Add Yahoo as a preferred source to see more of our stories on Google. A huge, unusually dense planet more than twice the size of Earth is puzzling scientists because it has very little atmosphere, ...

Over the past century, astronomers have speculated about the existence of a mysterious 9th planet lurking in the outer reaches of our solar system. Although we’ve never directly observed the elusive ...

A star 1,300 light-years away appears to have just consumed one world and is gearing up for seconds. By Becky Ferreira A star located about 1,300 light-years from Earth shows signs of having devoured ...

As far-fetched as it may seem, quirks of orbital mechanics could allow hundreds of planets to be packed around a star ...