A Fresh Shower
Several well-known meteor showers light up the night sky every year. But quite a few minor showers have also been recorded — including one that was discovered one year ago today.
A network of skywatching cameras in California recorded a half-dozen bright meteors that were all coming from the same direction in the sky — from near a star in the northern constellation Draco, the dragon. The shower has been designated for that star — the February Eta Draconids.
A meteor shower takes place when Earth passes through the orbital path of a comet or asteroid. These objects shed small bits of rock and dust as they orbit the Sun. The particles spread out along the object’s path, forming a long stream. When Earth passes through such a stream, some of the particles plunge into the atmosphere, forming the glowing streaks known as meteors.
The February Eta Draconids probably came from a comet on a long, stretched-out orbit. The gravity of Jupiter and Saturn pushes around the stream of debris, so sometimes it intersects Earth’s orbit. Such encounters appear to be rare, though — there won’t be a shower this year, and probably not for at least several years, if not decades.
The parent comet hasn’t yet been seen — and the astronomers who operate the camera system say that could be a problem. Since the comet’s orbit intersects Earth’s orbit, it could one day hit our planet — causing much worse than a sprinkling of meteors in the night sky.
Script by Damond Benningfield, Copyright 2011
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