Rare Eclipse of the Lunar Kind

Et tu, luna! A total penumbral lunar eclipse awaits on the eve of the Ides of March.

In this rare kind of eclipse, the Earth stands exactly between the sun and the moon as the moon crosses through Earth's outer perimeter shadow, or penumbra. This is not a total lunar eclipse, which occurs when the moon runs through the shadow core and turns a rusty brown. In a penumbral eclipse, the color change is more subtle.

Using the late astronomer Andre Danjon's definition of a total penumbral lunar eclipse, only five such eclipses will occur in this century, according to Fred Espenak, an eclipse expert at NASA. The next one comes on Aug. 29, 2053.

So enjoy it. And don't be afraid to look. Lunar eclipses are safe to view. The eclipse starts at 4:21 p.m. Eastern time, about 50 minutes before sunset, on March 14. When the sun sets at 5:14 p.m., you should see the full moon rising in the east. The middle of the eclipse is 6:47 p.m., and it ends by 9:13 p.m., according to Espenak.

Lunar eclipses, like solar eclipses, belong to a centuries-long series. This eclipse comes from a series called Saros 113, which started in April 888 and ends in June 2150, and is No. 63 of 71 in the series. The next lunar eclipse in Saros 113 will be on March 25, 2024.

Also this month, on March 29, there will be a total solar eclipse visible in Africa and Asia. The path of totality crosses through Africa and Asia, with people in Europe able to see only a partial solar eclipse, Espenak says.

Sky Signs of Spring

When evening arrives, find Mars high in the southern sky, while Saturn hangs high in the east. Mars is in the constellation Taurus and the ringed Saturn in the constellation Cancer. Mars becomes a first magnitude object, which means it has dimmed, and Saturn remains at zero magnitude, making it bright enough to be seen from Washington.

Right now Jupiter (negative second magnitude, bright) rises just before midnight; by the end of the month, it will rise in the east at about 9:30 p.m.

Venus, bright as ever at negative fourth magnitude, arrives about two hours before sunrise. At about 4:30 a.m., look for it in the east. By sunrise, you'll find the effervescent Venus shining bright in the southeast.

And the astronomical start of spring occurs at 1:26 p.m. Eastern time, March 20: the Vernal equinox, when the sun crosses the equator from the southern hemisphere into the northern hemisphere.

Down-to-Earth Events

Thursday Curator Frank Winter describes the Pegasus XL launch vehicle, a three-stage rocket dropped from an airplane, in a short lecture. 12:30 p.m., Steven F. Udvar-Hazy Center, Chantilly. 202-633-1000; http://www.nasm.si.edu .

Sunday Astronomer Ke Zhang explains "Exo-planets, the Other Worlds," at the University of Maryland Observatory astronomy open house. View the heavens through a telescope afterward, weather permitting. 8 p.m., U-Md. Observatory, Metzerott Road, College Park. 301-405-6555; http://www.astro.umd.edu/openhouse .