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This picture shows the surface of Phoebe. There are many large craters on Phoebe's surface. The picture was taken by the Cassini spacecraft in 2004.
Click on image for full size
Image courtesy of NASA/JPL/Space Science Institute.

Phoebe

Phoebe is the name of a medium-sized moon of Saturn. An American astronomer named William Henry Pickering discovered Phoebe in 1898. The name "Phoebe" comes from Greek mythology. In the Greek myths, Phoebe was the daughter of Uranus and Gaia and the grandmother of Apollo and Artemis.

Phoebe has a diameter of 220 km (137 miles). It is the ninth largest of Saturn's moons. The surface of Phoebe is very dark. That is strange. Most of Saturn's moons have bright surfaces. Its dark surface isn't the only strange thing about Phoebe.

Phoebe's orbit around Saturn is also odd. Phoebe orbits much further from Saturn than any of the other medium-sized moons. Also, Phoebe orbits backwards! It moves around Saturn in the opposite direction of most of the other moons.

Why is Phoebe so strange? Many astronomers think Phoebe used to be an asteroid or Kuiper Belt Object. They think Saturn's strong gravity captured Phoebe sometime long ago.

Astronomers want to learn more about Phoebe. Right now, our only pictures of Phoebe are very fuzzy. They were made by Voyager 2 in 1981. Soon we should have much better pictures! The Cassini spacecraft will fly very close past Phoebe on June 11, 2004.

Last modified October 8, 2009 by Randy Russell.

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