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Dark Nights for the Perseids
The shower lasts for many days, but according to the International Meteor Organization this year's peakshould occur during a half-day-long window centered on 1:00 UniversalTime on August 13th, which is ideal timing for skywatchers in Eurasia.For North Americans, the best viewing will probably be late Thursdaynight and early Friday morning, August 12-13, or possibly the nightbefore.
In any case, prime viewing for the Perseids is from about11 p.m. or midnight (local time) until the first light of dawn. This iswhen the shower's radiant (its perspective point of origin) is well up in your sky. The higher the radiant, the more meteors you'll see.
At a very dark,rural site, you can probably expect to see 100 or more meteors per hourwhen the radiant (in northern Perseus) is highest in your sky before thefirst light of dawn. Any light pollution will cut down on the numbers,as will the radiant's lower altitude earlier in the night. But thebrightest few meteors shine right through light pollution, and the fewthat happen when the radiant is low are especially long, skimming theupper atmosphere and flying far across the sky.
To get the mostenjoyment while watching for Perseids, find a dark spot with an open skyview, bundle up thoroughly in blankets or a sleeping bag (for mosquitoshielding as well as warmth, and don't forget the repellent), and lieback in a reclining chair. Gaze into the stars, and be patient. The bestdirection to watch is wherever your sky is darkest, usually straightup, perhaps with a little inclination toward the radiant. That's allthere is to it!
Notall the meteors you'll see are Perseids. In addition to occasionalrandom, sporadic meteors, the weaker Delta Aquarid shower is also activeduring Perseid season. The Delta Aquarids are slower, often yellower,and track away from a radiant point in eastern Aquarius. Weaker stillare the Kappa Cygnids, identifiable by their flight direction away fromCygnus in an altogether different part of the sky.
Don't forgetthat the Perseid shower lasts for more than one night! Rates are about aquarter to half the peak for one or two nights before and after. A fewforerunners of the shower may show up as early as July 20th, andstragglers have been recorded as late as August 24th.
Posted by Alan MacRobert, July 27, 2010related content: Celestial events