Launched in Sept. 2007, the Dawn
mission is the first time that a spacecraft will orbit both an
asteroid, Vesta, and a dwarf planet, Ceres. The Dawn spacecraft
will study these two distinct bodies, compare their different
evolutionary paths and characterize the early solar system and
the processes that dominated its' formation.
Dawn's ability to orbit two separate
bodies is made possible by the use of ion
engines, a revolutionary new propulsion system, seen as a blue
beam in my image.
Dawn reached Vesta in August 2011.
Hi-res versions available