Planetary scientists continue to debate what Sedna’s presence says about the history of our solar system. Now, S. Alan Stern of the Southwest Research Institute in Boulder, Colorado, says large bodies ...

When the distant planetoid Sedna was discovered on the outer edges of our solar system, it posed a puzzle to scientists. Sedna appeared to be spinning very slowly compared to most solar system objects ...

Sedna is drifting into a part of its path where human technology can finally contemplate catching up, and that window will not reopen for roughly the span of recorded civilization. Its 11,400 year ...

Sedna was initially observed to possess an unusually slow rotation period of 20 days, leading astronomers to hypothesize the presence of an unseen companion moon responsible for this sluggish rotation ...

A team of researchers has outlined how a new "direct fusion drive" propulsion system could allow us to reach Sedna this century. Given the dwarf planet's wide orbit, it could be our best chance for ...

Sedna, the Solar System's farthest known object, does not have a moon, puzzled astronomers have revealed. Its slow spin was thought to be due to the gravity of a small, companion body. Researchers ...

Astronomers studying 35 NASA Hubble Space Telescope (HST) images of the solar system's farthest known object, unofficially named Sedna, are surprised the object does not appear to have a companion ...