Skywatch June 2001

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

Friday, June 1st to Sunday, June 3rd. Written by John Schroer

Monday, June 4th. Written by Joseph Slomka.

  The Sun sets at 8:30 tonight, with night falling at 10:42. Dawn breaks at 3:06 AM and ends with sunrise at 5:18.

As the Sun sets Mercury and Jupiter are located very low on the northwestern horizon. If the horizon is clear, this is probably your last chance to view these planets for a while. The nearly Full Moon rises in the East and remains up all night.

Planet observers must wait until predawn skies. Mars rose a bit after twilight's end, but is best seen after midnight. Mars is steadily gaining size and brightness. It is easily the brightest object in the southern sky. This is Mars' closest approach in 13 years. Telescopes show a wealth of detail. Mars is nearest on June 13, but reaches its own equinox on the 17th. Thus, telescopic observers can see from pole to pole, including the southern ice cap.

About 4:00 AM, is an ideal time to observe Mars, Venus, Uranus and Neptune. Mars is found in the southwest, while Venus is located in the southeast. Venus outshines Mars, but its pale, thin crescent is no match for the Red Planet. In telescopes, Venus is perpetually clouded, while Mars presents a wealth of surface detail.

Another planet is reaching opposition but most people will never see it. Pluto is a dim 14th magnitude object on the Ophiuchus border. Pluto is a small planet, composed mostly of frozen water and gases. It has a moon, Charon, so large that it is almost a double planet system. This distant planet orbits the Sun every 247 years. Pluto is so dim and distant that< it was discovered only in 1930 by Clyde Tombaugh after an exhaustive and frustrating search. Pluto is not like the other planets in many respects. Its orbit is more at an angle, and more elliptical. If you want to find Pluto, you must first have access to an ten inch or larger telescope and a very accurate map, usually found in astronomy magazines.

Tuesday, June 5th. Written by Jonathan Cassidy.

The moon is near full so most of the stars of the sky will not be visible. The full moon is the second brightest thing in our sky after the sun.

Near the zenith of the sky as twilight ends you will find a line of three stars in a curve. These stars are of near equal brightness and form the handle of the Big Dipper.

As it gets darker notice the middle star of the handle. Do you see the companion star? It is quite dim to the unaided eye. The bright star is Mizar and the dim one Alcor. Binoculars will help to see it better. A telescope will show that there are three prominent stars of different brightness in a triangle. The brightest of these can be seen as a tight double star. Mizar and Alcor are always above the horizon as they are not far from Polaris and the north celestial pole.

Ancient civilizations used this double star set as an eye test. Those who could see and describe the double stars and their orientation to each other were allowed to go out on hunting and warring parties with edged weapons.

Wednesday, June 6th. Written by Ray Bogucki.

Tonight, when the just-past-full Moon rises about 9:30, look for Mars, gleaming orange just a few degrees to the right, or south, of the Moon. One week from tonight, when the Earth overtakes Mars and passes between Mars and the Sun, Jupiter will be passing behind the Sun, while Mercury prepares to dart between the Earth and the Sun. Thus, a fortuitous coincidence in orbital motions will produce an excellent alignment of solar system bodies in the order: Mars, Earth, Mercury, Sun and Jupiter. This month Mars moved from the constellation Sagittarius into Ophiucus, where it shines against a background of star clouds in the Milky Way, not far from the rotational center of our galaxy. The activity at our galactic center is of vital interest to astronomers, but unfortunately, it's light is obscured by vast clouds of dust so that very little information can be obtained from optical telescopes.

On the other hand, radio waves, with their much longer wavelengths, pass through dust clouds with minimum interference. Radio telescopes can also operate in cloudy weather and in broad daylight. To take maximum advantage of these capabilities, the National Radio Astronomy Observatory has recently inaugurated a cutting-edge system known as the Very Long Baseline Array, a collection of ten identical, parabolic radio "dish" antennas stretching across 5,000 miles from Hawaii to the Virgin Islands. By ingeniously combining the data from all ten dishes observing the same object, astronomers can produce images with a resolution better than a thousandth of an arc-second, sufficient to read a newspaper in New York from the distance of Los Angeles. Such radio telescopes have provided much of our information about our galactic center, black holes and those mysterious objects known as quasars, which are usually billions of light years away, and may be very faint in visible light, but "bright" in radio frequencies.

To perform your own radio astronomy experiment, take an FM radio outdoors and set the dial to a dead spot, a frequency not used by any local broadcaster. The loud, constant hiss will be interrupted occasionally by a sudden clear burst of broadcast sound which will rapidly fade in a second or so. When a meteor streaks across the sky at, perhaps, 100 kilometer altitude, the train of ionized atoms and molecules it generates can reflect a signal from a radio station that is far too distant to reach your receiver by line-of-sight transmission. This method for detecting meteors is much more sensitive than visual observation and works equally well day or night.

Thursday, June 7th. Written by Peter Jennes.

Shortly after 10 PM, the moon rises above the southeastern horizon and forms a straight line with Mars and Antares. As you observe this alignment it will be easy to see that Mars is at the mid-point of the line. What isn't so apparent is why the moon and Mars are so close. The celestial mechanics behind this close appearance are based on the position of the full moon and the fact that Mars is approaching opposition. Tonight, the moon is just past full and when the moon is full, it is opposite the Sun in our sky. In exactly the same way, when a planet is at opposition, it is also opposite the Sun in our sky.

Since the moon is just past opposition, and Mars is just approaching opposition, it follows that both objects should appear near each other in the sky. Whenever a planet is at opposition, it is also about as close to Earth as it can get. This makes the time around opposition the best time to observe a planet through a telescope. In fact, the two weeks on either side of opposition are about the only time you stand much of a chance of seeing surface features on Mars through a small telescope. While your telescope is out, make sure to point it at the moon.

Tonight the terminator touches the eastern shore of the circular Sea of Crises. Because of that, the ring of mountains surrounding the Sea of Crises should stand out in shadowed relief. Some theories attribute this ring of mountains to an ancient impact that also created this lunar basin. Several craters dot the floor of Mare Crisium and four of these should be visible at high magnification. From north to south, the craters are, Swift, Pierce, Picard, and Greaves. Of the four, Picard is the easiest to find because it is both the largest, and it has a distinctive rim. At 7 miles in diameter, Swift is the smallest of the group. Greaves is just slightly larger than Swift and Pierce is just slightly smaller than Picard. Many other interesting craters are visible north and south of the Sea of Crises so take your time exploring this region.

Friday, June 8th to Sunday, June 10th. Written by John Schroer

The skies over the Capital District will begin to darken, thanks to the Moon passing its full phase 5 days ago. By Friday evening the 8th, the Moon will not rise until 3 hours after sunset, giving local skywatchers some time to explore the heavens without moonbeams. The early riser can observe the planet Venus reach its furthest elongation from the Sun 1 hour and 15 minutes before sunrise, at 4:05 AM. Look just due east for the brightest object, and you will have found Venus. Friday's skies include the bright planet Mars, now located in the southeastern sky. You can find the Red Planet as the brightest object in the southeast, and located just to the left of another red light in the sky, the star Antares. Known as the Heart of the constellation Scorpius the Scorpion, Antares' name means the rival of Mars.

Antares is the 15th brightest star in the heavens, and is a fine example of a red supergiant star. These monster sized stars are hundreds of times larger than the Sun, but are not exceedingly bright. Only one other star joins Antares in the order of the brightest stars in the sky, known as 1st magnitude. That is Betelgeuse, the red shoulder star in the winter constellation Orion the Hunter.

On Saturday evening, telescope owners observing Mars should be on the lookout for Syrtis Major, the most prominent dark feature on the Red Planet. It will be centered on the disk of Mars on Saturday Morning at 1:05 AM, and Sunday morning at 1:41 AM. This difference in times for the appearance of Syrtis Major is due to the slightly longer day on Mars. The Martian day is 24 hours and 36 minutes long. The telescope observer can watch Martian features more at 14.6 degrees every hour, and see them again the next day, but 36 minutes later.

Sunday's skies feature the last stars of Winter, now disappearing into the northwestern horizon. Around 9:40 PM, look for two stars side by side, with the left star a little brighter than the one on the right. These stars are Castor to the right, and Pollux to the left, marking the heads of Gemini the twins. Pollux is a little closer to Earth, at 33 point 73 light years or more than 202 trillion miles away; while Castor is about 51 and a half light years or more than 309 trillion miles away. To the right of Castor and Pollux is the bright star Capella, in the constellation of Auriga the Charioteer.

Please be sure to call the Skywatch Line for more information on the skies of the Capital District, supported by the Dudley Observatory.

Monday, June 11th. Written by Joseph Slomka.

The Sun sets tonight at 8:34, but the sky becomes darkest at 10:50 PM. Dawn breaks at 3:05 AM, and ends with sunrise at 5:16.

As the Sun sets, no planets are visible, although Mars rises slightly after sunset. Mars clears houses and trees about the time of twilight's end. By that time it is very easy to find Mars, it is the bright red object in southern skies. Midnight is the best time to observe Mars, it is at its highest. Mars reaches opposition on Wednesday evening, when it is in direct line with the Earth and Sun. One the seventeenth, Mars has its own equinox; so telescope observers can see from North Pole to South Pole. Mars is closest to earth next week, when its biggest and brightest. Even if you observe Mars with your eyes, it is a glorious sight. Astronomy magazines are full of tips for those observing with binoculars and telescopes.

Venus rises shortly after dawn begins. By sunrise, it is well up in the east. Even in binoculars, Venus is half illuminated. Unlike Mars, even high power telescopes reveal little about Venus. All you see is a uniform cloud cover - the effects of a runaway greenhouse effect.

Rising tonight, during twilight, is the constellation Hercules. This constellation is ancient and shrouded in mystery. Even ancient Greeks were not sure of the constellation's origin. Hercules was half-man and half-god. His ancestry is uncertain; his alternate name, Heracles, implies that the goddess Hera was his mother. What is certain is that Hercules was very strong and very prominent in Greek myths. His twelve labors are related to the Zodiac. Many Zodiacal creatures figure in these legends. Hercules is normally depicted as upside down in the sky, with his foot on Draco. He is usually recognized by the "keystone" in the constellation's center. Hercules is a favorite of astronomers, because many different objects are contained within its borders: red giant stars, binary stars, triple stars, eclipsing stars, variable stars, globular star clusters and many galaxies.

Tuesday, June 12th. Written by Jonathan Cassidy.

The first stars to pop out of the twilight sky at this time of the hear are Arcturus and Vega. You will find these with Arcturus near the zenith and Vega to the east, but still toward the top of the sky. You will see these while the twilight is still fading.

Once darkness settles in you should notice that there is a color difference between these two. Indeed though they are of similar brightness Arcturus is more yellow or golden. This means that the surface temperature is cooler. It is probable that Arcturus has burned through more of its nuclear fuel.

Once it is fully dark look along the line from Arcturus to Vega for a "horse shoe" curve of stars. This is the constellation Corona Borealis, "crown of the north". It should be directly over head between 9 and 11 PM. Once you see it you will never forget it as there are no curves so obvious and easy to see. The crown is open to the north east and the brightest star is to the south west.

Wednesday, June 13th. Written by Ray Bogucki.

Tonight the red planet Mars stands at opposition. Because the Earth lies between Mars and the Sun, the planet will rise at sunset and set at sunrise, remaining visible throughout the night. The next few weeks will present the best opportunity in 13 years to see markings on Mars' surface. The Martian southern hemisphere is moving from winter into spring and its southern pole should show a prominent white seasonal polar cap made mostly of solid carbon dioxide or dry ice with a little water ice. This southern polar cap may reach halfway to the equator in midwinter and then disappear in the summer, except for a small residual cap of carbon dioxide. The northern pole also undergoes a seasonal expansion of solid carbon dioxide, but its permanent residual cap is mostly water ice that is probably hundreds of meters thick.

Unfortunately, even on nights of exceptional clarity, earth-based telescopes can, at best, see vague, dark markings and sometimes the bright polar caps on the surface of Mars. Images from the Hubble Space Telescope show much clearer outlines of Martian features but without fine details. The really exciting images of Mars, sent by the various Mariner and Viking probes and the Viking and Pathfinder Mars Landers, show a world of superlatives. Like a massive scar across the middle of the planet lies the Mariner Valley, an incredibly huge canyon stretching for almost 2500 miles. It is 6 times wider and almost 4 times deeper than the Grand Canyon. Going in the opposite direction, we have Olympus Mons, the largest volcano known on Mars or anywhere else in the solar system. It is roughly the size of Texas at its base and rises a majestic 15 miles into the Martian sky, almost 3 times taller than Mt. Everest on Earth.

Closer to home, a rock, presumably blasted from the surface of Mars 16 million years ago, was recovered in 1984 from the Antarctic ice where it apparently had lain for 13,000 years. Photomicrographs of the rock show tiny rod-like structures which have been interpreted by some astronomers to be fossilized microscopic life forms. This interpretation is hotly debated and final conclusions about previous life on Mars will probably have to wait until we launch a manned mission to the Red Planet sometime early in this century.

Thursday, June 14th. Written by Peter Jennes.

Friday, June 15th to Sunday, June 17th. Written by John Schroer

The skies over the Capital District during June 15th through the 17th will feature a beautiful gathering in the early morning and a fast moving planet moving among the stars of Sagittarius and Scorpius.

The Moon will be in its waning or shrinking crescent phase for the weekend, and will not rise until 2:20 AM, giving local skywatchers the evening to explore a dark sky when away from city lights.

Friday's skies include the bright planet Mars, now located in the southeastern sky. You can find the Red Planet as the brightest object in the southeast, and located just to the left of another red light in the sky, the star Antares. Known as the Heart of the constellation Scorpius the Scorpion, Antares' name means the rival of Mars.

Careful observers can witness Mars in motion at the rate of one third of a degree each night. This apparent moving is caused by our planet overtaking Mars, making Mars look like it is going backwards. Mars will continue to move closer to Antares until the backwards motion of Mars stops on July 19th , just 5 degrees east of Antares.

Saturday will feature a gathering of two planets, the Moon, and a star cluster. The early riser can observe the planet Venus, the brightest object in the eastern sky, between the crescent Moon above, and the Pleiades star cluster below at dawn. Look just above the east by northeastern horizon at this time, and you will see Saturn, now visible for the first time since it's moving by the sun. Each week you will see Saturn moving closer and closer to Venus as we see it from the Earth.

The telescope observer can watch Martian features more at 14.6 degrees every hour, and see them again the next day, but 36 minutes later.

Sunday's skies feature Venus and the shrinking crescent Moon close together at dawn, and the first stars of Spring are now in the West. Leo the Lion is now due west, moving towards the horizon. Leo was known as the Herald or announcer of the Spring Season, during the days before printed calendars were in common use. Look for the backwards question mark, which is the head and mane of the lion. The question mark is the bright star Regulus. Located 77 point 6 light years from the earth, Regulus is 4 times larger than the Sun and as right as 197 suns.

Please be sure to call the Skywatch Line for more information on the skies of the Capital District, supported by the Dudley Observatory.

Monday, June 18th. Written by Joseph Slomka.

The Sun sets at 8:37 PM, and night falls at a very late 10:54. Dawn breaks very early at 3:02 AM tomorrow, and ends with sunrise at 5:17.

No planets are seen as the Sun sets. Mars rises a bit before sunset, but is best seen at end of twilight or midnight, when it clears trees and hills. Even so, Mars is fairly low in the sky. Mars will reach closest approach to Earth later this week. As a result, it is now the brightest object in the sky, even brighter than the star Vega, traditionally the brightest object in summer skies. Binoculars show Mars as a bright red ball, but a telescope is needed to see features on the planet's surface.

Shortly before sunrise, Venus, the Moon and Saturn align. Venus is high in the East. At magnitude -2.8, there is no mistaking Venus. The thin crescent Moon appears to Venus' lower left, and Saturn peeks above the horizon to the Moon's lower left. This is Saturn's first appearance since it was hidden by the Sun for a month.

High in the eastern sky at 10:30 PM is the constellation Lyra. It is easily found because its star Vega, is the brightest in the sky. Lyra looks like a triangle atop a rectangle. Among the smallest constellations, it has an ancient history. The name "Lyra" means "lyre", the legendary harp whose music calmed beasts. "Vega" is an Arabic name, meaning "swooping eagle." The Arabs depicted Lyra as an eagle or falcon. Vega is the fifth brightest star, about 27 light years distant. Twelve thousand years ago it was the Pole Star. Between the bottom stars in Lyra lies the planetary nebula M 57, The Ring. This is the remnant of a star which lost most of its mass; all that remains is a ghostly ring around a central star. M 57 can only be seen in a telescope, and is a favorite of star parties.

Tuesday, June 19th. Written by Jonathan Cassidy.

The moon is near new this evening. With out the glare of the moon we can look for dimmer objects. As the moon's month goes by notice the difference of the night sky with the difference of the light glare of the moon.

Looking directly up at the end of twilight there are two stars that stand out: Arcturus near directly over head and Vega to the east. In a line from Arcturus to Vega two thirds of the way toward the latter there is a keystone asterism of stars. This should be near the zenith this week.

This keystone is prominent once the sky is dark. Using binoculars look at the line from one star to another in the keystone. Along one of the long sides you will find a "fuzzy" object that is not like all the stars around it. This is M13 a globular cluster. There are hundreds of thousands of stars in this cluster. They are so close together that they look like a single cloud in binoculars or a small telescope. Large telescopes reveal individual stars.

Wednesday, June 20th. Written by Ray Bogucki.

Tomorrow marks a momentous day for astronomers, with three major events. Three and a half hours past midnight tonight, the Sun reaches its farthest northern declination for the year, generating the summer solstice in the northern hemisphere, and the winter solstice in the southern hemisphere. About four hours later, the new Moon will pass directly in front of the Sun's disk, producing the first total solar eclipse of the third millennium, visible from parts of southern Africa. Then tomorrow evening, Mars reaches its closest approach to Earth since 1988, a little less than 42 million miles. It will shine with a dazzling magnitude of minus 2.2 and present a large disk of 20.8 arc-seconds.

It is fairly common knowledge that tomorrow's solstice will present us with the longest day of the year in terms of sunlit hours. Less well known is the fact that the earliest sunrise of the year occurred almost a week ago, and the Sun will continue to set later each day, until the latest sunset occurs a week from tomorrow. This lack of symmetry in earliest sunrise and latest sunset is due to the tilt of Earth's axis of rotation and the variable speed of the Earth in its elliptical orbit.

It is interesting to consider the behavior of the Sun at various locations on the Earth at the summer solstice. All inhabitants living on or north of the Arctic circle, at 66.5 degrees north latitude, will experience 24 full hours of sunlight tomorrow. The altitude of the Sun at noon will be 23.5 degrees at the north pole and 47 degrees at the Arctic Circle. In the north temperate zone, the Sun will stand at its highest for the year, at noon. For example, at Albany, at 43 degrees north latitude, the celestial equator is always at its maximum elevation of 47 degrees above the horizon when one faces due south. Since the Sun is 23.5 degrees north of the celestial equator at the summer solstice, the Sun reaches its maximum noon elevation for the year of 70.5 degrees at Albany.

Those living along the Tropic of Cancer, at 23.5 degrees north latitude will see the Sun climb precisely to the zenith at noon. It may seem surprising, but for those living on the equator itself, the Sun will climb to only 66.5 degrees at noon, which is 4 degrees lower, and thus less intense, than it is in Albany on that day.

Thursday, June 21st. Written by Peter Jennes.

The first sunset of summer occurred at 8:37 tonight. As the Sun was setting, a brilliant red Mars was rising in the east. As it was rising, Mars was as close to the Earth as it will be for the next two years. Earlier today, the Sun reached its northern-most point in the sky. When the Sun reaches this point, summer officially begins. However, in ancient times, our first day of summer marked many culture's first day of the midsummer's celebration. This solstice feast began when the sun reached its most northern elevation and ended when the latest sunset occurred.

The most important day of the solstice celebration came on Midsummer's Day. This occurred when the sun's most northern reach was four days past, and the latest sunset was three days away. That day marked the midpoint of the solstice season. Being such, this day was given the magical status of Midsummer's Day by the ancients. Festivities started a night earlier on Midsummer's Eve. That night was marked by giant bonfires, feasting and ritualistic dancing.

The bonfires were lit to entice the sun to stay and in their flames, effigies of winter were burned. Celebrants jumped through the fires thinking the magic of the flames would be transferred to them. The great light and merriment around the fires was also thought to drive away evil, leaving the earth open for good spirits to roam freely. These were celebrations of victory and fertility.

With dawn on Midsummer's Day, livestock was herded through the ashes of the bonfires. Doing so, the magic left from the flames would give good fortune to the herd. Embers were taken from the ashes, and the hearths at home were rekindled. Midsummer Day was concluded by ceremonial bathing and playful water fights.

As society evolved, what were seen as pagan rituals became unacceptable. Beliefs were converted by incorporating the rites of old into accepted ceremonies. For instance, the ritual bath was assimilated into the practice of baptism. Thus Midsummer's Day became known as the feast of Saint John the Baptist. While thinking of humanity's development as you watch the sun begin its' yearly southern drift, take a moment to reflect on how nice it is that the yearly bath is a thing of the past.

Friday, June 22nd to Sunday, June 24th. Written by John Schroer

The sky gazers of the Capital district are greeting the stars of summer during this weekend. The planet visible to earthlings' eyes for the 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 eastern sky is filled with many bright stars as the Summer Milky Way rises higher with each passing night. Look for three bright stars, named Vega, Deneb, and Altair, forming the popular asterism known as the Summer Triangle. Each of these bright stars belongs to their own constellation. Altair is the eye of the eagle Aquilla, while Deneb is the tail star of Cygnus the swan, and the brightest star and highest of the three is Vega, in Lyra the Harp.

Altair is the closest of the three to earth, at a distance of 12 light years or 72 trillion miles, with Vega next at 27 light years of 162 trillion miles, and Deneb is the most distant at one thousand six hundred light years from our home. The light we see from Deneb departed from that star in the year 401 A.D.

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 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, June 25th. Written by Joseph Slomka.

The Sun sets tonight at 8:38 PM. Dawn breaks at 3: 04 AM and ends with sunrise at 5:19 tomorrow.

As the Sun sets, the Moon is fairly high in the West. It is about one quarter illuminated and waning. Tonight the Moon is located in Leo about halfway between the bright star Regulus and his tail star, Denebola. Mars is also up, but too low for useful observations.

By twilight's end, Mars is ideally situated due South. The Moon is almost set and poses little problems for the observer. Besides Mars, the constellations Sagittarius and Scorpius offer many sights for the binocular viewer. The Lagoon and Triffid nebulas rise like steam from the Sagittarius' "spout." The objects M6 and M7 are beautiful star clusters that hover just above the Scorpion's "stinger."

Pre-dawn observers can look East and spot Venus, the brightest object. In binoculars, Venus appears over half illuminated. The beautiful asterism, the Pleiades, lie just to the Moon's left, again, another great binocular object. Saturn hovers sixteen degrees above the horizon. Most amateur binoculars are too small to see Saturn's rings, but the planet will definitely not be a round ball, as Venus and Mars appear.

Two themes populate the night sky at this season. During Summer, flying is a major theme. The most prominent flying constellation is Cygnus, the Swan. Cygnus is the cross-shaped constellation overhead. The Eagle, Aquila, appears directly south of Cygnus. The most famous flying constellation is just rising, Pegasus, the Flying Horse. Only one inanimate constellation is included - Sagitta, the arrow, which flies between Cygnus and Aquila. The other theme for early Summer is that of heroes. Three Greek heroes are featured in tonight's sky. Ophiuchus struggles with the snake Serpens high in southeastern skies; he is also a healer, credited with many cures. Hercules shares the skies as the strongman who triumphed in twelve legendary labors. Finally, Perseus rises after midnight; he tamed Pegasus, slew the sea monster Cetus, and saved the fair maiden Andromeda.

Tuesday, June 26th. Written by Jonathan Cassidy.

We are now near the longest day of the year. This means the night is the shortest. We have the least time to observe objects in the night sky. Though winter is cold we have then the longest time to observe the night sky. Unfortunately objects of the summer sky are not available to be seen in the winter. Each season has its own treasures for your viewing.

Tonight we have a waxing crescent moon. After it gets fully dark look to the south. You will notice that there are two bright orange objects. One is a planet and one is a star. The planet is Mars, known by some cultures as Ares. The star is Antares or "anti Ares", that is the rival of Ares or Mars. It is the rival in color. Antares is the heart of the constellation Scorpius.

With binoculars or a telescope there are many delightful objects to see near Antares and Mars. Just cruise around the area and marvel at what you see.

Wednesday, June 27th. Written by Ray Bogucki.

The word "planet" derives from ancient Greek and means "wanderer". Early astronomers were fascinated by these restless "stars" that wandered in curious ways among the fixed stars that kept their relative positions, and made it possible to recognize the same constellations year after year and century after century. Because the orbital planes of the other planets all lie close to the orbital plane of the Earth, the planets' wanderings never stray very far from the Sun's annual path through the twelve constellations of the Zodiac.

Last March, Mars, in its normal eastward orbital motion, passed close to its ancient rival, the bright red star Antares, the heart of Scorpius the Scorpion. As the Earth, with its faster orbital speed is passing Mars, the red planet appears to be moving backwards, or westward, back towards Antares.

In mid-July it will cease its retrograde motion just 5 degrees east of Antares and then resume its normal, slow eastward movement through the stars for the next two years. At its next opposition in August 2003, Mars will be in the constellation Aquarius. It will be 7 million miles closer and will stand higher above the horizon, providing greatly improved viewing.

The name "Antares" means "rival of Mars" and was given by early astronomers who noticed that when Mars passed through Scorpius, Antares often appeared very similar in color and brightness to Mars. During the current passage however, Mars shines 20 times brighter than Antares. The relative brightness of Mars, of course, follows from its proximity to Earth. While it takes only 4 minutes for light to reach us from Mars, it requires 600 years for light from Antares to arrive. Antares is nearing the end of its stellar life and has expanded into a red supergiant whose diameter is about 700 times that of the Sun. If Antares were placed where the Sun is located, Mars would be orbiting well beneath the surface of the star. It is fascinating that its immense size brings the average density of Antares to roughly one-millionth of the density of the atmosphere on Earth, which would be considered a good vacuum here.

Thursday, June 28th. Written by Peter Jennes.

On January 15th of this year, Project LINEAR detected a 16th magnitude object moving into the inner solar system. At first, astronomers thought this object was a new asteroid. However, over the next two weeks, the new object developed a faint coma and slowly brightened. Having made these observations, astronomers realized the object was actually a comet they calculated the objectís orbit and gave it the name C/2001 A2 LINEAR.

Although both asteroids and comets have elliptical orbits, there is one fundamental difference in the way a typical asteroid orbits the Sun when compared to the way a typical comet orbits the Sun. Typical asteroids have an elliptical orbit that appears almost circular. In comparison, the elliptical orbit of an average comet looks more like a parabola rather than a circle as the comet approaches the Sun. In the case of LINEAR A2, astronomers calculated that the comet would slip inside the Earth's orbit and pass about 73 million miles away from the Sun on May 24th while remaining a relatively dim magnitude 10.

Early on, Comet A2 LINEAR slowly brightened and behaved almost exactly as predicted. Then during the last five days of March, the comet suddenly brightened from magnitude 12 to magnitude 7. Almost as quickly, the comet faded back to magnitude 9 in early April. By late April, LINEAR A2 was still dim and for northern observers, it disappeared into the sunset. As luck would have it for northern observers, just as the comet was lost to the Sunís glare, it again brightened dramatically. For observers located south of the equator, the story was quite different. Day by day, LINEAR A2 climbed higher in the southern sky and by mid-April the comet was a third magnitude naked eye object with a visible tail. As the comet reached maximum brilliance, observers noticed that the nucleus had split into three pieces. Comet LINEAR A2 is now returning to northern skies during morning twilight. The comet has faded to fourth magnitude but should be visible through binoculars. Although it will be difficult to spot, interested observers should spend some time looking for this comet as it could undergo another dramatic brightening at any time. Finder charts and celestial coordinates are available from several Websites and skypub.com is a good place to start.

Friday, June 29th to Sunday, July 1st. Written by John Schroer

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