If there was a contest for the most interesting moon in our solar system, Callisto would be a contender. Jupiter's ...

Dust off your old telescope on a clear night and look up. If you find Jupiter, you’ll likely see four small dots to the side ...

More pocked with craters than any other object in our solar system ... near Callisto that suggested that its ice shell surface—much like that of Europa, another moon of Jupiter—may encase ...

New evidence from an old NASA mission supports the theory that Jupiter's moon Callisto is in fact an ocean world.

New evidence from an old NASA mission supports the theory that Jupiter's moon Callisto is in fact an ocean ... rocks more than 150 miles beneath the surface. Both are key conditions known for ...

A NASA spacecraft has set sail for Jupiter and its moon ... surface. Discovered by Galileo in 1610, Europa is one of the four so-called Galilean moons of Jupiter, along with Ganymede, Io and Callisto.

The probe didn't reach its destination, Jupiter ... time's larger than Earth's moon. A bit less than half of its water-ice crusted surface is dark and pitted by impact craters, NASA says.