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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 7th, with bright Jupiter 4 degrees south of it and both rising about midnight in the SE. The waning crescent moon is 4 degrees north of Mars on the morning of February 8th. The crescent moon passes 2 degrees north of Saturn on February 11th. The new moon is on February 15th, with the Chinese New Year celebrated with the appearance of the waxing crescent the following evening. The moon is first quarter on February 23rd.

This month is unusual in that being February, with only 28 days, it does not have a full moon at all! They occur on January 31st, then again on March 2nd! All other months must have full moons, as the synodic cycle of the moon’s recurring phases takes 29.5 days.

Mercury and Venus are too close to Sun for easy observing this month. Venus will pass behind the sun and return to the evening sky later this spring. Mars passed Jupiter in the dawn in January, and will not return to the evening sky until its close and bright opposition next July. Jupiter also lies in the morning sky, and like Saturn, will be best seen in summer and autumn evening skies.

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. Timely for Valentines is the faint but photogenic "Heart Nebula", IC 1805. This photo by EAAA member Ed Magowan shows it nicely.

Cassiopeia’s 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. 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 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 hunter’s two faithful companions, Canis major and minor. Procyon is the bright star in the little dog, and rises before Sirius, the brightest star in the sky. Midway between them is the fine Rosette Nebula, a star nursery of gas and dust including the nice open cluster NGC 2244, easily found in binoculars. Several other nice clusters for binoculars are also plotted on your February sky map printout, be sure to check them out some clear, crisp winter evening.

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 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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