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Moon and Companions

March 17, 2013

The Moon slides between two bright companions this evening - the planet Jupiter and the star Aldebaran, the “eye” of Taurus, the bull. They’re in grand view as night falls, and set in the wee hours of the morning.

If you keep an eye on them during that period, you’ll get a good illustration of how quickly the Moon moves across the sky.

It takes four weeks for the Moon to circle through the background of stars. So from one night to the next, the Moon moves a little more than the width of your fist held at arm’s length. That’s a pretty good distance, but it’s hard to see it during the night because there aren’t always bright stars or planets around to measure the Moon against.

Tonight, though, there are two good markers. Jupiter is by far the brighter of the two. In fact, after the Moon itself, it’s the brightest object in the evening sky right now. Aldebaran is only a few percent as bright, but it’s still one of the brightest true stars, so you won’t have any trouble finding it.

The exact Moon-Jupiter-Aldebaran configuration depends on your location. But the trio will remain in view for several hours after sunset. During that time, the Moon will move about six times its own diameter. With the other bright objects so close by, that distance is pretty obvious to even the most casual of skywatchers. So if you have the chance, keep tabs on the Moon throughout the evening, as it continues its eternal eastward slide across the sky.


Script by Damond Benningfield, Copyright 2013

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