Europa
Europa is a strange looking moon of Jupiter with a large number of
intersecting features. It is unlike Callisto and Ganymede with
their heavely cratered crusts. Europa has almost a complete absence
of craters as well as almost no vertical relief. This implies
that it has a thin crust of water-ice less than 30 km (18 miles) thick,
perhaps floating on a 50 km deep (30 mile) ocean. The visible markings
could be a result of global expansion where the crust could have
fractured and then filled with water and froze. Europa may be internally
active due to tidal heating.
Title Image
This is one of the highest resolution images of Europa obtained by Voyager
2. It shows the smoothness of most of the terrain and the near absense
of impact craters. Only three craters larger than 5 km in diameter have
been found.
Europa Statistics
Radius: 1563 km
Mass: 4.87 x 10^25 kg
Density: 3.04 gm/cm^3
Distance from Jupiter: 670,900 km
Orbital period: 3.551 days