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Skywatch July 2001

July 1 - 8  |   July 9 - 15   |    July 16 - 22   |    July 23 - 29  |    July 30 - 31


 NOTE: Times given in the scripts are all local Schenectady, New York time.

Friday, June 30th to Sunday, July 1st. Written by John Schroer


Monday, July 2nd. Written by Joseph Slomka.

The Sun sets tonight at 8:37, and ends with twilight at 10:52 PM. Dawn breaks at 3:10 AM and ends with sunrise at 5:20. The almost full Moon is already risen, and remains up nearly all night.

Only Mars can be seen in the face of a very bright Moon. The planet is slowly pulling away from Earth, becoming gradually dimmer and smaller. Mars is still good for telescopic observation. Mars is found about six degrees below the Moon and to the left of the bright star Antares.

Just before dawn, three bright planets line up in the northeast. Venus is brightest and highest, just below the beautiful star cluster, the Pleiades. Venus appears about two-thirds illuminated. Saturn appears to Venus' lower left. The Ringed Planet is beginning its appearance, while Mercury brings up the rear, close to the horizon.

After the Moon sets, look to the Southeast. Comet Linear should be lurking above the horizon. Reports are that it is a splendid binocular object, although hills and trees may hide this visitor to our Solar System.

This is the anniversary of some truly spectacular cosmic fireworks. On July 4, 1054, a star exploded, shone brightly in daytime, and disappeared after about a year. The Crab Nebula is all that is left, a cloud of gas and debris, expanding at 600 miles per second, with a diameter of 6 light years and 6300 light years distant. Recent studies revealed that the remnant star is a pulsar, a very dense star that does not emit light, but radiation in regular bursts, hence the name. This radiation lights up the neighboring gas in infrared light. This is the most conspicuous supernova remnant. Astronomers now study such objects in all wavelengths: radio, optical, infrared and X-rays. The results are that the products of these gigantic events are actually neutron stars, spinning very rapidly. Theoreticians now have two possible models, both say that neutron stars are made of "strange matter." The nature of this "strange matter" is still open to question.



Tuesday, July 3rd. Written by Jonathan Cassidy.

The Moon is near full so most of the stars of the sky will not be visible. The full Moon happens nearly every month, but not quite at the same time.

When the Moon is full, as it is this week, it is best to look in the sky for other bright objects to observe. Mars has been the brightest object other than the Moon lately. It is still magnificent and through a telescope a definite disk as opposed to the stars which are points of light.

To the East of Mars is the densest part of the Milky Way glx. The Moon will cruise through the constellation Sagittarius. See if you can make out in this constellation the Centaur for which it is named or the Tea Pot asterism. Most people see the Tea Pot with ease but finding the half man half horse with a bow and arrow is difficult.

The Moon at times passes in front of other bright astronomical bodies. During this pass of Sagittarius the Moon will come close to or pass in front of many stars some will be bright enough to see disappear behind the Moon. This is called occultation and is a delight to see.



Wednesday, July 4th. Written by Ray Bogucki.

Today the Earth passes through aphelion, the farthest point in its orbit from the Sun, at 94.5 million miles. In early January, it will be at perihelion, its closest approach to the Sun and 3 million miles closer than tonight. The fact that the Earth is farthest from the Sun in summer and closest in winter provides a slight moderation in the extremes of the summer and winter temperatures in the northern hemisphere. The reverse is true in the southern hemisphere which is now in the depths of winter.

Mars continues to dominate the evening sky, shining at a magnitude of minus 2.2 with a diameter of 20 arc-seconds. Clear views of surface markings on the red planet continue to be elusive since it never gets very far above the horizon where the Earth's atmosphere tends to be turbulent. The other four bright planets have abandoned the evening sky and are now gathering in the early morning sky where they will present some close conjunctions during July.

Venus leads the parade, rising about 3 a.m. in the constellation Taurus. Saturn follows about a half-hour later. Saturn is not far from Aldebaran, the red eye of the Bull, lying on the opposite side of the V-shaped Hyades star cluster that forms the face of the Bull. This happy coincidence provides Taurus with two bright eyes during July. Mercury and Jupiter rise close together about an hour before sunrise. The distance between this pair will close each day for the next week until they stand less than 2 degrees apart -- about one-thumb width at arm's length. Two days later, Venus and Saturn will approach to less than one degree apart. In mid-July the four planets will form a nearly straight line with a span of 27 degrees. In a spectacular maneuver, the waning crescent Moon will move down the line over a two-day period, occulting all four planets in a row. The only occultation visible from this area will occur when the Moon covers Venus about 2:30 in the afternoon on Tuesday, July 17. This event will be easily visible with binoculars or telescope because, at magnitude minus 4, Venus is visible in daylight.



Thursday, July 5th. Written by Peter Jennes.

During this Fourth of July weekend, Mars dominates the evening sky. At the other end of the day, Venus, Saturn, Mercury, and Jupiter are clustered near the eastern horizon just before dawn. In between the appearance of the major planets, the minor planet Ceres clears the eastern horizon as the Sun sets. Minor planets like Ceres are also known as asteroids. Most of the time, asteroids are very difficult to find as they are relatively dim. For the next two weeks however, Ceres will be relatively easy to find as it slides east-northeast of the bright star Zeta Sagittarii.

With a diameter of 580 miles, Ceres is the largest and first asteroid to be discovered. Ceres is so large that it is easily visible in binoculars if you know where to look. With Ceres passing near Zeta Sagittarii over the next two weeks, this may be your best opportunity to see this asteroid. To find Zeta, look for the teapot asterism of Sagitarius. Four stars of about third magnitude form the trapezoidal handle of the teapot. Zeta Sagittarii is the star marking the lower right corner of the handle. To make things easy to find, July's Full Thunder Moon sits just to the left of the Teapot's handle tonight.

To find Ceres, use the two bottom stars of the handle, Zeta and Tau Sagittarii, as a reference plane. Zeta and Tau Sagittarii are a little over two degrees apart. If you place these two stars in the upper right corner of a binocular field of view, you will see a sixth magnitude star about two degrees below both Tau and Zeta and forming a neat equilateral triangle with the two brighter stars. Tonight, Ceres is slightly dimmer than and 0.5 degrees to the left of this sixth magnitude star. By Saturday night, Ceres will be less than three arc minutes away from this star. At that time, you will be able to watch Ceres' motion against the background of stars. By 2 AM Sunday morning, Ceres approaches to within a few arc seconds of the star and the two objects will look like a close double star moving in fast motion. Night to night, you will be able to watch Ceres leave this sixth magnitude star and slide near to Zeta on the seventeenth.



Friday, July 6th to Sunday, July 8th. Written by John Schroer

Dudley Observatory - Skywatch

Sky watchers of the Capital district will have a bright sky to observe during this weekend. This brightening of the evening and night sky is due to Earth's closest neighbor, which is the Moon. Just a day and a half past its Full Phase, Earth's moon will be up all night long. On Friday July the sixth the Moon will rise at 8:51 PM; while on Saturday the 7th the Moon will rise at 9:35 PM. The Moon will rise on Sunday the eight of July at 10:12 PM.

Only one planet is visible to earthlings in the early summer sky. It can be spotted in the southeastern sky as a bright reddish light. Mars, the Red Planet, reached its closest point to the earth in its orbit around the Sun two weeks ago, and will be up for most of the night. Mars reaches its highest point in the sky, located due south, at 10:47 PM on Friday, 10:43 PM on Saturday, and 10:38 PM on Sunday.

The eastern sky is filled with many bright stars as the Summer Milky Way rises higher with each passing night. Look for the brightest one with a suggestion of blue in its light. Named Vega, it is the brightest summer star and is found in Lyra the Lyre or Harp. It is 27 light years away, or approximately 162 trillion miles from Earth. The rest of the constellation Lyra appears as a parallelogram or slight tilted rectangular box. At the short side of the box furthest from Vega you can spot a small ring shaped cloud or nebula. Known to astronomers as M57 or the Ring Nebula, it is the remains of a sun-like star that ran out of hydrogen fuel and died, blowing half of its material outwards in all directions.

The Albany Area Amateur Astronomers is an active group of hobbyists that explore the universe for the fun and excitement of exploration and sharing a common interest in the skies above. Anyone interested in exploring astronomy as a hobby should call Alan and Sue French at (518) 374-8460, or call the Schenectady Museum at (518) 382-7890, extension 236 for further information

You may find more information on the night skies over the Capital District by staying in touch with the Dudley Observatory Skywatch line or by visiting the Dudley Observatory web site at http://www.dudleyobservatory.org. Skywatch Line is Open Daily after 5 PM Monday through Friday all all day on the weekends.


Monday, July 9th. Written by Joseph Slomka.



Tuesday, July 10th. Written by Jonathan Cassidy.

The Moon approaches occultation of a bright body next Tuesday during the daytime. If it is clear we can all witness this as will happen July 17th. The Moon will pass between us and the planet Venus in the sky, this is called an occultation. We can all see Venus vanish behind the Moon and reappear later.

Locally the occultation will happen about 2:20 PM and reappear at about 3:20 PM. This is one of the few astronomy events you can see during the daylight. For you to see this happen you will need a site with a low south west horizon and good weather. You do not need any equipment though binoculars or a telescope would help. Around Noon find the thin crescent Moon in the sky, since it is a crescent it will be dim and not easy to find. If you have good eyes you will see Venus just to the left of the Moon, the rest of us will need binoculars or a telescope. Also watch for Mercury rising with Jupiter in the morning sky on July 13th. Also Venus near Saturn.



Wednesday, July 11th. Written by Ray Bogucki.

The planet Mars continues to dominate as the brightest object in the evening sky, other than the Moon. Currently Mars is located in the constellation Ophiucus (off-ih-YOU-cus) near the boundary with Scorpius. Ophiucus, which means "Serpent Bearer" is very large in area, almost 950 square degrees, but has no very bright stars. The main asterism in Ophiucus has roughly the shape of an old-fashioned, tall, metal coffee percolator. In addition to being the home of many globular star clusters, Ophiucus is the site of some interesting historical events.

In October of the year 1604 A.D., a brilliant star appeared from nowhere, near the southernmost, or bottom left star in the percolator. By coincidence, Jupiter and Mars were both very close to the site of the new star which was, in fact, the most recently recorded supernova explosion in our galaxy. When first seen it was as bright as Mars, but in a few days it became brighter than Jupiter. Both Galileo and Kepler studied the star, which has been called Kepler's Star in honor of Kepler's careful observations. Only six supernovae have been recorded in our galaxy in the past 1,000 years. At an average of one supernova every couple of hundred years, we are well overdue for the next occurrence.

In 1916, the American astronomer, E.E. Barnard, while comparing photographic plates made of the same region, near the "cap" of the percolator in 1894 and 1916, discovered that a small red dwarf star had moved an amazing 226 arc-seconds against the background stars. The star is known as Barnard's "Runaway Star" and has the greatest proper motion of any known star. In an average person's lifetime, the star will travel more than one-third the diameter of the full Moon. Barnard's Star is the second closest star to the Sun, at only 6 light-years and apparently has at least two Jupiter-sized planets.

A reminder for early risers: Next Tuesday, July 17, before sunrise, the waning crescent Moon will join Venus, Saturn and Aldebaran to form an elegant conjunction in the eastern sky. Then, in the afternoon, about 2:30, the sunlit leading edge of the Moon will occult Venus. Unlike an occulted star which disappears in an instant, Venus will take about 40 seconds to be completely covered and will then reappear, apparently from nowhere, from behind the Moon's invisible dark limb about an hour later.



Thursday, July 12th. Written by Peter Jennes.

As the sky darkens, the three stars of the Summer Triangle: Vega, Deneb, and Altair begin their march across the zenith. All of these stars are around first magnitude and stand out quite well, especially from suburban locations. Vega is straight up overhead with Deneb lower on the left. At the same time, Altair is nearly due south and about 45 degrees above the horizon. Because Altair is the middle star in a compact line of three stars, Altair is quite easy to identify. The star above Altair is called Tarazed while the star below is known as Alshain. Altair is brighter than either Tarazed or Alshain, while Tarazed is brighter than Alshain. According to Hindu mythology, these three stars are the Footsteps of Vishnu and represent the three steps with which the Hindu god crosses the heavens.

In western mythology, Altair, Tarazed, and Alshain are the three brightest stars in a celestial eagle that may have its origins in ancient Sumeria. Several scholars think this group of stars represented Alula, the great eagle sun spirit of Sumerian legend. By the time Greek society took center stage, the constellation became Aquila, but the stars remained the same and their form still represented an eagle.

Altair, the brightest star in Aquila, is less than seventeen light years away, making it one of the closest bright stars to our solar system. This pure white star is spectral type A7 which means it is a middle aged, main sequence star that is still converting hydrogen into helium. Altair is half again as large as our sun and over ten times brighter. Altair also has a velocity of 26 kilometers per second towards our Sun. Because it is so close and has such a high velocity, Altair speeds across the sky relative to the other stars and shifts position by over six tenths of an arc second per year.


Friday, July 13th to Sunday, July 15th. Written by John Schroer

Capital District stargazers have a lot of celestial events to witness during this weekend. The early evening sky is dark, due in part to the Moon not rising into our skies until late in the evening. On Friday, the Moon will rise at 12:24 AM, and will be in the last quarter phase. Only one half of our closest neighbor in space will be light by the sun.

Saturday will bring the Moon into view around 12:48 AM, while the Moon will rise at 1:14 AM on Sunday As it moves towards the sun and the completion of another orbit around the earth, the Moon is drawing ever closer to a wonderful gathering of four visible planets in the early morning sky. Look to the east and you will see Venus, Saturn, Jupiter and elusive Mercury gathered near the horizon around 4:30 AM. Saturn will be the highest in the sky, and has a distinct yellow flavor to its light. Just below Saturn is Venus, the brightest of all the planets. Much closer to the ground is Jupiter, and near the giant gas giant is little but bright Mercury.

The only planet visible to earthlings' eyes in the entire evening of summer can be spotted in the southeastern sky as a bright reddish light. Mars, the Red Planet, reaches its closest point to the earth during this weekend and is close to the constellation of Scorpius the Scorpion.

The Albany Area Amateur Astronomers is an active group of hobbyists that explore the universe for the fun and excitement of exploration and sharing a common interest in the skies above. This weekend features two public star parties, where anyone can look through many telescopes for free. Friday night's event is at the George Landis Arboretum in the town of Esperence. Start time is around sunset. The second star party is at the Sanders Preserve in Glenville on Saturday July 14th, also at sunset. Anyone interested in directions for the star parties or exploring astronomy as a hobby should call Alan and Sue French at (518) 374-8460, or call the Schenectady Museum at (518) 382-7890 for further information.

You may find more information on the night skies over the Capital District by staying in touch with the Dudley Observatory Skywatch line or by visiting the Dudley Observatory web site at http://www,.dudleyobservatory.org. Skywatch Line is Open Daily after 5 PM Monday through Friday.


Monday, July 16th. Written by Joseph Slomka.

The Sun sets tonight at 8:31, with night falling at 10:38. Dawn breaks at 3:28 AM and ends with sunrise at 5:33.

As the sky darkens, the Red Planet Mars is already risen and visible. Mars is now past its prime; it is slowly lagging behind Earth and grows dimmer and smaller daily. Mars is still large enough to see detail in telescopes, but time is now growing short. Mars is best seen at twilight's end, when it is due South and highest.

Pre-dawn skies stage a very interesting tableau. About an hour before sunrise, look East. Brilliant Venus is accompanied by a thin crescent Moon; Venus, itself, is a very fat crescent. Saturn is located above Venus, and the Hyades star group lies nearby. This is a great binocular object. The whole scene should fit in the five degree view of typical binoculars. Below and to the left, is the pairing of Jupiter and Mercury. These two planets are quite low, so trees and hills could block them.

There is a relatively bright visitor to our skies, Comet Linear. Comets are named after their discover; Linear is an automated telescope, not a person. The constellation Pegasus rises in the East about the end of twilight. The constellation is usually pictured as a flying horse, upside down. The Great Square forms its body, the neck extends southward and then up, Comet LInear is about halfway between the horse's nose and body. The comet is barely seen with unaided eyes in dark sites, but should be easily visible to suburban binocular viewers. Ordinary binoculars will see it. Carefully sweep the area between the body and the head; there are no galaxies or Messier objects to confuse you. That glow is the comet. Come Linear is probably a one time visitor, its orbit does not indicate a return. Comet Linear was first spotted much earlier, but was visible in southern skies only. Now the comet is heading out of our Solar System into the dim, cold regions of Uranus, Neptune and Pluto.


Tuesday, July 17th. Written by Jonathan Cassidy.

The elusive planet Mercury reaches its greatest illumination this week. Mercury is difficult even for professional astronomers to observe as it is so close to the Sun that it never appears in dark skies.

It can be found now in the morning twilight just 45 minutes before sun rise. Finding Mercury in the morning requires a low eastern horizon and a willingness to get up early, sun rise is about 5:10 AM. To find Mercury it is easiest to look for the thin crescent Moon on July 19th. Look just to the left of the Moon to find the only object this low shining through the twilight, this is Mercury.

The planet Jupiter is up and to the west or right of the Moon. Jupiter is returning to the night sky after passing behind the sun. We will mark the rise of Jupiter over the course of several months till it gets in place for good evening viewing.

Saturn is several degrees to the west of Jupiter, near Venus, and will be visible for evening observation first of these two. In the mornings now you can note the rise of both and may be glimpse Mercury and Venus also. Thus you can observe all six of the bright planets in one night (1: Mercury, 2: Venus, 3: Mars, 4: Jupiter, 5: Saturn) What is #6? Earth the brightest planet of them all.



Wednesday, July 18th. Written by Ray Bogucki.



Thursday, July 19th. Written by Peter Jennes.

Straddling the highest point of the northern Milky Way, Cygnus the Celestial Swan spreads its wings through spectacular star clouds holding abundant multiple star systems. Although light pollution dims the rich star fields, the best multiple stars of Cygnus are still visible under suburban skies. Two of the most prominent multiple stars in Cygnus are Beta Cygni and Omicron Cygni.

To find these star systems, look for the Northern Cross asterism of Cygnus. Around 10 PM, the Northern Cross lies midway between the horizon and zenith in the northeast. At that time, the Cross lies on its side with the asterism's longest bar nearly parallel to the horizon and the shorter bar almost perpendicular to the horizon. Having found the asterism, think of the four ends of the Cross as a clock face. With that in mind, Deneb, the brightest star of Cygnus sits at the 9 o'clock position. Beta Cygni, in the 3 o'clock position, lies nearly three times further from the intersection of the two bars as does Deneb. Beta Cygni is popularly known as Alberio; a name that probably originated as a corruption of Arabic words meaning "the beak." Considering that Alberio occupies the leading point of the Swan, this name is appropriate. The two stars that form Alberio have the combined light of a single third magnitude star.

Through a telescope, the brightest star of the pair shines with a golden light. The second star lies 34 arc seconds away and shines with a light described as azure blue. Through a telescope, the color contrast of this pair is simply beautiful.

Our second multiple star system, Omicron Cygni can be found using the short bar of the Cross. This bar represents the wings of the Swan and it stretches from Delta Cygni at the noon position to Epsilon Cygni at 6 o'clock. At the 10:30 position on the line between Deneb at 9 o'clock and Delta at 12 o'clock, lies the Omicron system. The Omicron system is made up of Omicron 1, Omicron 2, and 30 Cygni. Omicron 1 and 2 are about one degree apart and both stars are spectroscopic binaries of fourth magnitude. 30 Cygni is fifth magnitude and lies very close to Omicron 1.


Friday, July 20th to Sunday, July 22nd. Written by John Schroer


Monday, July 23rd. Written by Joseph Slomka.

This is the Skywatch for Monday, July 23. The Sun sets at 8:25 and twilight ends at 10:28 PM. Dawn breaks at 3:38 AM and and ends with sunrise at 5:59 tomorrow. As twilight falls, a thin crescent Moon is spotted in the West. Binoculars or telescopes show the Moon as heavily cratered and mountainous. Tonight, Moon gazing is especially significant. Thirty two years ago, Apollo 11 landed on the Moon - the first such landing. Our ideas about the Moon changed dramatically from that moment on. We now know that the Moon is made mostly of light rocks. The prevailing theory is the Moon formed after a Mars-sized body sideswiped Earth, and knocked off a layer of crust. It rapidly coalesced into the body we see nightly. Before Apollo 11, most scientists thought that the craters were old volcanoes. We now know that it underwent considerable cratering early in its history. This led to a reexamination of Earth history and the realization that large space rocks hit Earth in the past, and could do again in the future. The other significant heavenly body is Comet Linear. Tonight, the comet is fairly high in the East at twilight's end, and best seen at Midnight. If the constellation Pegasus is pictured as a horse flying upside down, Comet Linear is located between the horse's nose and fore legs. It should be faintly seen by the eye in dark skies, and by binoculars in suburban nights. Although comets are not usually classified as planets, most are members of our Solar System. They orbit the Sun in a regular pattern, just like the planets. A few comets are one time visitors, but most are regulars. Comets orbit the Sun in as little as every three years, or as long as 76 years, for Halley's Comet. Those who rise before sunrise will see an amazing lineup of planets in the East. Topmost is Saturn, a creamy white object about 37 degrees high. Venus is found to Saturn's lower left, followed by Jupiter, with Mercury hugging the horizon. Above this planetary parade is the lovely binocular object, the Pleiades.



Tuesday, July 24th. Written by Jonathan Cassidy.

Hercules rules tonight. Wouldn't it be good to be able to find other constellations beside the big dipper and Orion. Tonight you can do that with a relatively dim constellation.

The constellation Hercules is directly overhead tonight in the region of the sky we call the "zenith". To find it look for the bright stars Arcturus in the west and Vega in the east. These are the only two very bright stars at the top of the sky at dusk. Vega is the whiter of the two. One third of the way from Vega to Arcturus is a near trapezoid asterism Below it and using two of the same stars is another near trapezoid asterism.These two linked trapezoids form the body and legs of Hercules. He is most unfortunately upside down, if you are facing the south, with his head toward the north.

One arm extends toward Vega and the other toward the big dipper. Hercules holds a club in one of his hands and the skin of an animal in the other.

In Hercules just south of the west shoulder star is the brightest gobular cluster in the night sky. This is M13. This can be seen with binoculars from almost anywhere



Wednesday, July 25th. Written by Ray Bogucki.

With mid-summer approaching, the next few weeks provide our best opportunity to examine the region of the Milky Way that marks the center of our galaxy. On a clear, moonless night, far from city lights, the Milky Way presents a breathtaking spectacle, a bright band of light spilling down from Cygnus southward through Aquila and Ophiucus, into the vicinity of Sagittarius and Scorpius. The center of our galaxy is located a few degrees west of the spout of the "Teapot" asterism in Sagittarius. Careful observation of the area around Sagittarius with binoculars or a wide-angle telescope shows that this area is studded with many globular and open clusters and many nebulosities. There are also many peculiar, well-defined dark areas with almost no stars. While they look like open holes in the Milky Way, these dark areas are actually clouds of gas and dust that obscure all the stars behind them.

Theory predicts that the stellar density should steadily increase towards the galactic center with billions of stars crowded together in the bulge at the heart of the galaxy and, indeed, studies in the infra-red, which can penetrate the clouds, confirm that the stellar density approaches 5000 stars per cubic light-year. This is almost a million times the density in our neighborhood. For comparison a sphere of 60 cubic light-years surrounding our Sun would not contain any other stars. One might reasonably expect the high stellar density at the central galactic bulge to produce a great brilliance in the Milky Way near Sagittarius, but, unfortunately, vast clouds of gas and dust around the center almost completely block our view in the visible wavelengths.

It is fascinating to speculate what it would be like to live on a planet orbiting a star in the teeming central bulge of the galaxy with millions of super bright stars filling the sky. But, when we remember that the central point of our galaxy probably contains a large black hole around which many violent and destructive processes constantly occur, it is reassuring to be living in the quiet suburban backwaters of the galaxy, 25,000 light-years from the dangerous center. Our sky is glorious enough out here.


Thursday, July 26th. Written by Peter Jennes.

Once twilight has ended, the stars of the Summer Triangle appear high in the east. Sitting at the zenith, the highest and brightest of the three stars making up the Summer Triangle asterism is known as Vega. Vega is also the brightest star in the constellation Lyra. Lyra, like most northern constellations, had its origin in the stories of ancient mythology.

In Lyra's case, the ancient legends are associated with Greek mythology. In the Greek myth, these stars were the musical instrument known as the lyre, an instrument similar to the modern harp only much smaller. In the Greek legend, the poet Orpheus owned this lyre. Orpheus played music so sweet that kings paid great sums to hear him play.

After one of these trips to play for a king, the crew of the ship taking Orpheus home asked the poet to play his lyre. The music was so beautiful that dolphins swam up to listen. Later, the crew realized how much gold Orpheus was carrying and stole it. They then threw Orpheus and his lyre into the sea. However, the dolphins saw what happened and came to rescue Orpheus. As soon as he was safe on shore, Orpheus told the king his tale. When the ship returned to port, the king put the sailors to death for their crime and returned the gold to Orpheus.

Today we see this sky story as the constellations Lyra, Delphinus the dolphin, and Cygnus. Although we now thing of Cygnus as a swan, the Greeks recognized these stars as both a swan and as Orpheus. All of these constellations are in or near the Summer Triangle. Lyra has the shape of a parallelogram that hangs below Vega, the brightest star in the summer sky. The stars of Orpheus start at Deneb, the lower left stars of the Summer Triangle. From there, Orpheus is outlined by the Northern Cross asterism of Cygnus. The last player in this legend, Delphinus, lies just below the Summer Triangle. This constellation stands out as a small diamond of fourth magnitude stars with a tail of equally bright stars curving of to one side. As you look at these stars, it is easy to see how the ancient Greeks saw a leaping dolphin in their shape.



Friday, July 27th to Sunday, July 29th. Written by John Schroer

The Capital District can look forward to seeing an M & M sky for the next three days.

Early in the evening, around 9:30 PM, you can find the two brightest objects close together in the southern sky. In the constellation of Libra the Scale you will locate the first quarter Moon. This is when our neighbor in space has complete 25 percent of its orbit around earth, and only half of the side facing towards the earth is being lit by the Sun. Observing the Moon during this weekend will allow you to see the moon sunlit portion grow, as it continues towards the Full Moon phase in approximately seven days.

The second M of this weekend's sky is the Planet Mars. Now in the constellation of Scorpius the Scorpion, you can see two red objects. One is very bright, and if you watch this light over several weeks, you will notice that this object is slowly moving amongst the stars. This object is the planet Mars, which is very close to a dimmer red light . This is the bright red Star Antares, the so-called Heart of the Scorpion. It has been nearly a month since the red planet passed its perihelion, or the location of its orbit where Mars is closest to the Sun. Mars is currently experiencing some stormy weather, with a large dust storm brewing.

The Moon will rise at 1:39 PM on Friday, 2:47 PM on Saturday, and 3:53 PM on Sunday. The Moon will set at 12:31 AM on Friday, 1:02 AM on Saturday, and 1:37 AM on Sunday.

The Union College Department of Physics is hosting its monthly open house at the Union College Observatory on Saturday, July 28th from 10:00 PM through 11:00 PM. The Observatory is located on the campus of Union Collge.


Monday, July 30th. Written by Joseph Slomka.

The Sun sets tonight at 8:18; night falls at 10:16 PM. Dawn breaks at 3:49 AM, tomorrow, with sunrise taking place at 5:46.

As the sky darkens, the Moon first becomes visible in the South. Mars later becomes apparent to the Moon's right. The Red Planet continues to be the nightly draw. Although slowly growing smaller and dimmer, Mars has a few months good observing left. One can still observe surface features from a telescope; binocular observers see Mars surrounded by star clusters and glowing gas clouds.

Pre-dawn skies show Saturn next to the lovely Hyades star cluster. Brilliant Venus is found to Saturn's lower left, followed by Jupiter. Mercury rises before sunrise and may be hidden by trees and buildings.

All the objects mentioned are members of the Solar System. Other members do not appear regularly, these are comets and meteors. Comet Linear is currently gracing our skies. Tonight it is found to the left of the tiny constellation Delphinus, the Dolphin. Observers from suburban or rural locations can find it with binoculars. Comets are balls of ice and rock that orbit the Sun. Some have orbits that return them to the inner Solar System; other orbits take them in for one-time appearances. Meteors are also solar system members. They are usually bits of comets, asteroids, or other left overs from the early formation of the Solar System. When a meteor becomes trapped by Earth's gravity, the meteor becomes a streak of light or a fireball as it burns through our atmosphere. Most meteors are the size of a grain of sand, and never make it. Larger ones may survive as pebble or stone sized meteorites, the name for surviving meteors. A week ago, a meteor brightly appeared in daytime and was travelling northwest, accompanied by sonic booms. Amateur and professional astronomers are now scouring the New York-Pennsylvania border for fragments. It is estimated that the meteor was about the size of a car. Such meteors are not unusual, but most arrive over oceans.



Tuesday, July 31st. Written by Jonathan Cassidy.

The Summer triangle is becoming prominent now. The triangle is made up of Vega, of the constellation Lyra, Deneb, of the Cygnus, and Altair, of Aquila. Of these Vega is the brightest and the only bright star at the zenith at sunset.

Altair is to the south and Deneb to the East. Altair and Deneb are of similar brightness and brighter than most of the other stars in the sky. As the Moon approaches full these three stars will still stand out in the glare of the Moon.

Near Vega is a small parallelogram of similar brightness stars , two near Vega and two about three fingers away. Between the two southern stars, of this parallelogram, lies a planetary nebulae that can be seen in most telescopes of 4" or larger. This is the Ring Nebulae or M57. It is a ring of gas surrounding a dead star. It is said by professional astronomers that our sun will end it's life this way in 3 - 5 billion years.

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