Friday, May 6
Saturday, May 7
Sunday, May 8
Monday, May 9
Tuesday, May 10
Wednesday, May 11
Thursday, May 12
Friday, May 13
Saturday, May 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.
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 must have a detailed, large-scale sky atlas (set of charts). The standards are the Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger Sky Atlas 2000.0 (stars to magnitude 8.5); and the even larger and deeper 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 Sky Atlas 2000.0 Companion by Strong and Sinnott, or the more detailed and descriptive Night Sky Observer's Guide by Kepple and Sanner, or the classic if dated Burnham's Celestial Handbook.
Can a computerized telescope take their place? 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, Venus, Mars, and Jupiter are deep in the bright glow of dawn. Use binoculars 20 or 30 minutes before sunrise; look low in the east. Venus is by far the brightest. Second-brightest is Jupiter, which passes 0.6° from Venus on the morning of May 11th (for the time zones of the Americas). Below Venus all week is brightening Mercury. Faint little Mars is a challenge object to their lower left.
Saturn (magnitude +0.6, in Virgo) is the only planet in good telescopic view. Look for it high in the southeast as the stars come out, with Spica twinkling to its lower left and bright Arcturus about twice as far to its upper left. Saturn shines highest in the south around 10 or 11 p.m. daylight saving time not long after dark now.
In a telescope, Saturn's rings have narrowed slightly in the last few months to 7.6° from edge on. The pointlike source of Saturn's months-old white streak has rebrightened, as imaged here. See how many of Saturn's satellites you can identify in your scope using our Saturn's Moons tracker.
The fainter star Gamma Virginis (Porrima) is only about 1° upper right of Saturn after dark. Gamma Vir is an attraction in its own right: a fine, close telescopic binary star with a current separation of 1.7 arcseconds. Use high power and hope for good seeing. See article in the April Sky & Telescope, page 56. Saturn will keep closing in on Gamma Vir until passing 0.4° from it in mid-June.
Uranus (magnitude 5.9, in western Pisces) is still in the dawn glow.
Neptune (magnitude 7.9, in Aquarius) is low in the southeast just before dawn's first light.
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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