Famed Halley’s Comet will not visit us again until 2061, but the remnants of its passage will light up our skies this week with the Orionid meteor shower.
Overnight on Tuesday October 20 and Wednesday October 21, flashes of light will leap out of the club of Orion, in the constellation of the legendary hunter.
“October 20 and 21, 2015 present the probable best nights of the annual Orionid meteor shower,” says Earthsky.org. “And an awesome shower it is!”
“The Orionid meteor shower is not the strongest, but it is one of the most beautiful showers of the year," said Bill Cooke, the head of NASA's Meteoroid Environment Office, in a statement about last year’s version.
From August on, at least one shower a month graces our skies through the end of the year.
“The month of October is about midway through meteor shower season for the northern hemisphere, and one of the annual sure-fire best bets is the Orionid meteor shower,” notes Universe Today, referring to a slew of showers that typically come during fall. November’s got three showers, for instance. Most recent were the Draconids, earlier in October.
The Orionids are more famous for their originating comet than for their brilliance, though they have been known to leave trails as they streak across the sky.
“Although a somewhat modest shower, these swift-moving meteors are sometimes bright, occasionally leaving a persistent train—a glowing streak that lingers momentarily after the meteor has gone!” notes Earthsky.org. Halley’s comet itself last visited Earth in 1986.
They move quickly—about 148,000 miles per hour, according to Space.com.
“Like the springtime Eta Aquarids also generated by Halley’s comet, the Orionids are swift movers, striking the atmosphere at about [41 miles] per second,” Universetoday.com says.
“Speed is important because fast meteors have a tendency to explode,” NASA said in last year’s statement. “Occasionally, Orionid fireballs will leave incandescent streams of debris in their wake that linger for minutes. Such filaments of ‘meteor smoke’ twisted by upper atmospheric winds into convoluted shapes can be even prettier than the meteors themselves.”
While the shower’s official peak is on the night of October 21, plenty will be visible the night before, Earthsky.org says. For glimpsing shooting stars, the usual rules apply.
“The meteors will become visible, starting at late evening, and usually put on their greatest display in the dark hours before dawn on October 21 and 22,” says Earthsky.org. “At the peak, from a dark site, you might expect to see about 10 to 20 meteors per hour.”
The light will be good, since unlike some previous years, the moon is not full, and it will in any case set before midnight on October 20. Stargazing bonus: Venus and Jupiter will glimmer near each other just before dawn.