Chi 1 Orionis

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• 11 of 1971
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The spectacular constellation Orion is in the southeast in early evening, and due south later on. Orion owes its splendor to big, bright, far-away stars -- stars like Rigel and Betelgeuse, and the three stars of Orion's Belt. But Orion is also home to a fainter, nearby star that's almost an exact duplicate of the Sun.

The star is called Chi 1 Orionis, and it's just 28 light-years away. Like the Sun, it's classified as type G, meaning it's warm and yellow. Chi 1 is about the same brightness as the Sun, too.

The Sun itself shines on at least one life-bearing planet -- Earth -- raising the hope that Chi 1 Orionis also has planets -- and life.

But there are two big problems.

First, the star has a companion star, about 15 percent as massive as the Sun. They're about as far apart as Jupiter is from the Sun. They orbit each other once every 14 years. The gravity of the companion could have prevented gas and dust around the star from coming together to form planets.

In addition, Chi 1 Orionis is young -- perhaps only a hundred million years old. So even if it does have Earth-like planets, life may not have had time to take hold around this intriguing stellar neighbor.

To find Chi 1, first find Mars, which looks like a bright orange star high in the east early this evening. Then look to its south for another orange pinpoint -- the star Betelgeuse. Chi 1 is along this line, a little closer to Mars. Binoculars will help you pick it out.

Script by Ken Croswell, Copyright 2007

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