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The Night Sky of March

Dr. Wayne Wooten
Professor of Astronomy

For March, the moon is full on March 1st; this is the grass moon traditionally. The waning gibbous moon passes four degrees north of Jupiter on March 7th, with both rising about 11 p.m.. The last quarter moon passes four degrees north of Mars on March 9th, both rising just after midnight. The waning crescent moon passes two degrees north of Saturn in the dawn sky on March 10th. Remember to spring forward before you go to bed; daylight savings time begins on March 1th. New moon is on Saint Patrickís Day, March 17th. The young crescent moon lies south of bright Venus and fainter Mercury in evening twilight on March 18th; look for them in SW about 40 minutes after sunset. The Vernal Equinox occurs at 11:15 p.m.. CDT on March 20th to begin spring officially. The first quarter moon is on March 24th, and the blue moon, the second full moon for this month, is the Paschal Moon on March 31st.

Mercury and Venus play tag low in the SW after sunset as March begins. Use binoculars to catch the close conjunction as Mercury overtakes Venus on March 3-4, with Mercury about a degree north of bright Venus; look about 30 minutes after sunset. Mercury reaches greatest eastern elongation about 18 degrees from sun on March 15th. After that Mercury retrogrades back toward the sun, passing Venus again on March 18th, as the crescent moon joins them. While Venus climbs higher in western twilight as March ends, Mercury becomes lost in the Sunís glare as its passes between us and the Sun in last week of March.

Mars is in the morning sky in Sagittarius, and being overtaken by the faster moving earth. It brightens notably as we get closer, from +.8 to +.3 magnitude this month. When we do overtake it in August, it will be the closest and brightest it has appeared since August 2003. It is also closing in on fainter Saturn, with Mars only three degrees west of the ringed planet at monthís end. Jupiter is in Libra, and rises earlier each evening, about three hours after sunset by the monthís end. A good pair of binoculars will show the four large moons of Jupiter, in a row around Jupiterís equator. All three superior planets will be coming to opposition this summer, for some great telescopic viewing at our gazes at the Pensacola Beach Pavilion, Fort Pickens, and Big Lagoon State Park.

The constellation Cassiopeia makes a striking W in the NW. South of Cassiopeia is Andromedaís 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 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 in the northwest. 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; it is directly above us as darkness falls in early March. 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 southern 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 and among the youngest known stars.

In the east are 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 as darkness falls. 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, look for the bowl of the Big Dipper rising, with the top two stars, the pointers, giving you a line to find Polaris, the Pole Star. Here it sits unmoving 30 degrees high in on our northern sky locally. If you take the pointers of the Big Dipperís bowl to the 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". The folk wisdom that "March comes in like a Lion" probably refers to the head of Leo rising just after sunset in early March. Below the hind quarters of the lion is the "Leo Trio" of galaxiesNote the satellite trailing across his exposure. Galaxy M-65 at top left, M-66 at lower left, and almost edge on NGC 6538 at the right.

If you follow the handle of the Big Dipper to the south, by 9 PM you will be able to "arc to Arcturus", the brightest star of Spring and distinctly orange in color. It color is an indication of its uniqueness. It large speed and direction through the Milky Way suggests it was not formed with our Galaxy, but is a recent capture from the Sagittarius Dwarf Galaxy, a smaller satellite galaxy now being assimilated by our huge spiral galaxy. Many of its lost stars, like Arcturus, follow a band across the sky at about a 70 degree angle to our galactic plane. Arcturus is at the tail of kite shaped Bootes, the celestial bear driver chasing the two bears from his flocks. Spike south then to Spica in Virgo.

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