This mosaic shows the surfaces of Jupiter’s four Galilean moons images, as seen by NASA’s Galileo spacecraft. NASA/JPL/DLR We know the innermost Galilean, pus-colored Io, is covered in ...

On 12 March 2013, Galileo satellite GSAT0104, alongside its fellow In-Orbit Validation (IOV) satellites, made history by enabling the first position fix by Europe's independent satellite ...

Jupiter may have once been more than twice its current size, with a magnetic field 50 times stronger, say scientists who ...

The twin Galileo satellites are now fully fuelled and mated together atop the upper stage that will haul them most of the way up to their final orbit. The launch is now planned for the evening of ...

On Jan. 7, 1610, Galileo discovered four moons revolving around Jupiter — a discovery that would change his life forever. These four moons are Jupiter’s largest satellites — lo, Europa ...

Jupiter will look bigger and brighter than normal on Monday night as it rises opposite of the sun and reaches its closest point to Earth in decades. It will be so close that the planet's banding ...

A long-exposure image of a Falcon 9 launch of two Galileo satellites April 27. Credit: SpaceX WASHINGTON — A Falcon 9 successfully placed into orbit a pair of Galileo navigation satellites April ...

It was Galileo's misfortune to have observed, through the lenses of his homemade telescope, the mountains on the moon, the varying spots on the sun, and the four major moons of Jupiter as they ...