Saturn, Jupiter’s outer neighbour, currently has 83 known satellites. The four larger moons mentioned above, also known as the 'Galilean moons', account for 99.997 percent of the total mass of Jupiter ...

On the fiery Io, the innermost and third-largest of Jupiter’s four Galilean moons, Juno's observations have provided more insights about its incessant volcanic activity. It's a world home to ...

And thus, Io, Europa and Ganymede became known as the Galilean moons of Jupiter. Learn more about NASA’s current mission to Europa here. Multimedia editor Rob Landers wrote and verified this ...