NASA racked up another first over the past weekend as the Dawn spacecraft entered orbit around the asteroid 4-Vesta.
Vesta, discovered in 1807 by Heinrich Olbers, is the brightest asteroid and the second most massive after Ceres. This tiny world lives in the asteroid belt between Mars and Jupiter and is just over 500 km in diamater.
The Dawn mission utilises an ion propulsion system, similar to the one used on ESA's SMART-1 lunar mission. This allows the spacecraft trajectory and velocity to undergo gradual alterations to allow the gravity of Vesta to capture the spacecraft into orbit. After a year in orbit the ion drive will be used again to break out of orbit and head for Ceres.
Scientists hope, through the study of these asteroids by a single set of instruments, to derive details on separate evolutionary paths of these worlds as well as important clues as to conditions in the early solar system.