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Moon and More Companions

March 19, 2014

The Moon takes dead aim at a star with one of the best names in all the sky in the wee hours of tomorrow morning. Zubenelgenubi is a little below the Moon as they climb into good view after midnight, and quite close to the left of the Moon at first light.

Zubenelgenubi is the brightest star of the present-day constellation Libra. But its intriguing name comes from an Arabic phrase that means “the southern claw.” That tells us that the star once represented one of the claws of nearby Scorpius.

The classical constellations are connect-the-dots pictures that link some of the brightest stars in a given region of the sky.

Quite a few cultures have seen the stars of Scorpius as a scorpion — a curving line of stars with a hooked end, like a stinger, and a band of stars on the other end, like a head. And thousands of years ago, skywatchers also saw a couple of stars as the scorpion’s claws — Zubenelgenubi and its nearby cousin, Zubeneschamali.

Centuries later, though, the claws were severed from the scorpion and given to the new constellation Libra, which represents a balance scale. That may have been because the Sun appeared against those stars at the time of the fall equinox — a time of equal daylight and darkness — a time of balance in the sky.

Watch for Zubenelgenubi as the Moon creeps toward it in the wee hours of the morning. Another bright object is close to their upper left at first light — the golden planet Saturn.


Script by Damond Benningfield, Copyright 2014

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