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Prepare for the Perseids

August is the best month overall to view meteors from the Northern Hemisphere, according to Robert Lunsford, operations manager of the American Meteor Society. And conditions are ideal this year because the Perseid meteor shower peaks on the new-Moon night of Sunday–Monday, August 12–13.

The Perseids are one of the two strongest and most reliable annual meteor showers. (The other is December's Geminids.) And while some showers produce brief bursts lasting just a few hours, the Perseids have a broad peak. So don't despair if clouds are forecast for Sunday night — or if work obligations prevent you from staying up until dawn on Monday. Even now, a week before the peak, you can see up to a dozen Perseids per hour if conditions are perfect. That's stronger than some meteor showers at their best!

The meteor rate increases to roughly 30 per hour in the predawn hours on Saturday, 45 per hour on Sunday morning, and 80 per hour before the sky starts to get light on Monday morning. That's for a single observer at a dark-sky site in the north temperate latitudes.

Perseid meteors are visible in every part of the sky. But wherever you see them, they appear to be moving away from the shower's radiant point near the Perseus/Cassiopeia border. This is a perspective effect, happening for the same reason that snowflakes appear to stream away from the center of the road when you're driving through a snowstorm.

On any given night, activity starts slowly in the evening but picks up by 11 p.m., when the radiant gets reasonably high in the sky. The meteor rate increases steadily through the night as the radiant rises higher, peaking just before the sky starts to get light, roughly 1½ to 2 hours before sunrise.

The Perseid meteors appear to stream away from their radiant near the border of Perseus and Cassiopeia. And while you're outside on a dark night, don't forget to look for the Double Cluster and the Andromeda Galaxy, two of the easiest "faint fuzzies" to spot with your unaided eyes.
S&T Illustration

For the most pleasant viewing experience, find a spot far from any city lights. Perseids tend to be relatively bright as meteors go, but you'll still see more the darker your skies are. Bring a reclining chair so that you can view high in the sky in comfort; there's no point in filling half your field of view with trees. Don't forget warm, mosquito-proof clothes or, better, a sleeping bag. No matter how hot the days are, it can get surprisingly chilly under a clear sky late at night, especially whan you're inactive. And for many people, the most important accessory is bug spray for the parts of you that remain exposed!

It doesn't really matter where in the sky you watch; meteors can appear anywhere. Just watch where it's darkest, usually straight up. It's probably best not to stare directly at the radiant, because meteors there leave short trails.

Keep track of the direction each meteor is moving. Though most will be Perseids, you'll probably see plenty of Delta Aquarids moving more or less in the opposite direction. And this time of year is also good for sporadic meteors not associated with any recognized shower.

More on meteors and how to observe them — including how to make a scientific count to report to the International Meteor Organization — is in our meteor section.