Friday, September 6
Saturday, September 7
Sunday, September 8
Monday, September 9
Tuesday, September 10
Wednesday, September 11
Thursday, September 12
Friday, September 13
Saturday, September 14
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.
This is an outdoor nature hobby. 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 guide to 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 with a telescope.
You'll also want a good deep-sky guidebook, such as Sue French's 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 beloved if dated Burnham's Celestial Handbook.
Can a computerized telescope replace charts? Not for beginners, I don't think, and not on mounts and tripods that are less than top-quality mechanically (able to point with better than 0.2° repeatability, which means heavy and expensive). As Terence Dickinson and Alan Dyer say in their invaluable 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 is hidden deep in the glare of sunset.
Venus and Saturn (magnitudes –4.1 and +0.7, respectively) hang low in the west-southwest in evening twilight, far lower left of Arcturus. Venus is the brightest but lowest. Saturn glimmers to Venus's upper left, a little closer every day. The star Spica begins the week just under Venus, then moves away to its lower right. Bring binoculars to help with Saturn and Spica.
The waxing crescent Moon pairs with Venus on the 8th — lovely! — and Saturn on the 9th, as shown at the top of this page.
Mars and Jupiter shine in the east before and during dawn. Jupiter, in Gemini, is the highest and brightest (magnitude –2.1). Look for fainter Mars (magnitude +1.6, in Cancer) increasingly far to Jupiter's lower left. Off to Mars's right or upper right shines Procyon, somewhat brighter.
Uranus (magnitude 5.7, in Pisces) and Neptune (magnitude 7.8, in Aquarius) are well up toward the southeast by 10 p.m. Finder charts for Uranus and Neptune.
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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