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Capricornus

StarDate: 
October 9, 2018

Despite its fame as a member of the zodiac, Capricornus is a bit tough to find. It’s the smallest member of the zodiac, and one of the faintest. It forms a distinctive pattern, though — like the bottom of a bikini bathing suit. So under dark skies, you can pick it out.

The constellation represents a sea-goat. In Greek mythology, though, it was associated with the god Pan. During a battle with the Titans, he had to jump into the Nile to escape. When he did, the bottom half of his body was transformed into a goat.

The brightest star in Capricornus is Deneb Algedi — “the tail of the goat.” It’s a system of at least two stars, and perhaps as many as four.

The main star is about twice as big and heavy as the Sun, and about eight times brighter. It’s at the end of its “normal” lifetime, so it’s puffing up. So someday, it’ll be much bigger and brighter than it is now.

The star has a close companion — so close that the two stars blur together. Astronomers have to use special instruments to study it.

Two more stars appear close to this pair. All of the stars may be bound to each other. On the other hand, the two outliers may simply line up in the same direction as Deneb Algedi, and aren’t related to the sea-goat’s most prominent star.

This is a good time to look for Capricornus, because there’s no Moon in the sky, and the bright orange planet Mars is passing through the constellation. They’re in the south at nightfall.

More about Capricornus tomorrow.


Script by Damond Benningfield

 

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