In between the kuiper belt and the Orrot cloud.
The planet Sedna is not actually a planet, just a small lump of ice and rock. In fact Pluto, the ninth planet in our solar system, has just been downgraded and is no longer considered a...
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The discovery team; by Mike Brown, Chad Trujillo and David Rabinowitz named Sedna, which was discovered on November 14, 2003.
Sedna is so far from the Sun that the temperature never rises above 33 kelvin (−240 °C; −400 °F).