The Sun and the full Moon are like two ends of a seesaw: when one bobs up, the other drops down. It's a motion that's especially obvious the next couple of days and nights, because a full Moon bobs high across the sky.
December's full Moon has a couple of names. One, not surprisingly, is "Moon Before Yule" -- a reference to its appearance just before Christmas. And the other is Long-Night Moon.
At this time of year, Earth's north pole is tipped back away from the Sun. So from the Lower 48 States, the Sun scoots quite low across the southern sky. And it doesn't remain in view for long -- as little as about eight hours from places like Seattle and Boston.
As Earth rotates away from the Sun, though, the Sun's path -- called the ecliptic -- climbs higher in the sky. The Moon and planets follow this same path. And the full Moon is exactly halfway around the ecliptic from the Sun -- like a child on the other end of the seesaw. So when the Sun's half of the seesaw is low in the sky, the Moon's half teeters high -- its highest for the entire year.
And the Moon remains in view longer than any other full Moon of the year -- a good 13 or 14 hours for most of the country, with up to about 16 hours of moonlight from higher latitudes -- lots of cold light for cold nights.
The precise time of the full Moon, by the way, is 10:37 Central Time tomorrow morning, so that gives us tonight and tomorrow night to enjoy a Long-Night Moon.
Script by Damond Benningfield, Copyright 2008
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