how big is ganymede compared to earth's moon
Ganymede (moon) Ganymede is the largest and most massive moon in the Solar System. Its diameter of 5,268Â km is 0.41 times that of Earth, 2% larger than that of Saturn's Titan (the second-largest moon), 1.08 times Mercury's, 1.09 times Callisto's, 1.45 times Io's and 1.51 times the Moon's. Its mass is 10% greater than Titan's, 38% greater than Callisto's, 66% greater than Io's and 2.02 times that of the Moon.[38]