Diameter4.8 million m
3.8 tenthsEarth diameters
6.9 billionPencil lead widths
4,820.6 km
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Jupiter's most heavily cratered moon/Moons
Callisto is the second largest moon of Jupiter and the third largest moon in the solar system. Its surface is the most heavily cratered of any body in the solar system, a battered landscape that has barely changed in 4 billion years. Unlike its siblings Io and Europa, Callisto is geologically dead, which honestly sounds like a relaxing way to spend eternity.
4,820.6 km
1,882,700 km from Jupiter
About 16.69 days
Average