for National Geographic News
The Geminid meteor shower—considered by many to be the most active annual sky show—is going to be especially spectacular this year, astronomers predict.
The show gets its name from the constellation Gemini, because the meteors appear to stream from near the constellation's bright star Castor.
Unlike last year, the Geminids will be falling against a dark, moonless night.
The last time the sky was this dark during the shower was in 1996, when observers saw up to 110 meteors an hour.
Experts say the rate will be at least that high this year, with peak viewing on December 13 and 14.
"Since the August Perseid shower has been declining the last couple of decades, the Geminids are now the best annual meteor shower," said Brian Skiff, a researcher at Lowell Observatory in Flagstaff, Arizona.
(Related: "Perseid Meteor Shower to Peak This Weekend" [August 10, 2007].)
And this year the meteors will be joined by an exceptionally bright Mars visible in Gemini. The planet will be gleaming yellow-orange as it nears a close approach to Earth.
Most annual meteor showers occur when Earth passes through fields of debris left behind by orbiting comets. Researchers can therefore tie a particular shower to a known comet.
Although the Geminids were first noticed in the mid-1800s, scientists didn't locate their source until 1983.
Co-discoverers Simon Green, now at the Open University in the United Kingdom, and John Davies, now at the Royal Observatory in Edinburgh, pinned the yearly show to a mysterious object called 3200 Phaethon.
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