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The Night Sky of February

Dr. Wayne Wooten
Professor of Astronomy

For February 2010, the Moon will be a waning gibbous as the month begins, having passed seven degrees south of Saturn in the morning sky on Ground Hog Day, February 2nd. The last quarter moon is high overhead on the morning of February 5th, and the moon is new a week later, on Valentine's Day, February 14th. The last two weeks find the moon waxing in the evening sky. The slender crescent moon lies four degrees north of Jupiter in the evening twilight on February 15th, but you may need binoculars to get a last glimpse of the giant planet as it disappears behind the Sun for the next several weeks, to return to the morning sky in late March. First quarter moon sits high in the sky and half-lit at sunset on February 22nd. The full moon is on February 28th and in folklore, is the Wolf or Hunger Moon.

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 February 1st visit the website and download the map for February 2010; 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.

Venus returns to the evening sky and passes less than a degree south of Jupiter low in the SW on February 17th; look about 20 minutes after sunset to spot the pair. Jupiter is vanishing behind the Sun, but Venus will climb higher in the evening sky for the next several months, to dominate the western evenings. Through the telescope, Venus now appears as a small, round disk, on the far side of the Sun. She will appear larger as she approaches Earth and overtakes us, but her phase will become less sunlit as well. It was Galileo in 1611 who noted that Venus goes through this entire phase cycle, and correctly deduced this proved she orbited the Sun, not us. Covered with sulfuric acid clouds, her bright disk reveals only her phase, with no visible cloud details in the scopes.

While Jupiter disappears in the south west, opposite him in the north eastern evening sky, Mars is big and bright and orange red to catch the attention of any novice star gazer. He reached opposition and rose at sunset on January 29th, with the Full Moon passing six degrees south of him on January 30th. While placed high overhead in Cancer about midnight now, Mars is not as close to us this opposition as he was back in August of 2003, due to Mar's rather elliptical orbit. Still, high power views with amateur telescopes will reveal polar caps, clouds, reddish rusty deserts, and dark lava flows on this world most similar to our own in surface conditions, as the Mars orbiters and rovers continually reveal.

Saturn is now in Virgo, past the tail of Leo the Lion, and rising about 10 PM as February begins, but coming to opposition on March 22nd, just after the Vernal Equinox. The rings are gradually starting to open up again, but still rather thin, only tilted about 10 degrees now, compared to 27 degree when fully opened at Saturn's solstice in 2016; when this open, the huge reflecting surface of the ring's ice boulders will double the planet's 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 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.

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 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 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'. At 8 light years distance, Sirius is the closest star we can easily see with the naked eye from West Florida.

About seven degrees north east of Sirius lies IC 2177, the Seagull Nebula. Not visible to the naked eye or even with binoculars, it is still photogenic as in the photo to the left showing it about to grab a cosmic bread crumb out of the heavens. The crumb is a Bok Globule, a condensing star probably forming planets around it…while the wispy wings of the Seagull are probably being blown apart by the pressure of intense light from nearby stars which makes them shine. All is not as it first seems, even in the heavens.

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 of Spring 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 Lion's 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.

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