Moon and Antares

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A star can have more aliases than a criminal mastermind.

As an example, consider Antares, the brightest star of Scorpius. It rises after midnight tonight, just a whisker away from the Moon. The two remain close together as they scoot low across the south later on.

The name Antares comes from ancient Greece, and it means "rival of Mars." The name indicates that the star looks a lot like the planet Mars -- particularly its reddish-orange color. The name has been around for millennia.

That's not the case for its aliases, though.

The most common is "Alpha Scorpii." It comes from an atlas compiled around 1600 by Johannes Bayer. He used the Greek alphabet to name the stars based on their brightness and their position within each constellation. So "alpha" generally designates a constellation's brightest star.

Most of the other names -- about 35 of them -- come from star catalogs that have been compiled over the last century or so.

Perhaps the best known is the Henry Draper catalog. It's named in honor of an amateur astronomer, and was started in the early 20th century. Today, it includes about 350,000 stars, based on their spectra -- how their light looks when it's split into its individual wavelengths. Antares is designated HD 148478.

In another catalog, Antares in HR 6134, and in yet another, it's SAO 184415. These numbers help astronomers organize the heavens -- though it can be tough to keep up with all the aliases.

Script by Damond Benningfield, Copyright 2008

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