Geminid meteor shower takes the stage
CAPE CANAVERAL, Fla. — It's time for the December sky show.
Those willing to endure the cold and stay up past their bedtimes are about to be treated to the annual Geminid meteor shower.
This year's shower will begin to peak just after midnight Thursday and last through dawn. Then it will be back Friday night into the predawn hours of Saturday. Falling stars should be visible beginning mid-to-late evening and ending at dawn both nights.
The shower, whose origins are mysterious, will be partly obscured by a waxing moon, but those who venture into the cold should be rewarded by seeing at least a few shooting stars, astronomers say.
The meteors will start few and far between in early evening but will increase in number as evening deepens into late night. Worldwide, these meteors will fall most abundantly in the hours after midnight, with the largest concentration at 2 a.m. EST.
“Meteor showers have personalities,” said Deborah Byrd, editor in chief of EarthSky.org, a science and astronomy site based in Austin. “The Geminids tend to be bright and they tend to be white, so they can withstand a fair amount of moonlight.”
The best way to see them “is to go to sleep for a few hours and then get up around 2 a.m.,” Byrd said.
The moon begins to slowly set about that time and will be fully down by 4 a.m. wherever the watcher is in North America.
“As the moon gets lower in the sky, it's going to be easier to see the meteors,” she said. Standing in the shadow of a building to block the moon's light will also help. The light of the moon resets the eyes and makes it harder to see faint objects.
The moon is in its waxing phase and will be gibbous (more than half full) and up most of the night, so its light will compete with fainter meteors.
The Geminids get their name because they appear to emerge from the constellation Gemini. They're not actually coming from that group of stars, but it appears that way from the Earth.
The Geminid is one of the best meteor showers of the year, usually producing upwards of 50 falling stars an hour when there's no moon. Even with the moon's light interfering this year, a good number of meteors should be visible.
Meteor showers in general are caused when Earth passes through the dust trail left behind by a comet. “The dust bits burn up in the Earth's atmosphere as we plow through the cloud,” said Benjamin Burress, an astronomer at the Chabot Space & Science Center in Oakland, Calif.
The Geminids “are specks of debris from 3200 Phaethon, which is not a comet, as you might expect, but an asteroid,” said Rick Kline of the Planetary Imaging Facility at Cornell University in Ithaca, N.Y.
The asteroid is “a mysterious type of object sometimes called a “rock comet,” Burress said. Astronomers don't quite understand how or why an asteroid is producing a comet-like stream of dust.
The shower actually lasts for longer than just two nights, said Ron Hipschman, a scientist at the Exploratorium, a science museum in San Francisco. “We actually run through the dust trail of 3200 Phaethon from Dec. 4 to Dec. 17.”
The portion of the trail the Earth will be going through is densest from Dec. 12-14, so that's when the most meteors will be visible.