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The Night Sky of January

Dr. Wayne Wooten
Professor of Astronomy

For January 2010, the Moon will be a day past full on New Year's Day. The first two weeks find the moon waning in the morning sky. The waning gibbous moon passes six degrees south of Mars on January 3rd, with both rising about 9 PM in east. The last quarter moon sits high in the sky about six degrees south of Saturn overhead on the morning of January 6th. The new moon is on January 15th, and creates an annular solar eclipse visible in the Indian Ocean. The waxing crescent moon passes north of Jupiter in the southwestern evening sky on January 17th, with first quarter on the 23rd, and Full Moon on January 30th to end the month. For northern Indian tribes, this was the Wolf or Snow Moon….before global warning, obviously….

While the naked eye, dark adapted by several minutes away from any bright lights, is a wonderful instrument to stare up into deep space, far beyond our own Milky Way, binoculars are better for spotting specific deep sky objects. For a detailed map of northern hemisphere skies, about January 1st visit the website and download the map for January; it will have a more extensive calendar, and list of best objects for the naked eyes, binoculars, and scopes on the back of the map. Also available as the next month begins is wonderful video exploring the January sky, featuring many different objects, available from the Hubble Space Telescope website at:

Mercury and Venus lie too close to sun for good viewing this January. Mars will be coming to opposition on January 29th, rising in the east at sunset, and closest and largest in the scope until 2012. Its red disk will reveal surface detail and polar caps with moderate sized amateur scopes at 200X and higher. It will be the brightest think in the eastern evening sky for all of the winter of 2010. But Jupiter is about to vanish into the Sun's glare, low in the SW by the end of the month. This is an interesting month for Saturn. Children will be disappointed, for the famed rings are still very thin, but starting to open up week by week! They were edge on as seen from the Earth last fall, and will be tilted 27 degrees toward us at solstice in 2017, when they will double the planet's present brightness. Saturn is in the morning sky in the tail of Leo now, but comes to opposition and moves into evening sky by end of March.

The square of Pegasus dominates the western sky. The constellation Cassiopeia makes a striking W in the NW. She contains many nice star clusters for binocular users in her outer arm of our Milky Way, extending to the NE now. Her daughter, Andromeda, starts with the NE corner star of Pegasus'' Square, and goes NE with two more bright stars in a row. It is from the middle star, beta Andromeda, that we proceed about a quarter the way to the top star in the W of Cassiopeia, and look for a faint blur with the naked eye. M-31, the Andromeda Galaxy, is the most distant object visible with the naked eye, lying about 2.5 million light years distant. Overhead is Andromeda's hero, Perseus, rises. Between him and Cassiopeia is the fine Double Cluster, faintly visible with the naked eye and two fine binocular objects in the same field. Perseus contains the famed eclipsing binary star Algol, where the Arabs imagined the eye of the gorgon Medusa would lie. It fades to a third its normal brightness for six out of every 70 hours, as a larger but cooler orange giant covers about 80% of the smaller but hotter and thus brighter companion as seen from Earth.

Look at Perseus' feet for the famed Pleiades cluster; they lie about 400 light years distant, and over 250 stars are members of this fine group. East of the seven sisters is the V of stars marking the face of Taurus the Bull, with bright orange Aldebaran as his eye. The V of stars is the Hyades cluster, older than the blue Pleaides, but about half their distance. Mars now lies in the horns of Taurus as January begins, and was at greatest brilliance at opposition around last Christmas.

Yellow Capella, a giant star the same temperature and color as our much smaller Sun, dominates the overhead sky. It is part of the pentagon on stars making up Auriga, the Charioteer (think Ben Hur). Several nice binocular Messier open clusters are found in the winter milky way here. East of Auriga, the twins, Castor and Pollux highlight the Gemini. UWF alumni can associate the pair with Jason and the Golden Fleece legend, for they were the first two Argonauts to sign up on his crew of adventurers.

South of Gemini, Orion is the most familiar winter constellation, dominating the eastern sky at dusk. The reddish supergiant Betelguese marks his eastern shoulder, while blue-white supergiant Rigel stands opposite on his west knee. Just south of the belt, hanging like a sword downward, is M-42, the Great Nebula of Orion, an outstanding binocular and telescopic stellar nursery. A lesser known but also photogenic stellar nursery is the Rosette, east of Betelguese. It contains the nice binocular cluster NGC 2244, but the flowery pattern of glowing pink hydrogen shows up best in long exposure photos with larger scopes. The cluster forms from the inside out, as hot new stars light up the cocoons of gas and dust and push them outward. Some of these dust lanes show up nicely in John's fine flower of the skies.

Last but certainly not least, in the east rise the hunter's two faithful companions, Canis major and minor. Procyon is the bright star in the little dog, and rises minutes before Sirius, the brightest star in the sky. Sirius dominates the SE sky by 7 PM, and as it rises, the turbulent winter air causes it to sparkle with shafts of spectral fire. Beautiful as the twinkling appears to the naked eye, for astronomers this means the image is blurry; only in space can we truly see "clearly now". You must be in south Florida to spot Alpha Centauri on June evenings. Below Sirius in binoculars is another fine open cluster, M-41, a fitting dessert for New Year's sky feast.

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