Some daily events in the changing sky for August 28 September 5.
Friday, August 28
Saturday, August 29
Sunday, August 30
Monday, August 31
Tuesday, Sept. 1
Wednesday, Sept. 2
Shortly afterward there's a double shadow transit on Jupiter, from 11:42 p.m. 12:47 a.m. PDT. And there's more going on too; details.
For a timetable of all of Jupiter's satellite phenomena throughout September, good worldwide, see the September Sky & Telescope, page 56.
Thursday, Sept. 3
Friday, Sept. 4
Saturday, Sept. 5
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 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 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 more detailed and descriptive Night Sky Observer's Guide by Kepple and Sanner, or the classic Burnham's Celestial Handbook). Read how to use them effectively.
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 and a curious mind." Without these, "the sky never becomes a friendly place."
More beginners' tips: "How to Start Right in Astronomy".
This Week's Planet Roundup
Mercury and Saturn are disappearing deep into the sunset. If you're ambitious, try sweeping for them with binoculars (preferably tripod-mounted) just above the horizon due west about 20 minutes after sunset. Saturn is getting farther to Mercury's right day by day. Don't be misled by Spica, sparkling off to their upper left.
Venus (magnitude 4.0, in Cancer) blazes in the east before and during dawn. Look for Procyon off to its right, and Sirius much farther to Procyon's right (and probably somewhat lower, depending on where you live).
Mars (magnitude +1.0, in the feet of Gemini) is high to the upper right of Venus before dawn. In a telescope it's still only 6 arcseconds wide: a tiny, fuzzy blob. Mars is on its way to a mediocre opposition late next January, when it will appear no larger than 14 arcseconds wide.
Jupiter (magnitude 2.8, in Capricornus) comes into view in the southeast as twilight fades the first "star" to appear after sunset. It's higher in better telescopic view by 10 p.m.
Jupiter impact mark fades. A black dust marking, like those made by the Comet Shoemaker-Levy 9 impacts in 1994, appeared suddenly in Jupiter's south polar region on July 19th. Backyard observers tracked it as it spread and elongated. Now it has broken up and faded nearly to invisibility. See our article.
Uranus (magnitude 5.8, just below the Circlet of Pisces) is well up in the southeast by 10 p.m.
Neptune (magnitude 7.8, in Capricornus) appears 5° from Jupiter but 20,000 times fainter. See our finder charts for Uranus and Neptune.
Pluto (14th magnitude, in northwestern Sagittarius) is still well up in the south-southwest right after dark. See the finder chart in the June Sky & Telescope, page 53.
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 (also known as UT, UTC, or GMT) minus 4 hours.
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