Ganymede (Jupiter III) is a seventh moon of Jupiter. With a diameter of 5,268 km. it is 8% larger than Mercury (but has only 45% of its mass) and 2% larger than Titan. Ganymede is probably composed of approximately equal amounts of silicate rock and water ice. A saltwater ocean is believed to exist nearly 200 km beneath its surface, sandwiched between layers of ice.

The possibility that it might be habitable has drawn recent attention from scientists.


Science FictionEdit

  • Robert A. Heinlein. 1953. Farmer in the Sky.
  • The Oracle of Ganymede by Frank Cavallo. Raygun Revival. Volume 2, Issue 15. April 19, 2012.