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
Himalia (moon) Himalia (moon) Himalia is the largest irregular satellite of Jupiter. It is the sixth largest Jovian satellite overall in size, and only the four Galilean moons of Jupiter have greater mass. It was discovered by Charles Dillon Perrine at the Lick Observatory on 3 December 1904 and is named after the nymph Himalia, who bore three sons of Zeus (the Greek equivalent of Jupiter). It is one of the largest planetary moons in the Solar System not imaged in detail, and the largest not including the moons of Neptune and several trans-Neptunian objects, particularly Dysnomia, the moon of . Himalia