Friday, February 24
Saturday, February 25
Sunday, February 26
Monday, February 27
Tuesday, February 28
Wednesday, February 29
Thursday, March 1
Then later tonight, the Moon's dark limb covers 3rd-magnitude Zeta Tauri for the Northeast and much of the Midwest. Some times: Toronto, 1:25 a.m. EST; Washington, DC, 1:36 a.m. EST; Chicago, 12:39 a.m. CST; Winnipeg, 12:16 a.m. CST. More times.
Friday, March 2
Saturday, March 3
Want to become a better amateur astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
For an easy-to-use constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential magazine of astronomy. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).
Once you get a telescope, to put it to good use you'll need a detailed, large-scale sky atlas (set of charts). The standards are the little Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger and deeper Sky Atlas 2000.0 (stars to magnitude 8.5); and the even larger Uranometria 2000.0 (stars to magnitude 9.75). And read how to use sky charts effectively.
You'll also want a good deep-sky guidebook, such as Sue French's new Deep-Sky Wonders collection (which includes its own charts), Sky Atlas 2000.0 Companion by Strong and Sinnott, the bigger Night Sky Observer's Guide by Kepple and Sanner, or the classic if dated Burnham's Celestial Handbook.
Can a computerized telescope replace charts? I don't think so — not for beginners, anyway, and especially not on mounts that are less than top-quality mechanically. As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."
This Week's Planet Roundup
Mercury (about magnitude –1.0) is emerging into its best evening apparition of 2012. As the afterglow of sunset fades in the west, look for Mercury far to the lower right of bright Venus.
Venus and Jupiter (magnitudes –4.2 and –2.2) are the two bright “Evening Stars” shining in the southwest to west during and after dusk. Venus is the brighter, lower one. Watch Jupiter closing in on it by 1° every day! The gap between them narrows this week from 17° to 10°. These are the two brightest celestial objects after the Sun and Moon.
In a telescope, Venus is a brilliant white gibbous disk 18 arcseconds tall and 65% sunlit. Jupiter shows a much lower surface brightness, being farther from the Sun, but it's bigger: 36 arcseconds wide.
Mars (about magnitude –1.2, in western Leo) is nearing its March 3rd opposition. It rises bright fire-orange in the east during twilight and dominates the eastern sky after dark. The star to its left or lower left is Denebola, the tail of Leo. Mars shines highest in the south, in best telescopic view, around midnight or 1 a.m.
In a telescope Mars has grown to 13.7 or 13.8 arcseconds wide, basically identical to the 13.9″ it will display when it's nearest to Earth March 5th.
Saturn (magnitude +0.5, in Virgo) rises in the east around 10 p.m. and shines highest in the south around 3 or 4 a.m. Spica, a little fainter at magnitude +1.0 (and bluer), is 7° to Saturn's right or upper right. Saturn's rings are tilted a generous 15° from our line of sight, the most open the rings have appeared since 2007.
Uranus is disappearing into the sunset.
Neptune is hidden behind the glare of the Sun.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America. Eastern Standard Time (EST) equals Universal Time (also known as UT, UTC, or GMT) minus 5 hours.
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