Monday, December 4, 2006

Moon Shadows

A brilliant full moon lit the eastern sky last evening and cast deep shadows on our snowy landscape. Such a scene would have been even more spectacular millions of years ago, when the moon was much closer to Earth. Since it formed, the moon has been drifting away from its mother ship, currently at a rate of 4 cm per year!

Modern scientific evidence suggests that the moon formed after the Earth collided with a small planet, some 4.5 billion years ago. This collision ejected a mass of molten debris which coalesced into our lone satellite; the eliptical orbit of the moon, which has an average radius of 240,000 miles, is deflected from the orbital plane of our solar system, lending support to this theory.