Exploration of Jupiter its first Large mission, replacing its contribution to EJSM, the "Jupiter Ganymede Orbiter" (JGO). The partnership for the Europa Jupiter System Mission has since ended, but NASA will continue to contribute the European mission with hardware and an instrument. The "Europa Clipper" is a mission proposed to NASA to focus on studying Jupiter's moon Europa. In March 2013, funds were authorized for "pre-formulation and/or formulation activities for a mission that meets the science goals outlined for the Jupiter Europa mission in the most recent planetary decadal survey". The proposed mission would be set to launch in the early 2020s and
Moons of Jupiter eccentricity) and composition; it is believed that these are at least partially collisional families that were created when larger (but still small) parent bodies were shattered by impacts from asteroids captured by Jupiter's gravitational field. These families bear the names of their largest members. The identification of satellite families is tentative, but the following are typically listed: The moons of Jupiter are listed below by orbital period. Moons massive enough for their surfaces to have collapsed into a spheroid are highlighted in bold. These are the four Galilean moons, which are comparable in size to the Moon. The other moons