The astronauts of the Kepler II, the first manned mission to the asteroid belt, launched from Earth. Even with a new ion engine that halved space travel time, the mission was supposed to take over half a decade, with a four year round trip. The aim of the mission was to establish a base on the asteroid Vesta 4. This base, in theory, would allow for quicker observation of the outer planets and lower mission durations for probes.