Friday, October 5
Before all this, Jupiter's Great Red Spot should cross the planet's central meridian around 11:47 p.m. EDT.
For all of Jupiter's satellite events and Great Red Spot transits this month, good worldwide, see "Action at Jupiter" in the October Sky & Telescope, page 53.
Saturday, Oct. 6
Glance up at Algol at any random time, and you have a 1 in 30 chance of catching it at least 1 magnitude fainter than normal.
Sunday, October 7
Monday, October 8
Tuesday, October 9
Wednesday, October 10
Thursday, October 11
Friday, October 12
Saturday, October 13
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 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 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.
Can a computerized telescope replace charts? Not for beginners, I don't think, and certainly not on mounts and tripods that are less than top-quality mechanically (able to point with better than 0.2° repeatability). 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 buried deep in the sunset.
Venus (magnitude 4.1, in Leo) rises in darkness around 4 a.m. daylight saving time (depending on where you live), coming above the eastern horizon almost two hours before the first glimmer of dawn. By dawn it's shining brightly high in the east.
Look above or upper right of Venus for Regulus, much fainter. Regulus pulls farther away from it every day.
Mars (magnitude +1.2, in Libra) remains low in the southwest in evening twilight. Don't confuse it with twinklier orange Antares ("Anti-Mars") to its left. The gap between them shrinks from 11° to 7° this week. They're nearly the same brightness.
Jupiter (magnitude 2.6, in Taurus) rises in the east-northeast around 9 or 10 p.m. daylight saving time. Once it's clear of the horizon, look for fainter orange Aldebaran twinkling 8° to its right and Beta Tauri (Elnath) a similar distance to Jupiter's left. By dawn this lineup-of-three stands high and almost vertical in the southwest.
Saturn is lost in the sunset.
Uranus (magnitude 5.7, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) are in the southeast to south during evening. 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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