Mental Floss

Look Up! The Perseid Meteor Shower Is Back, and It'll Be Amazing This Year

By David W Brown

NASA/JPL
NASA/JPL / NASA/JPL
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This week the Perseid meteor shower will peak, and even if you're ordinarily lousy at spotting these sorts of things, there's a good chance you'll be able to catch at least a few shooting stars. Why? Because the night sky might produce 150 to 200 meteors per hour! This is the best meteor shower of the year, and the best showing of the Perseids in two decades. So what is going on up there?

COMET SWIFT-TUTTLE'S LOSS IS YOUR GAIN 

As they travel, comets leave behind trillions of dust- and sand-sized particles. When the Earth crosses into the debris trail of a comet, those particles slam into the atmosphere at tens of thousands of miles per hour, producing the "shooting star" effect as they burn up.

Comet Swift-Tuttle is the source of the Perseid shower, so named for the constellation from which it seems to originate. The comet orbits the Sun every 133 years, and what you see when you're looking at this meteor shower are particles left behind centuries ago. Ordinarily, the Earth passes through the periphery of the field of debris. This time, thanks to orbital dynamics, we'll be passing much closer to the heart of things. Jupiter's gravity has tightened the trail of particles into a particularly dense debris field. That makes this an "outburst" year, doubling the number of possible meteors per hour. If ever you've wanted to try your hand at astrophotography, this is your big chance.

HOW TO CATCH THE SHOW

You don't need much to catch a meteor shower. (A blanket, primarily. Maybe a chair.) The real issue is what you must avoid in order to see the show. And that is light pollution. It is the enemy of the night sky. It is produced by ambient lighting and such things as poorly oriented lampposts, which sometimes point out and up in addition to down, where the light is actually needed.

For the best show possible, you're probably going to want to get out of town if you live in a highly populated area. The simple act of driving to the countryside can triple the number of visible meteors. If the evening sky is clear and your surroundings are dark, all you need to do is look up and wait. (That's where the blanket comes in handy.) It takes about 45 minutes for your eyes to adjust to the darkness. The best night to see the Perseids will be after midnight and before dawn on the morning of August 12, when the Earth passes through the densest part of the debris field. 

If it's rainy where you are, don't fret. You can already see some of the Perseids at night now, and you'll still be able to catch meteors after the shower's peak, through August 26. If the weather is really working against you, NASA's Marshall Space Flight Center, home to the Meteoroid Environments Office, will be livestreaming the event at 10:00 p.m. EDT on August 11 and 12.