Crater

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The old adage about not judging a book by its cover applies to the stars as well: Don't judge a star by how bright it looks. Almost every one of these little points of light is actually far more impressive than our own star, the Sun.

Consider the stars of the constellation Crater, the cup, which dribbles across the south on spring nights. Eight stars outline the cup, but they're so faint that you need a pretty dark sky to see any of them.

That's only because they're a long way off, though. The closest member of the octet is about 85 light-years away. From that same distance, the Sun would be too faint to see at all.

As seen from Earth, the brightest of the bunch is Delta Crateris, which is almost 200 light-years away. It's an orange giant -- a star that's puffed up as it nears the end of its life. It's about 20 times wider than the Sun, and about a hundred times brighter.

The second-brightest is Alpha Crateris. Like Delta, it's also an orange giant. It's a little smaller, though, so it shines only about half as bright.

The other stars that outline the cup include two more giants, plus four stars that aren't giants but that are much hotter than the Sun, and up to about 250 times brighter.

Because they're so far away, though, you need a dark sky to see these stars. They're in the southeast at nightfall, well to the right of a line formed by the two brightest points of light in that part of the sky: the star Spica and the planet Saturn.

Script by Damond Benningfield, Copyright 2010

For more skywatching tips, astronomy news, and much more, read StarDate magazine.