Skywatch January 2003

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

Wednesday, January 1st. Written by Ray Bogucki.

Last night, people around the world welcomed the new year. Just at midnight, as fireworks were set off, our own celestial sparkler, Sirius, the brightest star in the sky, marked the event by making its transit across the southern meridian, reaching its highest point in the southern sky.

Tonight, between sunset and sunrise, all five bright planets will be visible. As the sky darkens, look for Mercury, preparing to set, low on the southwestern horizon. In the northeast, Saturn, near the southern horn of Taurus, is climbing into the eastern sky. By 8 p.m., Jupiter is rising in the northeast, close to the "Beehive" star cluster in Cancer. At 4 a.m., when Venus and Mars rise close together in the southeast, four planets are visible at one time.

The coming week will witness several notable events. Friday evening, the Quadrantid meteor shower will reach its peak. This shower can produce as many meteors per hours as the better-known Perseid meteors of August. There are two mysteries connected with this shower; the name, and the parent comet.

The name, Quadrantids, implies that the radiant, the point from which the meteors apparently emanate, is in a constellation named the Quadrant. Indeed, during the 18th century, a small group of stars, a little to the east of the end of the handle in the Big Dipper, was named after this valuable navigator's instrument. Early in the 20th century, the International Astronomical Union reorganized the boundaries of all the constellations and the Quadrant was eliminated, but its name persists in the name of the meteor shower. The second mystery arises from the fact that there is no known comet that follows the orbit of the meteor stream. The orbital period of the stream is about 5 years, and any comet that crosses our orbit every 5 years would surely have been discovered -- so the fate of the comet that generated the meteor stream remains a mystery.

During the next night of Jan. 4 - 5, in a rare coincidence, the planet Saturn will sail directly across the face of M1, the Crab Nebula. This nebula is the remnant of a supernova explosion that was witnessed and recorded by Chinese astronomers in the year 1054 AD. The light from the nebula is powered by a pulsar, a tiny neutron star rotating 30 times per second at its center, 6,000 light years away.

Thursday, January 2nd. Written by Alan French.

Friday, January 3rd to Sunday, January 5th. Written by George Mileski

The moon on Friday January 3rd is a waxing crescent one. Using binoculars, look in the west 30 minutes after sunset for the thin crescent moon, above it to the right is the planet Mercury. An hour or so before sunrise in the east Venus is shining with Mars to the right of Venus. Also looking further west are, Jupiter and Saturn, Saturn is very low in the horizon. Both Jupiter and Saturn are beautiful telescope objects in the evening sky.  

Tonight, Friday there is a meteor shower, it is called the quadrantid meteor shower. It appears to come from the constellation Draco. The best viewing is around midnight and at dawn, take your pick of times, looking northeast.  

Looking high in the east at night around 9pm, you will see a pentagon shaped figure of stars. This is the constellation Auriga or also called "the charioteer". There is no better way to view the Charioteer's magnificent vista than with a pair of tripod mounted binoculars. They provide just the right amount of magnification to show us bright fields with bright stars suspended on the Milky Way's faint but rich backdrop. A dark sky away from moonlight and city light pollution will give you the best views of Auriga's riches. 

Three bright star clusters in particular jumpout among the hundreds of faint stars. The first obvious one M38, lies smack in the middle of Auriga's vertically stretched pentagon. This star cluster was the 38th entry in 18th-century comet hunter Charles Messier's catalog of comet look-alikes. When this French observer looked through his telescope with poor optics at this and two other clusters, they looked to him like comets.  

In the same binocular field as M38 but 2 degrees away glows slightly brighter M36. Shift your sight 4 more degrees to the east, with M36 snugged to the edge and M37 comes into view. M37 has the faintest stars, M36 contains mostly bright stars and M38 stars run a gamut of brightnesses. If you have a telescope, M38 has a companion cluster NGC 1907.

Monday, January 6th. Written by Joseph Slomka.

Tuesday, January 7th. Written by Jonathan Cassidy.

Nights this week the nights are dark as the moon is new on Thursday. Watch near the slim lunar crescent to appear in the evening shortly after sun set. If you have a very good western horizon you might see the planet Mercury setting. It will return to the evening sky in late April and early May.

Prominent in the night sky nearly directly overhead is a fuzzy little group of stars. The name of this group is the Pleiades. They are also called the "seven sisters". There are actually several hundred members of this cluster. Most people can make out only six of the seven prominent stars of this group. In many different cultures the seventh is said to have done something to cause her to want to be unseen. In a particular story the seventh has abandoned the group altogether and has taken up with the middle star of the handle of the big dipper.

It is true that the seventh brightest of these stars is an eruptive variable. That is it can erupt and shine bright for a short time then dim to nearly invisible levels. This would have been most notable to early astronomers prior to the invention of telescopes.

On an autumn night at the RPI Hirsch Observatory several people looked at the Pleiades and counted what they could see. Like most I counted 6, one hight school student counted 8 with ease and 9 when concentrating. Check this out yourself. View this cluster from both dark and light polluted areas and see the difference.

Wednesday, January 8th. Written by Ray Bogucki.

This month, the giant planet, Jupiter, will continue to beguile observers with fascinating events visible through a small telescope. Tonight at 7:30, Jupiter's innermost moon, Io, will pass behind the third moon, Ganymede. For 20 minutes, the two satellites will appear as one. This event may be difficult to observe since Jupiter will be just rising and sitting low on the northeastern horizon. However, an hour later, at 8:30, the planet will be high enough to observe the shadow of Ganymede beginning to transit across the face of Jupiter. At 9:09, the shadow of Io will join that of Ganymede and the two will spend the next two hours crossing the planet's disk together, with faster-moving Io's shadow overtaking and passing Ganymede's shadow. Io's shadow will exit Jupiter's disk at 11:30, followed by Ganymede's at midnight. Galileo would have been transfixed at such a sight if his optics had been capable of resolving the shadows.

Three other solar system objects reach notable points in their orbits on Friday night. The Moon will be at apogee, its farthest distance from the Earth during its current orbit. Its phase will be at first quarter and it may appear a bit smaller than usual. Venus, the brilliant morning star, will reach its farthest apparent distance from the Sun at 47 degrees west and will then begin slowly to drop back toward the Sun. Mercury will be at inferior conjunction, passing between Earth and the Sun. Within two weeks it will appear in the morning sky, rising below and to the left, or east, of Venus. Mars continues to keep company with Venus, shining a little above and to the right of the brighter planet in the early morning sky. Mars will continue to grow noticeably brighter and larger in size in a telescope as Earth overtakes it. In late August, at opposition, Mars will present a magnificent sight, shining twice as bright as Jupiter and looming almost as large as the giant planet when we pass within 35 million miles, our closest approach to Mars in a hundred thousand years!

Thursday, January 9th. Written by Alan French.

The Sun set at 4:40 PM this evening. The Moon is approaching first quarter and is in the Southwest at 8:00 PM tonight. The Moon will set at 11:51 tonight and the rest of the night will be dark and moonless.

Venus is at greatest elongation at 10 PM on Friday night, but it will not be in our skies at that time. "Greatest elongation" means that Venus appears as far from the Sun as possible for this appearance in the morning sky. Tomorrow morning Venus will be 47 degrees from the Sun, and will be well above the southeastern horizon before sunrise. Look for brilliant Venus about 15 degrees above the southeastern horizon around 6:00 AM tomorrow morning. You should also notice two reddish stars to the right of Venus. The higher is the planet Mars. The other is the star Antares.

Venus is now shining at magnitude minus 4.4, making it brighter than any stars or other planets. The extreme brightness of Venus makes it fairly easy to see in the daytime sky - the trick is knowing where to look. One of the easiest ways to see Venus is the morning sky is to follow it into the daytime sky as the Sun rises. While it is still visible in the morning sky note the planet's position relative to some obvious landmark. Look for it a bit farther south a little later. Until just before 9 AM is will also be moving a bit higher above the horizon as it moves southward. After 9 AM it will gradually move back down toward the horizon. A pair of binoculars is often useful for locating Venus in the daytime sky if you have a general idea where it is. Once located in binoculars, it is often possible to pick it out with the unaided eye.

If you do not have the time to follow Venus into the daytime sky, look for the planet at 8:45 AM. It will be due south and 30 degrees above the horizon. You can measure this distance by holding a fist at arms length. The distance across the knuckles is 10 degrees, so Venus will be three times this distance above the horizon. Again, binoculars may make finding Venus a bit easier. If the skies are fairly clear, it should be obvious to the naked eye too.

Friday, January 10th to Sunday, January 12th. Written by George Mileski

On Friday the moon is at first quarter, the moon is also at apogee or 251,247 miles from earth, its furtherest distance from us. On Saturday January 11th, Mercury is at inferior conjunction, we will not be able to see it, within 10 days, it will be easy to see in the morning sky. About 11/2 hours before sunrise Venus is shining with Mars to its upper right and Antares the brightest star in Scorpius below it. 

After being difficult to find for the few months when it is close to the horizon in early evening, Ursa Major, the great bear is now reappearing in the skies shortly after sunset. She is standing on her tail. The pointer stars Merak and Dubhe, direct us to Polaris, the north star in Ursa Minor, the little bear. In between is the tail of Draco, the dragon. Above these groups of stars lies one of the most obscure constellations, Camelopardalis, the giraffe. Maybe the best way to find it is to look for a region in the northern sky that seems to contain no stars. This modern constellation's main feature is that it is long and ungainly like its namesake. 

The stars that outline this constellation are very very dim, its tough to trace out, but that doesn't mean you shouldn't try. You do need a dark site. Around it are some of the sky's best-known figures, Cepheus, Cassiopeia, Perseus, Auriga and Ursa Major. A line of four bright stars runs almost vertically down the eastern sky. Highest is Capella, in Auriga the herdsman, somewhat lower are Castor and Pollux, in Gemini the twins and just on the horizon is Regulus, in Leo the lion, becoming higher with each passing minute. Below Gemini is Cancer the crab, a famous but indistinct group of stars. Cancer is best known as the location of the beehive cluster or Praesepe. This large group of faint stars is located just above the two middle stars in Cancer. In binoculars it is sparkling, in a small telescope even better. Leo in now partly above the horizon but in an hour or so all of him will appear as will more of the constellation Hydra the water serpent.  

Monday, January 13th. Written by Joseph Slomka.

The Sun sets at 4:44 PM, with night falling at 6:24. Dawn breaks at 5:44 AM and ends with sunrise at 7:24.

As the sky darkens, Saturn is the brightest object in the East. Saturn continues its trek through Taurus. Although it passed through the famous Crab Nebula a week ago, Saturn is close enough to act as a guide. The Crab Nebula will be a degree and a half East of Saturn.

Jupiter rises before midnight and guides us to two deep sky objects &endash; star clusters. About eight and a half degrees above Jupiter is the famous Beehive Cluster, M44. This is visible as a hazy patch to the naked eye, and a star cluster in binoculars. Another binocular cluster, M 67, is seven and a half degrees below Jupiter.

Dawn finds Venus and Mars attracting attention. Both planets are equally high in the constellation Scorpius. Venus is brightest; Mars, West of Venus, is dimmer but a distinctive red color. The pair forms a nice triangle with the brightest star in Scorpius, Antares. Antares also appears red and is equal to Mars' glare.

Tuesday, January 14th. Written by Jonathan Cassidy.

We have a waxing crescent moon this evening. It is growing larger and brighter each night.

This week we have two planetary conjuctions to watch for. First watch as the moon comes close to Saturn and the horns of Tarus the Bull on Wednesday night. The Bull's horns will be the only visible stars north and south of the moon in the area with in twenty degrees of the moon. This is the longest distance between your spread out thumb and pinky on your out streached arm.

You will see the moon with saturn next to it and one star above the moon and one below Saturn.. Notice to the west the bright redish star. This is Aldebaran, the eye of the bull. This star is a red giant. It is in the late stage of its life. Aldebaran in Arabic means "the follower". Indeed this star does follow the group of stars know as the Pleiades. The color of the star indicates its temperature. Blue stars like Rigel are very hot. Yellow stars like our sun are cooler and red stars cooler yet. They have burned most of their Hydrogen fuel to other elements and are now burning those other elements to make still different elements.

Taurus is a sign on the zodiac and is thus because both the sun and moon move through this constellation. It was identified many thousands of years ago by early cultures. Modern science and civilization honors those cultures by retaining the star name and the constellation.

Wednesday, January 15th. Written by Ray Bogucki.

The ringed planet Saturn is easy to find tonight. It shines like a bright, cream-colored star just 3 degrees south, or to the right of the almost full Moon in the eastern sky at nightfall. While bright moonlight washes out faint objects such as nebulas and galaxies, planets are bright enough to observe even when they are close to the Moon.

A few hours later, after Saturn and the Moon have moved westward, Jupiter will move into the vacated spot in the eastern sky and present another in its ongoing series of double shadow transits. A few minutes after 11 p.m., the tiny dark shadow of the innermost moon. Io, will enter Jupiter's disk at the eastern limb. At half-past midnight, Ganymede will add its shadow to Io's and the two will cross Jupiter's face together until Io's shadow exits at 1:20 a.m., followed by Ganymede's at 4 a.m.

In the late evening, the brightest and most familiar constellation, Orion, is at its highest in the southern sky. Most of the stars in Orion, including the three belt stars, are hot, young, blue-white stars. An obvious exception is Betelgeuse, the orange star above the belt in Orion's shoulder. This cooler red super-giant star is possibly the largest single object that can be seen by the human eye. The diameter of Betelgeuse is considerably larger than the diameter of Earth's orbit around the Sun. Below Orion's belt in the foot of the hunter, blue-white Rigel shines at a brilliant zero magnitude. While it is not quite as bright as its near neighbor Sirius, to the south, it is only because it is 100 times farther away than Sirius. If we could bring Rigel to the distance of Sirius, it would blaze almost 2,000 times brighter than Sirius. We could easily read a newspaper at midnight with the light of such a star.

Thursday, January 16th. Written by Susan C. French.

The waxing gibbous moon will be in the constellation Gemini, the Twins, this evening and will be due south at about 9 PM. To the left of the moon you'll see two fairly bright stars, Castor and Pollux, which mark the heads of the Twins. If you hold your fist at arm's length, it will just about cover the distance between the moon and these stars. Although Castor and Pollux are called the twin stars, Pollux is actually slightly brighter than Castor. In most constellations the brightest star is called "alpha", but in Gemini Castor is the "alpha" star. Some have suggested that the brightness of either Castor or Pollux might have changed since Castor received this designation.  

The name Pollux comes from a Greek word meaning "the boxer". Pollux is a yellowish star. It is the seventeenth brightest star in the sky and lies at a distance of about 210 trillion miles.  

The name Castor means "the horseman". It is the twenty-third brightest star in the sky and lies at a distance of about 270 trillion miles. Castor is a white star. The human eye is not very good at picking out color in the pinpoint lights of the stars. See if you can notice the subtle difference between whitish Castor and golden Pollux. The various colors of stars are due to differing temperatures. If you heat steel it first glows a reddish orange, as the temperature increases the color changes to yellow, then white, and finally blue-white. Thus Castor is a hotter star than Pollux. Although Castor is hotter, Pollux looks brighter because it is a larger star and thus has a larger light-emitting surface.  

Although Castor looks like a single star to the eye it is actually a multiple star system. Amateur telescopes reveal two bright stars close together and a third faint companion farther away. Special instruments reveal that each of the three stars has an unseen companion. Thus Castor is actually a remarkable system of six stars traveling about each other in the depths of space.  

The bright components of Castor may be seen by attending one of the star parties held by the Albany Area Amateur Astronomers. At these star parties a variety of telescopes will provide you with views of many celestial sights. Star parties are free and open to the public. For a schedule send a stamped self addressed envelope to: Susan French, The Dudley Observatory, 107 Nott Terrace, Suite 201, Schenectady, New York, 12038.  

Friday, January 17th to Sunday, January 19th. Written by George Mileski

The moon on Saturday the 18th is a full moon. Jupiter is 9 degrees below the moon when it rises on Saturday. On Sunday the moon passes 4 degrees north of Jupiter. If you go outside about 45 minutes after sunset, three bright stars Altair, Vega and Deneb, shine brightly in the west. During summer the trio dominates the zenith and have come to be called "the summer triangle". The summer triangle is not a classical constellation full of mythology, but a grouping of stars called an asterism.   

Vega forms the triangle's brightest point crowning the small constellation of Lyra the harp. Vega is the brightest star in the northern half of the sky and lies 25 light-years away. Along the horizon and far to the left of blue-white Vega is the bluish Altair, shining from a mere 16 light-years away. It forms the eye of Aquila the eagle. At this time of year the mythological raptor is flying upwards, wings spread wide, as if trying to escape the cold of winter.   

Topmost in the triangle is Deneb, a star 1500 light-years away that fulfills a dual role in the sky. It marks the tail of Cygnus the swan and crowns the top of another popular asterism, the northern cross. The cross stands almost upright above the northwestern horizon after sunset, while the swan plunges head-first towards the horizon. Its worth a look before it disappears into the horizon.   

The bright star in the sky that almost everyone can identify is Sirius, in the constellation Canis Major, the greater dog. This star shines at magnitude -1.5 making it about 10 times brighter than its closest rival. Sirius is brilliant because it is close to our own sun and earth, shining across a distance of only 8.6 light-years. Sirius lies far to the south in the sky and because of this tends to shimmer and flashes different colors. Some people will jump to the conclusion that there seeing a UFO and of course all there seeing is a very bright star.   

Monday, January 20th. Written by Joseph Slomka.

Tuesday, January 21st. Written by Jonathan Cassidy.

Full moon at the end of this week, thus we have bright nights. Not as many stars are visible at night this week than there were two weeks ago. Thus we need to look for the bright stars that serve as sign posts for this season.

We have the "winter circle" of bright stars to observe now. It is a rather lopsided circle, prehaps a little oblong, maybe like that pointy ended ball making such prominent appearance in sports since September.

We can name these stars and use them to point to other objects and star clusters. Lowest & brightest in the sky is Sirius, to the upper left in a circular fashion is Procyon, then Pollux and cimmer Castor, at the top is Capella, going down the other side is Aldebaran the reddest of the circle, Rigel the bluest is last and back to Sirius.

Notice that inside the circle is a star more red than Aldebaran. This is Betelgeuse. There are two more objects of note that are quire bright. Saturn is between Betelgeuse and Capella. Jupiter is outside the circle, to the east, and out shines all the bright stars we have mentioned.

All the stars appear in this same configuration each year with no noticable change. The planets Jupiter and Saturn move considerably from year to year. They will not be back to this area of the sky next year.

Wednesday, January 22nd. Written by Ray Bogucki.

For the next few days, early risers can catch a glimpse of all five bright planets. Venus rises about 4 a.m., outshining everything else except the Moon in the night sky. Venus is preceded by Mars, shining at first magnitude above and to the right of Venus. Be careful to distinguish Mars from its traditional rival, the red supergiant star, Antares, in the constellation Scorpius. Antares shines just a few degrees below Mars with about the same color and brightness. In fact, the name "Antares" literally means "rival of Mars". In the coming months, Mars will become steadily brighter and this summer, it will far outstrip its rival.

Jupiter dominates the southern sky, while Saturn is preparing to set, just above the western horizon. About an hour after the western horizon has risen to block Saturn, the dropping eastern horizon exposes the fifth planet, Mercury, rising well below and to the left of Venus just as the first hint of morning twilight tints the morning sky.

Only two easily viewable events remain in the current series of double shadow transits on Jupiter. The next one occurs Friday evening when the moon Io's shadow begins crossing the disk of Jupiter about 7:30. It will be joined by the shadow of Europa at 8:42. The two will transit together for an hour until Io's shadow exits, followed two hours later by Europa's shadow. This event is visible in a small telescope.

If you observe from a dark location, scan the western horizon as the last vestige of evening twilight darkens around 7 p.m. In the absence of bright moonlight, you may catch a glimpse of the large, faint, ghostly white pyramid of light called Zodiacal Light rising from the western horizon just to the left of the great square of Pegasus. At this time of the year, the plane of the ecliptic rises at a steep angle from the western horizon, making it easier to see the faint reflection of sunlight from the countless tiny dust particles that clutter the inner solar system. The dust particles are assumed to be produced by the endless grinding collisions in the asteroid belt beyond Mars, from where they slowly spiral into the Sun along the plane of the ecliptic.

Thursday, January 23rd. Written by Peter Jennes.

Friday, January 24th to Sunday, January 26th. Written by George Mileski

The moon is at last quarter on Saturday the 25th. If you get up one hour before sunrise on Friday the 24th, you will see a planet lineup of Mercury, which is very low on the horizon with Venus Mars and Jupiter marking the sky. The planets Venus and Mars are near the summer constellation Scorpius. Early in the evening sky, look with binoculars, for the comet Neat, it is in the constellation Pisces, just below Pegasus. For location maps of this object, check the "SkyandTelescope.com" or "Heavens-Above.com" website.  

On a dark and winter night when there's no moon and you're standing beneath a country sky, look to the southeast for the elusive constellation Monoceros, the unicorn. Monoceros lies in the midst of a triangle, by the two dog stars, Sirius and Procyon, and the bright red star Betelgeuse in Orion. When we look in that area of sky, all we see are a few faint scattered stars. There are many legends about unicorns, but most people recall that they can only be lured into captivity by the gentleness of a young girl. Another ancient legend says that a horn of a unicorn renders poison harmless.  

Like all unicorns, Monoceros has its own magic. A faint narrow portion of the winter milky way runs behind the constellation, and thus it contains a number of fine open star clusters. When looking at Monoceros, be sure to use your binoculars so you can take in more of what the constellation has to offer. In 1772, Charles Messier noted a smudge of light located a little more than a third of the way from Sirius to Procyon. He assigned the number 50 to this little smudge, which turned out to be a cluster of several hundred stars. M50 as its generally called lies about 3000 light-years from earth.

This cluster is easy to find with binoculars. Another good binocular target is NGC2244. It consists of a 6th magnitude star with fainter stars clustered around it. Also surrounding NGC2244 is a remnant of the cloud from which these stars formed, which we call the Rosette Nebula. NGC2244 is about a third of an imaginary line from Betelgeuse to Procyon.   

Monday, January 27th. Written by Joseph Slomka.

The Sun sets at 5:02 PM, with night falling at 6:40. Dawn breaks at 5:27 AM with the Sun rising at 7:14.

By Sunset, Saturn is already high in the East. It is the second brightest object, after the star Sirius, which is lower in the sky. Saturn is one of the greatest showpieces of the sky. The rings are open to its maximum. Saturn has company. It lies within a binocular field of M-1, the Crab Nebula. In the year 1054, a star exploded and shone in daylight. The Crab Nebula, an expanding debris cloud, is all that is left.

Before sunrise in the East, the thin crescent Moon joins the fatter crescent of Venus, just above. Dimmer Mars forms a loose triangle with Venus and the Moon. While Mercury hugs the horizon; it too is a crescent, as seen in telescopes.

By midnight, Jupiter joins the sky, lower in the East. Jupiter, too has company. Its position is Cancer, the Crab, the home to two star clusters. Both are within seven degrees, or slightly larger than one binocular field.

Tuesday, January 28th. Written by Jonathan Cassidy.

Waning crescent moon this week leaves us with dark skies for observing. Watch for a close alignment of the waning crescent moon and Venus on Tuesday morning January 28th. You will see this one hour before sunrise.

The big dipper is now rising in the east once the sky is fully dark. For those people with telescopes the galaxies M81 & M82 are in very good position to observe from now till March.

For those who enjoy naked eye observatoin there is a fine double cluster of stars to be seen near the top of the sky. Observe in a place away from lights. Let your eyes adapt to the dark.

To find this group the familiar "W" of the constellation Cassiopia. This is nearly overhead Then count from west to east the stars 1, 2, 3, 4. Look at the line from 3 to 4 and extend that line out to the east by one and one half times the distance between the stars. Here is the double cluster of Perseus. You might have to use averted vision to see it. It will appear as a patch of dim light over an area a little smaller than the full moon. There are actually two clusters here but the naked dyd image is of one patch of brightness.

Wednesday, January 29th. Written by Ray Bogucki.

When the night becomes fully dark, around 7 p.m., you can find the constellation Gemini, the Twins, well up in the eastern sky halfway between the planets Saturn and Jupiter. Gemini is easily recognized by its two bright stars, Castor and Pollux, named after the Twins of Greek mythology. The stars are about 5 degrees, or three finger widths, apart with Pollux, the brighter of the two, lying east of, or below Castor. The two stars mark the heads of the twins, while their arms, torsos and legs are delineated by lines of stars stretching toward Orion.

As well as being the brighter of the two stars, Pollux is distinctly more yellow, while Castor is a classic white star. It is interesting that Ptolemy, a keen-eyed observer in the golden age of Greece, listed Castor as the brighter of the two. This ranking was reinforced for a couple of thousand years by astronomers from many countries. As recently as 1700, John Flamsteed, the first British Royal Astronomer, ranked Castor as first magnitude with Pollux as second magnitude. Tonight, your eye will tell you that Pollux is clearly brighter. It appears that one of the stars has changed magnitude.

In a telescope, Castor is seen to be an excellent close double star with a separation of 3 arc-seconds. In 1803, after observing Castor for years, Sir William Herschel declared that this was a true binary pair of stars, revolving around their common center of gravity. It was the first binary pair to be recognized as such. The two stars are about 9 billion miles apart and have an orbital period of about 420 years. Spectroscopic studies show that the two stars, Castor A and Castor B, are each themselves close pairs, too close to be separated, even in large telescopes. The stars forming Castor A are twice the size of the Sun and orbit each other in 9 days at a distance of 4 million miles. This is so close that their outer atmospheres must be in contact! Castor B's pair are only 3 million miles apart with an orbital period of 3 days. Finally, a faint red star, Castor C, is an even closer double that orbits the entire system. Castor is thus a six-star, complex stellar family. Observers on a planet in this system would watch a fascinating celestial dance of the six suns.

Thursday, January 30th. Written by Peter Jennes.

Friday, January 31st to Sunday, February 2nd. Written by George Mileski

On Saturday February 1st, there is a new moon. On Sunday 45 minutes after sunset, check out the young crescent moon, and use binoculars to find it. On Saturday looking east, one hour before sunrise the planets Mercury, Venus, Mars and Jupiter are lined up in the early morning sky. Jupiter is at opposition on the night of February 1st, it shines at -2.6 magnitude and is up all night from sunset to sunrise. 

You don't need a telescope to explore the wonders of deep space. All you have to do is lie back, with your star charts and look up. Humans have watched the stars overhead for thousands of years, but they didnot understand what the tiny lights signify. You can see over 40 deep-sky objects without a telescope, a handful of those are visible even from a city. I am not going to cover 40 objects here, but a good start is the "Pleiades star cluster". Its tiny dipper shape is easy to pick out on these chilly winter evenings. A few degrees south of the Pleiades lies another star cluster, the Hyades. Ruddy Aldebaran appears to be the brightest member of this grouping, but in fact it is a foreground star, so it is not a member of the Hyades cluster. 

From our latitude only one gas cloud or nebula is bright enough to pierce through the light pollution. Thats the Orion Nebula or M42. It can be spotted as the fuzzy middle star of Orion's sword, which hangs down from the three belt stars. Also look at all the bright stars in that area, Sirius, Rigel, Betelgeuse, Capella and others, they form a huge celestial "G". You can also use your naked-eye skills to follow the brightness changes of some of the brighter variable stars. Some like Algol in Perseus vary in brightness because they are eclipsed by a less-luminous companion. Algol normally shines at magnitude 2.1, but during a 10 hour period it fades 1.3 magnitudes and then returns to normal, then 2.9 days later it fades again. 

This was just a preview of some of the objects in the winter sky that can be seen naked-eye. 

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