Skywatch September 2002

These scripts are written by members of the Albany Area Amateur Astronomers and read by the staff of the Dudley Observatory. All scripts are copyright and may not be reproduced without permission of the writer and the Dudley Observatory. Scripts are published to the web in the week following their recording. Daily scripts may be heard by calling 518-382-7584 after 5pm.

 

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

Monday, September 2nd. Written by Joseph Slomka.

Tuesday, September 3rd. Written by Jonathan Cassidy.

Nights this week the nights are dark as we are without the moon. The new moon occurs on Thursday September 6th. This is a good week to go out with binoculars or just your eyes and look at our own galaxy, the Milky Way. It can be seen now after 9 PM from a dark sky location.

To find it look directly over head and see the three brightest stars: Vega, Deneb and Altair. These three form the Summer Triangle. Vega is easily the brightest. Deneb is nearest Vega and Altair is to the south. Imagin a line drawn from Denab toward Altair but missing it to the east by just a bit. Extend this line to the north west and find the constellation Cassiopia, the familiar "W". Extend to the south and you will see the Teapot asterism found in the constellation Sagitarius, near the horizon.

This is the line of our home galaxy the Milky Way, looking from the inside toward the center near Sagitarius. Knowing this you might now notice that stars seem more plentiful along this line. This is true as the Milky Way is more dense with stars when looking along the plane of the galaxy.

Look toward the Big Dipper or toward the Great Square of Pegasus, now rising in the East, and you will see fewer individual stars. This is looking out of the Milky Way perpendicular to the plane, the short dimension.

Wednesday, September 4th. Written by Ray Bogucki.

This week presents an opportunity to take notice of some of the dynamic aspects of the clockwork motions of our solar system. As we approach the autumnal equinox on Sept. 22, we might examine the spectacular differences in the Sun's apparent motions during solstices and equinoxes. Careful observers will recall that during the one-month period, from early June to early July, centered on the summer solstice on June 21, the Sun's daily path through the sky varied very little. Each morning the Sun rose about 5:30 at a point on the horizon well north of true east, circled high into the southern sky, reaching an altitude of about 70 degrees at noon, and set about 8:30 at a point well north of true west.

During this period we experienced 15 hours of sunlight with very short shadows at noon. Beleaguered astonomers had to wait till 10:30 for the end of evening twilight only to be met with the start of morning twilight a scant 5 hours later.

For the month starting now and encompassing the autumnal equinox, the Sun's behavior is dramatically different. Each day the Sun will rise more than a minute later and set almost two minutes earlier. The points of sunrise and sunset will move rapidly southward along the eastern and western horizons, and the altitude of the Sun at noon will drop noticeably each day. The overall effect of these changes is that the elevation of the noontime Sun will drop almost 12 degrees, and we will lose an hour and a quarter of sunlight, although on the positive side, astronomers will gain that amount of added observing time. The lengthening shadows at noon announce that the shallower angle of sunlight will transport less heat to each square foot of ground. This effect, coupled with the shorter hours of sunlight, will cause a noticeable cooling as we head toward fall and winter. All of these effects result from the 23-degree tilt of the Earth's rotational axis from the perpendicular to our orbital plane. Thanks to this tilt, we can enjoy the glorious procession of the seasons.

Thursday, September 5th. Written by Alan French.

An attentive sky watcher is likely to catch a satellite or two crossing the sky near dusk or dawn on any clear night. We see satellites because they are high above us and still in the sunlight. Tonight we have a chance to see an interesting "satellite" emerge from the Earth's shadow high overhead. The Okean O Rocket will come out of the Earth's shadow high in the west-southwest just after 9:57 PM tonight. Look to the south of the constellation Hercules. If you are unfamiliar with Hercules, simply look high in the southwest.

The Okean O Rocket is somewhat eye catching since it is a tumbling rocket booster. As it tumbles it rapidly changes in brightness, and the rapid blinking attracts your attention. This satellite will be highest at 9:57:35 PM, and then will move through the constellation Hercules toward the north-northwest. If you missed it when it first appeared, watch for it to pass through the bowl of the Big Dipper. It will vanish below the north-northwestern horizon at 10:02 PM.

Early risers will get a change to see the International Space Station pass over our area tomorrow morning. The ISS will move out of the Earth's shadow well above the southwestern horizon just before 5:07 AM tomorrow morning. It will be highest just after 5:08 AM when it will be 65 degrees above the southeastern horizon. Simply look for a bright star very high above the horizon moving from southwest to east-northeast. The ISS will vanish below the east-northeastern horizon at 5:11:30 AM.

The Albany Area Amateur Astronomers will be hosting two public Star Watches this weekend. At Star Watches a variety of telescopes are set up to show guests some celestial showpieces. These events are free and open to all ages.

On Friday night a Star Watch will be held at the George Landis Arboretum in Esperance beginning at 8:30 PM. Look for the Arboretum sign on Route 20 just after crossing the Schoharie Creek into Esperance. Follow the signs up the hill to the Arboretum. Continue past the parking area and farmhouse to the top of the hill. Take a right at the top of the hill into the Meeting House field.

On Saturday night a Star Watch will be held in Indian Meadows Park in Glenville also beginning at 8:30 PM. Indian Meadows Park is off of Droms Road. Once in the park bear left at the fork in the road past the first building. Star Watches are canceled if the skies are mostly cloudy. For further information call 374-8460.

Friday, September 6th to Sunday, September 8th. Written by George Mileski

On Friday the moon is new at exactly 11:10pm. On Sunday in the west you will find Venus with the star Spica to its right. Spica is the brightest star in the constellation Virgo, the virgin. Look 30 minutes after sunset. Also to the far right of Venus is the waxing crescent moon. The planet Mercury is below the moon, a little to the left. Mercury is very hard to see, so don't be surprised if you can't find it. About 11/2 hours before sunrise look to the east and you will find Jupiter about 1 degree south of M44 or the Beehive cluster in the constellation Cancer. 

Saturn is very high in the ESE, its in the constellation Taurus, the bull. On Friday, September 6th, 35 minutes before sunrise look east for the old crescent moon with the star Regulus to the upper right and below it is the planet Mars, a little to the left of Regulus. You will need binoculars for this. 

September and October is the time of the year to see a phenomena called zodiacal light. It is caused by microscopic dust particles in the sky. The zodiacal light is a faint glow in the sky, roughly triangular, along and near the ecliptic. At its brightest and under good dark skies it is about as bright as portions of the Milky Way. It is the faint reflection of sunlight from dust grains, most of which lie near the plane of the ecliptic in the solar system. It is brightest at small angular distances from the sun, and fades off as our gaze turns away from the sun. 

The light from the glow is best seen just before sunrise. This is sometimes called a "false dawn". Zodiacal light is most easily visible at seasons when the ecliptic is most nearly perpendicular to the horizon, favoring after-sunset viewing in March and April and before-dawn viewing in September and October. The next two weeks are particularly good for viewing this.   

Monday, September 9th. Written by Joseph Slomka.

The Sun sets tonight at 7:16 with night falling at 8:54. Dawn breaks at 4:52 AM and ends with sunrise at 6:29.

As the sky darkens, Venus shines brightly about twelve degrees above the horizon. If you observe Venus with a telescope, you see a thin crescent, about a third illuminated. The Moon appears to Venus' West; it is also a crescent about half as thin as the Moon. If you enjoy a flat vista, Mercury hovers above the horizon to the Moon's lower right.

Predawn hours contain some interesting sights. Saturn is the highest. It appears at the tip of Taurus' lower horn. If you use a telescope, Saturn shares the same finder view with the famous "Crab Nebula", only four degrees away.

Jupiter appears midway between horizon and Saturn. Its four famous moons are visible in binoculars. However, there is the additional attraction of the "Beehive Cluster." The Beehive, also known as M-44, is also a great binocular object. This morning, both share the same binocular field. The early riser will be well rewarded.

This Saturday, the Albany Area Astronomers held their monthly public star party. Shortly after nightfall, a dim glow spanned across the northern horizon. The glow became brighter and turned into "Aurorae" or "Northern Lights." Bright streaks reached overhead and entertained the audience for about an hour. Aurorae are caused by the Sun. It constantly emits a stream of particles. However, it sometimes emits a large burst in the direction of Earth. If the burst is large or energetic enough, it impacts the Earth's upper atmosphere and causes layers to fluoresce. This is what we see as the "Northern Lights." If the outbursts are really energetic, colors and dancing patterns can be seen. These events are not just pretty sights. Radio and satellite communications can be disturbed and power grids can be shut down. There are no seasons or times. Northern Lights appear at random and not every solar outburst causes Aurorae. It pays to periodically look north on dark nights. You may witness the beginning of a beautiful show.

Tuesday, September 10th. Written by Jonathan Cassidy.

The crescent moon tonight is above bright Venus, near the horison. To the moon's left is the bbright star, Antares. Antares is the heart of the figure in the constellation Scorpius.

Antares is one of several bright stars that help us know our way around the night sky. Though these bright stars change season to season there are not so many of them and you can remember them if you hear them enough.

In this changing of seasons time we see the summer stars slipping away and the fall stars coming up in the east. Antares is a summer star we start to look for it in late spring.

Low in the east at around 9:30 is the bright star Formalhaut of the constellation Piscis Austrinus. Since this star is so low to the horizon we will see it for only a short time in late summer and early autumn. It marks for us the change of seasons. By the time Fomalhaut is due south we will be able to see the Pleiades rising in the east. After the Pleiades comes Aldebaran in Tarus the Bull then Orion.

Wednesday, September 11th. Written by Ray Bogucki.

Because the Sun is approaching the autumnal equinox, it now lies close to the celestial equator. At new Moon last Saturday, the Moon was positioned near the Sun and therefore also close to the celestial equator. For the two weeks following new Moon, the Moon will travel the southern branch of the ecliptic which lies south of, or below, the celestial equator. The Sun will require a half year to cover this same path. Tomorrow evening, near first quarter, the Moon will be in the constellation, Scorpius, approaching the red supergiant star, Antares, which lies 26 degrees below the celestial equator and together they will just skim the treetops about 22 degrees above the horizon. On Sept. 21, this month's full Moon, known as the "Harvest Moon", will be opposite the Sun and therefore back near the celestial equator, reaching its highest elevation, about 48 degrees above the southern horizon, about midnight. A week later, at last quarter, the Moon will lie very close to Saturn in the dark early morning sky at the northernmost reach of the ecliptic. Near sunrise, the pair will have climbed close to the zenith at 70 degrees above the southern horizon.

During the coming week, several reasons might entice an observer to go out early, about 4 a.m., an hour before morning twilight begins. The crescent Moon will already have set so the skies will be dark. Both Saturn and Jupiter are now easily observed. Jupiter, low in the east, is currently close to the bright open star cluster, M 44, known as the "Beehive". Saturn is high in the southeastern sky and near quadrature so the angle of the Sun's light causes a definite shadow of Saturn's disk on the widely tipped rings, generating an excellent 3-dimensional aspect to the image.

Finally, the famous prototypical red supergiant variable star, Mira, in Cetus the Whale, is near its maximum brightness for this cycle, easily visible with the unaided eye as a moderately bright star. But look soon, because this giant star, with a roughly 11-month cycle and diameter larger than Mars' orbit, will fade in a few weeks back to naked-eye invisibility until next summer.

Thursday, September 12th. Written by Peter Jennes.

Friday, September 13th to Sunday, September 15th. Written by George Mileski

Monday, September 16th. Written by Joseph Slomka.

The Sun sets at 7:03 PM, with night falling at 8:40 PM. Dawn begins at 5:01 AM, with sunrise taking place at 6:37.

As the sky darkens only Venus remains visible. It is quite low in the sky, only eleven degrees up, and may be hidden by trees, hills or buildings. Venus is nearing greatest brilliance, but its position may hinder the view.

The Moon is just rising in the southeast and will remain up for most of the night. As a result, most deep sky objects will be lost in the glare.

The first hints of dawn reveal two bright planets attracting our attention. Saturn is highest in the East. It lies within a single binocular view of the first object in Messier's List, the famous Crab Nebula. Most binoculars will not show this nebula, but almost any telescope will.

Jupiter lies lower in the East. It too is a great binocular object. Its four famous moons are alone worthy of extended observation. However, Jupiter also lies about three degrees from the famous Beehive star Cluster. Unlike the Crab Nebula, the Beehive is visible to the naked eye in dark locations. Binoculars reveal the hazy patch to be a true swarm of stars, resembling its name.

Cancer is famous for galactic clusters. Although visible to the naked eye on moonless nights, M44, also known as "Praesepe," "Beehive" or "Manger" requires binoculars to fully appreciate its beauty. Indeed, the stars do resemble a swarm; about 200 stars are members of this group. The "Beehive" is about 40 light years in diameter, 525 light years distant and occupies about 1 degree of sky. Ancient cultures were well aware of this group. The Greeks used it as a weather forecasting tool; high altitude haze would obscure this nebula, a prediction for stormy weather. The ancients called the Praesepe a "little cloud," since they could not see individual stars. Leonardo Da Vinci was the first to train a telescope on this "cloud" and realized its true nature.

Tuesday, September 17th. Written by Jonathan Cassidy.

Full moon this week so the night sky is not as dark as two weeks ago. We can see three bright stars over head forming a large triangle. These stars are: Vega, Deneb and Altair. Together they form the "summer triangle".

Deep in cities under light pollution these three will stand out along with maybe a dozen more stars. Away to the north east of the summer triangle you will see the familiar "W" of the constellation Cassiopia. Now we see the "W" on its side. Later we when it rises earlier we will see it upside down.. It is only in the spring when it is on the horizon that we see it standing up as a proper "W" would do.

Toward the north west the birght stars of the bowl of the Big Dipper show that it is lowering toward the horizon, empty now. According to mythology it is lowering down to refill over the winter. In the spring it will rise again full ready to water the earth with spring rains.

Follow the arc of the handle of the Big Dipper to find the bright star Arcturus low down in the west. Arcturus has been with us since spring and will return next year when the snow melts.

Wednesday, September 18th. Written by Ray Bogucki.

Tonight, the waxing gibbous Moon will act as a guide in finding the distant gas giant Uranus. As darkness falls, the Moon will be passing about 4 degrees below, or south, of Uranus. If you place the top limb of the Moon at the bottom of a binocular field, Uranus should be located at the top right of the field. By good fortune, Uranus is currently quite close to the fifth-magnitude star, Mu Capricorni, a bit brighter than Uranus. This close pair should be apparent, with Uranus shining steadily as a pale blue-green dot, while its brighter companion twinkles in typical star-like fashion. Uranus was at opposition, or its closest approach to Earth last month, so its disk diameter of 3.7 arc-seconds is about as large as it gets.

While this is comparatively small, it is actually a little larger than the current disk size of our nearest outer planet, Mars. The red planet is just emerging from behind the Sun and thus is at its farthest distance from Earth for this orbit. By coincidence it is also at aphelion, its farthest distance from the Sun in its elliptical orbit, which adds several million extra miles to its distance from Earth. Its current distance of about 245 million miles makes Mars appear as small and as faint as it ever gets. It is now climbing into the morning sky, rising about an hour before the Sun. Over the next year, we will gradually overtake Mars and watch it slowly grow larger and brighter. In late August next year, we will pass between the Sun and Mars, placing Mars at opposition, its closest approach to Earth. Because Mars will be at perihelion, its closest approach to the Sun, it will be exceptionally close to the Earth, less than 35 million miles, closer than it has been for 73,000 years. Mars will shine brighter than Jupiter and its diameter will have grown to 24 arc-seconds, considerably larger than the current disk size of Saturn. Astronomers will seize this unparallelled opportunity to study the surface features of our mysterious red neighbor.

Thursday, September 19th. Written by Alan French.

The Moon is now approaching Full and rose at 5:40 PM this evening - about 20 minutes before the Sun set. Look for the Moon low toward the east-southeastern horizon just after the sky starts to darken. The Moon will be Full early Saturday morning. The Full Moon this month is the Harvest Moon, which is the Full Moon closest to the autumnal equinox. For us, autumn begins this year at 12:55 Monday morning, September 22.

When the Moon is near Full it is a very pretty sight even to the naked eye. Sometimes when it is low in the sky it may appear orange or yellowish. When it is low in the sky, just above the horizon, the Moon often looks unusually large. Since the Moon is actually a little farther away when it is down near the horizon, this appearance is actually an illusion. People often believe it looks larger on the horizon because there are objects to compare it to, yet the illusion persists even against an uncluttered ocean or desert horizon. Neither is it due to atmospheric effects - the atmosphere can only compress the vertical height of the Moon and can not make it appear larger. The illusion is not completely understood, but seems to be partially related to looking forward toward the horizon instead of looking upward to the dome of the sky. Constellations also appear larger when the are near the horizon.

A pair of binoculars can reveal quite a bit of detail on the Moon, and the full Moon allows the best views ot the lunar rays. After turning your binoculars toward the Moon, look for a large, round bright patch. This is the crater Tyco, and you will see bright rays radiating out away from the crater. Tyco was formed when an asteroid hit the Moon, and the lighter colored rays are made up of material blasted out of the crater. Dirt on the Moon's surface gets darker the longer it is exposed to solar radiation, so the younger material forming the rays is lighter than the older background material. These rays are best seen near Full moon, and disappear as the Moon moves past full. Some of the rays from Tyco stretch across one-third of the Moon's face. Look around and see if you can find other craters surrounded by rays. Rays show that a crater is relatively young and recent. Tyco is about 500 million years old. The Moon itself was formed about 3 billion years ago, probably when a Mars sized object struct our Earth.

Friday, September 20th to Sunday, September 22nd. Written by George Mileski

On Friday the moon is almost full in the constellation Aquarius. On Saturday we have a full harvest moon, its called a harvest moon because it raises shortly after sunset and with its light it extends the day for farmers to bring in there crops. Venus shines brightly in the west even though its very low on the horizon. Venus is a magnitude -4.5 at this time, it will be its brightest on the 26th at magnitude -4.6. Venus is about 40 degrees west of the sun. 

In the morning sky Mars is very low on the horizon, it is about as dim as it gets. Jumping ahead to next August it will be as bright as it ever gets, it should be quite a sight. Mars lies about 15 degrees below the star Regulus, a little to the left of it. Jupiter rises about 2:30am, so by dawn its getting quite high in the sky, its in the constellation Cancer. Saturn rises about 11:15pm and is high in the N.E. in the constellation Taurus. 

If you can get up around 5:00am, there are plenty of winter constellations to look at, such as Orion and its famous nebula M42. The constellations of Auriga, Gemini, Canis Minor or "the lesser dog" and Canis Major or "the great dog". Cancer, with Saturn in it, is not to far from the Beehive cluster M44. Just think, all this is available without freezing your hands and feet.

In the early nighttime skies in the east, there is a small constellation called Sagitta, the arrow. None of these stars is brighter than magnitude 4.4. Still Sagitta is surprisingly easy to pick out because its stars really resemble an arrow. If you look closely through a pair of binoculars at the Sagitta region, you'll see a fuzzy patch of light that appears to glow with the light of many individual stars. This is the globular cluster M71, a collection of several hundred thousand stars. M71 is a relatively easy object for binoculars on a moonless night. Sagitta is located north of Aquila the eagle. Sagitta is the third smallest of all 88 constellations. Only the Southern Cross and Equuleus, the "little horse" are smaller.   

Monday, September 23rd. Written by Joseph Slomka.

The Sun sets at 6:51 PM, with night falling at 8:26. The waxing gibbous Moon rises at 8:04 PM and remains up the rest of the night. Dawn breaks at 5:10 tomorrow morning, and ends with sunrise at 6:45.

As the sky darkens, Venus is the only visible planet. It lies low above the horizon, preparing to temporarily depart our skies. Those observers blessed with a flat horizon can find Venus nearing maximum brilliance, and its thinnest crescent.

Dawn skies are easier for the observer. Both Saturn and Jupiter are up after midnight and are best placed for early risers. Saturn is highest in the East, followed by Jupiter, about midway between Saturn and the horizon. Mars peeks above the horizon shortly before sunrise, but hills and trees may hide it.

If you look straight up at the Northern Sky, you will see Cepheus, a constellation shaped like home plate. One of its stars, Delta, proves very interesting. This star varies in brightness precisely once every five days, eight and three-quarters hours. However, these stars do not vary very much in brightness. They are generally supergiant stars about 25 times the Sun's size. Such stars, called cepheids, are very important for they are "measuring sticks of the universe." Astronomers have discovered that the longer the period, the more luminous a star is. Luminosity means the actual brightness of a star. Thus, if we know how luminous a star really is, and how bright it is in our telescopes, we estimate how far away the star is. Seven hundred such cepheids have been discovered, and now astronomers have a good idea how far away such objects as the Andromeda Galaxy really are. Why do these stars pulsate? No one knows. Some think that it is a battle between the nuclear fires trying to expand, and gravity trying to hold the fires in. But such theories do not explain the precise timing of these changes. Consult a star chart and follow Delta Cephei changes for a week and see for yourself.

Tuesday, September 24th. Written by Jonathan Cassidy.

With the regular baseball season coming to an end we have rising now a celestial version of baseball. In the east now half way up the sky when it is full dark is a large square or diamond of stars.

If you find the brightest star of the night, Vega, directly overhead and go half way to the eastern horizon you will find it. The corners are noted by stars of similar brightness. There will seem to be not much inside the square, except for one star.

The corner star nearer to Vega semms to have a smaller star behind it, as do the stars most to the north and south. Yet the star nearest the horizon does not have a close by star.

Look with your baseball eyes and see that there is a catcher behind home plate near Vega. To the north and south first and third bases have coaches near by but second base has none. Second base seems alone and later in the season we might see that there are stars representing out fielders way out.

This is a way to remember stars and the patterns they make. Ancient peoples saw flying horses, royalty and monsters. In the same way we can make up our own images and mythology to help us remember.

Wednesday, September 25th. Written by Ray Bogucki.

At nightfall the bright star Vega shines high overhead, almost at the zenith. With a magnitude of zero, Vega is the fifth brightest star anywhere in the night sky. While it is a magnificent, large white star with 3 times the diameter, twice the surface temperature and 50 times the luminosity of the Sun, its brightness is due primarily to its proximity. Our Sun and its attendant planets are moving through the depths of space in a direction toward Vega at 12 miles per second. At this speed, it would take almost a half-million years to cover the relatively short, 25 light-year distance that separates us.

Another interesting aspect of Vega's position in the sky follows from Earth's 26,000-year cycle of precession around the 23.5 degree tilt in our axis, which causes the point of true north to trace a 47-degree circle in the sky once each cycle. One can envision this circle by starting at Polaris, the current marker for the north polar axis, and tracing a semicircle to Vega and thence back to Polaris. In 12,000 years, the projected axis will be just 4 and a half degrees from Vega, which will then be the rough locator for north. In that era, observers at this location will be able to see many of the southern constellations that are now blocked from our view by the southern horizon.

Lying just to the southeast of Vega is a group of four, third-magnitude stars that forms an almost perfect parallellogram. This group was seen by ancient astronomers as a musical instrument known as a lyre, which gave the name Lyra to the constellation. The star in the parallellogram nearest to Vega is designated as Zeta Lyrae. Epsilon, a sixth star just to the northeast of Vega, forms a neat equilateral triangle with Vega and Zeta. To the average eye, Epsilon appears as a single star, and, in binoculars, as a wide double star with about a 200 arc-second separation. Careful inspection with a moderate-sized telescope reveals that each of the stars in the wide double is itself a very close double, each with about a 2 arc-second separation. This famous double-double star was discovered by William Herschel over 200 years ago. Next Wednesday's line will discuss several other fascinating objects in this small, but important, constellation.

Thursday, September 26th. Written by Alan French.

Tonight Venus is at greatest brilliancy and is visible in the evening sky just after sunset. (If you are calling much after 7 PM, you missed it - but take heart, it will look essentially the same tomorrow night.)

The Sun sets tonight at 6:46 PM. At sunset Venus is only a bit over eight degrees above the southwestern horizon (for reference, if you hold a fist at arms length the distance across the knuckles is ten degrees). Because Venus is so low in the sky, you will need a very low, obstruction free horizon view to the southwest. You will also need to look for Venus right after sunset, because Venus will set at 7:44. If youdo have a clear and cloud free view, you will see Venus fairly close to the horizon at 7 PM. The southwestern sky will still be fairly bright, but bright Venus should still be easy to spot. As the sky darkens Venus will appear even more brilliant.

If you have binoculars or a small telescope try looking at Venus. Venus is covered by a thick and uniform appearing atmosphere, so there are no details to see through the telescope. However, Venus goes through phases like our Moon because it is closer to the Sun than we are. Right now Venus is a fat crescent, and a careful look with some optical aid should reveal the phase. You may have to be patient to catch a glimpse of the crescent - when planets are close to the horizon we look through a thick blanket of atmosphere, and this can cause the view to shift and shimmer. If you wait for a while you should catch a steady moment when the crescent phase of Venus is obvious.

When looking at Venus you may notice that it shows various colors. This is because the thick atmosphere down near the horizon also acts like a giant prism, breaking white light up into its component colors.

If you are up in the early moring hours you can catch another bright planet. Jupiter is just above the eastern horizon around 5 AM in the morning. Tomorrow morning you will also find the Moon fairly high in the south at this time.

Friday, September 27th to Sunday, September 29th. Written by George Mileski

The moon is a waning gibbous one on Friday. On Sunday the moon is at last quarter, it will be above and to the left of the planet Saturn, Saturn is high in the S.E. sky. In the west, Venus is very low on the horizon. Seen through a telescope Venus is only about 1/4 of the way full. It is as bright as its going to get at this time. In the morning sky about an hour before sunrise, look for Mars just above the horizon, It is going to be quite low with the star Regulus 20 degrees above it, a little to the right. Jupiter is in the constellation Cancer, about 4 degrees from the beehive open cluster. 

When you look toward the southern sky, you'll find it relatively empty of stars and for good reason. When you gaze southward on autumn evenings you are looking away from the star-rich disk of the Milky Way and out towards intergalactic space. There is a single bright star in the southern sky in autumn, its called Fomalhaut and it resides in the constellation "Piscis Austrinus or "the southern fish". Fomalhaut is sometimes called "the lonely one" or "the solitary one". It makes a rather low arc across the southern sky during the course of the night, but you'll have no trouble identifying it in an expanse of sky devoid of other bright stars. 

Now tune your eyes to faint stars again to see another constellation in the southern sky. Look for the constellation Aquarius, the water carrier, located above Piscis Austrinus in the south. This constellation is large and fairly difficult to trace, but it has an identifiable asterism, a compact y-shaped grouping of stars called the "water jar". If the sky is reasonably dark, you can see a faint stream of stars zigzagging from the water jar toward Piscis Austrinus. These stars represent water flowing into the open mouth of the southern fish. 

Monday, September 30th. Written by Joseph Slomka.

The Sun sets tonight at 6:38, with night falling at 8:13. Dawn breaks at 5:18 AM, and ends with sunrise at 6:52.

This past week we experienced the rains of Hurricane Isadore. For centuries, people thought that weather only existed on Earth. Now we know that there is all kinds of weather in most of the Solar System.

The Sun is a raging ball of hydrogen gas, which is fusing into helium and other elements. However, the Sun's output is not steady. The Sun goes through an eleven year period in which the number of sunspots vary. The exact mechanism is still not thoroughly understood, but as the number of spots increase, so do the number and degree of solar storms. These storms spew vast quantities of particles in all directions. If Earth gets in the way of such a storm, its atmosphere reacts to these particles, creating beautiful aurorae, or Northern Lights. If the storm is really energetic, radio communications may be disrupted, satellites damaged, and even power grids disrupted. One giant eruption blacked out Canada's Quebec providence in 1989.

Mercury and the Moon have no weather, because they have no atmosphere. Pluto's weather is unknown, since no spacecraft has visited the last planet of the Solar System. Most likely, Pluto's atmosphere is so cold that no significant weather would be found.

Venus is perpetually cloudy, an example of a greenhouse effect gone wild; in addition, its clouds rain sulfuric acid. Mars is a planet that is well known for having weather. Clouds and dust storms are visible in backyard telescopes, as are polar ice caps. Jupiter' s storms are easily seen in backyard instruments. One storm, the Great Red Spot, had been documented for three hundred years, and lesser storms are frequently seen on the planets cloud belts. Saturn also displays rare variations in its cloud cover, revealing possible weather - features also available to larger backyard telescopes. Spacecraft have found Uranus and Neptune with similar variations in their cloud systems, again indications of atmospheric variations.

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