Get ready to make plenty of wishes for the holiday season, as the annual Geminid meteor shower peaks on the nights of December 13 and 14 under nearly ideal conditions, delivering a flurry of shooting stars. (Check out some of the other must-see sky shows in December.)
The Geminids are among the strongest and most reliable sky shows, even at times besting August's famed Perseid meteor shower. This year’s show promises to be especially exciting: With the waxing crescent moon setting between 10 and 11 p.m. local time, deep darkness in the late-night hours should allow stargazers to catch dozens of meteors dashing across the skies.
The official peak of the Geminids occurs around 7:30 a.m. ET (4:30 a.m. PT) on December 14, so observers across the Pacific Basin and North America will be able to observe the most meteors in their overnight hours on those dates. Meteors should fall at rates of anywhere from 20 to 100 an hour on both dates, assuming clouds and weather permit a glimpse of the celestial fireworks.
Where do the Geminids come from?
With all the cold, wintery weather across the Northern Hemisphere this time of year, it’s not surprising that the Geminids have historically been snubbed by most sky-watchers. But that is beginning to change thanks to their rising intensity in recent decades.
Back in 1862, people watching the Geminids reported seeing fewer than 20 shooting stars an hour. Since then, rates have skyrocketed to well over a hundred a night in some years, particularly when the skies are moonless during the peak.
What’s the reason for the uptick? Astronomers believe that Earth is plowing deeper every year into the ancient stream of debris that gives rise to the meteor shower.
Most annual showers happen when our planet slams into debris shed by comets. As these objects near the sun, their ices vaporize and they release rocky material that gets trapped in their orbital paths. When Earth crosses these debris streams, the sand grain-size to boulder-size chunks of comet burn up in our atmosphere, creating the dazzling light show. (See pictures of Geminid meteors.)
But the Geminids are somewhat mysterious, as no comet can be linked to their debris stream. Instead, astronomers think the Geminids come from a strange asteroid–comet hybrid called 3200 Phaethon. Discovered in 1983 in data from a NASA satellite, the three-mile-wide space rock has an orbit that matches neatly with the annual arrival of the Geminids, making it a prime candidate for the source of the meteor shower.
When is the best time to watch the Geminids?
The shower's radiant—the point in the sky from which the meteors appear to originate—is its namesake constellation Gemini, which will rise above the eastern horizon after 9 p.m. local time.
This year, observers should head outside once the moon has set, as that’s when more of the fainter meteors should start to become visible. Meteor shower activity will then have a definite uptick in the predawn hours, because Earth is rotating toward the sun and thus is swallowing up more of the debris stream at that time.
The Geminids are fun to watch because they last a bit longer than other meteors streaking across our skies. They hit the atmosphere at around 20 miles a second, creating beautiful, long trains across the sky—many lasting a relatively luxurious second or two.
Where can I see the Geminids?
Due to the orbit of the shower's parent object, the Geminids are primarily a Northern Hemisphere sky show, and the best views will be in North America.
People in Europe and Africa will be able to see the show just ahead of and after the peak, with the sky show beginning late Thursday night and continuing into the predawn hours of Friday, then picking up again on Friday after local nightfall. Sky-watchers in the Southern Hemisphere will be able to observe the shower, but it won't be as brilliant.
For the best views, meteor-watchers should head to the dark countryside far from bright city lights. But keen-eyed suburbanites should get to see at least some of the biggest and brightest meteors zipping across the sky at rates of around one shooting star every three minutes or so.
No matter where you are, no special equipment is necessary to enjoy the show. This type of sky event is best seen without a telescope or binoculars, since meteors race across large tracts of the sky too fast to focus on them. Just be sure to stay warm, allow your eyes a chance to adjust to the dark, and look up.
Happy meteor hunting!