is developing plans for an ambitious mission to orbit three
planet-sized moons of Jupiter -- Callisto, Ganymede and
Europa -- which may harbor vast oceans beneath their icy
surfaces. The mission, called the Jupiter Icy Moons Orbiter,
would orbit each of these moons for extensive investigations
of their makeup, their history and their potential for sustaining
Galileo spacecraft found evidence that Jupiter's large icy
moons appear to have three ingredients considered essential
for life: water, energy and the necessary chemical contents.
The evidence from Galileo suggests melted water on Europa
has been in contact with the surface in geologically recent
times and may still lie relatively close to the surface.
Observations of Callisto and Ganymede would provide comparisons
key to understanding the evolution of all three moons. The
Jupiter Icy Moons Orbiter would support one of NASA's main
goals: to explore the universe and search for life.
orbiter would also raise NASA's capability for space exploration
to a revolutionary new level by pioneering the use of electric
propulsion powered by a nuclear fission reactor. This technology
not only makes it possible to consider a realistic mission
for orbiting three of the moons of Jupiter, one after the
other, it would also open the rest of the outer solar system
to detailed exploration in later missions.
Mission Fact Sheet