Sky Watch

Venus and Saturn Star in August Sky

By Blaine P. Friedlander Jr.
Special to The Washington Post
Sunday, July 30, 2006; Page C02

Wane worlds: Venus and Saturn will meet in a low-profile fling as August wanes, while a waning gibbous moon washes out many of the upcoming Perseid meteors.

Just after the full moon Aug. 9, sky gazers can enjoy the peak of the annual Perseid meteor shower on the night and early morning of Aug. 12 and 13. The Perseids -- so named because they appear to emanate from the constellation Perseus -- are best found just before midnight and into the morning hours, rising in the northeastern sky.

This year's shower has a catch: The moon will wash out all but the brightest of the shooting stars. Barring cloudy skies, persistent Perseid watchers likely will observe a few meteors despite that pesky moon.

Meteor showers occur when the Earth passes through the dusty trail of a long-gone comet, in this case Comet Swift-Tuttle , which was discovered in 1862. Tiny pieces of trail dirt strike the Earth's atmosphere, burn up and create impressive glowing streaks.

For predawn beachcombers and early-morning sky gazers, count on action. Mercury , Saturn and Venus populate the eastern horizon before sunrise.

Just before the middle of August, Mercury (zero magnitude, bright) is high enough above the eastern horizon in the morning sky to be visible before sunrise. The trouble with Mercury is that it never stays high for long. This could be a good visit, if you can see it from an unfettered horizon at the beach.

Mercury and Venus (negative third magnitude, very bright) get close in the middle of the month, leading to the picturesque morning of Aug. 22 when Mercury, Saturn, Venus and the ultra-thin crescent moon crowd the eastern sky.

But which planet is which? If looking east Aug. 22, Venus will be the brightest and top planet, Saturn (zero magnitude, bright) will be below Venus and Mercury will be at the bottom. Four days later, Venus and Saturn conjunct on the morning of Aug. 26.

Among the visible planets, Jupiter stars at night. As grill embers cool, look high in the south-southwestern sky to find Jupiter (negative first magnitude, very bright) at dusk. It's the brightest object in that part of the sky. The king of the planets gives sky gazers a summer treat, and it sets at midnight now.

As August lingers, watch Jupiter move closer to the western horizon. From mid-August to month's end, this big, gaseous planet sets in the west about 11 p.m.

Down-to-Earth Events

Aug. 5 -- Astronomer Greg Redfern explains "A Cosmic Detective Story: The Chesapeake Bay Impact Crater," at the University of Maryland Observatory's open house in College Park. See the heavens through a telescope after the lecture, weather permitting. 9 p.m. Information: 301-405-6555 or www.astro.umd.edu/openhouse.

Aug. 20 -- Matthew Burger of NASA discusses "The Cassini-Huygens Mission to Saturn and the Ice Volcanoes of [the Saturn moon] Enceladus." The lecture will be at the University of Maryland Observatory's open house in College Park. After the lecture, see the night sky via telescope, weather permitting. 9 p.m. Information: 301-405-6555 or www.astro.umd.edu/openhouse.

Aug. 26 -- Join Sean O'Brien of the National Air and Space Museum for a Saturday Star Party at Sky Meadows State Park near Paris, Va., from 8:30 to 11 p.m. Parking costs $4. Information: 540-592-3556 or http://www.dcr.virginia.gov/state-parks/sky-meadows .

Aug. 26 -- The National Park Service and the National Capital Astronomers host "Exploring the Sky" at Rock Creek Park, near the Nature Center, in the field south of Military and Glover roads NW, 9 p.m. Information 202-895-6070, http://nps.gov/rocr http:// or http://capitalastronomers.org .

Blaine Friedlander can be reached at PostSkyWatch[at]aol[dot]com.

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