Saturday, Sept. 29

Sunday, Sept. 30

Monday, Oct. 1

Tuesday, Oct. 2

Wednesday, Oct. 3

Thursday, Oct. 4

Friday, Oct. 5

Saturday, Oct. 6

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).

Sky Atlas 2000.0 (the color Deluxe Edition is shown here) plots 81,312 stars to magnitude 8.5. That includes most of the stars that you can see in a good finderscope, and typically one or two stars that will fall within a 50× telescope's field of view wherever you point. About 2,700 deep-sky objects to hunt are plotted among the stars.

Sky & Telescope

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."

Jupiter's Great Red Spot had recently crossed the planet's central meridian when S&T's Sean Walker took this image on the morning of September 13th. South is up. Note that ring-like Red Spot Junior (Oval BA) is now passing just south of the Great Red Spot with no apparent effect on either of them. Walker used a 12.5-inch Newtonian telescope with a DMK 21AU618 astro video camera.

See our article Big Breakout on Jupiter on the dramatic growth this year of the North Equatorial Belt (below center here).

S&T: Sean Walker

Venus (magnitude –4.1, in Leo) rises in darkness around 4 a.m. daylight saving time (depending on where you live), emerging above the east-northeast horizon two hours before the first glimmer of dawn. By dawn it's blazing high in the east.

This week Venus is passing Regulus, which is only 1/150 as bright. They're closest on Wednesday morning October 3rd: separated by 0.2° or less before dawn in the Americas. Bring binoculars to help separate them!

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 or upper left. The gap between them shrinks from 16° to 11° this week. They're nearly the same brightness.

Jupiter (magnitude –2.5, in Taurus) rises in the east-northeast around 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 trace farther to Jupiter's left. By the beginning of dawn, this lineup-of-three stands high and diagonal in the south.

Saturn (magnitude +0.7) is becoming lost deep in the sunset, far to the lower right of Mars.

Uranus (magnitude 5.7, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) are up in the southeast 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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