Object 90377 Sedna — a distant trans-Neptunian object known best for its highly elliptical, 11,390-year-long orbit — is currently on its way towards perihelion (its closest approach to the Sun) in ...

Scientists have been wondering for years whether there is a ninth planet in our solar system. Now, a study by Japanese scientists seems to bust that belief. They have found an object orbiting the Sun ...

Venture into the extreme outer reaches of the solar system to explore the most distant and enigmatic bodies ever discovered. Meet Sedna, Gong Gong, and Eris as we investigate their strange orbits, ...

Scientists think there may be a ninth planet hiding in the distant reaches of the solar system — and a new telescope could finally prove its existence. | Credit: Nicholas Forder for Live Science Deep ...

NPR's Madeleine Brand talks with NPR's Ira Flatow, host of Talk of the Nation Science Friday, about this week's announcement of the discovery of a new "planetoid" astronomers have dubbed Sedna. This ...