Yeah, it’s Ganymede – the natural satellite of Jupiter.
The planet Jupiter has 63 moons,46 of these are less than 3 km wide and probably used to be asteroids before Jupiter’s gravity pulled them in. The four biggest moons are called the Galilean moons because they were discovered by the Italian astronomer Galileo Galilee. These four are Io, Europa, Ganymede and Callisto.
I’ll be writing a short post about Juno the satellite,that ventured near Jupiter recently.