Some daily events in the changing sky for July 18 – 26.
If you're in Europe or Asia, get ready for the eclipse of the Sun coming up on August 1st! It's at least partial over most of both continents. Skywatchers in easternmost Canada also have a partial view right at sunrise. See our article.
Friday, July 18
Saturday, July 19
Sunday, July 20
Monday, July 21
Tuesday, July 22
For lots more about observing Jupiter's moons, and a listing of all events happening among them this month, see the July Sky & Telescope, page 62.
Wednesday, July 23
Thursday, July 24
Friday, July 25
Saturday, July 26
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 foldout map in 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 maps; the standards are Sky Atlas 2000.0 or the smaller Pocket Sky Atlas) and good deep-sky guidebooks (such as Sky Atlas 2000.0 Companion by Strong and Sinnott, the even more detailed Night Sky Observer's Guide by Kepple and Sanner, or the classic Burnham's Celestial Handbook). Read how to use them effectively.
More beginners' tips: "How to Start Right in Astronomy".
This Week's Planet Roundup
Mercury (about magnitude –1.5) sinking deep into the glow of dawn. Early in the week, use binoculars to look for it above the east-northeast horizon 20 or 30 minutes before sunrise.
(To find your local sunrise time, and much else, make sure you've put your location and time zone into our online almanac. If you're on daylight saving time like most of North America, make sure the Daylight Saving Time box is checked.)
Venus (magnitude –3.9) is still very deep in the glow of sunset. Using binoculars, look for it just above the west-northwest horizon 20 to 40 minutes after sundown, as shown at the top of this page. Venus is making its way up very slowly toward a grand "Evening Star" showing in late fall and winter.
Mars and Saturn (magnitudes +1.7 and +0.8) are sinking lower in evening twilight, as shown at the top of this page. They're moving apart now; on July 18th they're separated by 4°, but on the 26th by 8°. Twinkly little Regulus (magnitude +1.4) remains 7° to Saturn's lower right. Look early before they all sink too low and set!
Jupiter (magnitude –2.7, in Sagittarius) shines with a steady glare in the southeast at nightfall. It's left of the Sagittarius Teapot and just below the bowl of the smaller, dimmer Teaspoon. Jupiter now gets its highest in the south by midnight daylight saving time. For high-resolution scopes, Jupiter's Great Red Spot and its little red companions have been putting on quite an interesting performance; see press release from the Hubble Space Telescope site.
Uranus and Neptune (magnitudes 6 and 8, respectively, in Aquarius and Capricornus) are high in the south before the first light of dawn. Use our article and finder charts.
Pluto (magnitude 14.0, in the northwestern corner of Sagittarius) is highest in the south in late evening. If you've got a big scope and a dark sky, use our article and finder chart. (Moonlight will be gone by the end of this week.)
All descriptions that relate to your horizon or zenith — 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 (UT, UTC, or GMT) minus 4 hours.
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