Supernova in M82! An 11th-magnitude supernova has gone off in the galaxy M82 in Ursa Major. It's in the evening sky in reach of amateur telescopes, and it may not be done brightening yet. See our article Bright Supernova in M82, with ongoing updates.
Every day, Mercury is getting higher and easier to spot after sundown.
Friday, January 24 Mercury is becoming easy to spot; look for it low in the west-southwest as twilight fades, as shown above. Mercury is beginning its best evening apparition since last June for mid-northern skywatchers. See our article.
The Moon rises around 2 a.m. Saturday morning, with Saturn glowing just 1° or 2° from it (as seen from the Americas). They're high in the south together by dawn, as shown at right.
Waning further, the dawn Moon now passes Saturn and Antares. (The Moon is shown three times actual size.)
Saturday, January 25 Algol is at minimum brightness, magnitude 3.4 instead of its usual 2.3, for a couple hours centered on 10:09 p.m. EST. It takes several additional hours to fade and to rebrighten. Jupiter's Great Red Spot transits Jupiter's central meridian around 11:01 p.m. EST.
Sunday, January 26 This is the frigid time of year when the Little Dipper (mostly dim) hangs straight down from Polaris shortly after dark. Look due north.
Monday, January 27 In the dawn Tuesday morning the 28th, make a point to look low in the southeast to catch Venus with the waning crescent Moon to its right, as shown at lower right. A telescope shows that Venus too is a crescent!
Up for work at dawn? Watch the waning crescent Moon pass Venus. (The scene is drawn for the middle of North America; your view may differ a bit. The Moon is shown three times life size.)
Tuesday, January 28 Algol is at minimum brightness for a couple hours centered on 7:00 p.m. EST.
In Wednesday's dawn, look for the eerily thin waning crescent Moon below Venus now. They're low in the southeast, as shown here.
Wednesday, January 29 Jupiter this month turns the Winter Triangle into a bigger, brighter Winter Diamond. Its bottom is Sirius, its two side corners are Betelgeuse and Procyon, and Jupiter forms its top. The diamond tilts leftward in early evening and stands vertically in the south around 10 p.m. (depending on your location).
Thursday, January 30 You may be familiar with the Double Cluster in Perseus. But do you know the clusters Stock 2, King 4, Trumpler 2, and NGC 957 right near it? Pick them out with Sue French's Deep-Sky Wonders article and chart in the February Sky & Telescope, page 56.
Friday, January 31 The Moon is back in the evening sky, as a thin waxing crescent to the lower right of Mercury. Look very low above the west-southwest horizon in twilight, as shown here.
Back in the evening sky, the waxing Moon passes Mercury after sundown.
Saturday, February 1 Mercury shines below the thin crescent Moon low in the west-southwest after sunset, as shown here. Jupiter's moon Ganymede casts its tiny black shadow onto Jupiter from 5:42 to 8:22 p.m. EST. Jupiter's Great Red Spot crosses the planet's central meridian around 11:48 p.m. EST (8:48 p.m. PST).
Want to become a better astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
This is an outdoor nature hobby. 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 once you know your way around, the even larger Uranometria 2000.0 (stars to magnitude 9.75). And read how to use sky charts with a telescope.
The Pocket Sky Atlas
plots 30,796 stars to magnitude 7.6 which may sound like a lot, but that's less than one star in an entire telescopic field of view, on average. By comparison, Sky Atlas 2000.0
plots 81,312 stars to magnitude 8.5, typically one or two stars per telescopic field. Both atlases include many hundreds of deep-sky targets galaxies, star clusters, and nebulae to hunt among the stars.
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 beloved if dated Burnham's Celestial Handbook.
This Week's Planet Roundup
Mercury (magnitude –0.9) is having an excellent apparition in the evening twilight. Look low in the west-southwest as twilight fades.
Gibbous Mars was still just 7.1 arcseconds from pole to pole on January 6th when Don Parker in Florida imaged it with a 16-inch reflector. South is up. Note the North Polar Cap with hints of a rift already developing, morning clouds near the following (celestial east; right-hand) limb, haze visible over the dark Syrtis Major region on the opposite (preceding) limb, and in the south, distinctive Sinus Sabaeus ending with two-pronged Sinus Meridiani.
Donald C. Parker
Venus (magnitude –4.6) shines brightly in the dawn; look east-southeast. It gets higher every day. Venus is revealed as a crescent in a telescope or even good binoculars.
Mars (magnitude +0.4, in Virgo) rises around 11 p.m. It's just 5° from Spica, not quite as bright, to its lower right. Compare their colors; Spica is icy blue-white. They're highest in the south around 4 a.m., with Spica now under Mars.
In a telescope Mars is about 8 arcseconds wide. It'll appear nearly twice this diameter (15.1″) when passing closest to Earth in mid-April.
Jupiter (magnitude –2.6, in Gemini) dominates the eastern sky in early evening and crosses nearly overhead (for mid-northern observers) around 10 p.m.
Jupiter on the night of January 9–10, taken from New Hampshire by S&T's imaging editor Sean Walker. South is up. The Great Red Spot, unusually strong orange this season, is obvious even near the limb. Following (celestial east) of it is a long, diminishing series of white swirls in the South Equatorial Belt. Notice the tight trio of white ovals in the South South Temperate Belt, and the blue festoons in the Equatorial Zone.
S&T: Sean Walker
In a telescope Jupiter remains a big 46 arcseconds wide. For lots about observing Jupiter see the January Sky & Telescope or our brief article online: Jupiter: Big, Bright, and Beautiful.
Saturn (magnitude +0.5, in Libra) rises around 1 or 2 a.m. and is high in the south-southeast as dawn begins to brighten. By then it's far to the left of Mars and Spica (and less far to the upper right of Antares).
Uranus (magnitude 5.9, in Pisces) is still findable in the west-southwest right after dark. Finder chart.
Neptune is beginning to disappear into the 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) is Universal Time (UT, UTC, or GMT) minus 5 hours.
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