Moon and Regulus

StarDate: January 12, 2009

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Marching toward the jaws of a lion is generally not a good idea. But the Moon does it every month, as it takes aim at the constellation Leo. In fact, it's doing that tonight. Leo's brightest star, Regulus, is a little below the Moon as they rise in mid evening. The rest of Leo spreads out below and to the left of Regulus.

Regulus itself represents the lion's heart. But it's at the tip of a pattern of stars that forms the lion's head and mane. This pattern looks like a backwards question mark, known as the Sickle.

The star that's closest to Regulus, at the bottom of the question mark's curve, is Algieba -- a name that means "the forehead." It's actually a double star -- two stars that are locked in a mutual orbit. Both stars are giants, which means they're much larger and brighter than the Sun, and later in life. One of the stars is a little cooler than the other, so it looks orange, while the other looks yellow.

Three other giant stars complete the Sickle: Adhafera, which means "the lock of hair;" Rasalas, the "northern" star, which refers to its position in the Sickle; and Algenubi, the southern star. Although they don't look as bright as Regulus, they're fairly easy to see because the shape of the Sickle stands out.

The Moon never quite heads straight into the Sickle, though. Its path stays close to Regulus. So while it moves toward the jaws of the lion every month, it always stays just out of reach.

Script by Damond Benningfield, Copyright 2008

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