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The annual Perseid meteor shower is underway and will reach its peak activity in the coming days, offering an opportunity to just sit outside at night and watch shooting stars. NPR's Nell Greenfieldboyce on what you'll see and how to get the best view.
NELL GREENFIELDBOYCE, BYLINE: The Earth is constantly moving through space, orbiting the sun, and every summer, our planet plows through a bunch of debris left behind by a comet, a big ice ball called Comet Swift-Tuttle. Peter Brown is a meteor researcher with the University of Western Ontario. He says bits of rock and dust from this comet hit our atmosphere going really fast - over 100,000 miles per hour.
PETER BROWN: And because it hits so fast, we can see very tiny particles.
GREENFIELDBOYCE: A particle the size of, say, a grain of sand will slam into the upper atmosphere. This heats the little particle up, atoms boil off, and those atoms go on to have their own collisions.
BROWN: So when you have two atoms slamming together tens of kilometers a second, you get a whole bunch of things that are produced - you get electrons, ions, and you excite the atoms, and they produce light.
GREENFIELDBOYCE: A streak of light so bright, it can be seen from many miles away. He says, an incoming pebble that weighs about as much as a paper clip can look brighter than the planet Venus. And when the Perseid shower peaks on the night of August 11, going into August 12...
BROWN: You might see a handful of those - three, four, five of those - an hour.
GREENFIELDBOYCE: Plus fainter ones, too. And if you're lucky, maybe something bigger and brighter, a real fireball. Brown says with some other meteor showers, if you miss the peak, you're out of luck, but not so with the Perseids.
BROWN: The Perseids are so large, and they're so spread out that you can see them within a day or two of the peak, and you still see a really impressive show.
GREENFIELDBOYCE: So if you're busy or there's clouds, try another night. The best view will come under really dark skies without light pollution or the moon. Hunter Miller is a public observing educator at the Adler Planetarium in Chicago.
HUNTER MILLER: The later you're out, the more dark the skies will get as the moon sets, and starting, like, past midnight, you'll have a pretty nice dark sky.
GREENFIELDBOYCE: He says, grab a lawn chair or a blanket and find a spot with as big a view of the sky as you can get. Look northward. Your eyes have to adjust to the darkness. So it's best to sit out for at least 30 minutes without peeking at your phone.
MILLER: You can use your phone to, you know, find the location you need to look to in the sky, but then keep them away because it really can, you know, basically mess up all of the time that you spent trying to let your eyes get dark adjusted.
GREENFIELDBOYCE: He says, a lot of time, you look up in the sky, and it feels eternal. But a shooting star only lasts a couple seconds. That's part of its appeal.
MILLER: It feels like you saw something really special and personal.
GREENFIELDBOYCE: And the Perseids are one of your best chances all year to see one.
Nell Greenfieldboyce, NPR News. Transcript provided by NPR, Copyright NPR.
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