http://www.c3.lanl.gov/~cjhamil/SolarSystem/europa.html (Einblicke ins Internet, 10/1995)Jupiter II
Europa [yur-ROH-pah] is a strange looking moon of Jupiter with a large number of intersecting features. It is unlike Callisto and Ganymede with their heavily cratered crusts. Europa has almost a complete absence of craters as well as almost no vertical relief. As one scientist put it, the features "might have been painted on with a felt marker". There is a possibility that Europa may be internally active due to tidal heating at a level one-tenth or less that of Io. Models of Europa's interior show that beneath a thin 5 km (3 miles) crust of water ice, Europa may have oceans as deep as 50 km (30 miles) or more. The visible markings on Europa could be a result of global expansion where the crust could have fractured and then filled with water and froze.
Discovered by ................ Simon Marius & Galileo Galilei Date of discovery ...................................... 1610 Mass (kg) ........................................... 4.8e+22 Mass (Earth = 1) ................................. 8.0321e-03 Equatorial radius (km) ................................ 1,569 Equatorial radius (Earth = 1) .................... 2.4600e-01 Mean density (gm/cm^3) ................................. 3.01 Mean distance from Jupiter (km) ..................... 670,900 Rotational period (days) ........................... 3.551181 Orbital period (days) .............................. 3.551181 Mean orbital velocity (km/sec) ........................ 13.74 Orbital eccentricity .................................. 0.009 Orbital inclination ................................... 0.470° Escape velocity (km/sec) ............................... 2.02 Visual geometric albedo ................................ 0.64 Magnitude (Vo) ......................................... 5.29
Europa
(GIF, 593K)
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 absence
of impact craters. Only three craters larger than 5 km in diameter have
been found.
(Credit: Calvin J. Hamilton, Los Alamos National Laboratory)
Europa From a Distance
(GIF, 39K)
This view of Europa was taken by Voyager 2 and shows a bright,
low-contrast surface with a network of lines which crisscross much
of its surface.
(Credit: Calvin J. Hamilton, Los Alamos National Laboratory)
