Ganymede

! colspan="2" style="background: #a0c0ff; text-align:center;" | Orbital characteristics ! colspan="2" style="background: #c0a5a0; text-align:center;" | Physical characteristics ! colspan="2" style="background: #d0a00c; text-align:center;" | Other
 * + Ganymede
 * Orbital period || 11.4403 Terran days 11d 10h 34min 3s 15.7526 Ganymedean days
 * Orbital axis Apojovine Perijovine || 3,210,985 km 3,229,390 km 3,192,570 km
 * Orbital axis Apojovine Perijovine || 3,210,985 km 3,229,390 km 3,192,570 km
 * Orbital axis Apojovine Perijovine || 3,210,985 km 3,229,390 km 3,192,570 km
 * Rotation period || 17.43 hours
 * Mean diameter || 19914 km
 * Surface area Water Land || 1,245,900,000 km² 1,029,300,000 km² (83%) 216,600,000 km² (17%)
 * Temperature Min. Main Max. || 225 K 277 K 310 K
 * Atmospheric pressure (at MSL) || 1145 mbar
 * Surface area Water Land || 1,245,900,000 km² 1,029,300,000 km² (83%) 216,600,000 km² (17%)
 * Temperature Min. Main Max. || 225 K 277 K 310 K
 * Atmospheric pressure (at MSL) || 1145 mbar
 * Atmospheric pressure (at MSL) || 1145 mbar
 * Atmospheric pressure (at MSL) || 1145 mbar
 * Inhabitants Density || 24 (as of 2005) 2.3*10^-8
 * Countries || none recognized (according to UN)
 * }
 * Countries || none recognized (according to UN)
 * }

Ganymede is the most massive planet of Jupiter. It supports life, and humans have settled there successfully.

Physical characteristics
Ganymede has relatively little iron, and most of it is in the core. Mantle and crust are mainly silicates. The planet supports extensive volcanism and plate tectonics.

Most of the surface is ocean, of which parts are frozen. There are few continents.

The deepest place is 18 940 meters deep and the tallest mountain is 9 480 meters high.

History
It is theorized, that around billion years ago unicellular Terran life came to Ganymede, and multicellular organisms around 300 million years ago. Since then, the Ganymedean biosphere developed without animals, before 1949, when the Soviet Union did animal tests in Ganymede by unmanned spacecraft. Before 2005, the animal life of Ganymede consisted only of cats, dogs, bees, flies and monkeys.

Since the conquest of Venus there was a race to Ganymede. The first to land an unmanned spacecraft there was Soviet Union in 1948 and the first to send a man successfully to Ganymede was USA in 2004. The United States astronauts built a settlement there, migrating to Ganymede, sending samples only by an unmanned shuttle and information by radio.

Now there are four settlements on Ganymede: two American, one Chinese and one Japanese.