Callisto, Jupiter's moon, is likely an ocean world, with evidence suggesting a subsurface ocean beneath its ice shell. Reanalysis of Galileo spacecraft data, ...

Callisto (bottom) together with Jupiter's other Galilean satellites. Image credit: NASA. The possibility that Callisto may have an ocean underneath its icy surface was first proposed in 1998.

Since Callisto also has an intense ionosphere, the team decided to test their methods on 30-year-old measurements taken by NASA's Galileo mission. That mission launched in 1989 and scanned Jupiter ...

Callisto is the eighth closest moon to Jupiter and, of the Galilean satellites, ... Many scientists believe Callisto houses a subsurface ocean located about 100 km beneath the surface.

Callisto, the second-largest moon of Jupiter, is covered in craters and appears, at first glance, geologically inactive. However, magnetic measurements taken by the Galileo probe in the 1990s suggest ...

Callisto, the outermost of the 95 Jovian moons, ... Jupiter’s largest moon, appears to have an internal ocean that potentially contains more water than all of Earth’s oceans combined.

A briny ocean is concealed beneath the icy crust of Jupiter’s fourth largest moon, Europa — with more water than all of Earth’s oceans combined. A subsurface sea on Saturn’s moon Enceladus ...

Callisto might be full of surprises on the inside, too — an underground ocean could lurk here as well, yet another possible abode for alien life out in Jupiter's neighborhood. Bonus boggler ...

The icy Jupiter moons Callisto, Europa and Ganymede all likely host hidden global oceans, but that's not the only reason they stand out.

A subsurface sea on Saturn’s moon Enceladus spews plumes of water vapor into space. And there are tantalizing hints that oceans could exist on Ganymede, Callisto, Titan and other distant moons, too.

A subsurface sea on Saturn’s moon Enceladus spews plumes of water vapor into space. And there are tantalizing hints that oceans could exist on Ganymede, Callisto, Titan and other distant moons, too.