This is an image of Ganymede.
Ganymede was first discovered
by Galileo in 1610, making it one of the Galilean Satellites
. Of the 60 moons it is the 7th closest to Jupiter, with a standoff distance of 670,900 km. It is the largest moon in the solar system, much larger than the Earth's moon, with a diameter that is about the distance across the United States, of 5262 km (3270 miles).
Ganymede is named after Jupiter's favorite cup bearer, from Greek/Roman mythology. Ganymede is one of the Icy Satellites, meaning that it is mostly made of ice. Its main characteristic is the grooved terrain on its cratered surface.
The Galileo spacecraft made an amazing discovery-- this moon, which is larger than the planet Mercury, generates its own magnetosphere, one that is bigger than Mercury’s magnetosphere. Ganymede also has a very thin atmosphere.
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