Saturday, February 4

Sunday, February 5

Monday, February 6

Meanwhile, Jupiter's Great Red Spot transits the planet's central meridian around 9:32 p.m. EST. For timetables of all of Jupiter's satellite doings and Red Spot transits in February, see the February Sky & Telescope, page 53.

Watch the Moon advance eastward past Regulus and Mars. (This scene is drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. The blue 10° scale is about the size of your fist held at arm's length. For clarity, the Moon is shown three times actual size.)

Sky & Telescope diagram

Wednesday, February 8

Thursday, February 9

Friday, February 10

Saturday, February 11

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."

Venus is almost always totally featureless to visual observers, but digital stacked-video imaging can sometimes bring out the planet's subtle cloud patterns. These are especially visible in the near ultraviolet (UV). S&T's Sean Walker took these images through color filters on the evening of February 3rd, using the same equipment described for Mars below.

S&T: Sean Walker

Mars had grown to 12.2 arcseconds wide by February 5th, when S&T's Sean Walker took this image with a 12.5-inch Newtonian reflector and a DMK 21AU618.AS video camera. South is up. The North Polar Cap is the most obvious feature, but it's already shrinking in the of the Martian northern-hemisphere spring. The subtle bright area just right of center is Elysium, next to dark Hyblaeus. Note the cloud at Olympus Mons on the sunset terminator (at left; celestial west), and the faint cloud haze along the morning limb (right; celestial east).

S&T: Sean Walker

Venus (magnitude –4.1, in Pisces) is the most brilliant “Evening Star” shining in the southwest during and after dusk. It doesn't set now until a good two hours after dark. Venus will continue to appear a little higher, and stay up a little later, each week all this winter. In a telescope it's still a small gibbous disk, 15 or 16 arcseconds in diameter and 72% sunlit, as seen above. It will reach half-lit phase (dichotomy) in mid- to late March.

Mars (about magnitude –0.7, at the Leo-Virgo border) rises in the east around 8 p.m., far beneath Regulus and the Sickle of Leo. It's to the right or lower right of 2nd-magnitude Denebola. Mars is brightening rapidly as it approaches Earth. It shines highest in the south, in best telescopic view, around 2 or 3 a.m.

Jupiter is shrinking as Earth leaves it farther behind, but Christopher Go in the Philippines caught some excellent seeing on January 29th for this extraordinary shot of developments around the Great Red Spot. South is up. Note the white turbulence on the following (right; celestial east) side, and the stark red part of the South Equatorial Belt on the spot's preceding side.The red transitions to white as it squeezes past the spot.

Christopher Go

Jupiter (magnitude –2.3, still at the Aries-Pisces border) shines high in the south-southwest at dusk, moves lower toward the southwest as evening advances, and sets in the west around 11 or midnight. In a telescope Jupiter has shrunk to 39 or 38 arcseconds wide, as Earth pulls ahead of it in our faster orbit around the Sun.

Saturn (magnitude +0.6, in Virgo) rises in the east around 11 and is shines highest in the south before dawn. Spica, a bit fainter at magnitude +1.0, is 7° to its right or upper right. Saturn's rings are now tilted a generous 15° from our line of sight. This is the most open the rings have appeared since 2007.

Saturn's rings are tipped a good 15° from our line of sight. South is up. Note the very pale light band in the north temperate region, apparently the remnant of the dramatic, billowing white outbreak that attracted so much attention last year. Christopher Go took this image on January 21, 2012.

Christopher Go

Neptune is lost in 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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