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The Night Sky of February

Dr. Wayne Wooten
Professor of Astronomy

For February, the Moon will be last quarter on February 1st, rising at midnight, and only 3 degrees north of reddish Mars. On February 3rd, the waning crescent moon will pass 4 degrees north of Saturn in the dawn sky. On the 6th, the moon lies 4.3 degrees north of Venus, and 3.9 degrees north of Mercury in the dawn sky. The moon is new on February 8th. The first quarter moon is on February 15th, and full moon on February 22nd; this is the "hunger" moon in Native American tradition, when most of the food stored up for winter was almost gone. The waning gibbous moon passes just 1.6 degrees south of Jupiter on February 24th, with both rising about two hours after sunset.

Mercury is low in the morning sky, reaching greatest western elongation on February 7th. It is easiest to find on February 13th, when it is only 4 degrees east of Venus. Venus dominates the dawn sky for the next few weeks, but will be lost behind the sun in April. Mars is being overtaken by the faster moving Earth, and will come to opposition on May 21st, when it will be closest to us and brightest in 2016. Look for it in Libra near the moon on February 1st. Jupiter is in southeastern Leo, and comes to opposition on March 8th. Jupiter dominates the late evening eastern sky, rising almost at sunset by the monthís end. The ringed planet will be coming to opposition on June 2nd, and is now north of Antares in Scorpius, rising about 3 Am at the start of the month. The rings are much more open than last year, and are open about 27 degrees now, when fully opened at Saturnís solstice this year; when this open, the huge reflecting surface of the ringís ice boulders will double the planetís brightness.

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 Pegasusíí 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 Andromedaís 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.

At Perseusí 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 Pleiades, 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 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. The bright diamond of four stars that light it up are the trapezium cluster, one of the finest sights in a telescope.

In the east rise the hunterís 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". At 8 light years distance, Sirius is the closest star we can easily see with the naked eye from West Florida.

When Sirius is highest, along our southern horizon look for the second brightest star, Canopus, getting just above the horizon and sparkling like an exquisite diamond as the turbulent winter air twists and turns this shaft of starlight, after a trip of about 200 years!

To the northeast, a reminder that spring is coming; look for the bowl of the Big Dipper to rise, with the top two stars, the pointers, giving you a line to find Polaris, the Pole Star. But if you take the pointers south, you are guided instead to the head of Leo the Lion rising in the east, looking much like the profile of the famed Sphinx. The bright star at the Lionís heart is Regulus, the "regal star". Fitting for our cosmic king of beasts, whose rising at the end of this month means March indeed will be coming in "like a lion". Note that Jupiter now sits just south of the tail of Leo, and will be moving from Leo into Virgo by mid year.

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