The gibbous Moon pushes through a ring of stars tonight — a wide ring known as the Winter Circle. The Moon is about half-way between Procyon, the brightest star of the little dog, and Pollux and Castor, the “twin” stars of Gemini.
The Winter Circle is one of the largest asterisms in the night sky — a pattern of stars that doesn’t form a constellation. Indeed, the Winter Circle incorporates stars from six constellations, most of which form their own distinctive pictures. And it spans a huge swath of the sky — about six times the width of your fist held at arm’s length.
At the center of the circle is orange Betelgeuse, one of the brightest stars of Orion, which forms one of the most easily recognizable pictures in the night sky.
At the bottom of the circle is Sirius, the brightest star in all the night sky. It’s part of the constellation known as the big dog. And to the upper right of Betelgeuse is Aldebaran, which forms part of the V-shaped face of Taurus, the bull.
The patterns that flank the Moon are a bit tougher to identify. The little dog looks more like a doggy toy — a stick outlined by just two stars. And while it’s easy to make out Pollux and Castor, which represent the heads of the twins, it takes a little more effort to make out their bodies.
The Winter Circle is in fine view as darkness falls, and wheels even higher across the sky during the evening. It begins to drop from sight by around 2 o’clock in the morning.
Script by Damond Benningfield, Copyright 2011
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