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The Night Sky of January

Dr. Wayne Wooten
Professor of Astronomy

For January 2020, the Quadrantid meteor shower will peak on the morning of Saturday, January 4th about 2 AM CST. Expect perhaps 20-30 meteors per hour coming out of the NE. Unlike most meteor showers made of decaying comets, this one’s origin is the "clay comet" asteroid Phaeton, which as its name implies, gets so close to the Sun its surface melts and sputters into space. WE have recently learned the asteroid Bennu, now orbited by NASA’s Orisis-REX, also has such surface activity! The first quarter moon, setting about midnight, will not interfere, so bundle up!

After the "Wolf" Full moon on January 10th, the waning moon is third quarter on January 17th. The crescent in the dawn is above Mars on the morning of January 20th, just west of Jupiter on January 22ndst. It is new on January 24th, and beneath Venus in the evening twilight on January 27th.

Venus is the only evening planet, dominating the SW twilight for the next several months. Mars is the dawn sky in Scorpius, and Jupiter in Sagittarius returns to the SE horizon by month’s end. Saturn still lies behind the Sun in January.

The constellation Cassiopeia makes a striking W in the NW. 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. Almost overhead as darkness falls, this fine shot of the Milky Way’s twin in space. Note the two companion galaxies, M-32 (on top) and M-110 (below)

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.

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 crew0.

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. It is part of a huge spiral arm gas cloud, with active starbirth all over the place. You should be able to glimpse this stellar birthplace as a faint blur with just your naked eyes, and the larger your binoculars or telescope, the better the view becomes.

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 p.m., 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". At 8 light years distance, Sirius is the closest star we can easily see with the naked eye. Below Sirius in binoculars is another fine open cluster, M-41, a fitting dessert for New Year’s sky feast.

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