Exploration of Jupiter reach Europa after a 6.5 year cruise. The spacecraft would fly by the moon 32 times to minimize radiation damage. Because of the possibility of subsurface liquid oceans on Jupiter's moons Europa, Ganymede and Callisto, there has been great interest in studying the icy moons in detail. Funding difficulties have delayed progress. The "Europa Orbiter" was a planned NASA mission to Europa, which was canceled in 2002. Its main objectives included determining the presence or absence of a subsurface ocean and identifying candidate sites for future lander missions. NASA's "JIMO" ("Jupiter Icy Moons Orbiter"), which was canceled in 2005, and
Amalthea (moon) a landing easy. From the surface of Amalthea, Jupiter would look enormous: 46 degrees across, it would appear roughly 92 times larger than the full moon. Because Amalthea is in synchronous rotation, Jupiter would not appear to move, and would not be visible from one side of Amalthea. The Sun would disappear behind Jupiter's bulk for an hour and a half each revolution, and Amalthea's short rotation period gives it just under six hours of daylight. Though Jupiter would appear 900 times brighter than the full moon, its light would be spread over an area some 8500 times greater and