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An unusually good meteor shower is happening. The reliable summer Perseid meteor shower is unfolding under ideal conditions: A new moon will keep skies ideally black, plus there’s a rare insurance day this time around.
A Weekend Shower
The display usually peaks on a single night, but this year, the spectacle will unfold on both Saturday and Sunday night (August 11 and 12). Of course, those whose location gets buried under clouds won’t see a thing, while the perfect setup would be a Montana-like night with dry air, and not too much haze and humidity.
Shooting stars were once regarded as phenomena in our own atmosphere, which is why we still call weather experts meteorologists. But whether you call them meteors, falling stars, or shooting stars, such “showers” consist of swarms of little comet pieces, each around the size of an apple seed. They orbit the sun in the same path as the comet they came from, which in this case is Swift-Tuttle, a big object discovered in the 1860s.
Comet Swift-Tuttle orbits the Sun backwards, so when we meet its debris, the result is a series of head-on collisions 20 times faster than rifle bullets. And while these ultra-fast meteors can appear anywhere in the sky, they all seem to emanate from a single spot called the radiant, which in this case is in the constellation Perseus. Hence the name of this shower: the Perseids.
Where and When to Look
Perseus rises around 11 PM. That’s why in the first few hours of the night, the meteors all streak upward from below the northeast horizon, where Perseus is located. But after 11 PM or midnight they zoom away from the northeast also going right or left, which is why there’s now more of them. After 2 AM or so, Perseus is high enough that you can even see shooting stars “falling” downward, as well as streaking up, left, or rightward. Thus you see the most then, in the hours before dawn.
If you like meteors—and who doesn’t?—just turn out all the house lights and lie on a blanket or lawn chair facing a large opening to the sky. Being under natural, dark country skies helps a lot. City lights make the background sky so milky, they reduce the number you’d see from one a minute to one every 10 or 15 minutes.
But watch the forecast. You won’t see a thing if the weather doesn’t cooperate.