Company for the Moon

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The moon has lots of stars for company at night, but it's still the only moon we have.  Scientists are now predicting that the earth may someday collect another moon.  Mind you, as moons go, it won't be much to brag about.  Besides it will not stay around for long.

An asteroid, about the size that would fit into a large football stadium, is expected to orbit around the earth for about forty years.  Then it will press on in its usual orbit around the sun.  This recently discovered asteroid is unique because it's the first found to revolve around the sun in nearly the same path as the earth.

It appears that the asteroid is playing a cat and mouse game with the earth.  First it approaches us on one side and then the other.  In January 2003, the asteroid was at its closest point to the earth in nearly a century.  Not that you need to be concerned about it, since it was still nearly six million kilometres away.  Right now it's scurrying off again into space.  But because of the combined gravity of the earth and the sun, it will catch up again in about ninety-five years.  The scene is like two cars racing on a circular track.  Right now we are catching up to it.  But when we finally get close, the gravitational effects of the earth and the sun will nudge the asteroid into our track and it will join us for a while.

So next time you look at the lonely moon, remember some day it will have a little buddy, at least for a while.