Jupiter Ice Moons Explorer (JUICE) is a European spacecraft designed to study the three largest moons of Jupiter: Ganymede, Callisto, and Europa. All three moons appear to have large oceans of liquid water beneath their icy crusts. Europa is of particular because its crust is thinner and it may have more interior heat to warm the ocean, making it both a more comfortable abode for possible microscopic life and an easier world to probe. JUICE is scheduled to enter orbit around Jupiter in July 2031. It will make multiple passes by all three moons, then settle into orbit around Ganymede in December 2034. That will make it the first spacraft to orbit any planetary moon other than Earth's.