Minnesota Starwatch for February 2006
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Starwatch Newsletter

Minnesota Starwatch is a newsletter describing the night sky in the Midwest.

It is updated monthly, and is produced by the
Department of Astronomy, University of Minnesota
116 Church Street SE, Minneapolis, MN 55455

Minnesota Starwatch for February 2006

This is Minnesota Starwatch for February 2006. Full Moon is on the 12th this month and New Moon comes near the end of the month, the 27th.

Two Planets are especially worth mentioning right now. First, you can see Mars in the evening sky near the Pleiades (ply-ad-eez) star cluster, in the constellation Taurus. With good eyes you can see seven stars in the Pleiades; otherwise you may see only about five stars, or, if your eyes aren't so good, the whole bunch will look like a faint fuzz ball. In reality there are hundreds of stars there, close together in space about 400 light-years away. The Pleiades stars we see with the naked eye are far more powerful than the Sun, and the whole bunch are about 50 million years old, which is only 1/100th the age of the Sun.

One reason for mentioning this is that early February gives us a chance to exercise our imagination for distances. During the first week of the month the moon moves across our view of Mars and the Pleiades. Looking at that part of the evening sky on February 4th, 5th, or 6th, visualize what you're seeing: first, Mars is about twice as large as the Moon but more than 400 times as far away. What about the Pleiades, which seem close to Mars in the sky? Well, they're about 24 million times farther than Mars. The moonlight you see took only about a second to reach you from the Moon, and light from Mars is about nine minutes old when you see it this month. The light from the Pleiades started its journey to us about the time of Shakespeare and Galileo.

The other planet of note this month is Venus, because it's reappearing after an absence of a few weeks. Venus appears low in the southeast before sunrise this month, very bright but close to the horizon-at first sight you may think it's an approaching airplane. When we see Venus this way, it has just passed between Earth and the Sun and is now pulling away ahead of us.

Saturn and Jupiter are also visible now; Saturn is high in the sky at nightfall, but Jupiter doesn't rise until after midnight.

The Milky Way crosses the southern sky around 8 p.m. in February, in the constellations Gemini, Orion, and Canis Major. (You can spot Canis Major because Sirius, the brightest star, is there.) The winter Milky Way isn't very impressive, and there's a good reason. As most people know, the Milky Way is our disk-shaped galaxy; and the constellation Orion marks the direction straight outward, away from the galaxy's center. There are hundreds of billions of stars in the outer galaxy, but that's not enough to compare with those on the other side of the sky. On the other hand, most of the mysterious "dark matter" is in the outer parts of the Milky Way, far beyond the stars of Orion and Gemini. We know this because orbit speeds in the outer galaxy are too high to explain any other way.

For fun Astronomy Outreach programs check out our Public Outreach link, or if you're interested in how you can help build the new Minnesota Planetarium, please call 612-630-6151 or visit http://www.mplanetarium.org.

Como Planetarium is offering fun family shows about astronomy on a limited basis; please call 651-293-5398 for more info!

The Minnesota Starwatch is produced by the University of Minnesota Astronomy Department.