Sky at a Glance, May 16 – 24

Friday, May 16

Look for Mercury as twilight darkens. It's low in the west-northwest, far to the lower right of Jupiter and lower left of Capella. Mercury is having its highest showing of 2014 (for skywatchers at mid-northern latitudes).

Saturday, May 17

Arcturus shines high in the southeast these nights. Vega shines much lower in the northeast. Look a third of the way from Arcturus to Vega for dim little Corona Borealis, the Northern Crown, with its one modestly bright star, Alphecca or Gemma. Two thirds of the way from Arcturus to Vega glimmers the dim Keystone of Hercules. Continue on down past Vega, and you hit Cygnus.

Sunday, May 18

Look south after dark for Mars at its highest. Straight below Mars, by more than a fist at arm's length, is the distinctive springtime constellation Corvus the Crow. Its four brightest stars form a distorted rectangle less than a fist in size.

Venus and the waning crescent Moon

As dawn brightens next weekend, watch the waning crescent Moon approach Venus.

Monday, May 19

Now that Vega is well up in the northeast in the evening, look to its lower left (by two or three fists) for Deneb. As Deneb rises higher through the night, a dark sky will reveal that it lies inside the Milky Way band looming up all across the eastern sky.

Tuesday, May 20

As the stars come out, Saturn in the southeast, Vega in the northeast, Capella in the northwest, and Procyon in the west-southwest are all at about the same altitude (as seen from about 40° north latitude).

Wednesday, May 21

The western twilight Arch of Spring is sinking, but you can still catch this big landmark when the stars come out. Jupiter in the west lies within it. Pollux and Castor, above Jupiter, are lined up roughly horizontally; they're the Arch's top. Look far to their lower left for Procyon, and farther to their lower right for Menkalinen and then bright Capella. Jupiter is moving closer to the Arch's upper-left side.

Thursday, May 22

As twilight fades, spot Mercury low in the west-northwest. It's about 2½ fists to the lower right of bright Jupiter. This evening Mercury is between the horn-tips of Taurus: Beta Tauri (El Nath) to its upper right, and Zeta Tauri to its lower left. Binoculars will help.

Friday, May 23

New meteor shower? A possible strong meteor shower may arrive in the early-morning hours of Saturday the 24th, timed for North America (perhaps peaking around 3 a.m. EDT, midnight PDT). For just a few hours we'll pass through the predicted debris trail of Comet 209P/LINEAR, which is making an unusually close flyby of Earth. There's even a (slim) possibility that the shower could approach "meteor storm" proportions. The comet itself is closest on May 29th, but it's very small and faint and may reach 11th magnitude at best. For more about watching for the meteor shower, see the May Sky & Telescope, page 30.

As dawn brightens on Saturday morning the 24th, look for Venus well to the lower left of the waning crescent Moon, as shown above.

Saturday, May 24

Low in the dawn of Sunday the 25th for the Americas, Venus shines beautifully below the thin crescent Moon, as shown above. Look east.


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 it's still less than one per square degree on the sky. Also plotted are many hundreds of telescopic galaxies, star clusters, and nebulae.

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 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

Mars-by-Rick-Schrantz_5-7-2014

Mars on May 7th, imaged by Rick Schrantz from his patio in Nicholasville, Kentucky. He used a homemade 10-inch f/7.5 reflector at f/43 with a DMK21AU618.AS planetary video camera. South is up. The light patches near center are thin clouds over Elysium. The dark band at upper left is Mare Cimmerium.

Jupiter by Christopher Go, May 12, 2014

Jupiter on May 12th as imaged by Christopher Go in the Philippines. South is up. Notice how chopped up this stretch of the North Equatorial Belt is on its border with the Equatorial Zone. (The central-meridian longitude is 160°.) To get an idea of the visual telescopic appearance, brighten the image, reduce the contrast, stand back and squint your eyes. The raggedness of the NEB's southern edge is still quite visible.

Saturn-by-Damien-Peach_April-14-2014

You never see images of Saturn taken from Earth finer than this. Damien Peach in the U.K. used a 12-inch Schmidt-Cassegrain scope, and many years of experience, to obtain this view on April 14th. South is up. He writes, "Many fine details can be seen in this true RGB image. Note the small white spot in the mid-northern latitudes [very subtle!]. Otherwise things look very quiet. "

Mercury (about magnitude 0) is having its highest evening apparition of 2014 for skywatchers at mid-northern latitudes. As twilight fades, look for it in the west-northwest far to the lower right of bright Jupiter and lower left of Capella. Mercury loses some of its brightness this week.

Venus (magnitude –4.0) is the bright "Morning Star" low due east during dawn. How late into the brightening daylight can you follow it?

Mars (magnitude –0.8, in Virgo) shines highest in the south in late twilight. It sets in the west before the first light of dawn. Just left of Mars in the evening is 3rd-magnitude Porrima, and far lower left of it sparkles Spica.

In a telescope, Mars's gibbous disk shrinks from 13.2 to 12.4 arcseconds tall this week. See the Mars map and observing guide in the March Sky & Telescope, page 50. Use our Mars Profiler to find which side of the planet will be facing Earth when you plan to look.

Jupiter (magnitude –1.9, in Gemini) shines brightly in the west in twilight, under Pollux. It sinks during the evening and sets around midnight. In a telescope Jupiter has shrunk to 34″ across its equator.

Saturn (magnitude +0.1, in Libra) is just past its May 10th opposition. It shines in the southeast during evening and stands highest in the south around midnight. Look for Antares and the head of Scorpius well to its lower left. Watch Saturn creeping closer to fainter Alpha Librae week by week.

In a telescope Saturn's globe is 19″ wide, and its rings are tilted a nice 22° from our line of sight. Use our SaturnMoons app to find and identify Saturn's various satellites at any time and date.

Uranus and Neptune are still fairly low before or during dawn.

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"It is a great tragedy that science, this wonderful process for finding out what is true, has ceded the spiritual uplift of its central revelations: the vastness of the universe, the immensity of time, the relatedness of all life, and life’s preciousness on our tiny planet."
— Ann Druyan, 2014. The remade Cosmos series continues Sunday nights on Fox and Mondays on National Geographic. Watch recent episodes online anytime.


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) is Universal Time (UT, UTC, or GMT) minus 4 hours.