Pluto was once dismissed as a frozen leftover at the edge of the solar system, until we finally got a close-up look. What we ...

Pluto, once thought to be a frozen and lifeless world drifting on the edge of our solar system, may be harboring one of its most intriguing secrets: a vast underground ocean. A landmark study ...

Yet Pluto has some geological oddities — in particular, a large number of cracks discovered on the far side — that add support to the existence of a hidden ocean, and even shed light on how it formed.

This composite image of Pluto, right, and Charon, its largest moon, showcases photos captured by NASA’s New Horizons spacecraft in July 2015. Unlike how scientists believe Earth's moon formed billions ...

Some scientists also believe there is a liquid ocean beneath Pluto's ice shell that is estimated to be 249 miles thick. But they thought it formed later in Pluto's history as radioactive elements were ...

CAPE CANAVERAL, Fla. -- Evidence is mounting for an ocean at Pluto, buried beneath its frozen heart. Scientists said Wednesday that Pluto may have rolled over on its axis eons ago, the result of tidal ...

Scientists have been blown away by Pluto’s complex geology in the months following NASA’s historic flyby of the dwarf planet. But it’s not the only interesting world in its system: Charon, Pluto’s ...

A researcher has used advanced models that indicate that the formation of Pluto and Charon may parallel that of the Earth-Moon system. Both systems include a moon that is a large fraction of the size ...