As twilight fades

The Moon passes over Orion as it waxes through first quarter. (These scenes are 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. In the Far East, move it halfway. The blue 10° scale is about the size of your fist held at arm's length.)

Sky & Telescope


Friday, March 7

  • Look below the Moon this evening for orange Aldebaran, an orange giant star 65 light-years from Earth. Far off to their left is Betelgeuse in the top of Orion. Less far to their right are the Pleiades.

    Saturday, March 8

  • As the stars begin to come out, the first-quarter Moon shines above Orion standing in the south.

    Sunday, March 9

  • Jupiter shines above the Moon this evening, as shown above. Although they look fairly close together, Jupiter is almost 1,800 times farther away — and 40 times larger in diameter.
  • Episode 1 of the reborn Cosmos series airs tonight (Fox network, 9 p.m. Eastern, 8 Central). Its re-creation 34 years after the original is the cover story of the April Sky & Telescope — written by J. Kelly Beatty, who wrote the cover story introducing Carl Sagan's original Cosmos for our September 1980 issue.

    Monday, March 10

  • The Moon forms a distorted rectangle with Jupiter, Castor, and Pollux this evening. In addition, the Moon and Jupiter form a bent line of three with Procyon to their lower left.
  • Cosmos re-airs on the National Geographic Channel starting tonight (10 p.m. Eastern).

    Tuesday, March 11

  • Late twilight is when Sirius now stands due south, and twilight is also a time when the atmospheric seeing sometimes steadies. So it may be a good time to try to detect the faint white-dwarf companion of Sirius, now 10.2″ east of dazzling Sirius A. For tips on attempting this challenging project with at least a 6- or 8-inch telescope, see last October's Sky & Telescope, page 30.

    Wednesday, March 12

  • It's still 8 days until spring, so Orion's Belt isn't yet quite horizontal in early evening. But it's getting there, as Orion tips down toward the southwest for its seasonal decline and eventual departure.

    Leo watches on as the Moon waxes to full. This is the view at dusk as the stars come out.

    Sky & Telescope

    Thursday, March 13

  • Look left of the Moon this evening for Regulus. It's the bottom star in the handle of the Sickle of Leo.

    Friday, March 14

  • This evening, look for Regulus and the Sickle of Leo above the almost-full Moon.

    Saturday, March 15

  • The Big Dipper glitters high in the northeast these evenings, standing on its handle. You probably know that the two stars forming the front of the Dipper's bowl (currently on top) are the Pointers; they point to Polaris, currently to their left.

    And, you may know that if you follow the curve of the Dipper's handle out and around by a little more than a Dipper length, you'll arc to Arcturus, now rising in the east.

    But did you know that if you follow the Pointers backward, you'll land in Leo?

    Draw a line diagonally across the Dipper's bowl from where the handle is attached, continue far on, and you'll go to Gemini.

    And look at the two stars forming the open top of the Dipper's bowl. Follow this line past the bowl's lip far across the sky, and you crash into Capella.

    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).

    Pocket Sky Atlas

    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.

    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 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.

    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.

    Can a computerized telescope replace charts? Not for beginners, I don't think, and not on mounts and tripods that are less than top-quality mechanically (able to point with better than 0.2° repeatability, which means fairly heavy and expensive). 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

    Jupiter and Ganymede on March 2, 2014

    Unlike Jupiter's moons Io and Europa, Ganymede and Callisto are darker than most of Jupiter's surface, as seen dramatically in this high-resolution image of Ganymede near Jupiter's central meridian taken by Christopher Go at 11:20 UT March 2nd. You might even mistake it for its shadow! (The faint light ring that appears inside Ganymede is a processing artifact caused by its sharp dark edge against the lighter background).

    South is up. The reddish oval near Ganymede is Oval BA in the South Temperate Zone.

    Christopher Go

    Mercury (magnitude +0.2) is low above the east-southeast horizon during dawn, about 20° lower left of bright Venus.

    Venus (magnitude –4.7) shines as the bright "Morning Star" before and during dawn; look southeast.

    Mars (magnitude –0.7, in Virgo) rises around 9 p.m., a fiery blaze with icy Spica 5° or 6° to its right. The two are highest in the south around 2 a.m., with Spica now lower right of Mars.

    In a telescope Mars has grown to about 12½ arcseconds wide, on its way to an apparent diameter of 15.1″ when it passes closest by Earth in mid-April. See the telescopic Mars map and observing guide in the March Sky & Telescope, page 50.

    Jupiter, magnitude –2.4 in Gemini, dominates sky overhead during evening (for midnorthern skywatchers). See our articles on observing Jupiter in the January Sky & Telescope or the briefer online introduction Jupiter: Big, Bright, and Beautiful.

    Saturn (magnitude +0.4, in Libra) rises around 11 p.m. and is highest in the south before dawn. By then it's far left of Mars and Spica, and less far to the upper right of Mars-colored Antares.

    Uranus and Neptune are lost behind the glare of the Sun.

    "We may be little guys, but we don’t think small. It’s the courage of questions, of grasping our true circumstances, and not pretending we are at the center of it all, that is adulthood."
    — Ann Druyan, 2014

    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. Eastern Daylight (EDT) is UT minus 4 hours.

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