The Perseid meteor shower is known as the one not to miss annually. But this year that is truer than ever: With Mother Earth tumbling through the thickest part of the debris stream from Comet Swift-Tuttle, there could be as many as 200 shooting stars per hour during the peak overnight from Thursday August 11 to Friday August 12.
“Forecasters are predicting a Perseid outburst this year with double normal rates on the night of August 11–12,” said Bill Cooke, head of NASA’s Meteoroid Environment Office, in a statement. “Under perfect conditions, rates could soar to 200 meteors per hour.”
We’ve got Jupiter, king of planets, with a gravitational field to match, to thank for that. Even in a typical year, up to 100 meteors are often visible hourly during this shower. This year, astronomers say, Jupiter’s gravitational field has yanked not one, but three years’ worth of debris streams right into Earth’s path, Cooke told Earthsky.org.
“This year Jupiter’s influence has moved the 1079, 1479, and 1862 streams closer to Earth,” he said.
These sand-grain-sized remnants of Comet Swift-Tuttle smash into Earth’s atmosphere at “the blistering speed of 132,000 miles per hour,” as NASA described it. That’s 37 miles per second, Astronomy magazine noted.
“At that speed, even a smidgen of dust makes a vivid streak of light when it collides with Earth’s atmosphere,” NASA said in its statement. “Peak temperatures can reach anywhere from 3,000 to 10,000 degrees Fahrenheit as they speed across the sky.”
The last time the Perseids were this spectacular was in 2009, according to NASA. Comet Swift-Tuttle itself last swooped past the sun in 1992, and it won't be back this way again until 2126, Universetoday.com noted.
“The best views will come in the predawn hours of Friday morning the 12th, after the waxing gibbous Moon sets around 1 a.m. local daylight time,” Astronomy magazine says. “The spectacle will continue to improve as dawn approaches because the shower’s radiant—the spot on the border between the constellations Perseus and Cassiopeia where the meteors appear to emanate from—climbs higher.”
Looking to the northeast will get you to the radiant, though the meteors will be visible all over the sky, said NASA in its statement. And as the constellation Perseus rises—the inspiration for the shower’s name—it will be high in the sky for the 3.5 hours of darkest viewing time between moonset and sunrise.
The cometary source of this atmospheric bombardment—since they burn up 50 miles above the planet, the meteors pose no threat to earthlings—catapults around the sun every 133 years, and its 16-mile-wide nucleus makes it the largest solar system object to pass earth on a regular basis, according to Space.com.
Peak rates last about half a day, said Earthsky.org, but it’s also possible to see Perseids in the days immediately surrounding the peak.
Cloudy skies? Watch the NASA livestream overnight on August 11–12 and August 12–13, beginning at 10 p.m. EDT. But with clear skies, catching this spectacular show is a fairly simple matter of setting the alarm—or staying up way past your bedtime—and finding a place away from city lights, though with this year’s display that isn’t entirely necessary.
“The best way to see the Perseids is to go outside between midnight and dawn on the morning of August 12,” said NASA. “Allow about 45 minutes for your eyes to adjust to the dark. Lie on your back and look straight up.”