Solar System evolution from compositional mapping of the asteroid belt

Unexpected diversity in the asteroids in the main asteroid belt holds clues to mixing via planetary migration in the early Solar System. Plenty of action in the main asteroid belt The main asteroid belt, once regarded as a sort of dumping ground for the spent remnants of planet formation, has emerged in recent years as a region of dynamic activity that provides a window on the processes that are still shaping our Solar System and the many extrasolar planetary systems across the Universe. Francesca DeMeo and Benoit Carry review recent advances in the discovery and characterization of asteroids. More than half a million asteroids have been discovered and mapped since the 1980s, revealing remarkable diversity in size, composition and orbit. New evidence has demonstrated substantial mixing through planetary migration and the subsequent dynamical processes. Next year NASA's Dawn space probe is due to rendezvous with Ceres, the largest body in asteroid belt and one recently proven to contain water, so many new developments in this field can be expected. Advances in the discovery and characterization of asteroids over the past decade have revealed an unanticipated underlying structure that points to a dramatic early history of the inner Solar System. The asteroids in the main asteroid belt have been discovered to be more compositionally diverse with size and distance from the Sun than had previously been known. This implies substantial mixing through processes such as planetary migration and the subsequent dynamical processes.