Friday, July 6
Saturday, July 7
Sunday, July 8
Monday, July 9
Tuesday, July 10
Vega passes the zenith around midnight.
Wednesday, July 11
Thursday, July 12
Friday, July 13
Saturday, July 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'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 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.
This Week's Planet Roundup
The Sun is displaying a spot group big enough to see without optical aid, just a safe solar filter. I can make out its elongated shape through a #14 arc-welder's shade. Active Region AR 1520 is nearing the midline of the Sun as of Wednesday, meaning it's aimed to blast some serious space weather our way if a big flare happens to erupt within it.
Mercury is disappearing deep in the sunset.
Venus and Jupiter (magnitudes –4.7 and –2.1) shine dramatically in the east-northeast before and during dawn. They remain stacked 5° or 6° apart this week, with Jupiter on top. Watch Aldebaran, much fainter, moving this week from below Venus to its right. Also in Venus's starry background are the Hyades, and above Jupiter are the Pleiades. The asteroids Ceres and Vesta, magnitudes 9.1 and 8.4, are there too! See article Predawn Treats for Early Risers for the naked-eye aspect, and to find the asteroids, Ceres and Vesta: July 2012 – April 2013.
Mars (magnitude +0.8, in Virgo) glows orange in the west-southwest at dusk and lower later. It's to the lower right of the Saturn-and-Spica pair by about 20°. It's heading their way; Mars will pass right between Saturn and Spica in mid-August.
In a telescope Mars is gibbous and very tiny (6.3 arcseconds wide), continuing to fade and shrink.
Saturn (magnitude +0.7, in Virgo) shines in the southwest as the stars come out. Below it by nearly 5° is Spica. After dark they move lower to the west-southwest.
Uranus (magnitude 5.8, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) are high in the southeast and south before the first light of dawn. 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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