Saturday, January 21

Sunday, January 22

Monday, January 23

Tuesday, January 24

Wednesday, January 25

Thursday, January 26

Friday, January 27

Saturday, January 28

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).

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 effectively.

You'll also want a good deep-sky guidebook, such as Sue French's new 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? 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."

Mars had grown to 9.0 arcseconds in diameter by January 1st, when Jim Phillips took this image with a 10-inch apo refractor and a Skynyx color video camera. The central-meridian longitude was 246°. South is up. The big dark prong at upper right is Syrtis Major. Note the white cloud haze on the right (morning) limb, and the patch of cloud near the evening terminator in Elysium next to dark Hyblaeus, lower left of center.

Jim Phillips

Venus (magnitude –4.0, in Aquarius) is the brilliant “Evening Star” shining in the southwest during and after dusk. It will continue to move a little higher each week all winter. In a telescope Venus is still a small gibbous disk, 14.5 arcseconds in diameter.

Mars (about magnitude –0.5, at the Leo-Virgo border) rises in the east around 9 p.m., far beneath Regulus and the Sickle of Leo. Mars is brightening rapidly now as it approaches Earth. It shines highest in the south, in best telescopic view, around 3 or 4 a.m. Mars has grown to 11½ arcseconds wide, on its way to 13.9″ when closest to Earth in early March.

Jupiter (magnitude –2.5, still at the Aries-Pisces border) shines highest in the south in early twilight, moves lower toward the southwest as evening advances, and sets in the west around midnight or 1 a.m. In a telescope Jupiter has shrunk to 40 arcseconds wide.

Jupiter is appearing smaller as Earth swings farther ahead of it in our faster orbit around the Sun. Christopher Go took this shot on January 18th at 11:20 UT, when large, dark Ganymede had recently left the planet's face and smaller, brighter Io was just about to. South is up, and the central-meridian longitude is 10°.

Writes Go, "The South Equatorial Belt is still very dark and active, while the North Equatorial Belt is very narrow now!" Note the thin, very long dark barge in the North North Temperate Belt.

Christopher Go

Uranus (magnitude 5.9, near the Circlet of Pisces) is in the southwest right after dark.

Neptune (magnitude 7.9, at the Aquarius-Capricornus border) is disappearing into the glow of evening twilight.

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 Standard Time (EST) equals Universal Time (also known as UT, UTC, or GMT) minus 5 hours.

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