Moon and Regulus

The Moon and the star Regulus move across the sky together tonight. Regulus is to the upper right of the Moon as they climb into good view, around 8 or 8:30.

The name “Regulus” means “the little king.” But the star has many other names as well. The most commonly used is Alpha Leonis. It indicates that Regulus is the brightest star of Leo, the lion.

The naming system was created by German astronomer Johannes Bayer, in 1603. He named more than 1400 stars. It was the first systematic naming system for the stars.

Bayer names consist of a Greek or Latin letter, followed by the possessive form of the constellation’s name. Bayer grouped the stars in a constellation by brightness. He had to judge them with his eyes alone, so it wasn’t always easy. The brightest stars got the first letters of the Greek alphabet, so the brightest star of all was usually “alpha,” followed by “beta,” and so on. When the Greek letters were gone, Bayer used the Latin alphabet.

Not every constellation followed this rule, though. In quite a few, the names were bestowed based on a star’s position in the constellation, or some other criteria.

Bayer named only the stars that were visible from Germany and a short distance southward. So many stars in the far southern sky were left out. They were filled in by later astronomers — making sure that every star bright enough to see with the naked eye had its own Bayer designation.
 

Script by Damond Benningfield