Long posited as a potential human outpost in science fiction, Jupiter’s icy moon of Callisto largely remains a mystery to real life planetary scientists. As one of the least studied of Jupiter and ...

A recent analysis finds up to 1,000 times more molecular oxygen than can be explained by prevailing theories about where it comes from. Jupiter’s four largest moons are some of the solar system’s most ...

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 ...

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 ...

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 ...

In a landmark observation by a team of international researchers, NASA's Juno spacecraft has, for the first time, clearly detected the auroras of Jupiter's moon Callisto. This discovery completes the ...

The Galilean moon Callisto disappears behind Jupiter in an occultation early this morning. The catch is that the event is only visible from the western half of the U.S., but observers farther east can ...

Astronomers have spotted gaseous carbon dioxide across the atmosphere of Jupiter’s second-largest moon, Callisto, hinting that it might have a much more complex carbon cycle than we thought. On Earth, ...

Add Yahoo as a preferred source to see more of our stories on Google. Like Earth, Jupiter experiences brilliant auroras around its poles — but something funky happens with Jupiter's Galilean moons ...

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 ...