Researchers estimate that Europa's hidden ocean contains more than twice the water found in all of Earth's oceans combined.

"This helps future missions interpret what they find and better understand where to look for signs of habitability." ...

Europa might not be the best place to look for alien life in the solar system after all. A new study modeling what the floor of the Jupiter moon's hidden ocean is like concluded that tectonic activity ...

Add Yahoo as a preferred source to see more of our stories on Google. Callisto, Jupiter's second-largest moon, may have a rocky surface with an ocean beneath the surface. If there was a contest for ...

More pocked with craters than any other object in our solar system, Jupiter's outermost and second-biggest Galilean moon, Callisto, appears geologically unremarkable. In the 1990s, however, NASA's ...

The giant planet Jupiter has nearly 100 known moons, yet none have captured the interest and imagination of astronomers and space scientists quite like Europa, an ice-shrouded world that is thought to ...

New evidence from an old NASA mission supports the theory that Jupiter's moon Callisto is in fact an ocean world. Credit: NASA / JPL / DLR A moon of Jupiter about the size of Mercury likely has a ...

COMPOSITE PIC: Photo of Jupiter moon 'Europa' taken by Galileo Jupiter probe space-craft. (Photo by Time Life Pictures/JPL/NASA/Time Life Pictures/Getty Images) COMPOSITE PIC: Photo of Jupiter moon ...

Among the solar system’s hundreds of known moons, few are as enticing as the handful that scientists believe have a global ocean lurking below their crusty surface. But two of these hidden oceans may ...

Ganymede, Jupiter's largest moon, possesses planet-like dimensions and a hidden ocean. This moon is larger than Mercury and ...

If there was a contest for the most interesting moon in our solar system, Callisto would be a contender. Jupiter’s second-largest moon has more impact craters on its surface than any other planetary ...