Geminid Meteor Shower 2012: Shooting Stars Peak Thursday
(WASHINGTON) -- You may want to stay up late Thursday or get up early in the morning. The Geminid meteor shower peaks Thursday night -- usually one of the best of the year, and early indications are that it's already putting on a good show.
Earth is passing through the orbit of an asteroid called 3200 Phaethon, and astronomers think we're seeing its debris -- shooting stars, more than 50 per hour, many of them no larger than grains of sand, burning up as they plow into the atmosphere.
Astronomers say it's worth watching after 9 or 10 p.m. local time, and the seeing gets better after midnight, since the morning side of the Earth is the one that faces forward as we travel around the sun. Conveniently, there's a new moon -- nothing bright in the night sky to blind you to the sometimes-faint shooting stars.
The Geminids, which happen this time of year like clockwork, are an oddity. Most major meteor showers -- the Perseids in August, the Leonids in November -- have occurred for thousands of years, caused as Earth passes through clouds of debris left by passing comets.
But the Geminids only appeared in the 1860s. Not until 1983 did astronomers find 3200 Phaethon, in a lopsided orbit that crosses our own and also brings it close to the sun -- close enough, they theorize, that the sun's heat cracks it and kicks up dust, which, over time, has spread out along the asteroid's path.
Copyright 2012 ABC News Radio