1st period March 24, 2015
Distance from planet: 671,100km
Rotation period [Earth days]:3.5
Composition: silicate rock, and a thin layer of ice
Europa is very smooth ,few features have been seen.
Europa has liquid water in it and meets the three minimum requirements for life to exist.
Europa causes large tides on Jupiter
Distance from planet:[km] 1,868,768
Rotation period: 16.689 earth days
Atmosphere [principle gases]: Carbon dioxide
Composition: 40% ice 60% rock
Callisto was named after a nymph that was turned into a bear by Hera the goddess, the wife of Zeus. After Hera turned Callisto into a bear, Zeus put Callisto in the sky, and turned her into the constellation Ursa Major.
Many of the largest craters are surrounded by rings.The largest of these craters is called Valhalla.
Gipul Catena is a long series of craters lined up in a straight line.
Unlike Ganymede, with it's complex terrains, there is little tectonic activity on Callisto.