The winter clock

Many people live under the mistaken belief that they cannot learn to recognize constellations. They may recall looking up on some clear summer night in their past and feeling overwhelmed by the thousands of points of light that seem scattered randomly across the sky. But the stars are, in fact, quite easy to learn if you use their constant positions as pointers to other stars and star groups.

In the Northern Hemisphere, if you go outside this week around 9

12 o'clock





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Castor w /

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Procyon ■

Rigel /

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6 o'clock

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1 The 'winter clock,' facing south-southeast, 9 p.m., January 23. 1

o'clock and face south-southeast, you will see the hard-to-miss constellation Orion the Hunter. You know you're looking at Orion when you see three stars of the same brightness lying next to each other in a distinctive row stretching southeast to northwest. This line of stars represents the hunter's belt. The belt itself is framed within four stars, two of exceptional brightness that are diagonally opposite one another. The smoldering red star at the upper left of the belt, marking one of the Hunter's shoulders, is Betelgeuse.

If you stand back and take in this grand canvas of sky, you'll notice that red Betelgeuse lies near the center of an oval ring of bright winter stars that occupies the entire southeastern quadrant of the sky. This huge asterism is sometimes referred to as the 'winter circle' or 'winter hexagon,' but it can just as easily be considered a kind of giant starry clock, with Betelgeuse being the clock's centerpoint and the region's brightest stars consigned to certain hours.

We'll assign the 6 o'clock position to the brightest star visible in the entire night sky, dazzling white Sirius in Canis Major. Orion's belt conveniently points to Sirius, though it is so bright it is difficult to misiden-tify with other stars. At the 8 o'clock position, then, lies Procyon, a bright creamy yellow star in Canis Minor (the Lesser Dog). About 4° to the northwest is Gomeisa, or Beta (P) Canis Minoris, a magnitude 3 star. A simple line between these two stars is all that makes up the pattern of this humble constellation.

Snugged between the 9 and 10 o'clock positions, respectively, are two stars of almost equal brightness: Pollux and Castor. These stars mark the heads of Gemini the Twins. The northernmost star, Castor, is white, while Pollux is orange.

At nearly the 12 o'clock position, and thus high overhead, is Capella, a yellow star located in the pentagonal constellation Auriga the Charioteer. Dropping down to about 1 o'clock we see red Aldebaran, the bright, angry eye in the triangular face of Taurus the Bull. Completing the circuit is blue-white Rigel, at 4 o'clock.

Do you see any other fixed 'stars' as bright as these shining above Orion in the swath of sky between 8 and 1 o'clock? If so, you're seeing Mars, Jupiter, or Saturn. These bright planets move along the ecliptic path, which runs north of Orion through Gemini and Taurus, and often appear as 'guests' in the winter circle.

As the night progresses and these constellations shift to the west, the clock face lists a bit - forcing you to tilt your head a little to orient yourself to the clock face. Just remember that Sirius always marks the six o'clock position. That way, the winter clock can make an excellent reference with which to familiarize yourself with this area of the night sky, no matter what time you look at it.

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