Friday, March 16
Saturday, March 17
Sunday, March 18
Monday, March 19
Tuesday, March 20
Wednesday, March 21
Thursday, March 22
Friday, March 23
Saturday, March 24
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 and tripods are less than top-quality mechanically (able to point with better than 0.3° repeatability). 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 has faded right out as it drops back into the glow of sunset. Its next good evening apparition won't come until the second half of June.
Venus and Jupiter are moving apart now but still form a spectacular pair in the western evening sky. They're 4° apart on March 16th and 9&@176; apart by the 23rd. Venus stays shining at about the same height at dusk all this month and next, but Jupiter is sliding lower. These are the two brightest celestial objects after the Sun and Moon, being magnitudes –4.4 and –2.1 now, respectively.
In a telescope Venus is a brilliant white "half moon" 22 arcseconds tall. Jupiter shows a much lower surface brightness, since it's farther from the Sun, but its apparent diameter is somewhat larger: 33 arcseconds.
Mars (magnitude –1.0) shines bright fire-orange in Leo. Fainter Regulus glitters 7° to its right or upper right during evening. Mars was at opposition on March 3rd; now it's starting to fade and shrink a bit as Earth pulls ahead of it along our faster, inside-track orbit around the Sun.
But at least Mars is shining higher in the evening sky now, reaching a good altitude for telescopic observing at a more convenient hour. It's at its highest in the south around midnight daylight saving time. Mars is still about 13.6 arcseconds wide, practically the same as its 13.9″ at opposition. It won't appear this big and close again until 2014. Watch the North Polar Cap continuing to dwindle; spring is about to give way to summer in Mars's northern hemisphere. See our Mars map and observing guide in the April Sky & Telescope, page 50.
Saturn (magnitude +0.3, in Virgo) rises in the east around 9 or 10 p.m. and shines highest in the south around 3 a.m. Accompanying it 6° to its right or upper right is Spica, about half as bright at magnitude +1.0 and bluer. In a telescope Saturn's rings are tilted 14.5° from our line of sight.
Uranus and Neptune are 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 Daylight Time (EDT) equals Universal Time (also known as UT, UTC, or GMT) minus 4 hours.
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