Fire in the Sky
The Geminids light up the night
The waxing crescent moon sets early at week’s end, leaving a dark backdrop for this year’s Geminid meteor shower, which peaks between nightfall Thursday the 13th and daybreak the following morning.
The Geminids are one of the best meteor showers. This year, with clear skies and a little luck, they should be especially prolific, with 60 to 120 meteors an hour, depending on how dark your vantage point is. Not only does the moon set by 8:30 Thursday night, but the parent of the meteors the asteroid 3200 Phaethon passes just 11 million miles from Earth a few days earlier, providing a fresh stream of debris to fuel the pyrotechnics.
As Earth passes through this trail of stellar debris, it is bombarded with bits of ice and rock, which ignite upon contact with our atmosphere. Most of these meteors burn up well before entering the atmosphere; those that reach earth are called meteorites.
Other meteor showers result from icy comets orbiting our sun. The asteroid Phaethon, however, is a huge chunk of rock, slowly dwindling as it circles the sun. Some astronomers believe that it may once have been a comet, but that over countless millennia it lost its corona, its tail and much of of its bulk, leaving only a dead nucleus.
Also, whereas records of other meteors stretch deep into history, the Geminids were first reported in 1862. Astronomers spent more than 100 years looking for the parent comet, finally discovering Phaethon in 1983.
The Geminids begin at sunset with the rising of Gemini, from which the meteors appear to emanate. But the real show begins later, when the constellation is high overhead. While waiting for meteors, enjoy ruddy Mars, right at the center of it all.
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