after twilight. Mars sets at 2:36 AM. The asteroids Ceres and Vesta, which also occupy Virgo, close in on each other near the star Heze. Astronomy magazines and websites provide observing aids to these members of the Solar System.

Saturn, unlike Jupiter and Mars, heads westward in Libra. But like fellow planets, it dims and shrinks slightly this month. Saturn’s rings are still very observable and a must-see for all sky watchers. Saturn sets at 4:21 AM.

June is a transition month. The Spring sky is setting and, by Midnight, summer constellations appear. The Milky Way, Scorpius, Sagittarius and Capricornus are prominent in the South. Aquarius, too, is up, and harbors Neptune, while Pisces hosts Uranus.

Venus rises during pre-dawn hours. By Dawn, it blazes brightly, but fairly low in the East. It is heading towards the Sun, rising later each day. It, too, dims and shrinks over the month.

When you are done observing Mars, turn your attention to the close star Porrima. The Latin name refers to the Goddess of Prophesy. The star lies midway between Spica, in Virgo, and Denebola, Leo's tail. Porrima is a double star. Both stars are nearly identical. They are about the same brightness, third magnitude, and the same mass, about 1.5 times the Sun. They are sun-like, but significantly brighter and warmer. Porrima and its companion are main sequence stars, fusing hydrogen into helium. Porrima was among the first double star systems discovered. Sir John Herschel calculated its orbit in 1833. They share a highly elliptical orbit, which make one cycle in about 169 years.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, May 30, through Sunday, June 1, written by Alan French.

Reaching new on Wednesday, a slender crescent Moon will return to the early evening sky this weekend. Look for it low toward the west northwest just as darkness falls Friday night. It will be fourteen degrees above the horizon at 8:30 pm and will set at 10:00 pm. By Saturday night it will be higher and seven degrees below brilliant Jupiter, with the bright star Procyon farther to its lower left. Sunday night will find it still higher and to Jupiter’s left.

Watch the crescent Moon as the sky darkens. You’ll soon notice you can see the entire Moon – with the portion within the bright crescent faintly illuminated. If you were on the side of the Moon visible from Earth, you’d see a bright, nearly full Earth in your sky. The faint light is sunlight reflected from our Earth. It is called earthshine, and it is also described as the “old Moon in the new Moon’s arms.”

From the Moon our Earth appears more than three and a half times the apparent diameter of the Moon as seen from here – it would span almost two degrees of sky. The Earth also reflects two and a half times as much light as the Moon, so it would be an impressive sight from the lunar surface.

The Moon is tidally locked to our Earth, so the same side always faces us. Because of its eccentric orbit, our view shifts a little, and we can actually see about 59% if the Moon over time. From the lunar hemisphere we see, our Earth is always in the sky, and goes through phases just like the lunar phases we see. The far side of the Moon, which also experiences day and night, never has the Earth in its sky.

Weather permitting the Albany Area Amateur Astronomers will hold public star parties at Landis Arboretum in Esperance beginning at 10:00 pm on Friday night, May 30, and Saturday night, May 31. At a star party club members set up a variety of telescopes to share celestial sights with guests. We look at nebulas, galaxies, star clusters, and double stars. The planets Mars and Saturn will also be visible. Mars is too far from Earth to reveal much detail right now, but Saturn’s beautiful rings are always a treat.

For those interested, there will be a brief introductory program around 10:15 pm near the Meeting House. There is no admission charge, but we encourage guests to support our fine hosts, Landis Arboretum.

You might wonder why we start so late. With the longer days of summer, combined with Daylight Saving Time, the skies are not completely dark until 10:00 pm. Without the shift to Daylight Saving Time we could schedule summer star parties starting at 9:00 pm.

Star parties are cancelled if the skies are mostly cloudy.

The Dudley Observatory Skywatch Line for Wednesday, May 28th and Thursday, May 29th written by Louis Suarato.

On Wednesday, there is a New Moon at 2:40 p.m. EDT. After sunset, look for Mercury about 10 degrees over the west-northwest horizon. Jupiter can be found approximately 20 degrees to Mercury’s upper left. Jupiter sets around 11:30 pm. Thursday evening offers an opportunity to see a very young, 2% illuminated, waxing crescent Moon below Mercury and Jupiter. As Mercury is setting, Mars will be 40 degrees over the southern horizon in the constellation Virgo. Saturn, in the constellation Libra, will be about 20 degrees over the southeastern horizon. Venus rises at 3:44 a.m. Thursday in Pisces.

The nights before, after and during the new Moon phase provide optimal conditions for telescopic viewing of planets and deep sky objects. Other factors include finding a location with minimal light pollution such as the Landis Arboretum used by the Albany Area Amateur Astronomers for their Star Parties. Celestial targets should also be located in constellations which are high above the horizons to prevent atmospheric interference. Deep sky targets in and near the constellations Ursa Major, Bootes, Canes Venatici, and Virgo fit the criteria for ideal locations at this time. The Whirlpool Galaxy, or M51, can be found about 3 degrees below the last star in the Big Dipper’s handle, Alkaid. M3, a globular cluster containing a half million stars, is between the constellations Bootes and Canes Venatici. Look to the west of Arcturus for this magnificent cluster. A visual trek through the constellation Virgo will reveal 11 Messier objects which are elliptical and spiral galaxies. Look to the upper right of Mars and above Leo’s tail star, Denebola for many of these galaxies.

This weekend, the Albany Area Amateur Astronomers will be providing views of these objects and more as they set up a variety of telescopes at the Landis Arboretum in Esperance, NY on Friday and Saturday nights. If you’re thinking of purchasing a telescope, a star party is an ideal place to try various types before making your decision. A brief tour of the constellations will be given as the sky darkens. Directions to the Landis Arboretum can be found at http://www.dudleyobservatory.org/AAAA/Directions.html. Star Parties may be cancelled if the sky is mostly cloudy.

This is the Skywatch Line for Monday and Tuesday, May 26th and 27th written by Joe Slomka.

The Sun sets at 8:22 PM; night falls at 10:29. Dawn breaks at 3:15 AM, and ends with sunrise at 5:22.

As the sky darkens, four bright planets appear. Mercury is the westernmost. It is low and about 12 degrees high. Several nearby stars are about as bright. So, identify Mercury by binoculars and telescope; it should look like a ball, one-third illuminated. Mercury sets at 10:16.

Jupiter is much brighter and higher in the Southwest. Ordinary binoculars make identification easy. As the sky darkens, an observer can see several of its moons, even in ordinary binoculars; telescopes enhance the view. Jupiter sets about 11:30 PM.

The Red Planet Mars lies due South at civil twilight. It is still large enough for views of its surface features. Mars, in Virgo, glows near the bright star Porrima. Ceres and Vesta, two of the first asteroids to be discovered, share Virgo with Mars. These challenge objects are within five degrees of the star Heze. Finder charts are available in astronomy magazines and websites. Mars sets after 3 AM.

Saturn is moderately high in the eastern constellation of Libra. Saturn is now past Opposition; this means that observers can examine the famous rings for nearly the whole night.

Eight magnitude Comet Panstarrs still traverses Ursa Major. After nightfall, the comet is near the star Chi, which forms a joint in the Bear’s rear leg. This comet should be visible to observers in rural areas. It remains up all night.

A twenty-eight-day-old Moon lies low at 4:45 AM, Tuesday. This is a very old Moon, only two percent illuminated. It is quickly washed out by the rising Sun. Wednesday finds the Moon officially “New,” which means that it is lost in the Sun’s glare.

About Midnight, the constellation Scorpius lies due South and high enough for it to rise above the tree line. Its brightest star, the Lucida, is Antares. The Greek name means "Rival of Ares," the Greek version of the Roman god Mars. Antares is one of the brightest stars in the northern sky. It is one of only two bright supergiant stars; the other is Betelgeuse. Antares is truly a giant star. Its diameter is 600 million miles, beyond Jupiter's orbit. Antares lies about 600 light years away; only Betelgeuse is closer. This star is nearing the end of its life. It is slightly variable, and will, one day, blow itself up as a supernova. In 1970, Antares was the first star proven to emit radio waves.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, May 23, through Sunday, May 25, written by Alan French.

Amateur astronomers and casual sky watchers may have a nice surprise this weekend - several experts are predicting a strong meteor shower on Saturday morning, May 24, with the peak activity sometime between 2 and 4 am. Since it’s a Saturday morning on a long weekend, being up during these hours is a bit less of a chore than usual.

The shower is associated with debris from Comet 2009P/LINEAR and the predicted peak is ideally timed for residents of North America and Canada.

As comets approach the Sun their gases are heated and released into space. This frees up many tiny grains of rock, and some larger pebbles and stones. This debris continues to orbit the Sun along the comets path, but spreading out as time passes.

When our Earth passes through one of these comet debris trails, we get a meteor shower. The meteors from the familiar Perseids of August are debris from Comet Swift-Tuttle. These bits of rock, traveling at speeds of from 7 to 45 miles per second as they enter our atmosphere, compress and heat up the air ahead of them, their outer layers are melted away, and we see a meteor streak across the sky.

Four experts predict four differing peak times for this new shower, 2:29 am, 3:00 am, 3:21 am, and 3:40 am, and three different rates, less than 200 per hour, more than 100 per hour, and 100 to 400 per hour. If any of them have it right it should be a nice show, making it worth watching the sky between about 2 am and 4 am Saturday morning, May 24th (after midnight Friday). Peak activity is expected to be fairly sharp, perhaps extending over an hour or so. There is, of course, a chance it will be a dud, or maybe even better than expected, and it is worth seeing what happens in person. They've done a good job predicting good years for the annual Leonid shower. It won’t hurt to check the sky occasionally after darkness falls Friday night.

The meteors can appear anywhere in the sky, so look in the direction where the sky is darkest or you have the clearest view. Their paths will all point back toward a point, the radiant, in the inconspicuous constellation Camelopardalis, which sits close to the Little Dipper, hence the shower would be the Camelopardalids. The radiant is not far from Polaris, the North Star. With the radiant in the northern sky, meteors will be visible all over the sky.

The Dudley Observatory Skywatch Line for Wednesday, May 21st and Thursday, May 22nd written by Louis Suarato.

The Moon reaches its Last Quarter phase at 9 am on Wednesday and will set at 12:45 pm. Five bright planets remain visible in the evening and morning skies. After sunset, Mercury can be seen about 13 degrees above the west-northwestern horizon. Mercury will reach its greatest eastern elongation on May 25th. Jupiter can be seen to Mercury’s upper left, approximately 27 degrees over the western horizon in Gemini. The distance between the two planets is 25 degrees and closing. By month end, Jupiter and Mercury will close to within 20 degrees and share the twilight sky with a thin crescent Moon. Images from the Hubble Space Telescope have revealed that Jupiter’s Great Red Spot is shrinking. In the 1800’s, astronomers determined the Great Red Spot to be 25,500 miles in diameter. In 1979, images from Voyager 1 and 2 helped estimated the giant planetary storm to be 14,500 miles across. Recent Hubble images reveal the Great Red Spot is now 10,250 miles across. Jupiter’s Great Red Spot transits the gas giant at 8:11 pm Wednesday night.

As Mercury is setting, Mars is high above the southern horizon in the constellation Virgo. Mars’ retrograde motion ends on Wednesday when it appears to be moving east to west against the background fixed stars. Saturn is lower on the southeastern horizon in the constellation Libra. At an average distance of 885,904,700 miles from the Sun, Saturn is the farthest planet from Earth visible to the naked eye. Saturn rotates once every 10.5 hours, spinning faster than every planet except Jupiter.

The 42% illuminated, waning crescent Moon rises at 1:53 am Thursday in the constellation Aquarius. Venus rises at 3:52 am in the constellation Pisces. Before Venus’ appearance, the International Space Station will sail over our skies. Look for the ISS to appear directly out of the star Arcturus above the western horizon and continue northeasterly through Ursa Minor and Cassiopeia.

The Dudley Observatory invites you to join them for an Octagonal Barn Star Party on Friday, May 23rd at 8 pm. The Octagonal Barn is located at 588 Middle Road in Delanson, NY. For those living further east, the Albany Area Amateur Astronomers will be hosting their monthly Star Watch also on May 23rd at 9 pm Grafton Lakes State Park in the Deerfield Pavilion parking area.

This is the Skywatch Line for Monday and Tuesday, May 19th and 20th by Joe Slomka.

The Sun sets at 8:15 PM; night falls at 10:18. Dawn breaks at 3:25 AM and ends with sunrise at 5:28.

After sunset, Jupiter becomes the brightest object in the Southwest. By Twilight’s end, Jupiter is only sixteen degrees high. An observer must work quickly. Jupiter sets before Midnight.

Mars, next brightest, appears to Jupiter’s left. It remains close to the star Porrima, in Virgo. Mars shares Virgo with the asteroids Ceres and Vesta. Astronomy media provide finder charts to these tiny members of our Solar System. Mars sets at 3:30 AM.

Mercury is the third brightest planet visible, at zero magnitude. It shines low in the West, amid stars that are about as bright. Mercury is best identified through telescopic observation. It appears about half illuminated. Mercury sets after 10 PM.

Saturn is also up, low in the East. By nightfall, Saturn is high enough for examination. While its rings are the most famous feature, Saturn is host to 62 moons. Titan, its largest, should be visible in most amateur telescopes. It appears to Saturn’s left. Saturn is best studied at Midnight, when it is about due South.

Comet Panstarrs travels through Ursa Major, the Big Bear. It lies about seven degrees beneath the lower left star in the Big Dipper, and a degree-and-a-half from the star Chi. The comet, so close to Polaris, doesn’t set, and is best viewed after nightfall.

The Moon rises in Aquarius after Midnight. It becomes officially at Last Quarter on Wednesday morning.

Venus rises at 3:37 AM in Pisces. By civil Dawn, it appears ten degrees high in the East. Telescopes or high-powered binoculars reveal it to be about three-quarters illuminated.

One of the astronomical clichés is that Jupiter’s Great Red Spot has been continuously examined for centuries. While true, the Spot has been known to change. For example, it is not exactly red now, but closer to a pale color; new astronomers have difficulty finding it. When measured in the 1800’s, the storm was 25,000 miles wide. In 1979, the Voyager spacecraft imaged it at 15,500 miles. In 1995, British astronomer John Rogers measured it at about 12,500 miles and also reported that wind speeds are increasing. The Great Red spot now blows 300 miles-per-hour winds, up from 250. Like an ice skater, it spins faster as it gets smaller. Recent Hubble Telescope images now reveal that it is about 11,000 miles wide. The cause for this shrinkage is unknown.

This is Dudley Observatory’s Skywatch Line for Friday, May 16, through Sunday, May 18, written by Alan French.

A waning gibbous Moon rises at 10:18 pm Friday, 11:12 pm Saturday, and 12:20 am Monday morning. The Moon will reach last quarter on Wednesday.

If you look toward the south at 10:00 pm you’ll see bright reddish Mars 44 degrees above the horizon. Look for a bright star below and to the left of Mars, about 15 degrees away. (A fist held at arm’s length spans 10 degrees across the knuckles.) This is Spica, the brightest star in the constellation Virgo, the Maiden.

Spica is the fifteenth brightest star in the night sky and lies at a distance of 250 light years. When the light entering your eye left Spica, American colonists were protesting British taxation. Its name is derived from the Latin for “Virgo’s ear of grain.”

Spica is actually a close binary system with the stars orbiting each other once every four days. They are much too close together to be seen as two stars with a telescope, but changes in their detailed spectrum reveals the duplicity. Because Spica lies near the ecliptic, the apparent path of the Sun across the celestial sphere, the Moon can sometimes pass in front of or occult Spica. Observations then suggest it may have three more stellar companions, making it a system of five stars.

Return your gaze to Mars and look for a bright reddish star well to the red planet’s upper left. It will be 33 degrees away. The is Arcturus, the brightest star in Bootes, the fourth brightest star in the night sky, and the brightest star in the sky’s northern hemisphere.

Arcturus lies 37 light years from Earth. The name means “Bear Watcher,” and the star follows Ursa Majoris, the Great Bear across the sky. Although the stars in our night sky appear fixed they are moving through space. Some, especially nearby stars, have moved noticeable distances since humans started paying careful attention. Its proper motion has moved Spica about one-half degree, the apparent diameter of the Moon, in the past thousand years.

While the constellation Virgo is fairly inconspicuous, the pattern of Bootes, the Herdsman is easy to trace in the sky. Simply look for a pattern of stars looking like a kite or ice cream cone stretching upward and slanting toward the left from Arcturus.

This is the Dudley Observatory Skywatch Line for Wednesday, May 14th and Thursday, May 15th written by Louis Suarato.

On May 14th, 1973, NASA launched “Skylab One”, the United States’ first space station. Skylab orbited Earth for six years and included a workshop and solar observatory which logged about 2,000 hours of scientific and medical experiments. Skylab also confirmed the existence of the Sun’s coronal holes. Skylab orbited Earth 2,476 times before burning up in the atmosphere in 1979. The International Space Station remains in orbit and returns to our skies this week. Look for the ISS to emerge out of the western horizon Thursday morning at 4:31 am and travel low eastward, passing close to Venus.

The Full Flower Moon occurs Wednesday at 3:16 p.m. EDT. Look for the Full Moon to rise around 8:11 pm. The Full Moon provides a good opportunity to view the large crater, Tycho, in the lunar southern highlands. Tycho is estimated to have been created 108 million years ago. This large crater is more than 54 miles in diameter and is surrounded by peaks rising as high as 17,000 feet. A binocular or small telescope view of Tycho will give you a view of the rays and ejecta emanating from the crater. You will notice the rays spreading out toward the east, south and northwest, but none toward the west.

As the Sun is setting and the Moon is rising, look to the west for Mercury about 10 degrees over the horizon. As the sky darkens, look approximately 7 degrees to the Moon’s upper right for Saturn. A telescope will reveal Saturn’s largest moon, Titan, to the ringed planet’s upper right. Higher and further south is Mars in the constellation Virgo. Mars will reach its highest point in the sky at 10:00 pm, when it is about 44 degrees above the southern horizon. At that time, Jupiter will be about 20 degrees high over the western horizon. Jupiter’s moon, Europa, disappears behind the planet at 9:45 pm Wednesday, and Io follows Europa at 30 minutes past midnight. Venus rises in Pisces at 4 am. Binoculars or a telescope will provide a view of Uranus just 1 degree to the upper left of Venus.

This is Dudley Observatory’s Skywatch Line for Friday, May 9, through Sunday, May 11, written by Alan French.

Saturday, May 10, is National Astronomy Day. It will be celebrated at miSci, the Museum of Innovation and Science, on Nott Terrace Heights. There will be indoor astronomy activities, planetarium shows, and a chance to win a telescope. Weather permitting there will be solar observing through safe, properly filtered solar telescopes, provided by the Albany Area Amateur Astronomers and Dudley Observatory.

Museum admission is $6.50 for children from 3 to 12, $9.50 for those over 12, and $8.00 for senior citizens (65 and older). Admission to a planetarium show is $5.00. Other Astronomy Day activities are included with admission.

A waxing gibbous Moon will dominate this weekend’s night sky. Look for Mars near the Moon on Saturday night and again on Sunday night. Mars will be closest to the Moon on Saturday night.

Saturn reaches opposition early Saturday. Opposition simply means the ringed planet is opposite the Sun in the sky. The planet is highest and due south just before 1am in the morning. At 10 pm you’ll find it twenty degrees above the southeastern horizon. Its lovely rings are visible in any telescope magnifying about 30 times, as is its brightest Moon, Titan, appearing as a star near the planet.

On Friday night at 10 pm Titan will be south southwest of the planet, or below and to the right. By Saturday night Titan will be west southwest of the planet, and by Sunday its orbital journey will have taken it almost due west of Saturn. Many telescope flip or invert the view of the sky, so take the changed orientation into account.

Unlike Jupiter, which sports four large moons visible in any telescope and many more that are beyond the reach of most amateur telescopes, several more moons around Saturn come into view with larger telescopes. Rhea is fairly easy and so are Tethys and Dione. Iapetus is not difficult, but is almost two magnitudes brighten when it is on the western side of the planet than when to the east. It is tidally locked so that one face always faces Saturn, and one hemisphere is much darker than the other. Mimas and Enceladus are challenging targets for experienced observers, as is Hyperion.

Planetarium programs and apps generally show the positions of Saturn’s moons, and can be configured to show the same orientation as your telescope.

This is the Dudley Observatory Skywatch Line for Wednesday, May 7th and Thursday, May 8th written by Louis Suarato

This week’s sky provides the opportunity to see five bright planets. Mercury will be the most difficult, located about 15 degrees above the Sun. Look low on the west-northwestern horizon for Mercury after sunset. Recent investigations of data obtained from NASA’s Messenger spacecraft, which has been orbiting Mercury since 2011, have revealed that the innermost planet had experienced volcanic eruptions for billions of years. Mercury was originally thought to be bone dry, but analysis of bright reflective material, believed to be pyroclastic ash, indicates volcanic activity derived from a core of molten rock.

As Mercury is setting, Jupiter will be high above the western horizon in the constellation Gemini. Thursday evening, at 7:41 p.m., Jupiter’s moon Io begins to transit the planet. A half hour later, Callisto disappears behind Jupiter. At 8:47 p.m., Io’s shadow begins its transit. Callisto reappears at ten minutes past midnight. To the south of Jupiter, the 58% illuminated, waxing gibbous Moon will be below the constellation Leo and 6 degrees below its brightest star, Regulus.

Mars, now shining at magnitude -.83, can be seen in Virgo to the lower left of the Moon, just 2 degrees from the binary star Porrima, also known as Gamma Virginis. Saturn will be lower on the horizon, rising in the constellation Libra. Saturn reaches opposition on Saturday and can be seen until setting at dawn. While Saturn is setting in the west, Venus will be rising at 4:30 a.m. in Pisces. A telescopic view of Venus will reveal a two-thirds illuminated disk. Venus will be three-quarters illuminated by the end of the month.

Saturday, May 10th is Astronomy Day! The Dudley Observatory, located at the Museum of Innovation and Science (miSci) in Schenectady, will be celebrating Astronomy Day by hosting a solar star party from noon to 4 pm. Join Dudley Observatory staff and the Albany Area Amateur Astronomers as they offer solar views of sunspots and prominences with a variety of safe, filtered telescopes.

This is the Skywatch Line for Monday and Tuesday, May fifth and sixth. Written by Joe Slomka

The Sun sets at 8 PM; night falls at 9:54. Dawn breaks at 3:49 AM and ends with sunrise at 5:43.

As the sky darkens, the six-day-old Moon blazes in the southern constellation of Cancer. The Moon turns First Quarter tomorrow, which means that it is half illuminated. It sets at 1:18 AM Tuesday, and 1:50 AM Wednesday.

Jupiter shines to the Moon’s upper right. It is slowly moving eastward in Gemini’s waist. Telescopic observers can witness Jovian moon Ganymede’s shadow cross the planet’s face at 1008 PM Monday. Jupiter sets after Midnight.

As twilight deepens, Mars appears to the Moon’s lower left in Virgo. The Red Planet lies near the star Porrima. Although Mars was at opposition last month, Mars is still quite large and bright in our telescopes. Surface features are still visible; Mars remains up almost all night.

Saturn is also up by Dusk; however, it is best observed after nightfall, when it is about sixteen degrees high in the eastern constellation of Libra. Though not as bright as Mars or Jupiter, Saturn stands out among the stars, and is worthy of observation for its famous rings. Saturn also remains up almost all night.

Mercury is very low in the West. It presents a challenge to see the tiny, but brilliant planet so close to the horizon.

Comet Panstarrs is now traveling between the handle of the Big Dipper and the bottom of the Dipper. At eighth magnitude, most amateur telescopes should be able to capture this visitor to the inner Solar System. With the Moon setting shortly after midnight, Panstarrs can be found six degrees below the star Alcor, which forms the bend in the Dipper’s handle.

Venus rises during Dawn, and, by civil twilight, is high enough to be easily spotted. It is the brightest object in eastern skies. It has shrunk slightly in our telescopes, but blazes with its surface two-thirds illuminated.

This May presents two meteor showers. One shower is visible in early May. Astronomers are anticipating an extra shower later in the month. Pre-dawn hours of Monday, Tuesday and Wednesday see the arrival of the annual Eta Aquariid meteor shower. Experts expect a rate of 50 per hour for the duration. However, Aquarius is low on the horizon; and, its meteors are best seen in the southern US. The Capital District can see a few long, graceful “earthgrazers,” which skim the upper atmosphere from the east-southeast. The Eta Aquariids are related to the Orionid shower of October. Both showers result from the Earth running into the stream of debris from Halley’s Comet.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, May 2, through Sunday, May 4, written by Alan French.

Having reached new on Tuesday, a crescent Moon will grace the evening sky this weekend. Moonset is at 11:20 pm Friday night, 12:04 am Sunday morning, and at 12:43 am Monday morning. The Moon reaches first quarter very late this coming Tuesday. Any telescope will reveal a wealth of lunar detail.

Next Saturday, May 10, is National Astronomy Day. It will be celebrated from Noon to 4:00pm at miSci (formerly known as the Schenectady Museum) on Nott Terrace Heights. There will be indoor astronomy activities, planetarium shows, and a chance to win a telescope. Weather permitting there will be solar observing through safe, properly filtered solar telescopes, provided by the Albany Area Amateur Astronomers and Dudley Observatory.

For safe solar viewing, telescopes must be fitted with special filters designed specifically for viewing the Sun. A white light solar filter fits over the front of the telescope reflecting most of the light, and only allowing 1/100,000 of the visible light to pass through into the telescope. It also eliminates the invisible but harmful ultraviolet and infrared light. (Some telescopes, especially older ones, have a solar filter that goes over the eyepiece. These are NOT safe and should never be used. The concentrated light and heat at the eyepiece can crack the filter and allow the Sun’s concentrated light into your eye, causing permanent eye damage. It’s a dark filter, usually labeled “Sun.” It should be thrown away.)

White light solar filters allow safe views of sunspots, which are relatively small, cooler dark areas on the Sun. They also show plages, which are hotter, small brighter patches. The number and size of visible sunspots varies.

A second type of filter, the H-alpha solar filter, is more complex and expensive. It allows only a very narrow slice of light through the telescope – the red of glowing hydrogen. They also eliminate the ultraviolet and infrared light. These filters nicely show solar prominences – huge eruptions of hydrogen. In white light filters, prominences are invisible because they are much fainter than the rest of the Sun. Viewing the Sun in their prominent red color makes the prominences visible.

Seen against the Sun’s disk, prominences look like dark threads, and are called filaments. When along the edge of the Sun, they appear as red clouds extending out into space. Many are low, but some extend well away from the Sun, forming long tendrils and loops. Occasionally parts of these clouds of hydrogen appear completely detached from the Sun, hanging in space away from the Sun’s limb.

Museum admission is $6.50 for children from 3 to 12, $9.50 for those over 12, and $8.00 for senior citizens (65 and older). Admission to a planetarium show is $5.00. Other Astronomy Day activities are included with admission.

This is the Skywatch Line for Monday and Tuesday, April 28th and 29th written by Joe Slomka.

The Sun sets at 7:52 PM; night falls at 9:41. Dawn breaks at 4:03 AM and ends with sunrise at 5:52.

As the sky darkens, Jupiter is the brightest object visible, high in the southwest. Telescopic observers can witness the moon Europa cross the giant planet’s face at 9:54 Monday night. Europa’s shadow follows at 12:28 Tuesday morning. Europa ends its transit, leaving Jupiter’s face, at 12:36 AM Tuesday. Jupiter sets about 1:07 AM.

Mars appears in Libra, as twilight deepens. The Red Planet remains up most of the night. Mars is still quite large and bright in our telescopes about two degrees below the star Porrima. Surface maps and other aids can be found in astronomy magazines, websites and apps. The asteroids Ceres and Vesta are also at their brightest. These star-like bodies are also at their brightest; they hover around the star Zeta in Virgo. They pose a challenge for the observer to identify them out of the stellar myriad about them. Mars sets after 5 AM.

Comet Panstarrs will be easy to find these nights. It is now located less than a degree from the last star (Alkaid) in the Big Dipper’s handle. From a dark rural site, the comet could be seen through binoculars; telescopes increase the odds of finding it. Being so close to Polaris, the North Star, Panstarrs doesn’t rise or set; as long as it is dark, the comet will be visible all night long for the next couple of days.

Saturn rises in Libra about an hour before nightfall. By midnight, it is high enough for observation of its famously beautiful ring system.

Neptune rises before Dawn; followed by Venus an hour later.

Venus appears a little smaller than Saturn, and about two-thirds illuminated.

Sky watchers may recall the total eclipse of the Moon, two weeks ago. Such eclipses usually come in pairs; so does this one. The Moon turns “New” at 2:14 Tuesday morning. It set before the Sun Monday afternoon, and appears very low on the southwestern sky after Tuesday’s sunset. A skilled astronomer can find the sliver of Moon less than one degree above the western horizon. The second eclipse of this cycle is an Annular Solar Eclipse. This is when the Moon fails to fully block out the sunlight. The eclipse is visible from New Zealand, Australia, Japan and Asia.

Clear Skies, Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, April 25, thru Sunday, April 27, written by Alan French.

The dark skies make this a good weekend to watch the “secret” X37-B space plane cross high overhead. The X37-B is an unmanned, remotely controlled reusable spacecraft belonging to the U.S. Air Force. When crossing high in the sky, it appears as bright as the stars in the front of the Big Dipper’s bowl.

On Saturday night the X37-B will first appear at 9:54 pm coming up from the western horizon. It will be highest at 9:56:32 when 72 degrees above the northwest horizon. (At this altitude, it will seem almost overhead.) Here it will be moving into the Earth’s shadow and fading from view.

If you are looking west, the X37-B will rise straight up into the sky, passing just to the right of Gemini, and its luminaries Castor and Pollux, and the brilliant planetary interloper, Jupiter. The space plane will fade from view as it approaches to bottom of the Big Dipper’s bowl.

The pass Sunday night will be earlier and will cross most of the sky before entering the Earth’s shadow and fading from view. It will come up from the western horizon just after 8:57 pm, and will be highest at 9:00:20. At its highest it will be almost overhead. It will move into the Earth’s shadow at 9:02:40 when 17 degrees above the eastern horizon.

If you are looking west, the X-37B will travel upward about midway between brilliant Jupiter and bright Capella, to Jupiter’s right. After passing its highest point it will travel through the bowl of the Big Dipper, and will fade from view as it enters the Earth’s shadow after gliding through kite-shaped Bootes.

Weather permitting; the Albany Area Amateur Astronomers will hold public star party at Landis Arboretum in Esperance at 8:00 pm on Friday and Saturday, April 25 and 26. A variety of telescopes will be set up by club members to provide guests with views of star clusters, nebulae, galaxies, double stars, and other celestial sights. Mars and Jupiter are now visible in the evening sky.

Star parties are open to all and there is no admission fee, although we encourage attendees to make a donation to our fine friends and hosts, Landis Arboretum.

Star parties last at least an hour and usually go much longer if the skies are clear. You are welcome to stay as long or as briefly as you like. Be sure to dress warmly. It feels 20 to 30 degrees colder when you are standing under clear night skies. Having extra warm clothing on hand is better than being uncomfortable.

For directions to Landis Arboretum see this link. The star party will be canceled if the skies are mostly cloudy.

This is the Dudley Observatory Skywatch Line for Wednesday, April 23rd and Thursday, April 24th written by Louis Suarato

The 35% illuminated, waning crescent Moon sets at 1:34 p.m. Wednesday, and rises as a thinner 28% illuminated crescent Moon at 3:16 a.m. Thursday. As the skies darken Wednesday evening, evening, look to the western horizon for the Hyades and Pleiades open star clusters before they set. The constellation Orion will be setting to the left. Jupiter can be found above Orion in the constellation Gemini, while Mars will be located approximately 30 degrees above the southeastern horizon in Virgo. Saturn follows Mars, rising around 9:30 p.m. in Libra. Saturn’s rings are tilted 22 degrees toward Earth. Bright, magnitude -3.71 Venus joins the crescent Moon in the pre-dawn sky after 4:45 a.m. Thursday for a beautiful celestial view and photo opportunity.

With the Moon absent from the sky after sunset, take the opportunity to view some deep sky objects visible with small telescopes. Ursa Major, or the Big Bear, contains the well known asterism, The Big Dipper. The Big Dipper is easily identifiable directly overhead in April’s night sky. Galaxies M81 and M82 can be found just northwest of the Big Dipper’s bowl. Both galaxies can be seen within a one degree field of view. M81 is a spiral galaxy about 12 million light years away. M81 was discovered in 1774 by Johann Elbert Bode and is sometimes referred to as Bode’s Galaxy. M81 is the largest galaxy in the M81 Group which contains 34 galaxies in the constellation Ursa Major. M82 is a starburst galaxy undergoing a high rate of star formation. M82 is believed to be interacting with M81, which is causing the starburst activity.

The Dudley Observatory and Albany Area Amateur Astronomers invite you to join them for public star parties on Friday, April 25th and Saturday, April 26th at the Landis Arboretum in Esperance, NY. A variety of telescopes will be set up for viewing the heavens. Club members will provide views of nebulae, star clusters, galaxies, double stars, planets (when visible), and other interesting celestial objects. Star Parties are canceled if the skies are mostly cloudy. Directions to the Arboretum can be found at http://www.dudleyobservatory.org/AAAA/Directions.html

This is the Skywatch Line for Monday and Tuesday, April 21st and 22nd written by Joe Slomka.

The Sun sets at 7:44 PM; night falls at 9:30. Dawn breaks at 4:17 AM and ends with sunrise at 6:03.

As the sky darkens, Jupiter, in Gemini, is the first and brightest object to appear. It glows high in the southern sky. After nightfall, telescopic observers can see the Jovian moon Io crossing the planet’s disk; its shadow exits the planet first at 9:39, followed by Io itself at 9:54 PM. Jupiter sets at 1:30 AM.

Mars, in Virgo, is also visible in the twilight sky. Although Mars has passed Opposition, it is still very big and bright, and ideally placed for all-night observation. Medium sized telescopes will permit views of Martian surface features. Astronomy magazines, websites and apps provide observing aids. The Minor Planets, also called asteroids, Ceres and Vesta join Mars in Virgo. Both lie within five degrees of the star Zeta. These pose a challenge for the viewer.

Saturn rises at nightfall; by midnight, it is high enough for observation. It appears as a cream-colored bright object in Libra. Almost any telescope will show its rings, but larger instruments reveal them in greater detail.

The Last Quarter Moon rises at 2 AM in Capricornus; Wednesday, it rises in Aquarius.

Neptune rises about two hours later, and shares Aquarius with dazzling Venus. In powerful binoculars or telescopes, Venus appears about as large as Saturn and about two-thirds illuminated.

Comet Panstarrs also poses a challenge for the sky watcher. Panstarrs is an automated telescope that scans the sky for asteroids that threaten Earth. It also finds comets as a byproduct of its sky patrols. At 10 PM, Panstarrs is found in the constellation Bootes. It is bright enough for medium-sized telescopes. It can be found about three degrees from the star Lambda in Bootes on Monday night, and 2 degrees on Tuesday evening. Observers should try for it before the Moon’s glow overwhelms the asteroid.

Observers who stay up for the pre-dawn hours Tuesday may see meteors streaking from the East. This is the annual Lyrid meteor shower. Like most meteor showers, the Lyrids are litter left over from passing comets; as these specs of dust enter our atmosphere, they burn up in a fiery trail. This meteor shower has been continuously observed for over 2600 years. The shower is linked to Comet Thatcher and appears to originate near the bright star Vega in the constellation Lyra. Typically, between ten and twenty meteors are seen per hour. However, this year, the Last Quarter Moon’s brilliance will obscure the smaller and fainter Lyrids.

Clear Skies

Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, April 18, through Sunday, April 20, written by Alan French.

The full Moon was eclipsed last Tuesday morning. Alas, the skies were not clear along most of the east coast, including our area. There are, however, many fine photographs of this eclipse on the web. You can find some in the Spaceweather Real Time Eclipse Gallery here. Ignacio Diaz Bobillo has created a fine time lapse video of the eclipse, which you can enjoy here.

We get to a chance to see another lunar eclipse on October 8, but it will reach totality less than an hour before the Moon sets, and as morning twilight is brightening the sky.

Saturday was named dies Saturni by the Romans, meaning “Saturn’s Day.” Sunday and Monday were derived from “Sun’s Day” and “Moon’s Day.”

We have two interesting passes of the International Space Station (ISS) this weekend. During both you can watch the station move into the Earth’s shadow and fade from view. The times are given in hours, minutes, and seconds, and are for Schenectady, but they should be close enough for anyone in the Capital District and surrounding region. The ISS looks like a bright star gliding across the sky.

On Friday night the ISS will rise up from the northwestern horizon at 9:29:36. It will be highest just before 9:33 when 46 degrees above the north northeastern horizon, and will move into the Earth’s shadow and begin fading from view 23 seconds later. Its path will take it above the familiar “W” of Cassiopeia, very close to Polaris, and through the bowl of the Little Dipper. It will move into the Earth’s shadow when passing below the end of the Big Dipper’s handle.

The Sunday night pass will be higher and brighter. The station will first appear at 9:29:32 rising up from the west northwestern horizon. It will be highest just before 9:33 when 74 degrees above the southwestern horizon, and will move into the Earth’s shadow 21 seconds later and gradually fade. As it crosses the sky it will pass through the rough pentagon of stars, including brilliant Capella, marking Auriga, above brilliant Jupiter in the constellation Gemini, and past the head of Leo the Lion. It will move into the Earth’s shadow as it passes thru the hindquarters of Leo. How much farther can you follow it before it vanishes from sight?

This is the Dudley Observatory Skywatch Line for Wednesday, April 16th and Thursday, April 17th written by Louis Suarato.

As the skies darken after sunset on Wednesday, you’ll find Jupiter about 60 degrees above the west-southwestern horizon between the Gemini twins. Mars, just past opposition and closest to Earth in 2014, will be rising above the east-southeast horizon in the constellation Virgo. The 97% illuminated, waning gibbous Moon rises around 9:20 p.m. in Libra. Look for Saturn less than 2 degrees to the Moon’s lower left as it rises. By 3 a.m. Thursday, Saturn will be less than a degree from the Moon. Venus rises at approximately 5 a.m. Thursday in Aquarius.

On Wednesday, there will be a bright International Space Station pass over our region. Look for the ISS at 9:27 p.m. coming out of the northwestern horizon. The Space Station, now carrying six crew members and traveling at 17,500 miles per hour and orbiting Earth once every 92 minutes, will continue through Cassiopeia before disappearing into Earth’s shadow near Draco at 9:32.

On Thursday, at around 10:18 p.m., Jupiter’s largest moon, Ganymede, emerges from behind the planet’s eastern limb. At 12:06 a.m., Ganymede disappears behind Jupiter’s shadow and reappears at 3:29 p.m. EDT.

The Dudley Observatory and Albany Area Amateur Astronomers invite you to join them for a star party at the Octagonal Barn in Knox, NY on Friday, April 18th at 7:30 pm. At each Octagonal Barn Star Party, an interesting and informative presentation is given inside the barn along with light refreshments. If the sky is clear, guests are encouraged to view a variety of celestial objects through telescopes provided by amateur astronomers. Guests are encouraged to bring binoculars and telescopes as well. Check the Dudley Observatory’s website at www.dudleyorbservatory.org for details on the speakers at each party. Directions can be found on the website as well. If the Knox location is inconvenient, the Albany Area Amateur Astronomers will also be hosting a Star Party at Grafton Lakes State Park on Friday at 7:30 pm.

This is the Skywatch Line for Monday and Tuesday, April 14th and 15th by Joe Slomka.

The Sun sets at 7:36 PM; night falls at 9:18. Dawn breaks at 4:31 AM, ending with sunrise at 6:14.

As the sky darkens, the Moon and Jupiter attract our attention.

Jupiter is high in Gemini. Binocular watchers can witness the Jovian moon Io disappear behind the giant planet at 10:06 Monday night, and reappear at 1:38 AM Tuesday. Telescope users can see Io’s shadow marching across Jupiter at 10:32 PM Tuesday. Jupiter sets before 2 AM.

Mars lies about six degrees above the Moon. Although the Red Planet reached Opposition last week, Tuesday finds it closest for this apparition. It will be over 57 million miles from Earth. The minor planets Ceres and Vesta accompany Mars in Virgo. Both asteroids reach Opposition tonight and are most convenient to observe. They are small and challenging objects that require good observing skills.

Saturn rises in Libra after nightfall, and, by Midnight, is high enough for observation. Saturn’s luminosity, due to its clouds and rings, outshines the bright stars Spica and Arcturus.

Dawn witnesses the rise of Venus, moderately high in the East, and Mercury, to Venus’ lower left. Venus is dazzling. Mercury is bright, but more challenging to find.

Our Moon is Monday’s main attraction. It rises before sunset and remains up until sunrise. It becomes the Full “Pink” Moon at 3:42 AM Tuesday. After midnight Monday, the Moon experiences an eclipse by Earth’s shadow. The event begins at 1:58 AM as the Moon begins to enter the shadow. It is difficult to notice the shadow until it covers a large part of the lunar surface. Totality begins at 3:06 AM, when the Moon enters the darkest part of the shadow. Greatest Eclipse takes place at 3:46 AM - the midpoint. Totality lasts for 79 minutes, ending at 4:25 AM, when the lunar edge reemerges into sunlight. The Partial phase ends with the entire Moon illuminated at 5:33 AM.

No special equipment is needed. Dress warmly and find a comfortable chair. If you have binoculars, they help enhance the views. Sky watchers should note whether the Moon has a red tint. This is the result of sunlight being bent around Earth’s atmosphere; viewers are seeing the light of sunrises and sunsets. The Moon may appear dark if there is a lot of dust in Earth’s atmosphere; large volcano eruptions play a part. Since a Lunar Eclipse is the result of Earth blocking the Sun, an astronaut on the Moon would see a total Solar Eclipse.

Clear Skies
Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, April 11, through Sunday, April 13, written by Alan French.

Reaching first quarter last Monday and headed toward Full early this coming Tuesday; a waxing gibbous Moon will brighten the weekend’s night sky.

Jupiter continues to dominate the southwestern sky as darkness falls. Jupiter will grace our evening night sky for some time yet, but by the end of June it will be quite low in the western sky after sunset, and will be too close to the Sun to see in early July.

Jupiter is the largest planet in our solar system and fifth from the Sun. It is the innermost of the gas giant planets, and takes almost twelve years to make one trip around the Sun. Because of its distance, it moves slowly amongst the stars, taking approximately one year to move through each zodiacal constellation.

No planet in our solar systems turns on its axis faster than Jupiter, which completes one rotation in a little less than ten hours. Its fast rotation causes it to bulge at the equator. A modest telescope easily shows the planet is a bit out of round – wider at the equator than the distance between the poles.

When I was in grade school, Jupiter was known to have 12 moons. The brightest four were discovered by Galileo back in 1610, and are visible in any telescope. The remaining moons are much fainter, and the next discovery wasn’t until 1892, when E.E. Barnard discovered Amalthea with the 36-inch James Lick telescope, then the largest refractor in the world. Seven more moons were discovered photographically between 1904 and 1951. Since then sensitive searches from Earth and observations by spacecraft have brought Jupiter’s known retinue up to 67 moons.

The weekend features the annual Northeast Astronomy Forum, known to many simply as NEAF, and billed as “American’s Premiere Astronomy Expo.” It is held at Rockland Community College in Suffern, New York, only two to three hours from the Capital District region.

NEAF features fine speakers, more than 100 vendors and manufacturers showing off and selling astronomy equipment, programs for beginners, and a solar star party, where safe views of the Sun are provided by some of the finest solar telescopes on the planet. The doors are open from 8:30 am to 6:00 pm on Saturday and from 10:00 am to 5:00 pm on Sunday. Admission is $25 for one day and $45 for both. For more information visit their web site. It’s a fun excursion if you have an interest in amateur astronomy.

This is the Dudley Observatory Skywatch Line for Wednesday, April 9th and Thursday, April 10th written by Louis Suarato

The 72% illuminated, waxing gibbous Moon rises at 2:10 p.m. EDT on Wednesday. As the skies darken around 7:30, look for the brightest star in the constellation Leo, Regulus, to the lower left of the Moon. On Thursday night, the Moon and Regulus will be 6 degrees apart. Later this month, on or before April 21st, NASA’s LADEE (Lunar Atmosphere Dust Environment Explorer), that has been orbiting the Moon since October 6, 2013, will crash onto the lunar surface as it exhausts its remaining fuel. The impact crater created by LADEE’s high speed crash, will be examined by the Lunar Reconnaissance Obiter, NASA’s other probe circling the Moon. While you’re looking at Leo, do some galaxy hunting. Below and left of Regulus are the galaxies M95, a barred galaxy, and spiral galaxy M96. Further to the left and below are the spiral galaxies M65 and M66.

Below Leo, look for reddish Mars and blue Spica, rising in Virgo. Mars reached opposition on April 8th, and now shines at magnitude -1.5. About 15 degrees above Mars is the elliptical galaxy, M49. Saturn follows Mars as it rises at 10 p.m. in Libra. Scientists, using data obtained from the Cassini spacecraft, have recently determined that Saturn’s small moon, Enceladus, has a Lake Superior sized sea beneath its icy surface. The presence of a sub-sea could explain the geysers spouting from the moon seen on images previously taken by the Cassini spacecraft.

The pre-dawn sky features Venus as it rises at 4:40 a.m. in the constellation Aquarius and shines at magnitude -3.84. A few weeks ago, at the Lunar and Planetary Science Conference 2014, scientists presented evidence indicating Venus may be geologically active. Images taken by the European Space Agency’s Venus Express spacecraft show “bright transient spots” which appear to be active volcanoes. If true, Venus joins Earth, Jupiter’s moon Io, Saturn’s moon Enceladus, and Neptune’s moon Triton, as having volcanoes or cryovolcanoes. A cryovolcano erupts cold or frozen gases such as water, ammonia or methane.

This is the Skywatch Line for Monday and Tuesday, April seventh and eighth by Joe Slomka.

The Sun sets at 7:28 PM; night falls at 9:08. Dawn breaks at 4:46 AM and ends with sunrise at 6:25.

The First Quarter Moon dominates the darkening sky and appears moderately high in the Southeast. The half-lit Moon inhabits Cancer both nights. However, the Moon’s brilliance washes out the “Beehive” star cluster that also graces Cancer. The Moon sets at about 3 AM on both days.

Jupiter lies higher above the Moon, in Gemini. Monday evening, binocular observers can witness the Jovian moon Io reappear from behind Jupiter; they can also see, through their telescopes, Io’s shadow exit the face of the giant planet at 11:43 PM Tuesday.

Mars rises at sunset and sets at sunrise. The Red Planet appears in Virgo, just above the bright star Spica. Mars is at Opposition on Tuesday evening. This means that Mars is in a direct line through Earth and to the Sun. Opposition is the best time to observe any planet, but Mars is always special. A good telescope with moderate powers can show actual surface features. Astronomy magazines and websites provide Martian surface maps. Mars’ northern hemisphere is now experiencing its six-month summer, with its polar ice cap tilted in our direction. Observers can track the polar ice cap disappearing. Ice on Mars is frozen carbon dioxide gas; so, Martian ice does not melt; it turns into gas. Opposition does not mean that Mars is closest; Mars is actually closest to Earth on April 14th, when it is 57.4 million miles away. Mars orbits the Sun in about two years; the next two oppositions will be closer, but lower on the horizon and more difficult to see. Mars has two moons, Phobos and Deimos. These are challenge objects for astronomers who have larger telescopes, high powers and detailed star charts. If one does not have a telescope, one can still see Mars. The Curiosity rover, still active on Mars, routinely sends back pictures of Martian terrain; the Mars Reconnaissance Orbiter also beams high altitude pictures of Mars. Both are available on NASA websites.

Saturn, by Midnight, is high enough in Libra for observation of its glorious rings.

Venus rises at Dawn, and by civil dawn, is high enough for observation. Venus appears half-illuminated in a telescope.

The gas giant planet Neptune lies four degrees to Venus’ east and represents another challenge for the observer.

Mercury rises at 6 AM and is quite low on the eastern horizon.

Clear Skies
Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, April 4, through Sunday, April 6, written by Alan French.

The Moon reaches first quarter early Monday, so a waxing crescent Moon will be visible in this weekend’s evening sky. The Moon now rides high in the sky, so this is the perfect time to explore the lunar landscape. Any telescope will nicely reveal a wealth of craters and mountains, and even binoculars will reveal some detail. The terminator – the line dividing the sunlit portion of the Moon from darkness – is now the line of the sunrise, marching steadily across the lunar landscape as we move toward full. The moon does not set until after midnight.

For the naked eye sky watcher, the Moon will be near bright Jupiter on Saturday night, and the pair will be even closer together on Sunday night.

The International Space Station (ISS) returns to the evening sky on Saturday night, and during this pass and the one Sunday night the space station will move into the Earth’s shadow and fade from view, with Sunday’s disappearance higher in the sky than Saturday’s.

On Saturday the ISS will first appear moments after 8:42 pm coming up from the south southwestern horizon. (I often find I don’t spot the ISS until it has risen a bit higher in the sky.) It will be highest just after 8:45 when 31 degrees above the southeastern horizon, and will move into the Earth’s shadow and start to fade from view about 10 seconds later.

Its path will take it below the hind quarters of Canis Major, the Big Dog, never rising very high into the sky and continuing toward the southeast.

On Sunday, the ISS will first appear at 9:29:19 pm rising up from the west southwestern horizon. The ISS will be highest at 9:32:21 pm when 58 degrees above the northwestern horizon, as it moves into the Earth’s shadow and slowly disappears from view.

Its path will bring it up along Orion, between Jupiter and reddish Aldebaran, and just past bright Capella in Auriga. It will fade from view as it leaves the sunlight just after passing Auriga.

Mars rises at 7:34 pm in the east southeast and transits and is due south and highest at 1:12 am. Its disk now appears 15 arc seconds across and is almost 42 degrees above the horizon when it transits. The next few weeks are our best chance to search out the elusive features of the red planet with a telescope. Look for dark areas and a small polar cap

The Dudley Observatory Skywatch Line for Wednesday, April 2nd and Thursday, April 3rd written by Louis Suarato.

On Wednesday, after sunset, the 11% illuminated, waxing crescent Moon will be approximately 30 degrees above the western horizon. As the sky darkens, the Pleiades star cluster will appear about 10 degrees above the Moon. Higher in the southwest, you’ll find Jupiter in the constellation Gemini. Mars rises in Virgo at 7:51 p.m. EST. Saturn rises in Libra at 11:30 p.m. and Venus rises Thursday morning at 4:45.

Star clusters are groups of stars that are gravitational bound. These clusters can be distinguished by size, age, quantity of stars, and chemical composition of the stars within the cluster. The two types of star clusters are Open and Globular. Open star clusters range in age up to a few tens of millions of years old, and consist of tens to hundreds of thousands of stars. Globular star clusters are concentrations of extremely old stars billions of years old comprised of several million stars. An example of a globular cluster is M3 in the constellation Canis Venatici. You can locate M3 by looking approximately 12 degrees above Arcturus, the brightest star in the constellation Bootes. Arcturus can be found by following the “arc” of the Big Dipper. An example of an open cluster is the Hyades. The Hyades, in the constellation Taurus, is the nearest open cluster to our solar system and is easily recognizable by its “V” shape. The age of the stars within the Hyades star cluster if estimated to be 625 million years old. On Thursday night, after sunset, some of the 3rd and 4th magnitude stars of the Hyades star cluster will be occulted by the 19% illuminated, waxing crescent Moon. Taurus will be above the western horizon Thursday night. On Thursday evening, around 10:40 p.m. EDT, the dark limb of the Moon will occult the 3.8 magnitude star Delta 1 Tauri. The occulted star will reappear about 10:57 p.m. inside the lit portion of the Moon near the terminator. The bright star 2 degrees to the left of the Moon is Aldebaran.

This is the Skywatch Line for Monday and Tuesday, March 31st and April First by Joe Slomka.

The Sun sets at 7:20 PM; night falls at 8:58. Dawn breaks at 5 AM, and ends with sunrise at 6:37.

The one-day-old Moon shines low in the southeast on Monday night, presenting a challenge to the observer, since the Moon is a 2 percent illuminated thin crescent. Tuesday’s Moon is higher, brighter and fatter in Aries, making it easier to spot. The Moon sets before 10 PM.

Jupiter is higher and brighter than the Moon on Monday night; it blazes in the Southwest in Gemini. On Monday, telescopic observers can see the Jovian Moon Io disappear at 9:48 PM and observe the Great Red Spot, a giant storm, at 10:52 PM. Jupiter sets before 3 AM.

Mars rises at 8 PM. The Red Planet appears brighter than Spica, the brightest star in Virgo. Mars lies about five degrees above Spica. Besides Mars, two asteroids, Ceres and Vesta, huddle around the star Tau in Virgo. Astronomy magazines, websites and apps provide observing guides. Mars remains up the rest of the night.

Saturn, in Libra, joins the scene by rising at 10:39 PM. Its rings can be observed through almost any size telescope, but larger instruments reveal the rings in all their glory. Both Mars and Saturn are best watched in the hours before Sunrise.

Venus appears in Capricornus after rising at 4:48 AM. Under moderately powered binoculars or telescopes, it blazes at -4.3 magnitude and appears over half-lit.

Since Jupiter and Saturn are visible simultaneously, comparisons are in order. Both are gas giants - planets composed mostly of gas. Jupiter is larger; Saturn is about a third of Jupiter's mass. In telescopes, Jupiter's colored bands signify very active weather systems; one storm, the Great Red Spot, has been continuously observed for centuries. Saturn's weather appears more subdued, with occasional faint features. Saturn's ring system is easily visible from Earth. Jupiter's rings are observable only from space-borne telescopes. Both planets' 120 moons account for most of the Solar System’s total. Four of Jupiter's moons appear in binoculars, while Saturn's satellites can only be spotted through a telescope. Jupiter’s moon Io is the most volcanically active moon in the Solar System, while Europa, Ganymede and Callisto may have oceans beneath their icy surfaces. Saturn’s moons Enceladus and Titan are geologically active, spurting ice fountains. Titan is the only moon to have an atmosphere; its atmosphere contains methane, rather than oxygen. Titan also has vast lakes of liquid methane on its surface.

Clear Skies

Joe Slomka

This is Dudley Observatory’s Skywatch Line for Friday, March 28, through Sunday, March 30, written by Alan French.

The Moon reaches new on Sunday so the weekend’s night sky will be dark and moonless. A slender crescent Moon rises in the east at 6:56 am Saturday, only 47 minutes before sunrise.

The Milky Way, a hazy band of light formed by the thousands of distant stars that lie along the plane of our galaxy, is nicely visible under dark skies. With no interference from the Moon, people with access to skies free of light pollution can trace its path across the sky. In the summer, we are looking inward, toward the center of our galaxy, so the Milky Way is bright and prominent. In the winter, we are looking outward, so the band of light is more subtle. It’s still fun to trace its path across the sky.

If you go outside around 10 pm, you’ll find the Milky Way stretching upward from the southern horizon, tipped slightly to the right or west. The gentle glow passes just to the left or east of Sirius, the brightest star in our night sky, and to the right of bright Jupiter, now lying near the knees of the Gemini twins. It then continues upward through the rough pentagon of stars outlining Auriga, the Charioteer, high about the western horizon. It grows very faint after passing through Auriga.

If you now look toward the north, you’ll see the Milky Way rising up from the horizon a bit west of due north, and slanting a bit toward the west. It can be followed through the “W” of Cassiopeia, but again fades as it approaches Perseus, the Rescuer of Andromeda. Exploring the Milky Way with binoculars will reveal many stars too faint to see by eye, and some rich star clusters.

If you are up early on Sunday morning there is a nice pass of the International Space Station (ISS) over the Capital District. The ISS will appear brighter than any of the stars in the pre-dawn sky as it glides across the sky.

The ISS will first appear just after 5:39 am coming up from the northwestern horizon, and will be highest at 5:46:36 when 68 degrees above the north-northeastern horizon. It will vanish below the east southeastern horizon at 5:46 am. Its path will take it through to bowl of the Big Dipper, past the bowl of the Little Dipper, and through Cygnus, the Swan. The main stars of Cygnus as known as the Northern Cross.

By the time you see the ISS, three new astronauts, two Russian and one American, should have arrived at the station aboard a Soyuz rocket.

The Dudley Observatory Skywatch Line for Wednesday, March 26th and Thursday, March 27th written by Louis Suarato

Charles Messier was a French astronomer, who, as a comet hunter, was fooled by other celestial deep sky objects that resembled comets. Messier created a catalogue in 1771 to note these objects and prevent them from being mis-categorized during future observations. Early Spring is optimal for viewing these objects, when they all can be viewed in a single night. The original Messier Catalogue contained 45 objects. The final edition contains 103 objects. The catalogue contains 27 open clusters, 29 globular clusters, 6 diffuse nebulae, 4 planetary nebulae, and 40 galaxies (24 spiral, 8 elliptical, 4 barred, and 4 lenticular). There are several one-of-a-kind objects in the catalog including 1 supernova remnant, 1 Milky Way patch, 1 double star, and 1 asterism. On March 28th & 29th, beginning at 7 p.m., the Dudley Observatory will be hosting a Messier Marathon at their Octagonal Barn dark sky site. A Messier marathon is an attempt, usually organized by amateur astronomers, to find as many Messier objects as possible during one night. Observatory staff and volunteers will be leading the effort to view as many objects in the sky Friday night into the early morning. The address and directions to this special Star Party can be found on the Dudley Observatory web page under “Messier Marathon”.

Wednesday evening, Mars rises in the constellation Virgo at 8:31 p.m. EDT. Look 4.5 degrees north of Mars for Virgo’s brightest star, Spica. The reddish planet and bright blue star provide a beautiful contrast of colors. At that time, Jupiter will be 55 degrees above the southwestern horizon. Jupiter’s Great Red Spot transits the planet at 11:30 pm. Saturn rises in Libra at 10:55 pm. A photo taken by NASA’s Cassini spacecraft has led some scientists to believe that Saturn’s largest moon, Titan, may have waves breaking on its methane lakes. “If correct,” the scientists say, “this discovery represents the first sea-surface waves known outside of Earth.” Venus rises at 4:52 a.m. Thursday. The 15% illuminated, waxing crescent Moon will be 3.6 degrees to the upper left of Venus. The Moon reaches perigee, its closest distance to Earth during this lunar cycle, on Thursday at a distance of 227,238 miles.

This is the Skywatch Line for Monday and Tuesday, March 24th and 25th written by Joe Slomka.

The Sun sets at 7:12 PM; night falls at 8:48. Dawn breaks at 5:14 AM and ends with sunrise at 6:50. During Dusk, Jupiter, in Gemini, is the only bright planet visible. It lies due South shortly after sunset. Telescopic observers can see the giant storm known as the Great Red Spot at 10 PM on Monday night, and also at 3:49 AM Wednesday. Binocular and telescopic observers can see the Jovian moon Io appear from behind Jupiter at 7:53 Monday evening. Jupiter sets at 3:10 AM.

Mars rises shortly after nightfall. The Red Planet lies about five degrees above Spica, the brightest star in Virgo. Mars daily grows brighter and larger in our telescopes. Under good conditions, surface features are now telescopically visible. Mars has neighbors in Virgo, the asteroids Ceres and Vesta. Both center on the double star Tau Virginis. Both are challenging objects for the observer. Vesta is closest to the star, only 46 minutes away – a bit larger than a Full Moon. Ceres lies east of Tau, about three degrees away. Both are quite small and appear star-like in telescopes.

Saturn joins Jupiter and Mars, rising in Libra before Midnight. Midnight finds Saturn low in the East, while Mars and Jupiter are ideally placed for observation. Sky watchers can best study Saturn and its amazing rings during the hours before Dawn.

The twenty-four-day-old Moon rises as Jupiter sets. Tuesday finds the Moon in Sagittarius; it moves into Capricornus for Wednesday morning.

Venus rises before Astronomical Dawn. By Civil Dawn, it is moderately high in the East. It appears about half illuminated in a telescope. Venus is best observed in the predawn sky, since it climbs higher and its brilliance can overcome the Sun’s glow. Mercury also rises before the Sun, but is so close to the horizon that observation is difficult.

Gemini is an ancient constellation. The constellation was recognized as “Twins” by many cultures. Castor and Pollux, in Greek legends, were the sons of a mortal and Zeus. They crewed the legendary vessel Argo. Ancient sailors prayed to them for a safe voyage. The phrase “By Jiminy” harks back to an ancient oath. The stars are approximately equally bright. In 1803, Herschel discovered Castor to be a binary – two stars orbiting each other. This was the first binary to be discovered. Now astronomers know Castor to be a six member stellar system.

This is Dudley Observatory’s Skywatch Line for Friday, March 21, through Sunday, March 23, written by Alan French.

The Moon was full last Sunday, so a waning gibbous Moon will rise after midnight over the weekend, leaving the early evening sky dark. The Moon rises just over 30 minutes after midnight on Friday, and each of the following two nights will gain another hour of moonless skies. The Moon reaches last quarter on Sunday.

If you live at or can easily find a location with dark skies to the west, free of light pollution, this is an ideal time to look for the elusive zodiacal light, which appears as a faint, rough triangle of light rising up from the western horizon just after complete darkness falls (the last vestiges of twilight are gone by 9:50 pm). During the next week or so, from our latitude, it extends directly upward from the western horizon, making it easier to see. The zodiacal light is sunlight reflected off a cloud of space dust orbiting the Sun along the ecliptic.

Jupiter, appearing high toward the south southeast as darkness falls, continues to dominate the night sky. Jupiter is due south and highest in the sky – ideal for telescopic observers – at 8:42 pm. Even a modest telescope magnifying about 60 times will show two dark bands crossing the face of Jupiter. These are the North and South Equatorial Belts, one to each side of the lighter Equatorial Zone.

On the southern edge of the South Equatorial Belt is the Great Red Spot, a giant storm in Jupiter’s atmosphere. Jupiter rotates on its axis in just less than ten hours, and the key to spotting the Great Red Spot (GRS) through a telescope is looking near when it is transiting (crossing the middle of the planet). It conveniently transits at 8:20 pm on Saturday night.

As the four bright Galilean moons, Io, Ganymede, Europa, and Callisto orbit Jupiter they appear to shuttle back and forth from our vantage point, sometimes passing behind of or in front of the planet. The moons can be difficult to spot when they pass in front of Jupiter, but their shadows, appearing as inky black dots, are easy to spot.

On Sunday night two shadows will be on Jupiter at the same time. The shadow of Io will move onto the planet at 8:16 pm, and Ganymede’s shadow will slide onto the limb of the planet at 10:07 pm. Io’s shadow will move off at 10:33 pm, and Ganymede’s will leave at 1:26 am Monday morning. The shadows are easiest to spot when near the edge of Jupiter, and a view at about 10:15 will show shadows near each limb.

The Dudley Observatory Skywatch Line for Wednesday, March 19th and Thursday, March 20th written by Louis Suarato.

Asteroids are remnants of the formation of our solar system 4.6 billion years ago. Most of these rocky fragments can be found orbiting the Sun between Mars and Jupiter in what is known as the asteroid belt. There are three broad classifications of asteroids. C-type, or chondrite asteroids, are composed of clay and silicate rocks, and are dark in color. S-type, or stony asteroids, consist of silicate materials and nickel-iron. M-type asteroids are metallic, made up of nickel-iron. The composition of an asteroid provides evidence of how far away from the Sun it formed. NASA has sent several spacecraft to fly by, land on, and observe asteroids. NASA also continuously monitors near-Earth asteroids that may be potentially dangerous, now, or in the future. Spaceweather.com provides a chart of “Recent & Upcoming Earth-Asteroid encounters”. Most of these encounters are beyond the distance of our Moon. This Thursday, at approximately 2:06 a.m. EDT, (depending on your location), asteroid 163 Erigone will pass in front of Leo’s brightest star, Regulus, and block out its light for about 14 seconds. The opportunity to view this occultation is only available to those within a narrow band from northeastern Pennsylvania, through southern New York and the Hudson Valley, and western New York and Canada. Fortunately, there are areas nearby to the north and west of Albany and Schenectady within this range. If you are interested in viewing this rare event, look up 163 Erigone and Regulus on the web for locations.

On Wednesday, the Sun sets around 7 p.m. EDT. The 88% illuminated, waning gibbous Moon rises around 10:30 p.m. below Mars and Spica, in the constellation Virgo. Saturn follows at 11:28 p.m. in Libra. Look for Saturn less than a degree above the Moon Thursday night. Jupiter sets in the west at 3:30 a.m. Thursday. Thursday evening, Jupiter’s moon Europa, begins a transit across the planet at 7:27 p.m., and is followed by it shadow at 9:58 pm. Europa’s transit ends at 10:08 pm. Venus rises just before 5 a.m. Thursday in the constellation Capricornus.

The vernal equinox occurs, and Spring begins in the Northern Hemisphere at 12:57 pm EDT on Thursday.

The Albany Area Amateur Astronomers invite you to join them for star parties this Friday and Saturday, March 21st and 22nd at the George Landis Arboretum in Esperance, NY. Directions to the arboretum can be found at http://www.dudleyobservatory.org/AAAA/Directions.html.

This is the Skywatch Line for Monday and Tuesday, March 17th and 18th by Joe Slomka.

The Sun sets at 7:04 PM; night falls at 8:39. Dawn breaks at 5:27 AM and ends with the Sun rising at 7:02.

As the sky darkens, Jupiter, in the southeast, is the brightest object in the sky. Binoculars can be used to observe some of the four Galilean moons; for example, at twenty minutes past Midnight on Wednesday, the moon Europa disappears behind the giant planet. But a telescope is needed to see the Great Red Spot (giant storm on Jupiter) at 9:14 PM Tuesday and 3:01 AM Wednesday.

Uranus also appears during Dusk, but sets by 8:15 PM. Finder charts are available from astronomy magazines, websites and apps.

The nearly “full” Moon rises around twilight’s end and remains up the rest of the night.

Mars rises at 9:17 PM and, Tuesday night, forms a triangle with the Moon and the bright star Spica in Virgo. Mars is worth observing, now that it rapidly approaches opposition with Earth. Most telescopes will show some surface detail. The March issue of Sky and Telescope magazine has an article with accompanying surface maps to help the observer.

Midnight sees Saturn rise in Libra. The Ringed Planet is a favorite of first time viewers. Saturn and Mars are best studied in the hours before dawn.

Venus rises a half-hour before Dawn and glows brightly in Capricornus. Under moderate power in telescopes, it appears about half illuminated. Mercury rises a half-hour before sunrise and appears bright and low on the eastern horizon, well to Venus’ lower left.

In the 16th and 17th centuries, new constellations were devised to celebrate newly discovered star patterns and high technology of the times. One of these constellations is Sextans, the Sextant. Sextans is found between Leo's front paws and the constellation Hydra.

Johannes Hevelius was a Polish astronomer in the port city of Gdansk (also known as Danzig). In 1641, he built a private observatory that included a 150-foot telescope. However, he did most of his work with a six-foot brass sextant. A sextant contains an arc, one-sixth of a circle. It has a moveable arm that measures angles. In 1679, fire destroyed his observatory. He immortalized his loss with an invented constellation, Sextans, and rebuilt his observatory. Sextants still exist. Sailors use a version that includes a small telescope on the swinging arm and mirrors. Along with an accurate clock and astronomical almanac, the navigator locates the position at sea. That skill is being lost to the increasing use of GPS to fix a location with unprecedented accuracy.

This is Dudley Observatory’s Skywatch Line for Friday, March 14, through Sunday, March 16, written by Alan French.

Full Moon occurs at 1:08 pm on Sunday, so a bright Moon dominates this weekend’s night sky. When close to full, moonrise can be a pretty sight. Low in the sky, the Moon often appears red or orange, and an illusion makes it look larger than normal. On Saturday night the nearly Full Moon rises at 6:19 pm, 44 minutes before sunset, and will be rising slightly north of due east. Moonrise on Sunday night, with the Moon just past full, occurs at 7:20 pm, 16 minutes after sunset, and occurs just a bit south of due east.

I received a call early this week about a ring or halo around the Moon. These 22-degree halos are caused by ice crystals in the atmosphere, and are fairly common. There are other, rarer atmospheric phenomena associated with the Moon and Sun, so it is worth keeping an eye on both the moonlit night and daytime sky. If you visit this website, you can learn about these interesting displays.

If you are up early on Sunday morning you can watch the International Space Station (ISS) glide through the stars high in the sky. The ISS will first appear at 5:50 am in the west southwest when it moves out of the Earth’s shadow and becomes visible 31 degrees above the horizon. Look for it to brighten into view about one-third of the way from brilliant Venus to the Moon and a little higher in the sky than Venus. Following its appearance, it will move up past bright Arcturus, in Bootes. It will reach its highest point at 5:51:23 when essentially overhead. It will then move down toward the northeastern horizon and vanish from view just before 5:55.

On Sunday night telescope users have a chance to see the shadows of two moons cross the face of Jupiter. Ganymede’s shadow will move onto the eastern limb of Jupiter at 6:07 pm, and Io’s shadow will follow at 6:21 pm. Unfortunately, the Sun does not set until 7:04, so the sky will still be bright and Jupiter may prove difficult to find. Although you may miss the beginning of the double shadow transit, the late stages and end occur after darkness falls.

As the Sun disappears below the horizon, Jupiter should be bright enough to spot, very high above the southeastern horizon. You have plenty of time to spot bright Jupiter – the shadow of Io does not leave the planet until 8:38 pm. Ganymede’s shadow departs at 9:25 pm.

The shadows of the moons look like inky black dots against the gas giant’s cloud tops. They are often easiest to spot when they are near the limb or edge of the planet.

The Dudley Observatory Skywatch Line for Wednesday, March 12th and Thursday, March 13th written by Louis Suarato.

The 86% illuminated, waxing gibbous Moon rises at 3:23 p.m. DST on Wednesday in the constellation Cancer. As the sky darkens, look above and left of the Moon for M44, the Beehive cluster. Binoculars or a small telescope will help you find the open star cluster M67 a degree below the Moon. M67 is comprised of approximately 80 stars and is 2,700 light years away. Bright Jupiter, at magnitude -1.9, is to the upper right of the Moon, in the constellation Gemini. At 11:10 p.m. Wednesday, Jupiter’s largest moon, Ganymede, will be occulted by the planet. Thursday, the shadow of Jupiter’s moon, Europa, can be seen transiting the planet at 7:22 p.m. until 10:06 p.m. when the transit ends.

Mars rises at 9:41 p.m. in Virgo, alongside its brightest star, Spica. Mars currently shines at magnitude -.63, but will be brighter at month’s end at magnitude -1.2. Saturn rises just around midnight in the constellation Libra. Saturn will be 30 degrees above the southern horizon before dawn on Thursday at 5:30 as Venus is rising. Researchers have recently reported that, unlike Earth, which is protected by a magnetosphere, Venus experiences giant explosions, called hot flow anomalies, caused by the solar wind. Scientists indicate that Venus’ hot flow anomalies can be so huge they could affect the entire planet and possibly draw its ionosphere up and away from the surface.

Thursday morning features a bright, -3.1 magnitude, International Space Station pass over our region. Look to the southwestern horizon at 6:40. The ISS will rise between Mars and Saturn, and continue on past Hercules, Lyra, and Cygnus before fading into the glow of sunrise. The museum of innovation and science (miSci) is offering April Break Hands-on Science Classes, hands-on fun for children in third through eighth grade, 8:30 a.m. to 5:00 p.m. Monday, April 14 through Friday, April 18.

miSci is offering the following class during April Break: · Astro Kids (grades 3 – 5) Take a journey into space and learn all about our solar system! Investigate black holes, comets, and constellations. Learn why the planets move, make a star map, and fit a solar system in your pocket. Registration is open and space is limited.

This is the Skywatch Line for Monday and Tuesday, March 10th and 11th by Joe Slomka.

Now that Daylight Savings Time is in effect, the Sun sets at 6:56 PM; night falls at 8:30. Dawn breaks at 5:40 AM and ends with the Sun rising at 7:14.

The ten-day-old Moon rose this afternoon, and brightens the sky for most of the night, dimming all but the brightest planets and objects. Jupiter is one of the few that withstand the Moon’s glare. On both nights, the Moon stands to the left of Jupiter in Gemini.

Jupiter is highest at about 8:26 PM, and sets about 4 AM. At about 8 PM Tuesday, telescope observers can witness the moon Callisto’s shadow march across Jupiter’s cloud tops. At 9:49, they can also see Europa, another Jovian moon, disappear behind the giant plant, and then reappear at 3:01 AM, Wednesday morning.

Uranus, in Pisces, is quite low, and a challenge for the observer. It sets about 8:40.

Mars, in Virgo, rises before 10 PM, and, by Midnight, is high enough for observation. Mars grows brighter and larger in our telescopes; under good observing conditions and high power, surface features should be visible. It is best observed about 3:25 AM.

Saturn rises in Libra shortly after Midnight and is best observed around 5 AM. Almost any telescope reveals its beautiful rings; larger telescopes may even spot some of its moons.

Venus is also up by Dawn and located near the edge of Capricornus. Venus replaces the Moon as the brightest object. In a telescope, Venus is about 43 percent illuminated.

Mercury rises eighteen degrees to Venus’ lower left. It is quite low and not as bright, about zero magnitude. In a telescope it is about half illuminated.

March contains two unusual events that are visible to the Capital District. Most people know that eclipses are occasions when one heavenly body hides another, for example the Moon blocking the Sun. Occultations are occurrences when a smaller body is hidden by another; for example, Europa’s disappearance behind Jupiter. Just after Midnight on Tuesday, the Moon will occult the star Lambda Geminorum, also called Alkibash. At thirteen minutes after Midnight, the edge of the Moon begins to cover the star; it reappears at about 1:24 AM. Lambda is moderately bright, at 3.5 magnitude. It is visible to the naked eye; but binoculars are recommended. All of the Capital District can witness this episode.

The second occultation takes place March 20 and is visible to portions of the Capital District. An asteroid will briefly hide the bright star Regulus.

This is Dudley Observatory’s Skywatch Line for Friday, March 7, through Sunday, March 9, written by Alan French.

The Moon reaches first quarter early on Saturday, making this an ideal weekend to do a little lunar observing. Even binoculars will show the larger craters and mountains, and the view through even a modest telescope or spotting scope is impressive. The most detail will be visible along the terminator, the line dividing the sunlit part of the Moon from the part still in darkness. Between New and Full the terminator is the line of sunrise marching steadily across the visible Moon’s face. Look for points and lines of light just over into darkness, where mountain tops and crater walls are just catching the first light of the rising Sun. It’s fun to watch sunrise gradually reveal a crater and illuminate its floor.

Mars now rises at 9:00 pm and is highest and due south just after 2:30 am. In our faster, inner orbit, the Earth is slowly catching up with Mars. We will pass Mars on April 8, when Mars will be at opposition (opposite our Sun in the sky).

Mars can be a difficult target for a telescope. Details are best studied when it appears at least 10 arc-seconds in diameter. Right now it is 12.5 arc-seconds across. At opposition it will be 15 arc-seconds. While Mars is now large enough for a careful observer to spot details, it is only 39 degrees above the horizon. Planets generally show more detail when high above the horizon, and their light passes through less image distorting atmosphere. Around opposition Mars will still be only 42 degrees above the horizon.

Jupiter is now an excellent telescopic target, high in the south by 7:00 pm. On Friday night the Moon Io, followed by its shadow, will cross in front of Jupiter. Io will move in front of the planet at 7:46 pm, followed by Io’s shadow at 8:57 pm. The moon itself can be hard to see against the planet’s cloud tops, but the shadow appears as an inky, black dot, and is visible in even a modest astronomical or spotting scope.

If you don’t have a telescope, but do have binoculars, look closely at Jupiter. You’ll see two stars just to the left or east of the planet, and one to the right or west. The stars to the left will be a bit lower than Jupiter – the one to the right a bit higher. These are the remaining three bright Jovian moons, with Ganymede and Callisto on the left and Europa on the right. The remaining 63 moons are beyond the reach of amateur telescopes.

Io will move out from in front of Jupiter at 10:02 pm, and the shadow will exit at 11:13 pm.

Daylight Saving Time starts this weekend, so set your clocks ahead or “spring ahead” one hour before going to bed on Saturday night. We won’t go back to Standard Time until the first weekend in November. Neither Arizona nor Hawaii observe Daylight Saving Time.

The Dudley Observatory Skywatch Line for Wednesday, March 5th and Thursday, March 6th written by Louis Suarato

The phrase “March comes in like a lion…” is usually used in connection with weather, but it can also refer to the night sky, as the constellation Leo “The Lion” makes its appearance above the eastern horizon after sunset in early March. This prominent constellation is easy to make out using the curvature of the stars that form an asterism, known as “The Sickle”, to shape the Lion’s neck and head. Leo’s brightest star, Regulus, lies along the ecliptic, and is often in the same field of view of the Moon and planets. Shining at a magnitude of 1.35, Regulus is the fifteenth brightest star in our skies. Regulus is only 79 light years from Earth and is comprised of four stars. Leo also contains many bright galaxies, including the LeoTriplet, consisting of Messier objects M65, M66 and New General Catalog object, NGC 3628. This group of galaxies is about 35 million light years away. The Leo Triplet can be found by finding the faint star to the lower left of Regulus, known as Chertan, and looking 2 degrees east.

On Wednesday, the 27% illuminated, waxing crescent Moon sets around 11 pm. In the east, Mars will be rising to the left of the star Spica in the constellation Virgo. At 11 p.m., Jupiter will be approximately 40 degrees above the western horizon. Jupiter’s largest moon, and the largest in our solar system, Ganymede, will be occulted by the planet at 9:36 p.m., and is eclipsed at 11:08 p.m. EST. Jupiter completes its retrograde loop at 5 a.m. on Thursday. Saturn rises a few minutes before midnight in the constellation Libra. Saturn’s largest moon, Titan, will be just below the ringed planet. Venus will be hard to miss as it rises at 4:40 in the morning, followed by Mercury an hour later.

Dudley Observatory Octagonal Barn and Albany Area Amateur Astronomer’s Star Parties return in March! The Star Parties at the Landis Arboretum will be held on the nights of March 21st & 22nd at 8:30. The Octagonal Barn Star Party will be held on the nights of March 28th and 29th at 7 pm. Observatory staff and volunteers will be hosting a Messier Marathon! A Messier marathon is an attempt, usually organized by amateur astronomers, to find as many Messier objects as possible during one night. The Messier catalogue was compiled by French astronomer Charles Messier during the late 18th century and consists of 110 relatively bright deep sky objects (galaxies, nebulae, and star clusters). At low northern latitudes, it is possible to observe all Messier objects in one night during a window of a few weeks from mid-March to early April. In that period the dark nights around the time of the new moon are best for a Messier Marathon. We hope to see you there!

This is the Skywatch Line for Monday and Tuesday, March 3rd and 4th written by Joe Slomka.

The Sun sets at 5:47 PM; night falls at 7:21. Dawn breaks at 4:52 AM and ends with the Sun rising at 6:26.

As Monday night darkens, the observer sees a nine percent illuminated Moon in Pisces; Tuesday finds the Moon fatter and in Aries. The Moon sets before 10 PM. Nightfall reveals Jupiter in Gemini, near Castor’s waist.

Tuesday night, at 11:23, telescopic and binocular observers can witness Europa reappearing from being eclipsed by the giant planet. At 26 minutes past Midnight Wednesday, the Great Red Spot, a giant storm, can be seen in telescopes.

Mars rises after 9 PM, and appears near Spica, the brightest star in Virgo. The Red Planet steadily grows brighter and larger in our telescopes, since Mars is becoming closer to Earth. Mars is accompanied by two minor planets, also called asteroids, Ceres and Vesta. Both share Virgo with Mars. Observing guides are available from magazines, websites and apps. Jupiter sets at 3:30 AM.

Pallas, the second asteroid discovered, lies close to Alphard, the brightest star in the constellation Hydra. Again various astronomical media provide observing guides.

Saturn rises in Libra, before Midnight. Like Mars, it begins a retrograde motion, moving westward. This travel continues until July.

Mars, Ceres, Vesta, Pallas and Saturn are best observed in the hours before Dawn. The planets present ever-changing views of their surface and moons, while asteroids present challenges to beginning observers, since they look star-like and require repeated observation.

Venus rises after 4 AM in Sagittarius and is best observed in the hour before sunrise. Mercury also rises before the Sun and lies low on the eastern horizon. Venus is brighter, while Mercury appears almost as thick a crescent as Venus.

By 10 PM, a bright orange star glows between Mars and the North Pole. This is Arcturus, the brightest star of the constellation Bootes. It is variously translated as "Herdsman" or "Bear Driver." Arcturus is the closest giant star to Earth. Its diameter is 26 times larger than the Sun, but is only four times heavier. Arcturus is an older, bloated, cool star that has probably stopped fusing hydrogen and is consuming helium instead. Arcturus is famous for a few reasons. Proper motion is a star's actual movement through space. Sir Edmond Halley, of comet fame, discovered the star's proper motion in 1718. The 1933 Chicago World's Fair used the light from Arcturus to officially open the event. At that time Arcturus was estimated to be 40 light-years distant, the time of the 1893 Chicago World's Fair. We now know Arcturus is slightly closer, about 37 light-years away.

The Dudley Observatory Skywatch Line for Wednesday, February 26th and Thursday, February 27th written by Louis Suarato.

The 9% illuminated, waning crescent Moon sets at 2:49 p.m. EST on Wednesday, and will rise as a 5% illuminated crescent at 5:06 a.m. Thursday morning. The Moon reaches perigee, its closest distance to Earth during this lunar cycle, on Thursday at 2:51 p.m. EST, when it will be 223,967 miles away.

The rising Moon will be joined by Venus to its upper right in the constellation Sagittarius, along with Saturn above the southern horizon in Libra, and Mars above the southwestern horizon in Virgo. Saturn’s rings are tilted at 22.5 degrees, the widest they will be open until October. Mercury will be a challenge to see about 5 degrees below the Moon and in the brightening light of dawn. You can complete your tour of the planets visible to the naked eye by finding Jupiter high above the southeastern horizon, in the constellation Gemini, after sunset Thursday evening. A telescopic view of Jupiter will reveal its moon, Ganymede, emerging from behind the planet at 5:55 p.m. Wednesday. At 7:08 p.m., Ganymede disappears into Jupiter’s shadow and reappears at 10:22 p.m. when the eclipse ends.

The south to southeastern area of the sky is filled with bright stars joining Jupiter. To Jupiter’s left are Castor and Pollux, Gemini’s brightest stars. Above Jupiter, in the constellation Auriga, is its brightest star, Capella, and to its right, Antares, the brightest star in Taurus. To Jupiter’s right are Betelgeuse and Rigel, the brightest stars of Orion. Below Jupiter is Procyon, the brightest star in Canis Minor. Below Orion and right of Procyon is Sirius, the brightest star in Canis Major and brightest star in our sky.

A binocular or small telescope target located between Procyon and Betelgeuse is the Rosette Nebula, also known as Caldwell 49. A dark sky sight is preferable to see this nebula. There is also a star cluster, NGC 2244, that can be seen within the nebula. This star cluster was formed by the nebula’s matter. The Rosette Nebula is approximately 5,000 light years away and is part of a larger cloud that contains enough gas and dust to form the equivalent of 10,000 Sun-like stars.

The Five Rivers Environmental Education Center’s Winter Astronomy Program has been rescheduled for the night of Friday, February 28th at 7:30. Center staff will provide a naked-eye overview of the winter sky (binoculars optional), while members of the Albany Area Amateur Astronomers train telescopes on fascinating deep-sky objects for you to view. The program is free, but space is limited. Please call Five Rivers at 518-475-0291 to register by Wednesday, February 26. In the event of cloud cover, this program may be postponed.

This is the Skywatch Line for Monday and Tuesday, February 24th and 25th written by Joe Slomka.

The Sun sets at 5:38 PM; night falls at 7:12. Dawn breaks at 5:03 AM and ends with sunrise at 6:37.

At sunset, only Jupiter is readily visible. Jupiter is best observed about 8:20 PM. At that time, binocular and telescopic observers can see all four Galilean moons, Io to one side, Ganymede, Callisto and Europa on the other.

Nightfall finds Uranus low in the western sky. The giant, but difficult, planet is preparing to set in an hour. Finder charts are available in astronomy magazines, websites, and apps.

Mars rises before 10 PM in Virgo. The Red Planet shines a bit East of the bright star Spica. Accompanying Mars, are two minor planets, also called asteroids, Ceres and Vesta, which also inhabit Virgo, about eight degrees from Mars. Finder charts are available in various astronomical media. Mars lies due South at 3:20 AM, when it is best observed.

Dawn begins with Jupiter set, and Mars high in the South. Saturn joins the scene before Midnight, but is best viewed just before Dawn.

The Moon and Venus share Sagittarius. Tuesday’s dawn skies show the 25-day-old Moon to Venus’ right; Wednesday, the Moon glows to Venus’ lower left. A telescope provides a comparison of Venus and the Moon. Both are lit by the Sun. Venus is bright because its clouds efficiently reflect sunlight. Our Moon is actually very dark, roughly the color of highway pavement; it’s bright because it’s bigger and closer. Both planets exhibit phases. Venus is about one third illuminated, while the Moon is twenty percent lit on Tuesday.

Friday is February 28th . When most months have 30 or 31 days, why does February have 28? The old Roman calendar was a lunar calendar of ten months containing 304 days. There was no system for inserting "leap months," resulting in chaos. While Julius Caesar was in Egypt, he met Sosigenes, a prominent mathematician, who suggested reforms to the Roman calendar. Caesar adopted those reforms that resulted in the current calendar of twelve months containing 365 days and leap years. What is less well known is that he shifted a day from February to the newly named month of July (after himself). Augustus, his successor, also borrowed a day from February, so that August (his month) would be equally as long as July.

This is Dudley Observatory’s Skywatch Line for Friday, February 21st, through Sunday, February 23, written by Alan French.

The Moon reaches last quarter Saturday afternoon, so the lunar orb will rise after midnight and the weekend evening skies will be dark.

We have three chances to see the International Space Station (ISS) in the early evening sky this weekend. The times, given in hours, minutes, and seconds, are for Schenectady, but should be close enough for anyone in the Capital District and surrounding region. Two of the passes will move into the Earth’s shadow and fade from view before reaching the horizon.

On Friday night the ISS will appear at 6:55:58 pm coming up from the northwestern horizon, will be highest at 6:59:16 when 57 degrees above the north northeastern horizon, and move into the Earth’s shadow at 7:00:04 when 42 degrees above the eastern horizon. Its path will take it above Polaris, the North Star, and it will move into the Earth’s shadow as it approaches the head of Leo, the Lion.

Saturday’s pass will begin at 6:07:05 pm, with the ISS again moving up from the northwestern horizon. It will be highest at 6:10:14 when 38 degrees above the north northeastern horizon, and will vanish below the eastern horizon just before 6:13. Its path will take it through the Little Dipper’s handle and past the front of the Big Dipper’s bowl.

The ISS will first appear at 6:54:43 on Sunday night, rising up from the west northwestern horizon. The station will be highest at 6:58 when 57 degrees above the southwestern horizon, and will move into the Earth’s shadow and fade from sight at 6:59:52 when 22 degrees above the southeastern horizon. The path will take it along the Great Square of Pegasus, past bright Aldebaran, in Taurus, and right along Orion’s belt. It will move into the Earth’s shadow just after passing brilliant Sirius, the Dog Star.

Saturn now rises just after midnight and will be found close to the half illuminated Moon during the morning hours on Saturday. People in Madagascar, most of Australia, and New Zealand will see the Moon pass in front of or occult Saturn.

The Dudley Observatory Skywatch Line for Wednesday, February 19th and Thursday, February 20th written by Louis Suarato.

“Accordingly, since nothing prevents the earth from moving, I suggest that we should now consider also whether several motions suit it, so that it can be regarded as one of the planets. For, it is not the center of all the revolutions.” – Nicolaus Copernicus, born February 19, 1473

When almost everyone during his lifetime believed that Earth was the center of the Universe, Nicolaus Copernicus proposed that planets revolve around the Sun. Copernicus’ heliocentric model wasn’t exactly correct, but was used by future astronomers to form an accurate model of our solar system.

After sunset on Wednesday, the constellation Orion will be high above the southern horizon. Orion is one of the largest constellations in the sky, covering approximately 600 square degrees. Orion also contains more bright stars than any other constellation, and is the only constellation with two first magnitude stars. Betelgeuse, or Alpha Orionis, is a red supergiant star, residing at the “shoulder’ of Orion. Rigel, or Beta Orionis, is a blue-white star at the foot of “The Hunter”. Below and to the left of Orion’s belt are the stars that comprise the Hunter’s sword. The center star will appear to have a haze surrounding it. This is the Great Orion Nebula or M42. M42 can be seen with the naked eye under the right conditions, but is more evident through binoculars or a telescope. A telescopic view of the Orion Nebula will reveal a star cluster at its center known as the Trapezium. These stars are early in their early stellar life. A line from Orion’s belt westward, leads you to Aldebaran in Taurus and onto the Pleiades star cluster. Follow Orion’s belt eastward to Sirius, the brightest star in our sky.

The 76% illuminated, waning gibbous Moon rises at 10:30 p.m. EST in the constellation Virgo. The reddish “star” 5 degrees above the Moon is the planet Mars. During February, Mars’ brightness will increase from a magnitude of +0.2 to -0.5 as it approaches Earth. NASA’s Mars Curiosity rover is continuing its mission to provide data on the planet’s geology, but recently looked up to transmit of view of Earth from the Martian surface. Jupiter is high above the southwestern horizon in the constellation Gemini as the Moon rises. Jupiter’s moon, Io, is occulted by the planet beginning at 6:58 p.m., and emerges at 10:15 p.m. Wednesday. Saturn rises a half hour after midnight in the constellation Libra. Look for a very bright Venus around 5 a.m. Thursday.

The Five Rivers Environmental Education Center’s Winter Astronomy Program has been rescheduled for the night of Friday, February 28th at 7:30. Center staff will provide a naked-eye overview of the winter sky (binoculars optional), while members of the Albany Area Amateur Astronomers train telescopes on fascinating deep-sky objects for you to view. The program is free, but space is limited. Please call Five Rivers at 518-475-0291 to register by Wednesday, February 26. In the event of cloud cover, this program may be postponed.

This is the Skywatch Line for Monday and Tuesday, February 17th and 18th written by Joe Slomka.

The Sun sets at 5:29 PM; night falls at 7:04. Dawn begins at 5:13 AM, ending with sunrise at 6:48.

After sunset, only Jupiter is visible. It rose in the afternoon, and by nightfall is high in the southeast, between Gemini’s legs. Binocular or telescope users can see all four Galilean moons at Monday’s twilight’s end. Jupiter sets before Dawn.

Uranus occupies Pisces, but sets by 8:51 PM. Finder charts are available from magazines, websites and apps.

The eighteen-day-old Moon rose at 8:27 PM in Virgo. It appears nearly “full,” and remains up the rest of the night. Midnight Tuesday finds it moderately high in eastern skies, near the bright star Porrima. Wednesday’s midnight has the Moon five degrees from Spica, the constellation’s brightest star, and nine degrees West of Mars, also in Virgo.

Besides the rovers Opportunity and Curiosity, the Mars Reconnaissance Orbiter is an artificial Martian satellite. It continually monitors the Red planet for changes. NASA recently released a photo by the orbiter’s HiRISE camera. It shows a new crater on Mars. Some time between July 2010 and May 2012, a space rock crashed onto the Martian surface, created a 100 foot crater and threw debris over nine miles. Space rocks constantly rain down on Mars, but this is the most spectacular one in a while.

Saturn rises after Midnight in Libra. It is ideally observed in the hours before Dawn and lies due South. Saturn is still at Quadrature - ninety degrees from the Sun. The giant planet’s shadow falls on the ring system, a beautiful telescopic sight.

Venus blazes low in the eastern Dawn sky. Venus is officially located in Sagittarius, the arrow-shooting Centaur. However, most people see Sagittarius as a teapot. If that is how you see Sagittarius, Venus lies in the “teaspoon,” an informal asterism accessory to any teapot.

While the new Mars crater went unnoticed for nearly two years, one year ago the past weekend, an asteroid made its presence very obvious. The asteroid exploded over the Siberian town of Chelyabinsk, damaging buildings and injuring over a thousand people. The asteroid’s arrival and disintegration was well documented by Russian dash videos. This coming Thursday, weather permitting, the Albany Area Amateur Astronomers will hold their monthly meeting. The main feature will be a video about the Chelyabinsk meteor and its aftermath. The meeting is held at MiSci at 7:30 PM.

All club events are free and the public is welcome.

This is Dudley Observatory’s Skywatch Line for Friday, February 14, through Sunday, February 16, written by Alan French.

The Moon is full early Friday evening, so the weekend’s night sky will be dominated by bright moonlight. The full Moon of February is known as the Snow Moon or Full Hunger Moon. To Native Americans, it was the time of the most snow, and also often a time of hunger.

On these cold moonlit nights it might be nice to think of some astronomy activities in the year ahead. We are fortunate to live near one of the largest astronomy expositions in the country, and near two fine astronomy conventions. While they attract many experienced amateurs, they are also a lot of fun if you are new to the hobby.

The Northeast Astronomy Forum (NEAF) is held in the field house at Rockland Community College, in Suffern, NY. This year’s event is on Saturday, April 12, and Sunday, April 13, and is their 23rd exposition. The show features more than 100 vendors and exhibiters, high caliber speakers, programs for beginners, and a solar star party. During the solar star party you can get safe views of the Sun through some of the finest solar telescopes being made today. You can find out more at the NEAF website.

This year will mark the 79th Stellafane convention, a gathering of amateur telescope makers and astronomers hosted by the Springfield Telescope Makers and held on Breezy Hill, outside Springfield, Vermont. The dates are Thursday, July 24, through Sunday, July 27. Amateur telescope makers from across the country bring telescopes to display and enter in a competition for awards. Weather permitting, there is observing every night, and a huge variety of telescopes, both commercial and homemade, to view through. (Commercial exhibits, however, are not allowed.) You can visit the Springfield club's website for full details.

If you are just testing the waters of amateur astronomy, it’s hard to beat the small and friendly Connecticut River Valley Astronomers Conjunction, held at the Northfield Mountain Recreation and Environmental Center just south of Northfield, Massachusetts. Their 32nd gathering will be held on Friday, August 22, and Saturday, August 23. It features speakers, a catered dinner, and observing on both nights. Visit their web site for specifics.

Perhaps one would be a nice fit on your calendar.

The Dudley Observatory Skywatch Line for Wednesday, February 12th and Thursday, February 13th written by Louis Suarato.

The Moon reaches apogee on Wednesday, 252,421 miles, its farthest distance from Earth during this lunar cycle. The 96% illuminated, waxing gibbous Moon rises at 3:34 p.m. on Wednesday. As the sky darkens, the star Procyon, in the constellation Canis Minor, will appear to the right of the Moon. At a distance of 11.46 light years, Procyon is one of the closest stars to our Sun and is the eighth brightest star in our sky. Procyon, meaning “preceding the dog”, because it rises before “the Dog Star” Sirius, is a binary star with a companion star about 14.9 astronomical units away from its much brighter main star, Procyon A. The two stars circle each other once every 41 years.

Jupiter can be found above the Moon and Procyon in the constellation Gemini. Jupiter’s moon, Io, begins to transit the planet at 7:50 p.m., followed by its shadow at 8:42 p.m. on Wednesday. Mars rises at 10:28 p.m. alongside the star Spica. Approximately 8 degrees to the left of Mars, look for the two of the brightest and largest asteroids, Vesta and Ceres. The two asteroids are now only less than 4 degrees apart. Vesta shines at magnitude 6.26, while Ceres is at magnitude 5.85. After leaving Vesta’s orbit on September 5, 2012, NASA’s Dawn spacecraft headed for Ceres. Dawn’s mission is to explore the two asteroids, or protoplanets, as two of the first bodies that formed in the solar system. Recently, the Herschel Telescope detected a water atmosphere surrounding Ceres. Dawn is scheduled to arrive at Ceres in April of 2015.

Saturn rises 45 minutes past midnight in the constellation Libra. NASA recently released a photo, taken last November by the Cassini spacecraft, of Saturn’s hexagonal shaped polar vortex. The hexagon, created by 200 mph winds, is about 20,000 miles across. Venus rises at 4:29 a.m. Thursday below the constellation Scutum and above Sagittarius. Venus will reach its maximum brightness, at magnitude -4.9, on February 15th.

This is the Skywatch Line for Monday and Tuesday, February 10th and 11th written by Joe Slomka.

The Sun sets at 5:20 PM; night falls at 6:56. Dawn breaks at 5:22 AM, ending with sunrise at 6:58.

The eleven-day-old Moon rose this afternoon and is stationed six degrees away from bright Jupiter. Both beacons share Gemini and blaze in the southeastern sky. Tuesday’s Moon appears further from Jupiter and to its lower left. In the southwest, Mercury is low. At second magnitude, it should be visible to the binocular user, but its altitude makes Mercury tonight’s challenge object. Mercury sets at 6:16 PM.

Twilight’s end places Uranus in Pisces. This distant planet requires detailed finder charts from astronomy magazines, websites or apps. Uranus sets at 9:23 PM.

Nightfall is prime observing time for Jupiter. Its Great Red Spot, a giant storm, is telescopically visible Tuesday at 2:13 AM and 10:04 PM. The moon Io begins to cross Jupiter’s face at 1:24 AM Tuesday, followed by its shadow; both Io and its shadow finish their travels by 4:29 AM.

Midnight presents Mars and three asteroids. Mars rises at 10:30 in Virgo, about four degrees from the bright star Spica. Earth is approaching Mars, so it appears brighter and larger in our telescopes. The Red Planet’s northern hemisphere will experience summer on February 15th. Observers should begin to see details on the planet, and note shrinkage of the north polar icecaps.

Asteroid 2Pallas is visible to binocular and telescope users. This minor planet is in the constellation Hydra. The Dwarf Planet Ceres and asteroid Vesta share Virgo with Mars. Pallas and Vesta are seventh magnitude, while Ceres is eighth magnitude. Finder charts are available in the usual magazines and digital resources.

Pallas was the second asteroid to be discovered. In 1802, Heinrich Olbers discovered it while searching for Ceres, the first asteroid. Pallas is about 338 miles in diameter. It circles the Sun in a highly inclined orbit. Its surface is made of silicate materials, and classified as carbonaceous chondrite - similar to many meteorites. Its shape and orbit suggest that it was a proto-planet that never developed into a full world.

Saturn rises after Midnight and is best observed in the hours before Dawn. Located in Libra, Saturn is at Quadrature on Tuesday, which means it is ninety degrees from the Sun. Telescopic observers can see Saturn’s shadow on the glorious rings.

Venus rises before Dawn, and blazes low in the southeast. In a telescope, Venus’ crescent thickens while the planet shrinks as it pulls away from Earth.

This is Dudley Observatory’s Skywatch Line for Friday, February 7, through Sunday, February 9, written by Alan French.

We’ve been writing about the conspicuous constellations and bright stars of winter. This weekend we’ll take a closer look at two of winter’s luminaries.

The brightest star in our nighttime sky, Sirius, the Dog Star, is one of our closest stellar neighbors, lying at a distance of just over 8.5 light years. (So the light you see tonight traveled for a little more than 8.5 years before entering your eye.) Its brightness is due mostly to its close distance, although it is inherently 23 time as bright as our Sun.

Although the stars appear fixed, they do move through space and their positions gradually change. With the nearest stars, this change of position is more obvious. In 1718, Edmond Halley, comparing the position of Sirius recorded by Ptolemy with its position in his time, found that Sirius had shifted the apparent diameter of the Moon in 1800 years.

Sirius is a double star, and its companion is appropriately called “The Pup.” It was discovered by the famed American telescope maker Alvin Clark while testing an 18” telescope he had made for Dearborn Observatory. “The Pup,” or Sirius B as it is more formerly known, can be seen in much smaller telescopes, and is a favorite target for amateur astronomers. Due to the extreme brightness of Sirius, shining more than 9000 time more brightly than Sirius B, it is a challenging object, requiring high quality optics and very steady skies. It is far easier to spot at lower latitudes, when Sirius is higher in the sky and an observer is looking through less of our turbulent atmosphere.

In many ways, Procyon, the brightest star in Canis Minor, the Little Dog, is similar to Sirius. It is also bright because it a closer neighbor, lying 11.4 light years away. It also sports a white dwarf companion, Procyon B, with an interesting history. The existence of the companion was first deduced from irregularities in the proper motion of Procyon. As Procyon moves among the stars its motion is not quite in a straight line – it wobbles a little. Friederich Bessel first predicted the existence of a companion in 1844, and its orbit was calculated in 1862 by Arthur Auwers. In 1896 it was finally confirmed visually by John Martin Schaeberle. He was using the 36-inch refractor at Lick Observatory, then the largest telescope in the world. (In the following year the 40-inch refractor at Yerkes Observatory took over the title.)

Procyon B is much harder to see than Sirius B for two reasons. It is closer to Procyon, and the primary star outshines it by a factor of almost 15,000.

The Dudley Observatory Skywatch Line for Wednesday, February 5th and Thursday, February 6th written by Louis Suarato.

On February 5, 1962, five naked eye planets (Mercury, Venus, Mars, Jupiter, and Saturn) along with the Sun and Moon were in conjunction within a 16 degree circle. In some parts of the world, this conjunction coincided with a solar eclipse, where the planets could be seen for a short period of time as the Moon blocked the Sun. The next time five naked-eye visible planets will cluster within a 25 degree circle or less will be September 8, 2040. Look low over the west-southwestern horizon after sunset on Wednesday for Mercury. As Mercury is setting, Jupiter will be approximately 40 degrees above the eastern horizon. At 8:19 p.m. EST, Jupiter’s moon, Io, begins its transit across the planet followed by its shadow about one hour later. At 9:12 p.m. EST, Jupiter’s moon, Callisto, will begin its transit across the planet a few minutes after Io’s shadow has completed its transit. Mars rises at 10:48 p.m. in the constellation Virgo. Mars will be 4 degrees east of Virgo’s brightest star, Spica. Saturn rises in Libra at 1:13 a.m. Thursday. That bright “star” you’ve been noticing on the eastern horizon before dawn is the planet Venus, now shining at a magnitude of -2.97. A telescopic view of Venus will reveal its waxing crescent disk increasing from 13% to 38% illuminated during the month of February. The First Quarter Moon rises at 10:49 a.m. on Thursday. After sunset, the Moon will be high above the southern horizon. To the left and above the Moon is the Pleiades star cluster in the constellation Taurus. The brightest star in Taurus is Aldebaran. Aldebaran is Arabic for “follower”, because it follows the Pleiades. Aldebaran is an orange giant star located 65 light years from Earth and the ninth brightest star in our sky. The diameter of Aldebaran is 44.2 times that of our Sun. Another method of finding Aldebaran is to follow the stars in Orion’s belt from left to right. The next bright star is Aldebaran. Aldebaran appears to be part of the Hyades star cluster, but is twice as far away as the stars with the cluster. On February 8th, Aldebaran will be just 2.3 degress south of the waxing gibbous Moon.

This is the Skywatch Line for Monday and Tuesday, February 3rd and 4th written by Joe Slomka.

The Sun sets at 5:11 PM; night falls at 6:48. Dawn breaks at 5:30 AM and ends with sunrise at 7:06. The Sun now sets ten hours after sunrise, offering hope to Arctic Vortex sufferers.

As the sky darkens, the five-day-old Moon rose this morning and shines high in the South. The Moon inhabits Pisces and sets after 10 PM.

Mercury is moderately low in the southwest. It shines at zero magnitude and appears about one-third illuminated in telescopes. Mercury sets at 6:43. Mercury rapidly fades after February 4th.

Jupiter, still in Gemini, rose in the afternoon and remains up most of the night. Appearing between Gemini’s legs, the planet is retrograding, which means it is heading westward for a while, before resuming the normal eastward path.

Mars rises before 11 PM and remains visible all night. It is best observed before Dawn, when it is about four-and-a-half degrees above the bright star Spica in Virgo. Mars brightens daily and grows larger in our telescopes. Mars’ northern hemisphere is experiencing Summer. Since Mars takes two years to circle the Sun, its seasons last six months. At this time, the Martian polar ice caps begin to melt, posing a challenge for telescopic observers.

Saturn, in Libra, rises after 1 AM and, once Jupiter sets, becomes the largest planet visible. Saturn is at Quadrature, which means it is ninety degrees from the Sun. At that time, the giant planet’s shadow falls on the beautiful rings. The hour before Dawn is an ideal time to see the glorious rings, which are tilted 23 degrees to our point of view.

Venus rises an hour before sunrise. At Dawn, is lies about six degrees high in the southeast. The brightest object in the sky, Venus appears about 16 percent illuminated in our telescopes.

In 1762, Charles Messier discovered his first comet. This is not an unusual event; comets have been observed for millennia - usually by accident. Messier wanted to observe them systematically by scanning the skies. While searching, he kept finding fuzzy things that looked like comets, but never moved. Comets travel across the sky. He listed over a hundred such objects, so he would not be fooled again. These objects (later identified as galaxies and star clusters) form the basic list for beginning astronomers.

This is Dudley Observatory’s Skywatch Line for Friday, January 31, through Sunday, February 2, written by Alan French.

Last week we covered Orion, the Hunter, high toward the south at 9:00 pm. We pointed out the three stars that outline his belt, his sword stars, and the pairs of bright stars marking his shoulders and knees. Learning the sky is easiest if you start with the obvious landmarks, and now you can use distinctive Orion to find other bright stars and constellations in the winter skies.

If you draw a line through the belt stars, starting from the east or lower left, and continue the line across the sky, it passes near a bright, reddish star. This is Aldebaran, the brightest star in Taurus, the Bull. Note that Aldebaran is close to the top of the left side of a slanted “V” of stars, sitting on its side, with the bottom of the “V” to the right, and the right side of it passing above Aldebaran. This “V” outlines the face of the Bull, with Aldebaran forming one eye. The stars in this pattern are actually members of a star cluster called the Hyades. If you extend the sides of the “V” you can see the bull’s horns.

Now imagine a line through the belt stars continuing in the other direction. You’ll soon come to Sirius, the Dog Star, the brightest star in our nighttime sky, and in Canis Major, the Great Dog. Depictions of the Great Dog in old atlases often show Sirius marking the dog’s throat or chest. A triangle of stars below Sirius outlines his hindquarters.

Last weekend we pointed out Jupiter, the brightest “star” above and left of Orion at 9:00 pm. Farther from Orion, in the same direction, is a pair of bright stars, Castor and Pollux, which mark the heads of the twins of the constellation Gemini. The higher star is Castor. Lines of stars extending toward Orion represent the twins. Between but below a line between Pollux and Sirius is bright Procyon, marking Canis Minor, the Little Dog, an otherwise inconspicuous constellation.

Well above Orion is brilliant Capella, the Goat star, and brightest star in Auriga, the Charioteer. The charioteer was also responsible for the king’s livestock, and old atlases often showed Auriga holding young goats, or kids. The triangle of stars to the lower right of Capella is known as “The Kids.” The constellation is formed by a rough pentagram of stars, with Capella at the top.

All the bright stars we have mentioned, plus Rigel in Orion, form a pattern of stars or asterism known as the “Winter Circle.”

The Dudley Observatory Skywatch Line for Wednesday, January 29th and Thursday, January 30th written by Louis Suarato.

On Wednesday, the 3% illuminated, waning crescent Moon crosses the sky ahead of the Sun. If you use caution and block the Sun, you may be able to see the Moon during daylight. If you’re successful, you can use the Moon to see Venus during daylight. Venus will be located approximately 10 degrees, or the width of a clinched fist of a fully extended arm, to the lower right of the crescent Moon. The Moon reaches perigee, its closest distance to the Earth during this lunar cycle, at 4:59 a.m. EST, at a distance of 221,879 miles on Thursday. The New Moon occurs at 4:39 p.m. the same day, when the Moon is between the Earth and Sun. During full and new moon phases, when the Sun, Moon and Earth are aligned, a configuration called syzygy, the gravitational pull on the water facing the Moon is greater and causes higher than normal tides. To compensate for the gravitational pull on the water facing the Moon, the water on the opposite side of the Earth also bulges. These tides are known as spring tides, not because of the season, but because the water “springs” higher than normal. The shorter distance between the Earth and Moon at lunar perigee increases this effect, when gravitational forces of the Moon upon the Earth can increase by as much as 50%.

After sunset, at approximately 5:30 p.m., look about 10 degrees above the west-southwestern horizon for Mercury. Mercury will be at its greatest elongation, or angle between the Sun and the planet, on Friday, at 5 a.m. EST. As the sky darkens, look about 30 degrees above the horizon where Mercury set, for Uranus in the constellation Pisces. Uranus currently shines at magnitude 6.22. The only bright star in the constellation Pisces is Fomalhaut. Formalhaut, Latin for “fish’s mouth”, is the 13th brightest star in our sky. The star is a close neighbor to our Sun, residing 22 light years away. Above the north-northwestern horizon, where the Big Dipper asterism is rising in the constellation Ursa Major, M82 (the Cigar Galaxy), is making news. A bright supernova has been discovered within the galaxy and can be seen with small telescopes. At 12 million light years away, this supernova is one of the closest and brightest since 1993. Above and east of the Big Dipper, is Jupiter in the constellation Gemini. At 6:33 p.m. on Wednesday, Jupiter’s moon Io will complete its transit across the planet followed by its shadow about one half hour later. Jupiter’s moon Europa begins its transit at 1:34 a.m. followed by its shadow at 2:46 a.m. Thursday morning. Mars rises in the constellation Virgo at 11:06 p.m., and Saturn rises at 1:42 a.m. in Libra. Venus will appear very bright above the east-southeast horizon around 6 a.m. in the constellation Scutum.

The Five Rivers Environmental Education Center is hosting a Winter Astronomy Program on Friday, January 31 at 7:30 p.m. Join us for a close look at seasonal constellations and other heavenly bodies. Center staff will provide a naked-eye overview of the winter sky (binoculars optional), while members of the Albany Area Amateur Astronomers train telescopes on fascinating deep-sky objects for you to view. Parent(s) and child(ren) must accompany each other. Dress for outdoor fun. The program is free, but space is limited. Please call Five Rivers at 518-475-0291 to register by Wednesday, January 29. In the event of cloud cover, this program will be postponed.

This is the Skywatch Line for Monday and Tuesday, January 27th and 28th written by Joe Slomka.

The Sun sets at 5:02 PM; night falls at 6:40. Dawn breaks at 5:36 AM, ending with sunrise at 7:14.

After sunset, two bright lights shine at opposite ends of the sky. Mercury lies low in the southwestern sky about a half-hour after sunset. At magnitude of -0.8, it is the brightest object in that sector of the sky, appearing about two-thirds illuminated in a telescope. Mercury sets at 6:31.

Jupiter rose in mid-afternoon, and is moderately high in eastern skies. Nightfall sees bright Jupiter between Gemini’s legs. At twilight’s end, a binocular observer sees three Galilean moons to one side of Jupiter, with Io on the other. At 9:52 PM, Monday, Io begins to cross Jupiter’s face – a telescopic sight; at 10:24, Io’s shadow follows. Seven minutes after Midnight on Tuesday, Io finishes its transit, followed by its shadow 40 minutes later.

Neptune, in Aquarius, sets early now – at 7:14 PM. Uranus, in Pisces, remains visible until 10:16 PM.

Mars joins Jupiter in midnight skies; its red glow lies about five degrees above the bright star, Spica, in Virgo.

Saturn joins Mars and Jupiter in pre-dawn skies. The giant planet glows in Libra. Its rings are ideally placed for telescopic observation – the sensation for any star party.

Venus rises during Dawn, just before Jupiter sets. It appears very low in the East, requiring an unobstructed horizon. It appears about 10 percent illuminated in telescopes and binoculars. The waning Moon is also up during Dawn. Tuesday, it, too, is quite low in Sagittarius; it is only nine percent illuminated and six degrees away from Venus. Wednesday morning, the Moon is even lower and thinner, preparing to become “New” on Thursday.

Riding high in the South about 9:00 PM is the object astronomers call M45, but commonly called the Pleiades. The Pleiades form a mini dipper that is so distinctive that virtually all cultures have named and worshiped it. Many used it as a farming calendar. When the Pleiades rise in the Fall, it is time to harvest; when it sets in the Spring, it is planting time. Ancient Greeks called it the "Seven Sisters", and other societies had similar names, giving rise to the legend of the "Lost Pleiad". One of the stars has apparently dimmed in the past, because most people can see only six stars without optical aid. Most likely, the star known as Pleione was brighter in ancient times and had recently dimmed.

This is Dudley Observatory’s Skywatch Line for Friday, January 24, through Sunday, January 26, written by Alan French.

The Moon is at last quarter early Friday, so a waning crescent Moon rises after midnight this weekend, leaving the evening sky nice and dark. The Sun sets at 5:00 pm and the last traces of evening twilight are gone by 6:40.

The winter sky is filled with bright stars, and many constellation patterns are obvious and easily recognized. By 9 pm the brightest and most familiar constellations of the season are approaching due south, when they are highest.

Orion, the Hunter, is one of the most recognized constellations in the night sky. Its pattern of bright stars is very distinctive, and nicely outlines a hunter standing in the sky. Look first toward the south for a pattern of three equally bright, equally spaced stars in a line, slanting upward to the right. These stars form Orion’s belt.

If you have the right stars, you should also see a line of three stars hanging downward from his belt, a little left of center. These stars outline his sword, and if you look closely you can see the bottom star is fuzzy. It is not a star - it is a cloud of gas and dust, the Great Orion Nebula, a stellar nursery. Under dark skies, its unusual character can easily be seen in binoculars, and it is a marvelous sight though a telescope. With a large telescope, it is one of the few celestial sights bright enough to engage our daytime color vision, and shows green and more subtle reds.

Above the belt two stars mark Orion’s shoulders. To the left, brilliant Betelgeuse marks his right shoulder, and to the right bright Bellatrix marks his left. Below the belt and sword, two more bright stars mark his knees, with the brightest, Rigel, a bluish star, to the right, and Saiph to the left.

After you’ve traced the outline of Orion, note all the bright stars surrounding Orion. The brightest, well to the upper left, is an interloper, the planet Jupiter. Next weekend we’ll cover some of the other bright stars and constellations near the Hunter.

Early risers can see a fine pass of the International Space Station on Saturday morning. From the Capital District and surrounding region it will pass high overhead. The times will be given in hours, minutes, and seconds. If you miss it as it rises into the sky, look for it when it passes overhead.

The ISS will first appear at 6:18:36 am when emerging from the Earth’s shadow and 16 degrees above the west northwestern horizon. Its path will take it up along the bottom of the Big Dipper. It will be overhead just after 6:21, and will then pass through Bootes and Corona Borealis. If you have a good view to the south southeast, watch as it passes bright Venus just before 6:25. Venus will be seven degrees above the horizon.

The Dudley Observatory Skywatch Line for Wednesday, January 22nd and Thursday, January 23rd written by Louis Suarato.

As the Sun sets at approximately 5 p.m. EST on Wednesday, look for Mercury about seven degrees above the west-southwestern horizon. Mercury will reach its greatest elongation on January 31st. In the east, Jupiter, shining at magnitude -2.2, is almost 40 degrees high by 6:30 p.m. in the constellation Gemini. Jupiter’s moon, Europa, will begin to transit the planet at 11:17 p.m. Wednesday night. Europa’s shadow will follow the moon about an hour later. Look ten degrees to Jupiter’s upper right, at the foot of the top Gemini twin, for open cluster M35. M35 is about the size of the full Moon and is 2,800 light years from Earth. A more compact open cluster, NGC 2158, can be seen one degree to the lower right of M35. These two star clusters reside close to the center of the Winter Circle of stars comprised of Castor in Gemini, Capella in Auriga, Aldebaran in Taurus, Rigel in Orion, Sirius in Canis Major, and Procyon in Canis Minor. The Winter Circle is now at its highest around 11 p.m. above the southern horizon.

Approximately 20 degrees above Jupiter and to the lower right of Capella are three more open clusters, M36, M37, and M38. To locate M36, use a star chart to find the star Theta Aurigae. M36 can be found 5 degrees southwest of Theta Aurigae. Several of the brightest stars in this open cluster are lined in rows. M37 is 4 degrees east-southeast of M36. A small telescope will reveal a bright orange star at the center of M37. About two degrees northwest of M36 is M38. M38 is comprised of about 100 stars of magnitude 10 or fainter.

The 61% illuminated, waning gibbous Moon, rises in the constellation Virgo at 11:35 p.m. Wednesday night. Look for Mars about four degrees to the Moon’s upper left. The Moon will also be 1.5 degrees above Virgo’s brightest star, Spica. Saturn rises at 2 a.m. in Libra. Venus rises at 5:43 Thursday morning, providing the opportunity to view four planets in the pre-dawn sky.

This is the Skywatch Line for Monday and Tuesday, January 20th and 21st written by Joe Slomka.

The Sun sets at 4:53 PM; night falls at 6:32. Dawn breaks at 5:40 AM and ends with sunrise at 6:49. Tuesday is exactly one month after the Winter Solstice - the shortest day of the year. We have gained about a half-hour of extra sunlight during that period.

As the Sun sets, Jupiter is the brightest object in the sky. It is high in the Northeast, between Gemini’s legs. While binoculars can see the dance of Jupiter’s four Galilean moons, telescopes capture the moon Io beginning to cross Jupiter’s face at 8:06 Monday night, followed by Io’s moon a half-hour later. At 10:22 PM, Io leaves the planet’s face; its shadow exits about 32 minutes later.

Uranus continues its stay in Pisces; Neptune still lies in Aquarius. Charts are available in astronomy magazines, websites and apps.

A waning Moon rises in Aquarius at 9:33 Monday night and an hour later on Tuesday. Also occupying Aquarius is Mars, now becoming brighter and larger in our binoculars and telescopes. Saturn appears in Libra at 2:12 AM. Saturn grows slightly in our eyepieces, but remains the same brightness.

Venus emerges during Dawn and blazes low in the eastern sky. A telescope shows it about four percent illuminated at a magnitude of -4.3.

As mentioned last week, Sirius B, or “The Pup” was the first discovered White Dwarf star. But what is a “white dwarf? ” White Dwarfs are the dead cores of Sun-like stars. These stars, toward the ends of their lives, shed layers until all that is left are the exposed dead interiors of dying stars. They no longer fuse hydrogen, but shine from leftover heat, are mostly carbon, and slowly cool down. These dead centers have the mass of a Sun-like star, but compressed into Earth size. Some planetary nebulae, like the Ring Nebula in Lyra, have white dwarfs in the center. They are normally not very bright, but shine in ultraviolet or X-Rays. Some white dwarfs are members of binary systems. These dwarfs steal material from their larger companions and become reenergized. The accumulated hydrogen suddenly flashes; the result is a “nova,” which suddenly brightens in the night sky. Some binary white dwarfs exceed the “white dwarf limit,” and blow themselves apart as White Dwarf Supernovae. White Dwarf Supernovae are called Type I supernovae; Type II are giant stars blowing themselves apart. Type I supernovae act as “standard candles,” which enable astronomers to estimate the distance to galaxies. Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, January 17, through Sunday, January 19, written by Alan French.

The Sun now sets at close to 4:50 pm, and the skies are completely dark and free of any twilight glow by 6:30 pm.

The Moon was full late this past Wednesday, so a waning gibbous Moon will dominate much of the night sky. The Moon rises at 6:38 pm on Friday, 7:36 pm Saturday, and 8:34 pm Sunday. It will reach last quarter very early on the 24th, and will not rise until after midnight on the 23rd.

Venus now rises an hour before the Sun and can be spotted low in the morning twilight. The Sun rises at 7:23 am, so look for Venus at about 6:50 am. It will be five-and-a-half degrees above the east southeastern horizon.

Saturn and Mars are also visible in the morning sky. Saturn is approaching due south as twilight begins to encroach on the eastern sky, and is in the constellation Libra, the Scales. Libra is the only one of the twelve Zodiacal constellations named for an inanimate object. The stars of Libra are faint, and Saturn easily outshines them.

Reddish Mars is higher and toward the south southwest. It is in the constellation Virgo, the Virgin, not far above brilliant Spica, the only bright, first magnitude star in this rather inconspicuous constellation.

The X-37B is a classified unmanned, robotic spacecraft launched on December 11, 2012, from the Cape Canaveral Air Force Station. This is the third X-37 to orbit the Earth. It looks a bit like a miniature Space Shuttle, and can glide to a landing. The first two X-37s were successfully returned to Earth, landing at Vandenberg Air Force Base.

You can see the current orbiting X-37B crossing high over our area early Saturday evening. While not as bright as the Space Station, the second magnitude X-37B should be easy to spot, and it’s fun to see a “secret” satellite.

The X-37B will first appear at 6:09:31 pm in the west. It will pass overhead at 6:12:41, and will move into the Earth’s shadow and fade from view at 6:14 pm when 33 degrees above the east southeastern horizon. (If you miss it coming up from the western horizon, look for it high overhead just before 6:13 pm.)

Its path will take it south of Cygnus, the Swan, through Andromeda, past Perseus, and it will move into the Earth’s shadow as it passes Orion.

The Dudley Observatory Skywatch Line for Wednesday, January 15th and Thursday, January 16th written by Louis Suarato.

The Moon rises at 4:44 p.m. EST Wednesday, becoming full at 11:53 p.m. below the constellation Gemini and the planet Jupiter. This Full Moon will be the smallest of 2014 with lunar apogee occurring just two hours earlier. At apogee, the Moon will be 252,607 miles from Earth. The Moon’s diameter at lunar apogee is approximately 12% smaller than the Moon at perigee or about 4 arcseconds shorter. The star to the lower right of the Moon is Procyon, the brightest star in the constellation Canis Major. At magnitude 0.34, Procyon is the eighth brightest in the night sky. Procyon’s brightness is the result of its closeness to our Sun. At a distance of 11.46 light years, Procyon is one of our Sun’s nearest stellar neighbors. Procyon is also a binary star with Procyon A, its white dwarf companion star. Procyon means “before the dog”, which refers to star following Sirius, “the Dog Star” and brightest star in Canis Major and brightest in the night sky. Sirius can be found to the lower right of Procyon. Mars rises in Virgo at 11:37 p.m. followed by Saturn at 2:29 a.m. in the constellation Libra. Saturn will be between reddish Mars above and reddish Antares below. Mercury and Venus are lost in the glow of morning twilight, but will be able to be seen within a week.

This is the Skywatch Line for Monday and Tuesday, January 13th and 14th by Joe Slomka.

The Sun sets at 4:44 PM; night falls at 6:25. Dawn breaks at 5:43 AM and ends with the Sun rising at 7:23.

The thirteen-day-old Moon dominates the sky. It lies low in the East amid the stars of Orion and Taurus. The nearly full Moon remains up almost to sunrise. Tuesday evening has the Moon six degrees away from Jupiter.

Only the bright planet Jupiter withstands the Moon’s glare.

It appears as the brightest object in the constellation Gemini. Jupiter appears to the Moon’s lower left. Telescopic observers, who brave the season’s cold, are rewarded by an evening treat. At 6:23 PM, Monday, Jupiter’s moon Io begins to cross the planet’s face; twelve minutes later, Io’s shadow follows. At 7:38 PM, Io ends its trek across Jupiter, followed by its shadow, thirteen minutes later.

Uranus still occupies Pisces; and, Neptune remains in Aquarius. Astronomy magazines, websites and apps provide observing guides to these dim members of our Solar System.

Mars rises before Midnight and is found midway between Virgo’s brightest stars: Spica and Porrima. The Red planet grows brighter and larger during the first quarter of the year.

Saturn comes up at 2:37 AM in central Libra. A spectacular sight in any telescope, Saturn shows its famous ring system tipped twenty-two degrees, with the northern side facing us.

Venus hugs the eastern horizon 40 minutes before sunrise.

An unobstructed horizon is necessary to observe it as a rather large image – one arc minute in size. At minus 4 magnitude, Venus is the brightest object in the sky, but only about one percent illuminated.

After sunset, the giant constellation Orion appears. Canis Major, the Big Dog, follows at Orion’s heels. Sirius, the Dog Star, its brightest star, is the seventh closest star to our Solar System, at 8.6 light-years. Although stars seem fixed in our sky, they are actually traveling in different directions and different speeds. Sirius is one of these. In sixty thousand years, it will approach to 7.8 light-years and marginally increase in brightness. Sirius has a companion, appropriately nicknamed “The Pup.” Telescope makers, testing a new telescope, accidentally discovered "The Pup" in January 1862. This star closely orbits Sirius every fifty years. Sirius B, as the companion star is formally called, is much smaller and dimmer than the primary. The Pup is currently distancing itself from Sirius and can be seen with high powers in medium to large amateur telescopes, once Sirius' glare is blocked.

Clear Skies.

This is Dudley Observatory’s Skywatch Line for Friday, January 10, through Sunday, January 12, written by Alan French.

The Moon was at first quarter late this past Tuesday, so a waxing gibbous Moon will dominate the weekend’s night sky. The Moon will reach full late this coming Wednesday.

Jupiter continues to grace the evening sky, lying in Gemini low in the east northeast as darkness falls. Jupiter will be high in the south and best placed for telescopic observation between 11:15 pm and 12:15 am. Even a modest spotting or astronomical telescope will easily show the planets four largest and brightest moons. Since people are usually reluctant to stay up until midnight, we’ll give the positions of the moons at 8:00 pm, when Jupiter will be 41 degrees above the eastern horizon. When the moons are well away from the planet, they can even be spotted in steadily held binoculars.

At 8:00 pm on Friday night Ganymede and Europa will be close together to the east of Jupiter, with Europa closest to the planet. Callisto will be well to the west of Jupiter, with Io a little less than halfway between Jupiter and Callisto. On Saturday night, Europa will be east of Jupiter with Io halfway between Jupiter and Europa. Ganymede will be well to the west, while Callisto will be close to the western limb of Jupiter. Sunday night will find Callisto to the east, and Io, Europa, and Ganymede strung out to the west, with Ganymede farthest away. It’s fun to watch the changing positions of the moons from night to night.

If you’re willing to get up early, or happen to be up, there are two fine passes of the International Space Station visible in the morning skies. On Saturday morning this ISS will appear in the west southwest at 6:18 am, will be highest when 67 degrees above the north northwestern horizon just before 6:21, and will vanish in the northeast at 6:24. Its path will bring in up through Leo, the Lion, through the bowl of the Big Dipper, and down just past bright Deneb in the constellation Cygnus, the Swan.

The pass Sunday morning will be quite interesting – the ISS will emerge from the Earth’s shadow and become visible when high above the southern horizon. Look for it to appear at 5:32 am high up in the southeastern sky, 74 degrees above the horizon (almost overhead), and not far from the bright star Arcturus, in the constellation Bootes. After emerging from the Earth’s shadow and brightening, the ISS will glide down to the east northeastern horizon and vanish just after 5:35. Its path will take it though kite-shaped constellation, Bootes, the Keystone of Hercules, and just past bright Vega in Lyra.

The Dudley Observatory Skywatch Line for Wednesday, January 8th and Thursday, January 9th written by Louis Suarato.

“Remember to look up at the stars and not down at your feet. Try to make sense of what you see and wonder about what makes the universe exist. Be curious. And however difficult life may seem, there is always something you can do and succeed at. It matters that you don't just give up.” - Stephen Hawking, born January 8, 1942

On Wednesday, the First Quarter Moon rises at 11:35 a.m. EST. Six major seas, or “maria” can be seen during the first quarter phase. From the northern (top) portion of the Moon (without being inverted by a telescope), you will see Mare Frigoris, Sea of Cold; Mare Serentatis, Sea of Serenity; Mare Tranquillitatis, Sea of Tranquility; Mare Nectaris, Sea of Nectar; Mare Crisium, Sea of Crises; and Mare Foecunditatis, the Sea of Fertility. One of the prominent craters that can be seen during this phase is Aristoteles, located south of Mare Frigoris. Aristoteles is 55 miles wide and 12,000 feet deep. A small telescope will reveal two peaks on the floor of the crater. To the east, or right of Aristoteles, are the craters Hercules and Atlas. To the south is Posidonius on the northeast edge of Mare Serentatis. Posidonius is approximately 60 miles in diameter.

After sunset, a challenge will be to spot Venus less than 5 degrees above the west-southwestern horizon. Venus is a 1% illuminated crescent as it approaches inferior conjunction on January 11th. From January 9th through January 12th, Venus may be seen as both a morning and evening star as it passes 5 degrees above the Sun. Be careful not to look directly at the Sun if attempting to view Venus during these dates. Jupiter, just past opposition, rises at 4:08 p.m. EST, and will be visible throughout the night in Gemini. Jupiter’s moon Europa can be seen crossing the face of the planet from 6:47 to 9:29 p.m. EST, followed by its shadow 10 minutes later. Mars rises a few minutes before midnight in Virgo. Saturn rises around 3 a.m. in Libra. Saturn’s rings are currently tilted relative to Earth at an angle of 22 degrees. That angle will remain until October of this year when they begin to widen until the angle increases to 24.5 degrees by year-end.

This is the Skywatch Line for Monday and Tuesday, January sixth and seventh by Joe Slomka.

The Sun sets at 4:37 PM; night falls at 6:18. Dawn breaks at 5:44 AM and ends with sunrise at 7:25.

As the Sun sets, the six-day-old Moon is high in the South; it becomes First Quarter Moon on Tuesday. Venus glows brightly low in the southwest. With an unobstructed horizon, Venus appears as a very thin crescent three degrees above the horizon. Jupiter, now at opposition, rises at Sunset and sets at Sunrise. It appears as the brightest object in Gemini all night.

Mars rises, in Virgo, before Midnight and remains up until sunrise. Saturn, in Libra, rises at 3 AM and also is visible until Sunrise.

Monday, January 6, is the Christian feast of the Epiphany, otherwise known as “Three Kings Day.” But, who were these “kings?” Most likely they were Magi from the eastern empire of Babylon. The Babylonians were famous for their astronomical skill. By 2000 BC, they identified all five visible planets, the major constellations, the zodiac and the Saros cycle of eclipses. These priest-astrologers were very powerful and respected throughout the known world.

These dedicated sky watchers would certainly have noticed any new object or event in the night sky. While some think that a comet or supernova may have been the “Christmas Star.” The prevailing opinion is that it may have been an astrological event: the most likely being at triple conjunction between Saturn and Jupiter during the year 7 BC. During the course of the year, Jupiter appears to: chase Saturn, catch up with it, pass it, turn around and catch up with and pass Saturn again, and finally catch up with Saturn one more time before sailing eastward past it. This startling series of events took place in Pisces, a significant constellation. While we now know the planets to be worlds like our own Earth, to the ancients stars and planets were messengers from the gods. When two planets, associated with the most powerful gods, keep meeting, the Magi knew something significant was about to happen. These scholars were also familiar with their neighbors. A search of Jewish documents provided the inspiration to set off for that distant land and a possible meeting with a new god-king.

Clear Skies

This is Dudley Observatories Skywatch Line for Friday, January 3, through Sunday, January 5, 2014 by Alan French.

The Moon was new on New Year’s Day, and will reach first quarter very late this coming Tuesday, so a young crescent Moon will grace the early evening sky this weekend. Look for a slender Moon in the southwest at 5:00 pm on Friday. A fatter crescent will be higher and a bit farther south as darkness falls on Saturday, and an even higher and larger crescent will grace Sunday evening’s sky. The Moon sets at 7:45 pm Friday, 8:59 on Saturday, and not until 10:10 pm on Sunday.

Friday is the peak of the annual Quadrantid meteor shower. Alas, we will miss the shower’s brief peak, which occurs during daylight hours for us – at 12:30 pm Friday. A few stragglers might be visible after dark on Friday night.

If you trace the path of a meteor back across the sky you find that all shower members seem to radiate from the same region of the sky. Meteor showers are named after the constellation where this “radiant” is found. The Perseids are named for Perseus, the hero who saved Andromeda, and the Geminids are named for Gemini, the Twins. So where did we get the Quadrantids?

It is named for an obsolete constellation, Quadrans Muralis, the Mural Quadrant. The constellation used to lie among the dim stars between the end of the Big Dipper’s handle and the head of Draco, the Dragon. It didn’t make the cut when the official constellation boundaries were drawn in 1930.

There are 88 constellations. Forty eight constellations were listed by the Greek astronomer Ptolemy in the second century. One of these, Argo Navis, the ship of Argo, was very large, and eighteenth century astronomers divided it into three parts, Carina, the Keel, Puppis, the Poop or stern, and Vela, the sails.

Other constellations were added when explorers traveled south, seeing stars that were invisible to the Greeks. As people began charting the sky, and producing maps of the stars, they added more constellations, using the dimmer stars between the constellations of the Greeks. Some of these survived, like Canes Venatici, the Hunting Dogs, and Vulpecula, the Little Fox. Others, like Felis, the Cat, and Rangifer, the Reindeer, did not.

The Dudley Observatory Skywatch Line for Wednesday, January 1st and Thursday, January 2nd 2014 written by Louis Suarato.

The New Year begins with a New Moon. The New Moon occurs at 6:14 a.m. EST on Wednesday. The Moon will also be at perigee, 221,781 miles from Earth at 3:59 p.m., its closest distance for the month. These two coinciding events will cause higher and lower tides than normal. An extreme example is the on the Bay of Fundy, where the tides will swing from a low tide of just below sea level on Wednesday to a high tide of 45.5 feet above sea level. The last time a New Moon occurred on New Year’s Day was in 1995. There will also be two New Moons this January. The second occurs on January 30th. The nights before and after the New Moon offer great opportunities to view deep sky objects. Good targets for the winter’s sky can be found in the constellation Cassiopeia. Cassiopeia is located high in the northwest after 8 p.m. EST. There are eight open clusters that can be viewed opposite the deepest “V” in the constellation and four more on the other side towards the middle. The brightest open cluster is NGC 129 at magnitude 6.5. NGC 129 can be found between the two top stars (Gamma and Beta Cassiopeiae) of the deeper V shape. Closer to Gamma Cassiopeiae is open star cluster NGC 225. NGC 225 was discovered by Caroline Herschel in 1784 and contains approximately “20 moderately bright to fairly faint stars” according to Sue French in her book “Celestial Sampler”.



The opportunities of viewing crescent Venus are fleeting as the planet continues to appear lower on the southwestern horizon after sunset. On Wednesday, the face of Venus will be just 3.4% illuminated. Thursday evening, after sunset, offers a view of a 3% illuminated, waxing crescent Moon approximately 5 degrees to the upper left of crescent Venus. Jupiter rises in Gemini around 5:30 p.m., shining at magnitude -2.23. Jupiter’s disk is fully illuminated as it reaches opposition this weekend and will be visible the entire night. If you view Jupiter with a telescope before 7 p.m., you will see Europa and its shadow transiting the planet. Sirius, the brightest star in the sky, rises in the southeast around 7:30 p.m. in the constellation Canis Major. The brightness of Sirius is a result of its proximity to our solar system, only 8.8 light years away, the fifth closest of all known stars. You’ll have to wait until after midnight to see Mars, which rises at 12:30 a.m. in the constellation Virgo. On Thursday at 7 p.m. EST, Mars reaches aphelion, its furthest distance from the Sun at 154.9 million miles. Saturn rises in Libra at 4 a.m. Thursday, providing the opportunity to view three planets in the pre-dawn sky.

This is the Skywatch Line for Monday and Tuesday, December 30th and 31st, 2013 by Joe Slomka.

The Sun sets at 4:30PM; night begins at 6:12. Dawn breaks at 5:44 AM and ends with the Sun rising at 7:26.

The darkening sky reveals only one bright planet – Venus. It daily appears lower in the western sky, but also larger and thinner. Venus lies about nine degrees above the horizon and about four percent illuminated. It sets at 6:04 PM.

Nightfall shows Uranus and Neptune in their yearlong spots in Pisces and Aquarius respectively. Neptune is moderately low in the West and sets at 9 PM.

Jupiter, in Gemini, is retrograding the month, which means that it moves westward for a while, before resuming eastward motion. Earlier this month, it was close to Pollux’s waist; now, it roams between the Twin’s legs. By 9 PM, Jupiter is high enough for observation of its Great Red Spot at 9:37 PM, Monday. Also on Monday, at 9:16 PM, the moon Europa disappears behind the giant planet and reappears at 5:14 AM.

Mars rises shortly after Midnight and lies within a degree of Porrima, a bright star in Virgo. Before Dawn, Mars is high enough for observation of its northern polar ice cap. It is the Martian Spring on the northern hemisphere, and the ice cap shrinks as it melts.

Saturn rises in the pre-sunrise sky at 3:26 AM. It currently resides in Libra, moderately high in the East.

Comet Lovejoy rose before Saturn in Hercules. At the start of Dawn, it is about 25 degrees high. Internet reports still make it fifth magnitude – naked-eye observable in dark skies. The comet is about six degrees East of the star Rasalgethi, the brightest star in Hercules.

Wednesday is, of course New Year’s Day. Until 1582, the calendar Julius Caesar adopted was still in effect. It was increasingly apparent that the calendar was out of step with civil and religious seasons. A little known Italian doctor, Aloysius Lilius, wrote a letter to the Pope pointing out this problem. An initially skeptical Christopher Clavius saw the wisdom of Lilius’ solutions and championed them before the newly elected Pope. The Pope declared the reformed calendar effective on October 15, 1582. Catholic countries quickly adopted the change, even though people “lost” 10 days that year. Slowly other countries adopted it – the last being communist China in 1949. Alas, Lilius is almost forgotten, while the calendar was named for Pope Gregory and a major crater on the Moon enshrines Clavius.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, December 27, through Sunday, December 29, written by Alan French.

The Moon is past third quarter, so the evening sky is dark and moonless, and a crescent Moon is visible in the eastern sky in the morning predawn hours.

If you’re up as dawn is brightening the eastern sky, look for a thin crescent Moon in the southeast. On Sunday morning it will be below Saturn, and on Monday morning a thinner crescent will be above and to the left of reddish Antares, not far above the horizon.

Venus is now a very slender crescent and large enough to see in steadily held binoculars. The sky should be dark enough to spot Venus by 5:00 pm, when it will be 18 degrees above the southwestern horizon. It’s easier to see the crescent when the sky is still bright with evening twilight and the extreme brightness of Venus is reduced. As the sky darkens further, Venus will become more obvious and move lower toward the horizon. Venus sets at 6:50 pm.

There is a nice pass of the International Space Station (ISS) late Saturday afternoon. The times are for Schenectady, but should be close enough for anyone in the Capital District and surrounding area. For exact times for your location, based on zip code, visit http://spaceweather.com/flybys/.

The station will first appear rising up from the west northwestern horizon at 5:39 pm. It will be highest just after 5:42, when 48 degrees above the southwestern horizon, and will vanish below the southeast horizon just after 7:45.

With dark skies and a view low toward the east free of haze and clouds, Comet Lovejoy may now be faintly visible to the unaided eye, and should be a nice sight in binoculars. Look for it in the morning sky at just before 6:00 am, when the eastern sky will still be dark. The comet will be 23 degrees above the eastern horizon. It will be to the right of Vega in the constellation Hercules. Scanning the area with binoculars should pick it up. You can find a star chart showing Comet Lovejoy’s position at this web site. The crescent Moon shouldn’t be a problem, but will be thinner and not as bright on Monday morning.

The Dudley Observatory Skywatch Line for Wednesday, December 25th and Thursday, December 26th written by Louis Suarato

Venus is now an 8.7% illuminated crescent shining at magnitude -4.08. Look for Venus 15 degrees above the southwestern horizon after sunset, which occurs around 4:30 p.m. EST on Wednesday. Venus reaches inferior conjunction, which is its position between the Earth and Sun, on January 11th. Jupiter rises at approximately 5:15 p.m. in the constellation Gemini. Jupiter’s moon Europa has been in the news lately as scientists, analyzing images from the Hubble Space Telescope, discovered water vapor spouting 125 miles above. Scientists believe the geyser originated from a water source below Europa’s south pole. This finding has led to the theoretical planning of potential missions to find life forms on Europa. At 6:27 p.m. on Wednesday, the International Space Station will emerge from the west-northwest and reach an altitude of 64 degrees before disappearing in Earth’s shadow after passing Cygnus. A brighter ISS pass occurs on Thursday at 5:38 p.m. out of the NW. This -3.3 magnitude, 7 minute pass will sail through Cassiopeia and Perseus before fading after passing through Taurus. The last quarter Moon rises in the constellation Virgo 45 minutes after midnight Thursday. Look for Mars six degrees to the upper left of the Moon. Mars’ north polar cap may be visible through telescopes as it reaches it minimum phase and is 90% full. A degree to the lower left of Mars is the binary star Porrima. Porrima is comprised of two stars with magnitudes 3.65 and 3.56. Porrima’s combined magnitude is 2.9. The distance between the stars has closed, but will be wide enough again in 2020 to be seen with small telescopes. An easier binary star to split through a telescope is Castor in Gemini. The magnitudes of Castor’s brightest components are 2.0 and 2.9. Castor is actually comprised of six stars that are gravitationally bound, but only two can be easily seen. To find Castor, first find bright Jupiter rising in the east. To the left of Jupiter is Gemini’s bright star Pollux. Castor is located above Pollux. Saturn rises at 3:43 a.m. in Libra on Thursday. Saturn’s rings are tipped 22° to 23° from edge-on. Look for Saturn above the southeastern horizon before dawn.

This is the Skywatch Line for Monday and Tuesday, December 23rd and 24th by Joe Slomka.

The Sun sets at 4:25 PM; night falls at 8:08. Dawn breaks at 5:41 AM and ends with sunrise at 7:24.

The darkening sky reveals Venus glowing lower in the southwestern sky. The brilliant planet is about ten percent illuminated, but appears larger than last week. Venus sets about 6:30 PM.

Uranus, in Pisces, joins Venus in the night sky, as does Neptune, in Aquarius.

Jupiter rose during Twilight, and, by 9 PM, is high enough for observation. It is the brightest object in Gemini, shining near Pollux’s waist. The Great Red Spot, a giant storm, is visible through telescopes at 2:28 Christmas night.

The 21-day-old Moon rose at 10:40 PM Monday and shines beneath Leo’s hind feet; Wednesday’s Midnight finds it near Virgo’s head and closer to Mars.

Mars rises after Midnight and is also located in Virgo, near the star Porrima. Mars is now bright and large enough to permit amateur observations. It is now late Spring on the northern Martian hemisphere, and the northern polar ice cap is now melting.

Dawn also has Saturn glowing in Libra, low in the Southeast. Comet Lovejoy is still reported at fifth magnitude, about a degree from the star Sarin (Delta in Hercules).

Since Saturn is a feature of our night sky. Let us consider his importance. This time of the year was dedicated to Saturn, the Roman God of Harvests. A series of feasts were held during the week of the Winter Solstice – the Saturnalia. Saturn was depicted as a jolly old man. People decorated evergreen trees. Candles were lit everywhere. Houses were decorated with wreaths and Holly. Decorated cookies were baked.

People wore red peaked hats, similar to the “Santa hats” of today. Banquets were held both in honor of the harvest and wishing for a prosperous new year.

Gifts were exchanged: dolls for the children, candles and fruits for the adults. Donations and benefits were held for he poor. Saturnalia was an official government holiday. The holiday was so popular that the Christians moved the feast of Christ’s birth to compete and adopted many of the symbols and traditions of this pagan feast.

The Dudley Observatory and Albany Amateur Astronomers wish their followers Happy Holidays.

Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, December 20, through Sunday, December 22, written by Alan French.

The Moon was full last Tuesday so a waning gibbous Moon rises in the early evening hours. It rises at 7:47 pm Friday, 8:45 pm Saturday, and 9:43 on Sunday. It will reach last quarter on Christmas.

The Winter Solstice, marking the official start of winter in the northern hemisphere, occurs at 12:17 pm on Saturday. This is the day when the Sun is farthest south and appears lowest in our sky at local noon. In the southern hemisphere the Sun is at its highest at local noon and marks the start of summer.

The Sun now sets just before 4:30 pm.

Brilliant Venus continues its domination of the southwestern sky after sunset. Through a telescope Venus appears as a thin crescent. The phase can even be seen through steadily held binoculars. The best views will be when the sky is still bright with evening twilight, reducing the glare of the brilliant planet. Venus sets at 6:41 pm.

Jupiter rises in the east northeast just after sunset and is well up in the eastern sky by 10:00 pm. On Friday night the Great Red Spot, a giant storm on Jupiter, will be crossing the center of the planet at 11:14 pm. It is visible in moderate sized telescopes. Also look for the dark cloud bands crossing the planet, and notice that the planet is not round, but appears slightly flattened.

Experienced astrophotographers have had no success trying to capture images of the remains of Comet ISON. Meanwhile Comet Lovejoy, visible in the north northwest after sunset, has been very photogenic, sporting a long tail in pictures.

Comet Lovejoy is now faintly visible to the unaided eye, especially when the Moon has not yet risen, and should be a nice sight in binoculars. You can find a star chart showing Comet Lovejoy’s position at this web site. The comet is visible in the constellation Hercules just after sunset and again in the morning sky before sunrise,

By 6:00 pm the sky will be nice and dark and the Moon will still be below the eastern horizon. The comet will only by 7 degrees above the west northwestern horizon, so you’ll need a good view in that direction to spot it. (A fist held at arm’s length spans 10 degrees.)

Comet Lovejoy rises again just after 3 am and is 28 degrees above the eastern sky a 6:00 am. Unfortunately, the Moon is also in the morning sky. By next weekend Lovejoy’s morning appearance will be unhampered by bright moonlight.

The Dudley Observatory Skywatch Line for Wednesday, December 18th and Thursday, December 19th written by Louis Suarato.

The 98% illuminated, waning gibbous Moon rises on Wednesday at 5:55 p.m. EST in the constellation Gemini with its newest resident rover, China’s Jade Rabbit or “Yutu”. Yutu landed on the Moon with China’s lunar lander, Chang’e-3 in Sinus Iridium, The Bay of Rainbows, on Saturday. It is the first lunar ground exploration mission since the former USSR’s 1976 Luna 24 mission. The Moon reaches apogee on Thursday, its furthest distance from Earth this month and third most distant for this year. At apogee, the Moon will be 252,444 miles from Earth or 63.7 earth-radii. Jupiter will be 6 degrees east of the rising Moon. As the Moon and Jupiter are rising in the east-northeast, bright, crescent Venus will be setting in the southwest. As Venus is setting, so will Comet Lovejoy, just above the west-northwest horizon in the constellation Hercules. You will have a longer opportunity to view Comet Lovejoy when it rises in the east-northeast in Hercules before dawn around 4 a.m. EST. Saturn rises further east about one half hour later. Above Saturn will be Virgo’s brightest star, Spica, and above Spica is Mars. The winter months offer an opportunity to view several star clusters that be seen with the naked eye, but better viewed with binoculars. The Pleiades and Hyades star clusters can be found in Taurus, and the Beehive Cluster also known as “Praesepe”, which is Latin for manger, is in the constellation Cancer. The constellation Taurus is easy to find as it leads winter’s dominant constellation, Orion. Cancer follows the Gemini twins, and the Beehive Cluster, or M44 will be below and left of Jupiter and the Moon before midnight. M44 is one of the closest, largest and brightest of the star clusters. Eighty stars within the Beehive Cluster are brighter than 10th magnitude, and 80 are brighter than our Sun, which would appear as a 10.9 magnitude star at the distance of Praesepe. Two planets orbiting separate stars in the Beehive Cluster were discovered in September 2012. These were the first planets discovered orbiting stars like our Sun within a stellar cluster.

This is the Skywatch Line for Monday and Tuesday, December 16th and 17th by Joe Slomka.

The Sun sets at 4:22 PM; night falls at 6:05. Dawn breaks at 5:38 AM and ends with sunrise at 7:20. During twilight, Venus is the brightest object in the southwest. As the month goes on, the moderately high planet gradually becomes a thinner but larger crescent. This change is easy to follow through binoculars or small telescope. The Moon rose a few minutes before sunset. It becomes officially a Full Moon at 4:28 Tuesday morning. The natives of our region called it “The Long Night Moon.” The Moon orbits Earth with an oval orbit. Tonight’s Moon also is the furthest from Earth for the year, and also the smallest apparent size. The casual observer will not notice any difference. Twilight’s end finds Uranus and Neptune still in their yearlong positions in Pisces and Aquarius, respectively. Nightfall also witnesses Jupiter rising near Pollux’s waist in Gemini. Jupiter is the only object that withstands the Full Moon’s glare. At 8:07 PM Monday, the Great Red Spot occupies Jupiter’s center; it also is visible at 6:03 Tuesday morning. This gigantic storm is visible through most amateur telescopes. By Dawn, both Uranus and Neptune have set. Mars rises shortly after Midnight. It is about five-and-a-half degrees from the star Porrima in Virgo. Its red color should make it easy to identify. Mars grows slightly brighter and larger in telescope eyepieces. Saturn rises at 4:15 AM and glows in Libra, low on the eastern horizon. Saturn is never a boring object in telescopes; depending on telescope size, the rings and some of its 62 moons are always breathtaking. Mercury pops up shortly before sunrise. It is about three-and-a-half degrees high in the East. An unobstructed horizon is necessary to spot the brilliant, but small, planet. Comet Lovejoy replaces what would have been Comet ISON. Lovejoy is reported to be at fifth magnitude in the constellation Hercules. Naked-eye observers should be able to spot it in dark sites. Comet Lovejoy is about eight degrees below the Hercules Globular Star Cluster (M-13). M-13 is visible in binoculars, and serves as a starting point to locate the comet. This week Mars was in the headlines. Curiosity, the newest rover on the Martian surface, found traces of a three billion year-old lake. Its soil analysis revealed that the water was not acidic, potable, and contained minerals that would be useful to life. Unfortunately, Curiosity’s onboard laboratory is not equipped to hunt for evidence of life. Clear Skies

This is Dudley Observatory’s Skywatch Line for Friday, December 13, through Sunday, December 15, written by Alan French.

The Moon reaches full Tuesday, so a waxing gibbous Moon dominates the night sky over the weekend. Unfortunately, this bright Moon will interfere with the peak of the Geminid meteor shower, which occurs Friday night through Saturday morning. In spite of the Moon, an attentive sky watcher might see 20 to 30 meteors in an hour. If you’re observing in your yard, warm a quilt or some of your clothing in the drier for a while before heading outside.

Venus still dominates the southwestern sky just after sunset. On Friday night a telescope would show a crescent just less than 20 percent illuminated. Most of the sunlit face of Venus now faces away from Earth, and as Venus continues to catch up with Earth we’ll see a thinner and thinner crescent. In two weeks only 7 percent of the visible face of Venus will be in sunlight. It is a pretty sight in any telescope, and may even be detected in steadily held binoculars. The planet’s low altitude and the thick atmosphere its light travels though can impair the views, so look just as the sky is beginning to darken and as soon as you can spot Venus.

The International Space Station will make a nice pass over the Capital District area late Saturday afternoon, just over 70 minutes after sunset. We see satellites because they are still up in sunlight while we are down in the Earth’s shadow. During this pass you’ll have a chance to see the ISS move out of the sunlight and into the Earth’s shadow and fade from view.

Because it is very large the ISS is very bright, outshining all the stars and approaching the brightness of Venus. It is easy to sport, especially once it has risen well above the horizon. Just look for a bright star gliding across the heavens. Times will be given in hours, minutes, and seconds. They are for Schenectady, but should be close enough for anyone in the Capital District area.

The ISS will first appear coming up from the west southwestern horizon at 5:33:21 pm. I usually spot it somewhat after the “first appearance time,” when it has risen a bit higher into the sky. It will be highest at 5:36:33 pm when it will be 45 degrees above the north northwestern horizon, and will move into the Earth’s shadow and fade from view at 5:38:28 when 21 degrees above the northeastern horizon. How long can you follow it after it starts fading?

Its path will take it just below Vega, the brightest star in Lyra, the Lyre, through Draco the Draco, and close to Polaris the North Stat. The space station will move into the Earth’s shadow and fade from view as it moves down toward the northeastern horizon.

The Dudley Observatory Skywatch Line for Wednesday, December 11th and Thursday, December 12th written by Louis Suarato

December 11th is the birth date of Annie Jump Cannon, a deaf astronomer who classified stars by spectral classes of their surface temperature. Born in 1863, Cannon catalogued over 225,000 stars for the Henry Draper Catalogue of Stellar Spectra. The spectrum classifications consisted of the letters O, B, A, F, G, K, M with “O” being the hottest atmospheric temperature of greater than 33,000 degrees Kelvin and “M” being the lowest atmospheric temperature between 2,600 degrees Kelvin and 3,850 degrees Kelvin. An example of an O spectral, or Blue Star, is Iota Orionis, the bright star at the end of the sword in the constellation Orion. An example of an M spectral or Red Star, is Betelgeuse, also in Orion. You can see Orion above the eastern horizon after 7 p.m. EST. Jupiter will be rising to Orion’s east in the constellation Gemini. At 8:30 p.m., the shadow of Jupiter’s moon Europa begins its transit. The Great Red Spot transits at 11 p.m. EST. Try to make out Venus’ crescent shape with binoculars before it sets in the southwest before 7 p.m. EST. The 72% illuminated, waxing gibbous Moon rises at 12:59 p.m. EST Wednesday afternoon. After sunset, the Moon will be high in the southeast in the constellation Pisces. At 11 p.m., the Moon will be 3.3 degrees to the north-northwest of Uranus. Mars rises in Virgo around 1 a.m. Thursday. Saturn rises in the pre-dawn sky at 4:30 in Libra. Be on the lookout for some early Geminid meteors. The Geminid Meteor Shower peaks this Friday night into Saturday morning. Although the Moon will be nearly full, the Geminids contain bright meteors and can be seen despite the moonlight.

This is the Skywatch Line for Monday and Tuesday, December ninth and tenth by Joe Slomka.

The Sun sets at 4:21 PM; night falls at 6:03. Dawn breaks at 5:33 AM and ends with sunrise at 7:15.

The First Quarter Moon glows moderately high in southern skies; at 6:05, it is due South. Tuesday’s Moon snuggles up to Uranus, only four degrees away. Both set after Midnight.

Venus, the next brightest object, lies lower in the southwest. Its brilliance makes identification easy. Telescopes reveal it about 23 percent illuminated. Venus sets at 7:06 PM.

Nightfall shows Neptune in dim Aquarius. Astronomy magazines, websites and apps provide finder charts. Neptune sets at 10:20 PM.

Jupiter rose at 6:29 PM, and remains up all night. Jupiter is the brightest object in Gemini, by Pollux’s knee. Binocular and telescopic observers can witness the Jovian moon Ganymede disappear at 11:13 Monday night, and reappear at 5:01 Tuesday morning. Wednesday morning at 3:34, early birds can telescopically observe the moon Io’s shadow begin to cross the giant planet’s face, and end its trek at 4:11 AM.

Mars ascends from the East at 38 minutes after midnight and is found in Virgo’s head. Saturn joins the pre-dawn scene at 4:38 AM in the low southeastern constellation of Libra.

Mercury rises above the eastern horizon at 6:26 AM. At minus 0.7 magnitude, it appears like a brilliant star. Telescopes show it almost “full.”

By 10 PM, Gemini is high in the southeastern sky, along with Orion and Canis Major. Sky watchers should notice enhanced meteor activity. This is the annual Geminid meteor shower. The shower peaks Friday night. Meteors seem to stream from the twin stars Castor and Pollux. Under ideal conditions and a dark sky, one can see 120 meteors per hour. The Moon’s glare diminishes the number of meteors; only the brightest will be detected. Light pollution further reduces these numbers.

Most meteor showers are the result of comet litter. But, the Geminids are the result of a three-mile long asteroid, Phaeton - the only known asteroid generated meteor shower.

Last week, we witnessed the disintegration of Comet ISON as it looped around the Sun. Recently, UCLA astronomers discovered that Phaeton suffers similarly from the Sun. Its close proximity to solar heat bakes Phaeton’s rocks, which crumble and shed, just like a comet’s ices.

If comet hunters go out at 5 AM, Comet Lovejoy lies about 6 degrees from M13, in Hercules. Reported about fifth magnitude, it can be seen in binoculars, and with the naked eye under dark skies.

This is Dudley Observatory’s Skywatch Line for Friday, December 6, through Sunday, December 8, written by Alan French.

Comet ISON was essentially destroyed as it passed close to the Sun on Thanksgiving, and is now just an expanding and fading cloud of gas and dust. It is not expected to be visible at all. At best, it may be a challenging target for experienced astrophotographers, and they’re probably working hard to be the first to capture an image of its remains. It will be interesting to see if anyone is successful.

Although Comet ISON turned into a dud, it was exciting watching it passing close to the Sun, almost in real time via the Internet, and then see its remnants emerge from behind the camera’s occulting disk and dissipate and fade. Scientists will certainly learn a lot from this comet, even if it didn’t put on the show we had hoped for. Alas, early predictions of Great Comets are unrelenting victims of reality. This writer hopes that future media coverage of comets will reserve the terms “Great Comet” and “Comet of the Century” for use only after a comet performs accordingly.

The Moon was new last Monday and reaches first quarter this coming Monday. Just after sunset on Friday night look for the crescent Moon in the south southwest, with brilliant Venus to the Moon’s lower right. The Moon will set at 8:55 pm. By Saturday night a fatter crescent will be higher and farther toward the south, and set at 10:06 pm. Moonset on Sunday night is at 11:16 pm.

Weather permitting; the Albany Area Amateur Astronomers will hold public star party at Landis Arboretum in Esperance at 8:00 pm on Friday and Saturday, December 6 and 7. A variety of telescopes will be set up by club members to provide guests with views of star clusters, nebulae, galaxies, double stars, and other celestial sights. Star parties are open to all and there is no admission fee. There will be a short introductory program in front of the meeting house. For those interested, there will also be a tour of the fall constellations.

Star parties last at least an hour and usually go much longer if the skies are clear. You are welcome to stay as long or as briefly as you like. Be sure to dress warmly. It feels 20 to 30 degrees colder when you are standing under clear night skies. Having extra warm clothing on hand is better than being uncomfortable.

For directions to Landis Arboretum see this link. The star party will be canceled if the skies are mostly cloudy. If in doubt, call 374-8460.

The Dudley Observatory Skywatch Line for Wednesday, December 4th and Thursday, December 5th written by Louis Suarato

Look to the southwestern horizon after sunset on Wednesday to see the 5% illuminated, waxing crescent Moon about 16 degrees to the west and below bright Venus. The Moon is at perigee, its closest distance to the Earth for the month, at 56.45 earth-radii or 223,856 miles. Lunar perigee occurs only 9 hours after New Moon, so expect higher than normal tides. Venus is becoming a thinner crescent, but is closing in on Earth, and reaches its greatest brilliancy on Friday. Venus will remain at magnitude -4.9 until December 17th. Thursday evening, the Moon will be 7.5 degrees north of Venus. The two brightest planets, Venus and Jupiter, can be seen simultaneously in the evening sky. Jupiter rises just before 7 p.m. EST in the constellation Gemini to the east of Orion. Jupiter’s Great Red Spot transits at 8:06 p.m. EST. Jupiter’s moon Io begins its transit at 11 p.m. followed by its shadow a half hour later. Mars rises 45 minutes after midnight in Virgo and forms a triangle with Virgo’s brightest star, Spica, and Bootes brightest star, Arturus, before dawn. Mars’ brightness increases from magnitude +1.2 to +0.9 during December. Comet Lovejoy can be seen easily with binoculars before dawn by tracing a line from Arcturus through the two stars forming the flat side of kite shaped Bootes, beyond the last star by about 7 degrees. Saturn rises just before 5 a.m. in the constellation Libra. Mercury is 10 degrees below Saturn, but may be lost in the Sun’s glow. Take advantage of the moonless night to view M34, an open star cluster in Perseus. M34 is approximately 1,800 light-years away and is about the width of the Full Moon visually, although it spans 15 light years physically. Consisting of about 100 stars ranging from magnitude +7.9 down, and having a visual magnitude of +5.5, M34 can be seen using binoculars. To find M34, look about 20 degrees above the Pleiades star cluster. M34 will be east of Perseus’ brightest star, Mirphak. The Double Cluster will be to M34’s north, toward Cassiopeia. This weekend, the Albany Amateur Astronomers will be hosting star parties on Friday and Saturday evening at the George Landis Arboretum in Esperance, NY. Directions to the Arboretum can be found at http://landislive.weebly.com/hours--directions.html.

This is the Skywatch Line for Monday and Tuesday, December second and third written by Joe Slomka.

The Sun sets at 4:22 PM; night falls at 6:03. Dawn breaks at 5:27 AM, ending with sunrise at 7:08.

Monday’s sunset finds only Venus visible. Through December, Venus grows brighter, longer and thinner. Monday evening it is nineteen degrees above the horizon; binoculars or telescope shows it to be a third illuminated. Venus sets at 7:12 PM.

Shortly after Monday’s nightfall, the Moon turned “New.” Tuesday’s civil twilight exhibits a very thin lunar crescent eight degrees above the southwestern horizon. This one-day-old Moon presents a challenge to observers, since it is low and sets at 5:23 PM.

Uranus and Neptune remain in Pisces and Aquarius. Astronomy magazines, websites and apps provide observing guides. Neptune sets at 10:47 PM, Uranus at 1:52 AM.

Jupiter rises about 7 PM and, by 9, is high enough for observation. The giant planet continues to glow near the knee of Pollux, one of the twin stars in Gemini. Midnight sees Leo, the Lion, rise high enough for observation. Leo contains a challenge object, Comet Nevski. The comet is named for one of the co-discoverers of Comet ISON. ISON was found in 2012, while this new comet was located in 2013. Nevski, at fifteenth magnitude, is a challenge object for people with large telescopes. Comet Nevski is about six degrees above Regulus, Leo’s brightest star.

Mars rises after Midnight, residing below Leo’s tail and within Virgo’s head. Mars is easily identified by its distinctive orange color; it brightens slightly this month.

Saturn, rising before Dawn, in Libra, is fourteen degrees above the horizon. Mercury also rises during Dawn. It is the brightest object in the Southeast, about 10 degrees below Saturn on Tuesday, and 11 degrees below on Wednesday.

The pre-Dawn sky is busy with comets. Besides faint Comet Nevski in Leo, there is a binocular comet. It is named Comet Lovejoy. At eighth magnitude, it should be a blur in binoculars and finder telescopes. It is located about three-and-a-half degrees east of the star Nekkar, the top star in Bootes. Again astronomy magazines, websites and apps provide charts.

The comet that everybody is interested in, Comet ISON, is still uncertain. The comet attempted to swing around the Sun on Thanksgiving afternoon. Webcasts depicted the comet entering the Sun’s glare, but failed to emerge. Professional astronomers were pessimistic. However, later satellite images indicated a tiny fragment survived. It is unknown whether that fragment will be visible to amateurs. Check astronomy websites for updated information

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This is Dudley Observatory’s Skywatch Line for Friday, November 29, through Sunday, December 1, written by Alan French. .

The Moon reached last quarter this past Monday and is now moving toward new, which occurs late Monday. On Saturday morning a slender crescent Moon will be visible low in the southeast as dawn breaks, about midway between Spica, the brightest star in Virgo, the Virgin, and Saturn. By Sunday a thin crescent will be low in the south southeast just before sunrise, with Saturn above the Moon and Mercury well to its lower left.

You’ll need a good view to the south southeast to spot the trio around 6:00 am. By 6:30 they will be higher, but the increasing twilight glow will make the two planets harder to spot. Mercury is more than a magnitude brighter than Saturn, but deeper into the twilight glow. Which planet can you follow the longest?

Brilliant Venus continues to linger low in the southwestern sky just after sunset. Even a modest telescope will reveal it as a fat crescent. Its brilliance and low altitude, with the telescope looking through a thick layer of image distorting atmosphere, will likely result in a shimmering view of our sister planet, probably with some dancing colors around it. Most refracting telescopes do not focus the blue and red ends of the spectrum well, so such a bright target will be surrounded by a purplish glow. Add the thick atmosphere acting like a prism on bright Venus, and it can be a bit like looking through a kaleidoscope.

Venus is now rapidly catching up with Earth as it travels around the Sun on its faster, inner orbit. As it catches up, it grows in apparent size and we see less and less of its sunlit face. By the end of December Venus will be a thin crescent very low in the west southwest just after sunset, and the crescent will be large enough to see in steadily held binoculars.

If you have an aspiring astronomer on your gift list, there are some excellent introductions to the night sky and amateur astronomy. Terence Dickinson’s “Nightwatch” is one of the best. Dickinson, with Alan Dyer, also authored “The Backyard Astronomer’s Guide,” which provides a more thorough and technical introduction. Both books have excellent coverage of the tools of amateur astronomy and the sights that can be enjoyed in the night sky.

Perhaps that aspiring astronomer is a youngster. If so, you’ll find some excellent suggestions at "Books for Young Astronomers". .

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The Dudley Observatory Skywatch Line for Wednesday, November 27th and Thursday, November 28th written by Louis Suarato.

The 22% illuminated, waning crescent Moon sets at 1:36 p.m. EST on Wednesday. Crescent Venus, now shining at magnitude -4.33, can be easily seen approximately 15 degrees above the southwestern horizon in the constellation Sagittarius after sunset. Jupiter rises around 7:20 p.m. in Gemini, at the same time the Great Red Spot begins its transit across the gas giant planet. Jupiter’s moon, Io, is eclipsed by the planet’s shadow at 9:04 p.m. EST. Mars rises at 1 a.m. Thursday in Virgo, followed by the Moon approximately one hour later. Comet Lovejoy, now shining at magnitude 7.99, can be found above the northeastern horizon before dawn on Thursday, by extending the arc of the Big Dipper’s handle approximately 10 degrees, or the width of a fist at arm’s length. Comet Lovejoy made its closest approach to Earth at a distance of 36.8 million miles on November 19th. Comet Lovejoy is expected to reach magnitude 4.5 and reaches perihelion on December 22nd at a distance of .81 astronomical units (AU) from the Sun. One astronomical unit is the average distance of the Earth to the Sun. The comet that has been the focus of the most interest is Comet ISON. Comet ISON reaches perihelion on Thursday at approximately 2 p.m. EST, about 730,000 miles from the Sun. As Comet ISON catapults around the Sun, it will reach a speed of 845,000 miles per hour. Its closest approach to Earth will be 28 million miles on December 28th. The Great Comet of 1680 was seen at noon, 2 degrees from the Sun, on its perihelion, as its tail grew 70 to 90 degrees long!

There are three possible scenarios for the destiny of Comet ISON.


1. Comet ISON may disintegrate sometime before perihelion. It may occur while lost in the glow or too close to the Sun to see, but NASA’s satellites will record the event and obtain valuable data.


2. At Comet ISON’s closest approach to the Sun, temperatures will reach 5,000 degrees Fahrenheit. The Sun’s heat could vaporize the comet or the Sun’s gravity could pull it apart.


3. Comet ISON could survive its trip around the Sun sporting a loooong tail for all to see!

If Comet ISON does survive its trek around the Sun, it will appear in the evening sky around mid-December.

This is the Skywatch Line for Monday and Tuesday, November 25th and 26th written by Joe Slomka.

The Sun sets at 4:25 PM; night falls at 6:05. Dawn breaks at 5:21 AM and ends with sunrise at 7:01.
As the Sun sets Venus is the sole visible planet. Moderately low in the southwest, Venus blazes at -4.6 magnitude and appears about one-third illuminated in large binoculars or telescopes. Nightfall finds Venus joined by Neptune and Uranus. Neptune still appears in Aquarius, and Uranus remains in Pisces. Astronomy magazines, websites and apps provide observing maps. Venus sets about 7:14 PM. Jupiter rises around 7:30 PM, and, by 9, is high enough for observation. Binocular observers can see the moon Ganymede disappear into Jupiter’s shadow at 10:11 PM Monday. Telescopic sky watchers can witness, on Tuesday, at 11:47 PM, the moon Io’s shadow beginning to cross Jupiter’s face, followed by Io itself marching across the planet at 12:40 AM.

The Last Quarter Moon rises at 11:55 PM Tuesday, and 12:53 AM Wednesday. Mars rises shortly after the Moon and appears between Leo’s hind leg and Virgo’s head. Last Monday, NASA launched MAVEN, a space probe that will study Mars for clues as to why its atmosphere virtually vanished.

By Dawn, Comets Lovejoy and Nevski appear in northern skies. Lovejoy appears as an eighth magnitude blur six-and-a-half degrees below the Big Dipper’s handle; do not mistake it for two nearby galaxies. Comet Nevski is a tenth magnitude haze about five degrees above the star Regulus in Leo. Both are borderline binocular objects, and definitely visible in telescopes. Saturn and Mercury emerge from the Sun’s glare at Dawn and can be spotted low in the Southeast. The two planets are about ten degrees above the horizon and separated by a third of a degree. Both will fit in binoculars or a finder telescope. Mercury is brighter and below Saturn. Training a telescope reveals Saturn and its rings, while Mercury is half Saturn’s size and about 82 percent illuminated. This is Mercury’s best appearance in our northern sky for the year.

Comet ISON lies about ten degrees below the Saturn-Mercury duo. ISON is very low on the horizon, requiring a view free of obstruction. In addition, the comet rises about 6:24 AM and is soon lost in the Sun’s glare. In three days, ISON will approach and try to swing around the Sun. Astronomers are uncertain if the comet will survive to appear in our morning sky.

This is Dudley Observatory’s Skywatch Line for Friday, November 22, through Monday morning, November 25, written by Alan French.

Comet ISON is now very low in the south southeast, rising just after dawn breaks, and competing with the increasing glow of morning twilight as it rises higher. Look for it at 6:00 am Saturday morning, when it will be the lower right of Mercury. Mercury will be just 6.5 degrees above the horizon and you’ll need a good clear view to the south southeast free of clouds and haze. Binoculars may aid in the search for the comet. From Mercury, Comet ISON will be at about four o’clock, and five degrees away. (A fist held at arms length spans 10 degrees across the knuckles.) Also note Saturn to the lower left of Mercury.

By Sunday morning ISON will only be 1.5 degrees above the horizon at 6:00 am, at the 5 o’clock position from Mercury. By 6:30 it will have risen to 6 degrees, but the eastern sky will be brighter. Look at 6:30 am Monday. ISON will be just over 3.5 degrees above the horizon, and a bit right of directly below Mercury. It may be swallowed by the glow of encroaching dawn, but we could also be pleasantly surprised.

While much news has been focused on Comet ISON, Comet Lovejoy is quite nice in binoculars and faintly visible by eye. Lovejoy is also high in the sky and near the well know pattern of stars know as the Big Dipper (part of the constellation Ursa Major or the Great Bear).

Look for the Dipper high in the east around 5:00 am. You’ll see the Dipper standing upright on its handle. On Saturday morning, aim your binoculars between the middle two stars in the handle, and then scan to the right. You should soon come to a conspicuous ball of light. This is the head of Lovejoy. If you look carefully, you may see a faint tail going upward. If you are familiar with the sky, you can also find the comet by looking just to the left of the upper star in Canes Venatici, the Hunting Dogs.

If you go out Sunday morning at 5:00 am, start by aiming your binoculars between the two end stars in the handle, and scan to the right. On Monday start just above the end star in the handle and move to the right. On Monday, Comet Lovejoy will be half way between the end star in the Dipper’s handle, and Cor Caroli, the brightest star in Canes Venatici. Cor Caroli will be the most obvious star to the right of the Big Dipper’s handle.

It may be possible to spot Comet Lovejoy by eye alone. This writer could see it on Wednesday morning, even with a bright Moon in the sky. The Moon is getting fainter every night, but it is also moving closer to Lovejoy’s position in the sky.

Comets are unpredictable, so it’s worth keeping an eye on them, especially ISON as it moves closer to the Sun.

The Dudley Observatory Skywatch Line for Wednesday, November 20th and Thursday, November 21st written by Louis Suarato

“Equipped with his five senses, man explores the universe around him and calls the adventure science.” – Edwin Hubble, born November 20, 1889

With the distant images now provided by the Hubble Space Telescope, it’s amazing to think that as recent as one hundred years ago, it was thought that the known universe consisted of one galaxy, our Milky Way. It was Edwin Hubble, who in 1924, looking through the 100-inch Hooker Telescope on Mount Wilson, changed that perception. Hubble observed many other galaxies, all moving away from each other. Through these observations, Hubble provided the first evidence of the expanding universe and the theory the universe had began at a single point, known as “The Big Bang Theory”.

The closest galaxy to our Milky Way is Andromeda, or M31. The Andromeda Galaxy can be seen with the naked eye, and at approximately 2.5 million light years away, is the farthest object that can be seen unaided. Andromeda’s apparent magnitude, a measure of brightness as seen from Earth without the interference of atmosphere, is 3.44. Although distant, Andromeda’s brightness is a factor of its estimated billions of stars and its size. Andromeda is 120,000 light years across. You can locate the Andromeda Galaxy by drawing a line from Polaris, the North Star, through the deep “V” in Cassiopeia, which is the star, Shedir, and continue about 3 extended fist lengths, or approximately 30 degrees, to Andromeda. At 6 p.m. EST Wednesday evening, Andromeda will be about 55 degrees above the eastern horizon. At the same time, Venus will be setting over the southwestern horizon.

The 90% illuminated, waning gibbous Moon rises at 7:09 p.m. in the constellation Gemini. Look for Jupiter to the Moon’s lower left. Thursday night, around midnight, the Moon passes 5 degrees south of Jupiter. Jupiter’s moon, Io, will reappear from behind the planet at 11:27 p.m. Wednesday night. On Thursday, Io, and its shadow can be seen crossing Jupiter below the Great Red Spot at 6 p.m., and Europa will disappear into the planet’s shadow at 7:09 p.m. EST.

Mars rises at 1 a.m. on Thursday. Before dawn, Virgo’s brightest star Spica, will rise at approximately 4:30 followed by Mercury and Saturn. You will require a clear east-southeastern horizon to see Comet ISON above and to the right of Mercury. This could be one of the last opportunities to see Comet ISON before it is lost in the Sun’s glow and onto its uncertain future.

On Friday, November 22nd at 7 p.m., the Dudley Observatory will be hosting a discussion and update on Comet ISON followed by a Star Party at the Octagonal Barn. Directions to the barn in Delanson, NY can be found at http://www.dudleyobservatory.org/index.html.

This is the Skywatch Line for Monday and Tuesday, November 18th and 19th written by Joe Slomka .

The Sun sets at 4:30 PM; night falls at 8:08. Dawn breaks at 5:13 AM and ends with sunrise at 6:52.


Venus is the only bright planet in the darkening sky. It is found moderately low in the South. In binoculars and telescopes, Venus grows brighter and larger, but presents a slimmer crescent. At nightfall, Venus appears very close to the star Nunki, in Sagittarius. Venus sets at 7:12 PM.


Nightfall also witnesses the Milky Way arch overhead from northeast to southwest. However, the view will not last long. The Moon, one day past “Full,” rises at 5:30 PM and soon overwhelms the dimmer stars. Uranus and Neptune also become visible at this time. They remain in Pisces and Aquarius, respectively. Astronomy magazines, websites and apps provide observing guides.

By 9 PM, the Moon is moderately high between the horns of Taurus, the Bull. Tuesday finds the Moon near the tip of the lower horn. The annual Leonid meteor shower peaked Sunday; however, the Moon’s brilliance will probably render all but the brightest fireballs invisible.


Jupiter rose at 8 PM and is found near Pollux’s knee, in Gemini. By Midnight, Jupiter is well placed for observation. At 12:40 AM, binocular and telescopic observers can witness the moon Io disappear into Jupiter’s shadow and reappear at 4 AM. Wednesday, at 12:08 AM, Io emerges from the Jovian shadow, followed by Europa’s shadow beginning to cross Jupiter at 12:44 AM.


Mars rose after 1 AM and, by Dawn, is high enough for observation. Mars also brightens and grows slightly larger. The Red Planet appears near Leo’s hind leg.

As mentioned last week, four comets are in the Dawn sky. Two have brightened, and two are now very challenging. Comet Lovejoy has brightened to 6.5 magnitude, making it borderline naked eye visible. Binocular users can see it near the hind leg of Ursa Major, the Great Bear. Comet ISON also shines brighter, at magnitude 7.5. This makes it also easier for binocular and telescope users. ISON lies about eight degrees below the bright star Spica in Virgo. Reports say ISON has doubled the length of its tail, and also sports a second tail. Some Capital District binocular observers saw Comet ISON Friday morning from semirural towns. Comet LINEAR is difficult, due to its dim thirteenth magnitude. Comet Encke is too low to be seen.

 

This is Dudley Observatory’s Skywatch Line for Friday, November 15, through Sunday, November 17, written by Alan French.

Reaching full on Sunday, a bright waxing gibbous Moon will dominate the night sky on Friday and Saturday nights. Look for the Moon low toward the east as darkness falls. The full Moon of November is called the Beaver Moon or the Frost Moon – the Beaver Moon because this was the last chance to set traps before streams and ponds froze over.

It’s fun to watch the full Moon rising over a distant horizon. It often appears orange or even red. Our atmosphere scatters the blue end of the spectrum, which is why the sky is blue. Down near the horizon, where the light passes through a thicker layer of atmosphere, there is even more scattering and loss of light toward the blue, and the resulting predominance of red, orange, and yellow light colors the rising Moon. The full Moon rises at 4:51 pm in the east northeast on Sunday.

Near the horizon, the Moon often appears unusually large. This is purely an illusion. It has often been attributed to its proximity to objects on the horizon, but the illusion persists over an ocean or desert horizon. Even the constellations look larger when near the horizon.

Brilliant Venus, now shining at magnitude -4.5, continues to dominate the southwestern sky just after sunset. Venus is 9 degrees above the horizon at 6:00 pm and sets at 7:11. A telescope would reveal Venus appears a little less than half full.

Bright Jupiter rises in the north northeast at 8:12 pm. By 11 pm the gas giant is just over 28 degrees above the horizon and a good object for telescopic observations. Even a modest telescope will show some dark bands crossing the planet. Most obvious are the dark north and south equatorial belts, above and below the lighter equatorial zone. The darker north and south polar regions are also fairly easy to see. Jupiter is best seen when due south and highest, when we look through a thinner lawyer of atmosphere. Right now, this is at 3:46 am, when Jupiter will be just less than 70 degrees above the horizon.

Any telescope will show Jupiter’s four largest moons, appearing as stars to either side of the planet. These moons, Io, Europa, Ganymede, and Callisto, were discovered in 1610 by Galileo, who was the first to aim a telescope at the night sky and record his observations. They are often called the Galilean moons. The rest of Jupiter’s 66 moons are beyond the visual reach of amateur telescopes.

The Dudley Observatory Skywatch Line for Wednesday, November 13th and Thursday, November 14th written by Louis Suarato

The 85% illuminated, waxing gibbous Moon rises at 2:24 p.m. EST on Wednesday. At 10 p.m., the Moon passes 3 degrees north of Uranus in the constellation Pisces. Shining at magnitude 5.7, Uranus is the faintest of the planets visible to the naked eye. With the bright Moon close by, binoculars will provide a better view of Uranus, or waiting until the Moon is no longer an impediment. Sir William Herschel discovered Uranus in March of 1781 using a 160mm reflector telescope while looking for binary stars. Herschel, at first thought the fuzzy disk was a comet, until he observed the speed at which the planet moved against the background stars. Other astronomers, like John Flamsteed, had observed Uranus before Herschel, but categorized the planet incorrectly as a star. Sky and Telescope provides charts for finding Uranus and Neptune for the remaining of 2013 and throughout 2014. You can find the charts by accessing the following URL: http://www.skyandtelescope.com/observing/highlights/Uranus-and-Neptune-in-2013-190064991.html

After sunset, look approximately 15 degrees above the southwestern horizon for bright Venus. Venus’ 42% illuminated, waning crescent disk can be seen through binoculars or small telescopes. As Venus is setting, the Pleiades star cluster is rising in the east in the constellation Taurus. To the north of the Pleiades is Auriga’s brightest star, and the third brightest star in the northern celestial hemisphere, Capella. Appearing to be a single star to the naked eye, golden-yellow Capella is actually a pair of binary stars, but the stars are too close to be split by most telescopes. The separation was first observed by J.A. Anderson using the 100-inch telescope at Mt. Wilson. Capella is the closest of the first magnitude stars to the northern pole.


Jupiter rises at 8:20 p.m. EST in the Gemini, to the lower right of the constellations brightest stars, Castor and Pollux. Mars rises below the constellation Leo at 1 a.m. EST Thursday. Comet ISON is now approximately 20 degrees below Mars and 10 degrees above Spica, the brightest star in the constellation Virgo. Mercury rises at 5:30 a.m. and can be seen to the lower left of Spica.

This is the Skywatch Line for Monday and Tuesday, November 11th and 12th, 2013 by Joe Slomka

The Sun sets at 4:36 PM; night falls at 6:13. Dawn breaks at 5:06 AM and ends with sunrise at 6:43.

The nine-day-old Moon rose in early afternoon Monday, and by civil twilight, is the brightest object in the southeastern sky; Tuesday’s Moon appears about three-quarters illuminated.

Venus, the next brightest, glows moderately low in the southwestern constellation of Sagittarius and sets after 7 PM.

Civil twilight finds Neptune and Uranus in Aquarius and Pisces, respectively. However, the brilliant Moon nearby will probably overwhelm these distant members of our Solar System. Jupiter rose at 8:27 PM and hovers near Pollux’s knee in Gemini. By 10 PM, Jupiter is high enough for observation. Telescope observers can witness the moon Io’s disappearance behind Jupiter at 10:47 PM and see it reappear at 2:11 Tuesday morning.

Comet Lovejoy rises after 10 PM and, by Midnight, should be high enough for observation. Internet reports are that it is about eighth magnitude near Leo’s nose – bright enough for telescopic views.

By Dawn, Mars is 40 degrees high, near Leo’s hind feet. Mars is starting to become bigger and brighter in our telescopes. Besides Mars and Jupiter, Comet Lovejoy, as mentioned, is reportedly visible, as is ninth magnitude Comet ISON about three-and-a-half degrees West of Virgo’s star Porrima, Comet Linear three degrees from Arcturus in Bootes and Comet Encke six-and-half degrees from Spica in Virgo. Observing aids for these comets can be found in astronomy magazines and websites.

Although the Chelyabinsk meteor happened this past February 15th, repercussions continue through the scientific community. The meteor was far bigger than originally estimated – now at 19 meters (62 feet) – and weighing at 12,000 metric tons. As it blazed in the morning sky, it shone 30 times brighter than the Sun and sent shockwaves 30 kilometers in diameter. The event forced astronomers to drastically revise their estimates of how frequently asteroids hit earth; now they say about every 25 years. If that is true, how did we miss witnessing so many? The answer is that since Earth is 70 percent water, most splashed harmlessly into oceans. The US already has a search for potentially harmful asteroids. However, they were concentrating on large bodies, not bus-sized rocks. Now NASA and others are planning to widen their searches for Chelyabinsk-sized rocks as well as mountain-sized ones.

 

This is Dudley Observatory’s Skywatch Line for Friday, November 8, through Sunday, November 10, written by Alan French.

Dudley Observatory will hold a Skywatch Lecture and Urban Star Party on Friday evening at miSci. At 7:00 pm Dr. Harry Ringermacher will speak on “Discovering Planets around Other Suns.” Weather permitting; his talk will be followed at 8:00 pm by an Urban Star Party, with telescopes set up on the museum patio to provide guests with views of celestial sights. A donation of $5 to $10 is suggested for this event.

For further details, visit Dudley Observatory's Website.

The Moon reaches first quarter very early Sunday, so the early evening sky will be graced by a waxing Moon. As darkness falls Friday night, a fat crescent Moon will be in the south southwest. Moonset is just before 10 pm. By Saturday night the Moon will be toward the south as darkness falls, and the Moon will be a little less than half illuminated. It will set just after 11 pm. Sunday’s Moon will be a bit more than half full, and set after midnight.

This weekend would be an ideal time to turn a telescope toward the Moon. Craters and mountains are most prominent along the terminator, the line dividing the sunlit and dark portions of the Moon. This is the sunrise line now, where the Sun is low in the lunar sky and shadows are longest, bringing details into bold relief.

Venus continues to dominate the southwestern sky just after sunset; It sits just over eight degrees above the horizon at 6:00 pm and sets at 7:08 pm. Venus is the second brightest object in our night sky, only the Moon is brighter. This evening appearance of Venus sees the planet moving unusually far south, and never getting very high above the horizon.

Venus is sometimes called our “Sister Planet,” because it is our closest planetary neighbor and similar is size and composition to our Earth. Conditions on its surface, however, are quite different. The atmospheric pressure is almost 100 times that of Earth. It is the hottest planet in our solar system, with a mean surface temperature over 850 degrees Fahrenheit.

The weather did not cooperate with the sunrise partial solar eclipse on November 3 and I have heard not reports of anyone seeing it from the Capital District region. It was, however, visible from New York City and photographer Chris Cook’s took a wonderful photograph. From here, the Moon would have covered a bit less of the Sun.

The Dudley Observatory Skywatch Line for Wednesday, November 6th and Thursday, November 7th written by Louis Suarato

On November 6, 1572, Wolfgang Schuler observed a supernova in the constellation Cassiopeia. The supernova was noticed on November 11th by Tycho Brahe, who began to record the appearance. Brahe’s observations led to the book that gained him fame, “Stella Nova”. For weeks, this new star was brighter than any other in the sky and visible in daytime. Brahe wrote of the new supernova, “I noticed that a new and unusual star, surpassing all others in brilliancy, was shining almost directly over my head; and since I had, almost from boyhood, known all the stars of the heavens perfectly, it was quite evident to me that there had never before been any star in that place in the sky, even the smallest, to say nothing of a star so conspicuously bright as this.”. Recently, 10 year old Canadian, Nathan Gray, discovered a 600 million year old supernova in the constellation Draco, making Nathan the youngest to discover a supernova. Nathan’s sister also discovered a supernova when she was 10, and only 33 days older than when Nathan discovered his supernova. Supernovae occur when a star culminates in an explosion at the end of its stellar life. A supernova hasn’t been observed in our galaxy since Kepler’s Star in 1604, but remnants indicate a supernova occurs in the Milky Way about three times each century, and some astronomers have predicted that supernova within the Milky Way galaxy may be visible in the next 50 years.

On Wednesday, the Moon reaches perigee, its closest distance from Earth this month, at 57.28 earth-radii or 227,094 miles away. After sunset, look above the southwestern horizon for the 15% illuminated, waxing crescent Moon, approximately 7 degrees to the upper right of Venus. If you are fortunate to be under dark skies, Venus will appear to be steaming from Sagittarius’ Teapot asterism. According to Sky & Telescope, on Thursday, Venus will reach its farthest southern declination (-27° 10’) since 1930. Venus will not be this far south until November 2021. Jupiter rises minutes before 9 p.m. EST in the constellation Gemini. On Thursday at 2 p.m. EST, Jupiter will be stationary and begins its westward or retrograde motion as the Earth catches up to Jupiter in its orbit. As we pass Jupiter and look back at the giant planet, it will appear to make a loop against the background stars over the next four months. Mars rises at 1:17 p.m. EST on Thursday.

The Dudley Observatory invites you to join them at their new home in the Museum of Innovation and Science (miSci) in Schenectady on Friday, November 8th at 7 p.m., for a Skywatch Lecture by Dr. Harry Ringermacher. Dr. Ringermacher’s topic will be “Discovering Planets Around Other Suns”.

This is the Skywatch Line for Monday and Tuesday, November 4th and 5th.

Now that Standard Time is back in effect, the Sun sets at 4:44 PM; night falls at 6:20. Dawn begins at 4:58 AM and ends with sunrise taking place at 6:35.

As the sky darkens, Venus is the brightest object in the southwestern sky. Observing with a telescope just after sunset, a person could see that Venus is about half illuminated. This month, Venus grows brighter and larger, but presents an increasingly slimmer crescent. Venus is at the greatest separation from the Sun, and the lowest in the sky since 1930. Venus sets after 7 PM.

Monday’s Moon, usually the brightest object in the sky, takes second place. At -1 magnitude, Venus easily outshines it with -4.4 magnitude. Monday night, the two-day-old Moon hugs the southwestern horizon; Tuesday finds it closer to Venus, fatter and slightly brighter than Venus.

Nightfall witnesses Neptune and Uranus at their usual stations in Aquarius and Pisces. Astronomy magazines, websites and apps provide finder charts.

If the sky watcher sees meteors coming from the northeast, these are likely from the Taurid meteor shower. The Taurids are sparse; the occasional fireball makes up for the low meteor count. The Taurids last from mid-October to mid-November.

By Midnight, Jupiter is moderately high in the East; it is the brightest object in Gemini. For telescope observers, Jupiter’s Great Red Spot, a giant storm, is visible at 1:28 AM, Tuesday. Also on Tuesday, at 22 minutes past Midnight, 
the moon Io reappears from behind Jupiter; at 9:55 PM, the ice covered moon Europa begins to cross Jupiter’s face.

Mars rises after 1 AM, and, by Dawn is high enough for observation. But Mars and Jupiter are not the only Solar System members visible. Four comets are detectable in the pre-sunrise hours. Comet ISON is about three degrees from Beta Virginis on Tuesday morning and half that on Wednesday. ISON is about 10th magnitude. Comet Lovejoy brightened by 250 times to reach eight magnitude; it lies about four degrees from the Beehive star cluster in Cancer. Comet Encke, also eighth magnitude, is about six-and-a-half degrees from Porrima in Virgo. Finally, Comet Linear, also eighth magnitude, lies about seven degrees from Arcturus, in Bootes. Comets ISON, Lovejoy, Encke and Linear are observable in medium sized telescopes. Some, however, are low and may require a clear eastern horizon. 

This is Dudley Observatory's Skywatch Line for Friday, November 1, through Sunday, November 3, 2013, written by Alan French.

A thin crescent Moon graces the morning sky before dawn, so the evening sky is dark and moonless, making this weekend a perfect time for stargazing.

Weather permitting; the Albany Area Amateur Astronomers will hold public star party at Landis Arboretum in Esperance at 8:00 pm on Friday and Saturday, November 1 and 2. A variety of telescopes will be set up by club members to provide guests with views of star clusters, nebulae, galaxies, double stars, and other celestial sights. Star parties are open to all and there is no admission fee. There will be a short introductory program in front of the meeting house. For those interested, there will also be a tour of the fall constellations.

Star parties last at least an hour and usually go much longer if the skies are clear. You are welcome to stay as long or as briefly as you like. Be sure to dress warmly. It feels 20 to 30 degrees colder when you are standing under clear night skies. Having extra warm clothing on hand is better than being uncomfortable.

For directions to Landis Arboretum see this link. The star party will be canceled if the skies are mostly cloudy. If in doubt, call 374-8460.

This weekend we set our clocks back to return to standard time. So don’t forget to turn your clocks back an hour before bed on Saturday night, and enjoy your extra hour!

If the skies are clear, and you have a good view to the east southeast, you have chance to spot a partial solar eclipse as the Sun rises on Sunday morning. From Albany, the Sun rises at 6:32 am EST and maximum eclipse is at 6:33 am EST. By 6:50 the Sun will be just over two degrees above the horizon and the Moon’s bite out of the Sun should be easy to spot using a safe solar filter. The eclipse ends at 7:12 am. (The times will not differ much for people in the rest of the Capital District region.)

Make sure you are set to safely observe the Sun! Your retina does not feel pain and it does not heal, so read the information below and check the Sky & Telescope link about safe solar viewing. If in doubt, enjoy the eclipse online at the SLOOH website. You’ll be able to see more of the eclipse there too, but coverage will start earlier.

The easiest way to safely observe the Sun is through a shade #14 welders glass or a pair of eclipse glasses, which some of you may have from a previous eclipse. A shade #14 welders glass is available at many welding supply shops, but call ahead – some don’t carry this darker glass. The 2 inch by 4-1/4 inch plate is inexpensive and can easily be held in front of both eyes to safely observe the Sun. (The welders glass is not safe for use with a telescope.)

Sky & Telescope has more information on the eclipse here. Be sure you also read their article about viewing the Sun safely.

This is Dudley Observatory’s Skywatch Line for Friday, October 25, through Sunday, October 27, written by Alan French.

The Moon is moving toward last quarter, which it will reach at 7:41 pm Saturday. A slightly gibbous Moon rises at 11:18 Friday evening, and a slightly crescent Moon on Saturday at 12:15 am. By Monday morning’s moonrise at 1:13 am the crescent phase should be obvious. The early evening hours this weekend will be dark and moonless, making them ideal for star gazing.

By 8:00 pm the last hints of evening twilight will be gone and the sky completely dark. If you are away from city lights and the effects of light pollution, the Milky Way will be visible as a hazy band of light stretching from the southwest horizon, passing overhead, and then headed down toward the northeastern horizon. The Milky Way is most obvious in the southern half of the sky, and it has quite a bit of structure.

Look high overhead for the star pattern of Cygnus, the Swan. Bright Deneb marks the Swan’s tail, and his long neck stretches south southwestward. Pairs of stars to either side of the star just south of Deneb mark the outstretched wings. The double star Albireo, a pretty and colorful sight at low power in any telescope, marks his head. Part of Cygnus is known to many as the Northern Cross.

Note how the Milky Way is divided into two bands of light starting in Cygnus and going toward the south. The darkness dividing it is known as the Great Rift. It is a series of molecular dust clouds between us and the Sagittarius arm of the Milky Way, blocking the light of the stars beyond.

The hazy band of light we call the Milky Way is simply the combined light of many distant stars as we look along the plane of our galaxy. Binoculars and a lawn chair are great tools for exploring the beauty of the Milky Way, showing hordes of stars and groups of stars invisible to the unaided eye.

Venus continues to dominate the southwestern sky just after sunset, appearing just eight degrees above the horizon at 7:00 pm. Our sister planet, similar in size to Earth, sets just after 8:00 pm. Like the Moon, planets closer to the Sun than our planet show phases. Through a telescope Venus now appears slightly more than half full. In its trip around the Sun it is now catching up with Earth, and will move lower in the evening sky in November and December. It will also grow larger and move toward a thin crescent.

Early risers will find bright Jupiter high in the southeast. Any modest astronomical telescope or spotting scope will show its four brightest moons, appearing as stars to either side of the planet.

The Dudley Observatory Skywatch Line for Wednesday, October 23rd and Thursday, October 24th written by Louis Suarato

Astronomer Ernest Julius Öpik was born in Estonia on October 23, 1893. Öpik was best known for his studies of the solar system’s minor bodies, meteors, asteroids and comets. Öpik correctly predicted comets originated from a cloud beyond Pluto, now known as the Oort Cloud. Öpik was also the first to determine the Andromeda nebula’s distance from Earth. During an expedition in Arizona with Harlow Shapely, Öpik detected approximately 22,000 meteors. Astrologers will tell you that the Sun enters the astrological sign Scorpio on October 23rd. Astronomers will correctly inform you the Sun is still in Virgo. The reason Astrologers are misinformed, and misinforming, is due to the gradual change in the Earth’s rotational axis, known as precession. This slow movement of the Earth, like the wobble of a top, takes place over a 26,000 year period. The Sun may have been in front of the background stars of Scorpio at this time years ago, but it isn’t now. So, think twice if you think you are a “Scorpio”, and how that may affect your life. On Wednesday, the 80% illuminated, waning gibbous Moon sets at 11:36 a.m. EDT. Venus appears approximately 15 degrees above the southwest horizon after sunset. Venus shines at magnitude -4.2 and a telescopic view will show the planet 54% illuminated. A bright International Space Station pass will occur over our region at 7:49 p.m. Wednesday evening. Look for the ISS emerging from the west-northwest horizon and sail under the Big Dipper before fading into Earth’s shadow before reaching Polaris. With the constellations Cassiopeia and Perseus high in the northeast, the Double Cluster, or Caldwell 14, is a wonderful binocular or small telescope target. The Double Cluster consists of open clusters NGC 869 and NGC 884. Each cluster has about 300 blue-white super giant stars. The estimated age of the stars is 12.8 million years old, compared with the stars of the Pleiades star cluster at 75 to 150 million years of age. Look for the Double Cluster between Cassiopeia and Perseus, but closest to the shallower “V” within Cassiopeia. Moonrise occurs in the constellation Orion at 10:19 p.m. followed by Jupiter in Gemini at10:40 p.m. EDT. Mars rises at 2:30 a.m. Thursday morning. Comet ISON will be about 2 degrees to the lower left of Mars. The latest images from the Hubble Space Telescope indicate the comet is still intact. On Friday, October 25th, the Albany Area Amateur Astronomers will be hosting a public Star Watch at the Deerfield Pavilion in Grafton Lake State Park. Directions to the park can be found at http://www.dudleyobservatory.org/AAAA/Directions.html.

The Dudley Observatory Skywatch Line for Wednesday, October 16th and Thursday, October 17th written by Louis Suarato

On October 16, 1982, Halley’s Comet was observed and recorded for the 30th time. Astronomers using the 200-inch Hale Telescope at the Mount Palomar Observatory located the comet beyond the orbit of Saturn, about 11 astronomical Units (AU) from the Sun. Halley’s Comet is a short-period comet and is visible from Earth every 76 years and will appear again in mid-2061. The latest data on Comet ISON indicates it will survive its close encounter with the Sun on November 28th and provide us with naked eye views in December. On Wednesday, the 95% illuminated, waxing gibbous Moon rises in the constellation Pisces around 5 p.m. EDT. As the sky darkens, Venus will appear over the southwestern horizon. Scorpius’ red supergiant star, Antares, will be approximately 2 degrees below Venus. Between Venus and Antares is 22 Scorpii, a blue star 413 light years away and shining at magnitude 4.79. Saturn and Mercury will be lower on the west-southwestern horizon. Jupiter rises a few minutes after 11 p.m. in the constellation Gemini, flanked by Castor and Pollux to the north and Orion’s brightest stars, Betelgeuse and Rigel to the east. Mars rises around 2:30 a.m. in the constellation Leo and will be about 2 degrees below Leo’s brightest star, Regulus. Comet ISON can be found one degree to the north of Mars. On Thursday evening, Uranus will be 3.3 degrees north of the nearly Full Moon. Celebrate the Full Hunter’s Moon Friday night with the Dudley Observatory and Albany Area Amateur Astronomers. We will host a talk and telescope observing at the Octagonal Barn in Knox. Click here for directions.

This is Dudley Observatory’s Skywatch Line for Friday, October 4, through Sunday, October 6, 2013 written by Alan French.

The Moon is new at 8:35 pm on Friday so the weekend skies will be dark and moonless – perfect for enjoying the beauty of the star strewn sky.

Landis Arboretum in Esperance is away from the lights of our larger cities, and the open field near the meeting house provides a fine view of the sky. It makes a superb setting for public star parties held by the Albany Area Amateur Astronomers, and the club will host observing at 8 pm on Friday and Saturday nights, October 4 and 5. These events are free and open to all ages. Star parties are canceled if the skies are mostly cloudy. (If in doubt, call 37-8460.)

At a star party club members set up a variety of telescopes to provide guests with views of various celestial sights, including star clusters, nebulae, double stars, and galaxies. There will also be a brief introductory program near the meeting house at 8:20 followed by a short constellation tour for those interested. There is no set ending time for star parties, and club members often stay quite late if the skies are clear. You’re welcome for a short visit or a long one.

You don’t need anything special to attend a star party, but it is very important to dress warmly. People are used to being out in the cold when they are active. When you are standing under the clear night sky it feels 20 to 30 degrees colder, and having extra warm clothing along is far better than being cold and uncomfortable. A warm hat is essential.

Directions to Landis are at http://dudleyobservatory.org/AAAA/Directions.html.

A young Moon will return to the early evening sky on Sunday, but you’ll need an excellent, unobstructed view to the west southwest to spot it. Look just above the west southwestern horizon at 7:00 pm. The slender crescent Moon will be just three degrees above the horizon. (For reference, if you hold your pinkie at arm’s length, it spans one degree at its tip.) Mercury will be just to the lower left of the Moon, two degrees away and two degrees above the horizon.

The Moon will be higher and not far from brilliant Venus on Monday and Tuesday nights.

The Dudley Observatory Skywatch Line for Wednesday, October 2nd and Thursday, October 3rd, 2013 written by Louis Suarato


On October 2, 1608, Johannes Lippershey demonstrated the first refracting telescope. An apprentice of Lippershey had discovered that, by separating a long focal-lens and a short focal-lens in front of the eye, distant objects were magnified. Galileo replicated this product to study the cosmos, and at a banquet on April 14, 1611 honoring him, a guest called the new optical instrument a “telescope.” On Wednesday, the 5% illuminated, waning crescent Moon sets at 5:11 p.m. EDT. After sunset, look to the west-southwest for Mercury low on the horizon. Saturn can be found approximately 6 degrees above Mercury and bright Venus, now shining at magnitude -3.77, will be about 15 degrees south of Saturn. Venus sets a few minutes after 8 p.m. EDT. As Venus is setting, you will notice a bright star 15 degrees above the western horizon. That star is Arcturus, the brightest star in the constellation Bootes. At magnitude -0.04, Arcturus is the fourth brightest star in the night sky and the brightest star north of the celestial equator. At a distance of about 37 light years, Arcturus is one our Sun’s nearest neighbors. Its diameter is 25 times that of the Sun and its luminosity approximately 115 times greater. Acturus is moving towards the constellation Virgo at the speed of 90 miles per second and is almost at its closest approach to our Sun. In about 4,000 years, Arcturus will be a hundredth of a light year closer to Earth than it is today. Using the proper coordinates, Arcturus can be seen in the daytime sky with a telescope, as it was by astronomer Jean-Bastiste Morin for the first time in 1635. Jupiter rises just before midnight on Wednesday. The shadow of Jupiter’s moon, Ganymede, the largest moon in the solar system, can be seen transiting the planet until 1:30 a.m. At 5.26 a.m., there will only be one Galilean moon visible. Callisto, will be far off to one side of the planet. Ganymede and Io will be transiting, and Io’s shadow will be above Ganymede. Europa will be hidden behind Jupiter. Mars rises around 2:45 a.m. Thursday. Comet ISON can be located approximately 2 degrees to the upper left of Mars. Uranus reaches opposition at 10 a.m. EDT, and reaches its 2013 peak magnitude of 5.7. Look for Uranus rising in the constellation Pisces in the east after sunset. Uranus will appear as a bluish “star” 5 degrees south of Epsilon Piscium. On Thursday evening at 7 p.m., Venus will reach aphelion, its furthest distance from the Sun at .7282 Astronomical units, about 67.7 million miles away. The Zodiacal Light may be visible from October 3rd through the 16th in dark sky locations. Look for a tall, broad pyramid of light tilting right above the eastern horizon with Jupiter at its apex, 80 minutes to 2 hours before sunrise. Celebrate the New Moon by joining the Albany Area Amateur Astronomers for Star Parties this Friday and Saturday nights at the Landis Arboretum in Esperance, NY. Directions can be found at http://www.dudleyobservatory.org/AAAA/Directions.html.

The Dudley Observatory Skywatch Line for Wednesday, September 18th and Thursday September 19th, 2013 written by Louis Suarato

Wednesday’s moonrise occurs approximately 40 minutes prior to sunset. The Full Moon occurs at 7:13 a.m. Thursday morning when it is exactly opposite the Sun. Traditionally, the Full Moon occurring nearest the Autumnal Equinox is known as the Harvest Moon. During most of the year, moonrise occurs 50 minutes later each day, but during the time of the Harvest Moon, moonrise occurs 30 minutes later each night when the Moon’s path along the ecliptic is at its most acute angle to the horizon. At twilight on Wednesday evening, look to the west-southwestern horizon to see Venus passing 3.5 degrees below Saturn. Saturn will be to Venus’ upper right. This will be the closest the two planets will appear in our sky until January 9, 2016, when the two planets will be separated by less than 1 degree in the morning sky. A telescopic view of Venus will reveal a 67% illuminated, gibbous phase. Venus shines at magnitude -4.0 and will brighten to magnitude -4.5 by the end of the year as the planet’s distance from Earth decreases from .97 astronomical units to .32 astronomical units, or approximately 60.5 million miles. The pair will set one hour and 46 minutes after sunset. Jupiter rises in the constellation Gemini a half hour past midnight followed by Mars at 2:55 a.m. in Cancer. Comet ISON can be located about 2 degrees left of Mars. On Thursday morning, there will be a bright International Space Station pass at 4:41 a.m. over our region. The ISS will appear left of Polaris and travel northeast below the Big Dipper for approximately two and a half minutes before reaching the horizon. The Albany Area Amateur Astronomers will be providing solar views on Saturday, September 21st at the Five Rivers Environmental Education Center’s Fall Festival beginning at noon. Joining club members will be Barlow Bob, a solar observing specialist who will be providing his expertise and a wide variety of safe solar observing instruments. We hope to see you there!

This is Dudley Observatory’s Skywatch Line for Friday, September 13, through Monday morning, September 16, 2013 written by Alan French.

 

The Moon was at first quarter Thursday, so a waxing gibbous Moon will dominate the early night sky over the weekend. Moonset is at 12:57 am Saturday morning, 2:06 am Sunday, and 3:17 am Monday. The next Full Moon is on the morning of September 19.

This weekend we have two nice chances to see Tiangong 1, the Chinese space station, passing over the Capital District region. At first magnitude, it should be easy to spot gliding across the sky. On Friday night the station will pass directly overhead. It will first appear just after 7:51 pm in the western sky, and will be overhead seconds after 7:54. It will move into the Earth’s shadow and fade from view at 7:56:26 in the east. On its way up from the western horizon Tiangong will pass by bright Arcturus, the brightest star in Bootes, the Herdsman, and just at its reaches overhead it will pass close to bright Vega.

Saturday’s appearance of Tiangong will be later and the skies will be darker. It will appear rising up from the western sky at 8:15 pm, will be highest just before 8:18 when 61 degrees above the south southwestern horizon, and will vanish as it moves into the Earth’s shadow at 8:19 when 31 degrees above the southeastern horizon. Its path will again take it past Arcturus, and it will pass very close the Altair, the luminary of Aquila, the Eagle. There is no one aboard the Chinese space station now, but there are six crew members on the International Space Station, which now passes over our area in the morning sky. Early risers on Monday morning will have a fine view of the ISS as it passes high in the sky. When high in the sky, it will shine at magnitude -3.4, almost as bright as Venus appears in the early evening sky, and should be very easy to spot. The ISS will move out of the Earth’s shadow and come into view at 5:28:46 when 24 degrees above the west southwestern horizon. It will be highest at 5:30:36 when 83 degrees above the north northwestern horizon – essentially overhead – and will vanish at 5:34 in the northeast. It will pass through Aries just after moving out of the Earth’s shadow, and will pass through Perseus just before reaching its highest point.

We can see many satellites cruise across the sky during the hours just after sunset and just before dawn, when we are in the Earth’s shadow and they are still up in sunlight. On Friday night, for example, 24 satellites shining at magnitude 3.5 or brighter will be visible from here. Including satellites down to 5th magnitude, the number increases to 165.

 

The Dudley Observatory Skywatch Line for Wednesday, August 14th and Thursday, August 15th, 2013 written by Louis Suarato


The Moon reaches its First Quarter phase at 6:56 a.m. EDT on Wednesday and rises at 2:08 p.m. local time. The First Quarter phase is generally considered the best time to observe the Moon. It is during this phase when shadows provide detail of the features along the terminator, the dividing line between the illuminated and dark side of the Moon. Sunset occurs around 8 o’clock. At that time, Venus will begin to appear approximately 14 degrees above the west-southwestern horizon. Venus is shining at magnitude -3.8 and a telescopic view will reveal a waning gibbous phase. Venus will set at 9:25. Look for Saturn in the constellation Virgo, 23 degrees above the southwestern horizon, between Venus and the First Quarter Moon. Look left of the Moon for the constellation Scorpius low on the horizon, with its bright reddish star, Antares. Antares, or Alpha Scorpii, is the fifteenth brightest star in the night sky shining at magnitude 1.05, and is approximately 550 light years from Earth. This red supergiant star has a radius 850 times that of our Sun. Antares, meaning “anti-Mars” because of its similarity in color, is one of four 1st magnitude stars within 5 degrees of the ecliptic. The other 1st magnitude stars are Spica, Regulus and Aldebaran. Because of their proximity to the ecliptic, these stars are occasionally occulted by the Moon. The next lunar occultation of Antares won’t occur until 8/25/2023, but on October 5th of this year, Spica will be occulted by the two-day old crescent Moon. This occultation will be visible over North America. The Moon sets at 6 minutes past midnight. Jupiter rises at 2:32 a.m. followed by Mars about 40 minutes later, both within the constellation Gemini. On Thursday, August 15th, at 7:30 p.m., the Albany Area Amateur Astronomers will be having their monthly meeting at the Landis Arboretum in Esperance, NY. The meeting will be followed by a public Star Party. On Friday, The Albany Area Amateur Astronomers welcome you to join them at a public Star Party at Cherry Plain State Park. Directions to the park can be found at http://www.dudleyobservatory.org/AAAA/Directions.html.

The Dudley Observatory Skywatch Line for Wednesday, July 31st and Thursday, August 1st, 2013 written by Louis Suarato


On July 31, 1971, astronaut Dave Scott became the first person to drive a vehicle on the Moon when he took the Lunar Rover out for a spin in the Hadley-Apennine region. The Lunar Rover traveled 17.4 miles and carried 168 pounds of lunar rocks. On Wednesday, the 30% illuminated, waning crescent Moon sets at 3:30 p.m. EDT. Venus appears over the western horizon after sunset and sets at 9:45 p.m. EDT. Saturn will reveal itself approximately 30 degrees over the southwestern horizon after sunset and sets around midnight. After midnight, look above the southwestern horizon, toward the constellation Aquarius, for meteors emanating from the radiant of the Delta Aquariid meteor shower. The radiant can be found above the sole bright star, Fomalhaut, in the southwest. With the Moon absent from the night sky, expect to see approximately 10 meteors per hour away from city lights during this minor shower. Take advantage of the dark skies to observe the globular cluster, M2, in Aquarius. M2 shines at magnitude 6.5 and is about 50,000 light years from Earth. This globular cluster contains over 100,000 stars and spans 150 light-years. M2 can be located 5 degrees north of the star Beta Aquarii.

 

Dudley Observatory Skywatch Line for the days of Friday, July 19th, through Monday morning, July 22nd, 2013, written by Tony Scalise.

Friday, July 19th, marks the 200th day of the year.  There are 165 days left in the year.  The Sun rises at 5:34 and sets at 8:30.
The Moon is at gibbous phase, 3 to 1 days before full and rising in the southeast after sundown.  Times of moonrise are 5:29 for Friday evening, 6:29 for Saturday evening, and 7:23 for Sunday evening.  The Moon is at perigee on Sunday afternoon and becomes full on Monday afternoon.
 
Saturday, July 20th, marks yet another anniversary, the 44th to be precise, of the first humans to walk on the Moon with the landing of Apollo 11.  The same day also marks the 37th anniversary of the landing of Viking 1 on Mars, the first spacecraft to successfully do so.

This weekend will cap the week with a number of close conjunctions between the planets and the stars and two wonderful photo-shoots of Earth from deep space.
Venus, at magnitude -3.9, will be setting in the west after sundown.  On Sunday it will be 1.2 degrees above the star Regulus.  Venus sets about 10:00 in the evening.
 
On Monday morning, one hour before sunrise, Mars, at magnitude 1.6, will be 8/10ths of a degree to the north of Jupiter, which shines at magnitude -1.9.  Look to the east-northeast for the two planets rising low above the horizon.  The nearly full Moon will be behind you setting in the west.

Saturn will be found in the southwest as the Sun sinks below the horizon.  Though it is low in the sky after dusk, you can still catch a breathtaking view of the magnificent planet and its rings.  Saturn sets just after midnight.

The big news for Saturn this weekend is that NASA's photo-shoot of Earth and Saturn is still on.  On early Friday evening, NASA's Cassini spacecraft that is currently orbiting Saturn will take a series of photographs of Saturn and its rings beautifully backlit by the Sun, similar to the photo taken by Cassini in 2006.  This time though, a high resolution camera will be used so that Earth will be in the composite photo as a blue and white speck just outside the rings.  The 15 minute exposure will take place from 5:27 to 5:42 Eastern Daylight Time in the evening.  Only the continents North and South America will be facing Saturn at the time of the exposure.  North America during this time, though, will still be in broad daylight, so Saturn will not be visible to the naked eye, although it is there high in the east at that time.  From South America, which will bask in the early evening darkness, Saturn will be prominently visible.  This is history in the making folks, as this is the first time ever that the planet Earth is being photographed from a planetary spacecraft with we Earthlings having been given advanced notice. NASA is asking the fellow citizens of these two continents to face the ringed planet during the photo-shoot and to wave.  NASA is also asking to have pictures taken of yourselves waving and shared with others through the Internet.  Of course, you may dress in your Sunday best if you wish, but don't jump up and down while you are waving lest the image of Earth should appear as a blur in the photograph.  Go to http://saturn.jpl.nasa.gov/news/waveatsaturn/ for more details and also on information on obtaining a certificate that you participated in the Wave-at-Saturn campaign.

But that's not all, folks.  NASA's MESSENGER spacecraft, orbiting the planet Mercury, is searching for natural satellites of the innermost planet with its own high resolution camera and in doing so, will also be taking photographs of the Earth in the background.  The targeted dates and times for these photos are July 19th and 20th at 7:49, 8:38, and 9:41 Eastern Daylight Time in the morning for both dates.  On both of these dates, Europe, the Middle East, and Central Asia will be facing MESSENGER and Mercury.  Mercury is currently too close to the Sun to be seen.

The Dudley Observatory Skywatch Line for Wednesday, July 17th and Thursday, July 18th written by Louis Suarato

July 17th is the anniversary of the first photograph taken of a star other than the Sun. In 1850, William Bond and John Adams Whipple imaged the star Vega from Harvard University’s 15 inch refractor using the daguerreotype process. Vega, or Alpha Lyrae, is the brightest star in the constellation Lyra, and the fifth brightest star in the night sky. Vega, along with Deneb and Altair, form the Summer Triangle. Vega, about a tenth the age of our Sun, is 25 light-years from Earth and shines at a magnitude of +0.03. Vega completes a rotation once every 12.5 hours, a speed that creates temperatures at its poles thousands of degrees hotter that those at its equator. Earlier this year, scientists announced the discovery of an asteroid belt circling Vega. This discovery has led scientists to believe there also may be a planetary system surrounding the star. Look for Vega almost directly overhead as the sky darkens. After sunset, Venus and Regulus are about 6 degrees apart over the western horizon. Above and to the south, the 70% illuminated, waxing gibbous Moon, shares the sky with 0.80 magnitude Saturn, and 0.95 magnitude Spica. The planet Uranus rises around midnight in the constellation Pisces, just 4 hours after it is stationary. Uranus will begin its retrograde or westward motion against the stars until December 18th, when the Earth once again moves away from the outer planet. Thursday morning’s eastern sky features the planets Jupiter and Mars, which rise less than 2 degrees apart at approximately 4:30 EDT in the constellation Gemini. The International Space Station returns to our skies this week. On Friday morning at 4:21, look to the southwest horizon to see the ISS appear in the constellation Capricornus, sail past Uranus in Pisces, fly over the Pleiades in Taurus and pass Mars and Jupiter as they rise on the northeastern horizon. Check www.heavens-above.com for the exact times for your location.

Skywatch Line for Monday and Tuesday, July 15th and 16th. By Joe Slomka

The Sun sets at 8:31 PM; night falls at 10:39. Dawn breaks at 3:24 AM and ends with sunrise at 5:31.

  The First Quarter Moon is the first object visible in tonight’s sky. It rose about 1 PM and sets after Midnight. The Moon shares Virgo with Saturn. Monday night sees the Moon near the star Spica; Tuesday evening finds it cuddling up to Saturn. 

Saturn, despite the Moon’s brilliance, is always a treat. The planet just passed “Quadrature,” which means it is ninety degrees from the Sun. The giant planet casts it shadow on the famous rings, a sight visible in amateur telescopes under moderate power.

  Venus, second only to the Moon in brightness, lies low in the West. Observers should work quickly to see it, before our murky atmosphere blurs the view. Venus sets about 11 PM.

  Midnight witnesses the appearance of Neptune, in Aquarius, and Uranus, in Pisces. The giant outer planets travel imperceptibly through these constellations and seem to remain fixed in their positions. Finder charts are available in astronomy magazines, websites and apps. 

Mars and Jupiter join Neptune and Uranus in the early morning. Mars rises about 3:35 AM, with Jupiter following fifteen minutes later. Both are moderately high in the East. Tuesday morning finds Mars close to the star cluster M35; Wednesday finds it slightly nearer to Jupiter.

  As appropriate for the upcoming racing season, two horses appear by midnight. The largest horse is, of course, Pegasus. The smallest is Equuleus. This dim constellation is easy to find. Pegasus flies upside down and is easily identified as a Great Square. Two thin chains sweep northward from the upper left. If one sweeps across the chains, binoculars reveal a large hazy oval; this is revealed, in telescopes, to be the Andromeda Galaxy – about two and a half million light years distant, accompanied by two smaller satellite galaxies. You can see it with the naked eye under rural skies. Pegasus’ neck flows from the lower right corner and angles up. Equuleus is the small angular line of stars West of the Pegasus’ nose. A globular star cluster, M 15, lies exactly halfway between Pegasus’ nose and Equuleus. This too is easily seen in binoculars.        

Clear Skies 
Joe Slomka

Dudley Observatory Skywatch Line for the days of Friday, July 12th, through Monday morning, July 15th, 2013, written by Tony Scalise.

Friday, July 12th, marks the 193rd day of the year.  There are 172 days left in the year.  The Sun rises at 5:28 and sets at 8:34.

The Moon is a waxing crescent, 4 to 6 days after new, and found setting over the western horizon after sundown.  Times of moonset are 10:35 for Friday evening, 11:04 for Saturday evening, and 11:33 for Sunday evening.  The Moon turns first quarter on Monday afternoon.

Venus is also found after sunset above the west-northwestern horizon and to the right of the Moon.  Shining very brightly at magnitude -3.9, Venus sets about 10:00  in the evening.  Although the elongation of Venus from the Sun is increasing each week, its orbit currently lies at a shallow angle with respect to the horizon and thus for its current evening apparition, Venus does not set that much later nor does it get all that much higher as each week passes.

Saturn, at magnitude 0.5 and long past opposition, is found at its highest above the south-southwestern horizon after sundown.  Saturn gets lower in the sky as the evening progresses and sets about 1:00 in the morning.

About one hour before sunrise, look for Jupiter and Mars rising together above the east-northeastern horizon.  Ruddy Mars at magnitude 1.6 rises 25 minutes before bright Jupiter does at magnitude -1.9.  Jupiter and Mars are currently at about 4 degrees away from each other and are closing in for a conjunction next week when they will be less than a degree apart.

On Sunday July 14th, in 1965, history was made when the Mariner 4 spacecraft took the first ever close-up photos of a planet.  Launched from Cape Kennedy eight months earlier, Mariner 4 performed a simple flyby of the planet Mars at 10,000 km away from the surface.  The spacecraft was equipped with four solar panels at right angles to each other, a star tracker that was set to the star Canopus to properly align the spacecraft, and a television camera that sent back digital images of the Red Planet.  During its quick flyby, Mariner 4 took 22 images of the surface of Mars, or 11 pairs of mosaic photos.  The resolution was very poor by today’s standards, although of good quality for its day.  Yet when scientists, and the public, got humanity’s first close-up views of Mars, they saw a landscape not much different than that of the Moon.  Craters, craters, and more craters.  Photo number 11, depicting a very large impact crater 120 km across, was the most famous photo taken of the 22 and was published in many then current astronomy textbooks.

But unknown to the scientists at the time, and by sheer happenstance, the spacecraft’s camera took photos of a region of Mars that happened to be more highly cratered than the rest of Mars. The camera missed the huge, deep valleys, the vast plains, and the sky high volcanoes.  Those 22 photos covered only 1% of the total surface area of Mars. Still, however, they dashed the hopes of many who were looking for a landscape more conducive to life.  Gone were the canals of Percival Lowell. Gone, too, were the simple vegetation that many scientists were convinced was growing on Mars.  Mars was a dead planet.  But in spite of that view, over the next five decades more spacecraft would be sent to our sister planet and the debate over life on Mars would become even more unsettled than ever before.

Photo number 11, by the way, was presented by the Mariner 4 project manager of the Jet Propulsion Laboratory to President Lyndon Baines Johnson.  From JPL to LBJ.

Dudley Observatory Skywatch Line for Wednesday, July 10th and Thursday, July 11th written by Louis Suarato

American Astronomer, Alvan Graham Clark, was born on July 10, 1832. Clark, along with his father and brother as ‘Alvan Clark & Sons’, became the famous refracting telescope lens makers for the United States and Europe. In 1861, Clark observed Sirius’ companion star, Sirius B, and went on to discover a total of fourteen double stars. After his father and brother died, Alvan made the 40 inch lens for the Yerkes Observatory Telescope, which is the largest operating refracting telescope in the world. On Wednesday, the 7% illuminated, waxing crescent Moon sets at approximately 9:30 p.m. EDT. Before setting, the Moon will be 6.3 degrees south-southwest of the Beehive Cluster (M44), and 6.7 degrees south-southwest of Venus. The bright star, Regulus, will be joining the crescent Moon and Venus on Thursday when it will appear 5.3 degrees north-northwest of the Moon. Saturn can be found a little more than halfway up in the southwest, in the constellation Virgo, as the sky darkens. A telescopic view of the ringed planet will reveal its largest moon, Titan, and Tethys on one side and Mimas, Dione, Enceladus, and Rhea extending out to the other side. Sunrise occurs at 5:30 on Thursday. On Thursday morning, about 50 minutes before sunrise, look to the east-northeast to see Mars 5 degrees above Jupiter. On July 11, 1801, the astronomer Jean-Louis Pons discovered his first comet. Charles Messier observed the same comet the next day and shares the discovery. Pons went on to discover or co-discover 37 comets. His first discovery, Comet Pons, was Messier’s last. The much anticipated, Comet ISON was recently photographed by the Hubble Space Telescope. ISON is traveling at 48,000 miles per hour and is 403 million miles from Earth and is crossing between the orbits of Mars and Jupiter. On November 28, ISON will be within 800,000 miles of the Sun’s surface. This close encounter could cause the comet to flare to the point of being naked-eye visible in our December night sky. On Friday, July 12 at 8 PM, Siena assistant Professor of Physics & Astronomy, Dr. John Moustakas, will give a lecture on “Building Blocks of the Universe” as part of Dudley Observatory’s Octagonal Barn Star Party program. The link for directions can be found on the Observatory’s main page http://www.dudleyobservatory.org/.

Skywatch Line for Monday and Tuesday, July eighth and ninth. By Joe Slomka

The Sun sets at 8:35 PM; night falls at 10:47. Dawn breaks at 3:14 AM and ends with sunrise at 5:26.
 After sunset, Venus is the first and brightest object to become visible. It lies low in the West, about eleven degrees above the horizon. Notice Venus’s height and position among the stars. While Venus speeds through various constellations, it remains the same height through October.
  Deeper into twilight, Saturn appears in the Southwest, twelve degrees to the upper left of the slightly dimmer star Spica. Saturn, still near Quadrature, casts its shadow on its rings, a telescopic sight not to be missed. Saturn sets around 1:20 AM.
 The Moon turns “New” on Monday. Tuesday evening sees a very thin crescent Moon about five degrees above the western horizon. Binoculars may help. Wednesday’s sunset will present an easier Moon for observation. Tuesday’s Moon sets after 9 PM; Venus sets an hour later.
 Midnight finds Neptune in Aquarius; Neptune rose at 10:46 PM, and is best observed before Dawn. Uranus occupies its usual spot in Pisces, having risen after Midnight. Astronomy magazines, websites and apps provide finder charts for both planets.
 Both Mars and Jupiter rise during daybreak. Mars rises first and is about nine degrees high at Civil Dawn. Jupiter follows at 4:21 about five-and-half degrees to Mars’ lower left. The brightening sky makes detailed observation difficult; however, both can be spotted through the solar glare through binoculars or telescopes.
 July ninth is an important date for variable star observers. It is the day that Mira, a star in the constellation Cetus is predicted to be at peak brightness. Stars vary their output for many reasons. Mira was the first variable star discovered. Mira is a Red Giant – an old, bloated Sun-like star nearing the end of its life. It is also a double star; a companion white dwarf steals matter off of the main star and onto a Saturn-like ring. Mira pulsates in a 332-day (11 month) cycle. Unlike other variables, Mira does not have fixed maximum and minimum levels. Peak brightness is about magnitude three; minimums can be as low as ninth. In 2007, ultraviolet cameras on NASA’s GALEX spacecraft captured Mira with a long tail. Mira, and its white dwarf, are rocketing across space at 130 kilometers per second, leaving behind a 13 light-year long trail of gas and dust.  
Clear Skies 
Joe Slomka

Dudley Observatory Skywatch Line for the days of Friday, July 5th, through Monday morning, July 8th, 2013, written by Tony Scalise.

Friday, July 5th, marks the 186th day of the year.  There are 179 days left in the year.  More than half the year is now over with.  The Sun rises at 5:23 and sets at 8:37.

On Friday, July 5th, at 10:44 in the morning, the Earth is at aphelion at 152 million Km, the furthest distance form the Sun for the year.  This distance has little to no effect on the climate and weather for the Earth is only 3% farther than it is at perihelion, when it is closest to the Sun in January, although one would like to hope otherwise judging from the sultry weather and the wildfires we have been having.

The Moon is a very thin waning crescent rising over the eastern horizon before dawn.  Times of moonrise are 4:10 for early Saturday morning and 5:01 for early Sunday morning.  The Moon turns new at 3:16 Monday morning.

Venus is the star of the early evening.  About one hour after sunset, look for brilliant Venus setting in the west-northwest.  Venus sets about 10:00 in the evening.

Saturn is still hanging above the southern horizon after sundown.  You have only a few hours to observe it for the ringed planet will set at 1:30 in the morning.

One hour before sunrise you can catch Jupiter rising in the east-northeast with a dimmer, ruddy looking Mars to its upper right and the old Moon to the right.

This weekend, hopefully the soggy weather and cloudy skies will be history, if only briefly.  If so, we have a chance to look into the dark skies above us.  Grab your binoculars or a telescope and a star map for the Milky Way will present its finest views as it arcs high overhead from Cassiopeia the Queen in the north to Cygnus the Swan overhead to Scorpius the Scorpion in the south.

By 11:30, the star Vega in the constellation Lyra the Harp will be at the Zenith, directly overhead.  Shining like a brilliant diamond at magnitude 0, Vega is 25 light years away. It was the first star, other than our Sun, to be photographed with the advent of photography in the 1840s.  In Lyra, also look at the star Epsilon Lyrae.  It's a double-double star - a multiple star system consisting of four stars 160 light years away from Earth.  Look also at Zeta Lyrae.  This is another double star with very contrasting colors - red and blue.  Of course there is the famed Ring Nebula, also called M57, in between Beta and Gamma Lyrae, the remains of a Sun-like star that had shed its outer shell in the form of a spherical nebula near the end of its life span.

Now turn to Cygnus the Swan. It doesn't take much imagination to see that this constellation's pattern of stars resembles a goose with a long neck and short tail along with its outstretched wings.  The head of the Swan is Albireo.  Albireo is another strikingly beautiful double star - one star being orange and the other blue, and both 410 light years away.  The star at the opposite end of the Swan marks the tail of the Swan. It is called Deneb, which is Arabic for the word tail.  While this star doesn't appear to be all that impressive to look at, Deneb, a blue-white supergiant star 2,600 light years away, is one of the most luminous star known.  It is 200 times larger than the Sun and up to 200,000 times more luminous than the Sun.  It is so bright that it produces more energy in the single night you are looking at it than our Sun does in 100 years.  As for the name Deneb, it's interesting to note that other animal constellations with tails, including Capricornus the Sea Goat, Leo the Lion, and Cetus the Whale all have tails named Deneb, or a slight variation of that name.

Speaking of Cetus the Whale, stay up late to look for this constellation. While it rises in the east after midnight, it appears highest over the south-east at 4:00 in the morning and there is no better time than now to observe the star Omicron Ceti, or Mira the wonderful star in the Whale's neck.

Mira is a long period variable red giant star nearly 400 light years away and with a period of 331 days, or about 11 months. Most of the time Mira is not visible to the unaided eye.  But this month it is nearing its peak brightness of magnitude of 3.0 to 2.0, up from its from a faint minimum of about 10.0.  Peak brightness is predicted to occur around July 21 to July 31 before the star begins to drop back towards minimum.

Mira was the first star to be identified as a variable, since at least 1596 by David Fabricius, a German pastor who dabbled in astronomy.  What causes the periodic brightening of Mira?  Mira periodically sheds the outer layer of its atmosphere which in turn causes its brightness to fluctuate.  In doing do, it leaves a trail of plasma material that is grabbed by Mira's faint companion star 70 astronomical units away.  The Hubble Space telescope has photographed the shed material as a long nebulous stream starting at Mira and ending at the dwarf companion.  Hubble photographs also show that Mira is not perfectly spherical but is actually a distorted blob, with a plume like feature pointing towards Mira's companion star.

Look at Mira this weekend, compare it with other, non-variable stars, photograph it if you can, and then look at it again in October about midnight when Cetus the Whale will be at its highest over the south.  This will give you the chance to see how much Mira will fade and then completely disappear until its next maxima in June of next year.
Lastly, join the Albany Area Amateur Astronomers this weekend on the evenings of July 5th and July 6th at 10:00 for two nights of star watching.  The public is invited to attend and the events are held only if the skies are clear.  Go http://nightsky.jpl.nasa.gov/event-view.cfm?Event_ID=44899 for more information or call 374-8460.

 

The Dudley Observatory Skywatch Line for Wednesday, July 3rd and Thursday, July 4th written by Louis Suarato

The 17% illuminated, waning crescent Moon sets around 4:42 p.m. EDT on Wednesday, leaving us with a dark night sky for observing. After sunset, Venus appears over the west-northwest horizon. A challenge will be to spot the Beehive Cluster, M4, in background of Venus. The planet and star cluster will be 5 degrees above the horizon an hour after sunset. To the south, Saturn shines at magnitude 0.6, about 35 degrees above the horizon, in the constellation Virgo. Saturn’s retrograde motion ends July 8th and 9th when it returns to its normal eastward journey. On July 19th, NASA’s Cassini spacecraft, currently orbiting Saturn, will take the third-ever picture of the Earth from the outer solar system. On that day, Cassini will be aligned where Saturn will eclipse the Sun. With the Sun’s light blocked, NASA’s scientist will direct Cassini to look back at Earth and image our planet. The first and most distant image of Earth from deep space was taken by Voyager 1 in 1990 from a distance of 3.7 billion miles away at the request of Carl Sagan. This image is known as “The Pale Blue Dot”. East of Saturn, in the constellation Scorpius, is the bright star Antares. Antares, meaning “anti-Mars”, is a red supergiant star and the sixteenth brightest star in the nighttime sky. Antares is about 550 light years from Earth and has a radius 883 times that of the Sun. Just 1.3 degrees to the right of Antares, is the globular cluster M4. M4 is approximately 7,200 light years away, and along with NGC 6397, is one of the closest globular clusters to our solar system. Images taken by the Hubble Space Telescope in 1995 have helped scientists determine that the white dwarf stars with M4 are the oldest known stars in the Milky Way Galaxy at 13 billion years old. Neptune rises in the constellation Aquarius at 11:10 p.m. and Uranus rises in Pisces one and one half hours later. The pre-dawn sky on Thursday morning features a 14% illuminated crescent Moon in Taurus between the Pleiades and Hyades star clusters. Mars is challenge, rising later at 4 a.m. and Jupiter is still lost in the Sun’s glow. This weekend, on Friday and Saturday nights, the Albany Area Amateur Astronomers invite you to join them for Star Parties at the Landis Arboretum in Esperance, NY. Directions can be found at http://nightsky.jpl.nasa.gov/event-view.cfm?Event_ID=44899 .

Skywatch Line for Monday and Tuesday, July First and Second. By Joe Slomka

The Sun sets at 8:37 PM; night falls at 10:52. Dawn breaks at 3:06 AM and ends with the Sun rising at 5:21.

Venus is the brightest object, low in the early evening sky. Forty-five minutes after sunset, it stands nine degrees above the horizon. Telescopic views show the planet ninety percent illuminated. Venus sets about 10:11.

As the sky darkens, Saturn appears in the Southwest. Saturn seems as a zero magnitude object, twelve degrees to the upper right of slightly dimmer Spica, the brightest star of Virgo. This is a great time to observe Saturn. The planet is at “Quadrature,” which means it is ninety degrees away from the Sun and casts its shadow on the famous rings. Observers can see the shadow through small-to-moderately sized telescopes under medium powers.

Neptune rises in Aquarius at 11:14 PM and is well placed for observation before Dawn. Uranus follows by rising at 12:41 AM in Pisces. Both planets require finder charts from astronomy magazines, websites and apps.

The Moon, past Last Quarter, rises at 1:27 AM Tuesday, and 2 AM Wednesday, occupying Aries both days. The beautiful Pleiades star asterism should be visible. The Moon continues to be observable after sunrise.

Mars rises during Dawn and might be seen low in the East with binocular help.

The dwarf planet Pluto reaches opposition tonight, but most people cannot see it. Pluto is notoriously dim and small; it is 1600 times dimmer than the faintest naked-eye star. It took Clyde Tombaugh years and thousands of photographs before he found it. In addition, it lies low in Sagittarius within the Milky Way, amid thousands of similar looking stars. Observers with large telescopes and very dark skies have a chance to find it. Pluto orbits the Sun every 246 years. Its closest approach was in 1989, which means that Pluto is on its way out to the far reaches of the Solar System. The New Horizons space probe was launched towards Pluto in 2006; it will fly by Pluto in 2015. Pluto’s first moon, Charon, was discovered in 1978; since then, the number of Plutonian satellites swelled to 5, including Nix, Hydra and two unnamed moons. The two newest, discovered after New Horizon’s launch, created some concern for NASA, as it tries to safely pilot the spacecraft through their orbits, and worry about more possibly undiscovered moons.

Clear Skies

Joe Slomka

Dudley Observatory Skywatch Line for the days of Friday, June 28th, through Monday morning, July 1st, 2013, written by Tony Scalise.

Friday, June 28th, marks the 179th day of the year. There are 186 days left in the year. The Sun rises at 5:20 and sets at 8:38.

The Moon is waning towards last quarter, which occurs on Sunday morning at 12:55. Look for the waning Moon rising over the eastern horizon about midnight or thereafter. Times of moonrise are 11:56 for late Friday evening, 12:26 for Sunday morning, and 12:56 for Monday morning.

As we move into the month of July, during the short but dark evenings expect to see the Milky Way arcing nearly high overhead. This month it will be possible to have a good view of the central bulge of the Milky Way, which is rich with dense, colorful nebula and stars and located among the constellations of Sagittarius the Archer and Scorpius the Scorpion.

About an hour after sunset, only the planet Venus will found above the west-northwest horizon. The planet Mercury has sunk back into the solar glare and will soon be in conjunction with the Sun on the 9th. Look for Venus to be to the left of the stars Castor and Pollux of Gemini the Twins. Of course, Saturn, located in the constellation Virgo the Virgin, is still visible, found above the southwest after sundown at 12 degrees to the east of Spica. Saturn sets a bit too early at midnight.

In the early morning twilight, Mars is now visible rising in the east-northeast and located in between the tips of the horns of Taurus the Bull and the Hyades open star cluster. And the giant planet Jupiter is finally reemerging from the solar glare in the morning twilight. You can find it to the lower left of Mars.

And of course, there is a little bit of astronomy history to cap this weekend's Skywatch Line. The United States is not the only country with space telescopes. Although it's own Hubble Space Telescope is certainly the most popular and gets much press for its dramatic and colorful photos of deep space objects, Sunday, June 30th, marks the 10th anniversary of the launch of Canada's own space telescope. Called the MOST, or Microvariability and Oscillations of STars, telescope, this suitcase-sized telescope, at 65 cm wide and tall and 30 cm deep, is also the world's smallest space telescope, tiny compared to the bus-sized Hubble Space Telescope. It also has a 15-cm mirror compared to the Hubble's 2.4-meter mirror. Hence the MOST space telescope was nicknamed the Humble Space Telescope. The purpose of MOST is not to take dramatic photos of the Orion Nebula and other deep sky objects. It's primary mission is to monitor variations in light coming from a star using the science of stellar seismology. Stellar seismology is the study of pulsating stars through the oscillations or propagation of density waves that occur within the interior of the stars, similar to the seismology of the Earth. This is done by monitoring the light intensity of a star over time, or rather the star's light curve. This in turn can give clues to the star's interior. The advantage of MOST is that it can observe a single star for up to 60 days in order to detect any oscillations, whereas with the larger Hubble telescope, such long observing times are simply unavailable due to the competition among many astronomers with different research projects. Shortly after its launch into orbit, MOST determined that the star Procyon, in the constellation of Canis Minor, has no oscillations at all, contrary to earlier scientific measurements. MOST is also capable of detecting exoplanets transiting a star. It discovered a carbon rich, super-Earth size exoplanet, called 55 Cancri e, orbiting a yellow dwarf star, much like our Sun, in the constellation of Cancer the Crab.

Orbiting at 800 km above the Earth, higher than the Hubble telescope, MOST is still going strong at 10 years of age and continues to monitor the variations of light from many stars. To date, it has collected light curves for over 5,000 stars and is currently observing its 226th Primary Target Field. It also continues to collect data on 55 Cancri e, the super-Earth carbon planet, making more accurate measurements of the planet's radius, orbital period, and albedo. For such a humble telescope, MOST has certainly made major contributions to the field of astronomy.