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New planetoid named Sedna discovered
News story originally written on March 17, 2004

Astronomers have discovered a new planetoid at the far edge of our Solar System. The new object, named Sedna, is probably almost as big as the smallest planet, Pluto.

Sedna is very, very far away. It is more than twice as far from the Sun as Pluto, and about 90 times as far from the Sun as Earth. Sedna is probably a huge ball of ice. The ice is reddish in color. There are probably chemicals in the ice that make it red.

Sedna orbits the Sun once every 10,500 years. Its orbit takes it out to about 900 times as far from the Sun as the Earth. Scientists aren't quite sure where Sedna fits in with the rest of the Solar System. It is too far out to be part of the Kuiper Belt, and too close in to be part of the Oort Cloud.

Since Sedna is very cold because it is so far from the Sun, the astronomers who discovered it decided to give it a name from a myth from people who live near the North Pole. Sedna is the name of the sea goddess in Inuit mythology.

Last modified April 6, 2004 by Randy Russell.

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