A vast, flat sheet of dark matter may solve the long-standing mystery of why our neighboring galaxy Andromeda is speeding toward us while our other neighbors are moving away from…

Where will the failed Soviet spacecraft Kosmos 482 land when it crashes back to Earth in the coming week? Most major cities are in the potential crash zone — but…

Researchers have detected a gamma-ray burst outside of the Milky Way that's unlike any previously observed. There's no satisfying explanation for the mysterious cosmic explosion, but it may be linked…