MASTER: a Discovery-class mission for the detailed study of large mainbelt asteroids.

Abstract MASTER (Mainbelt Asteroid Exploration/Rendezvous) focuses on the comprehensive global study of important large mainbelt asteroids. A three-instrument, four-investigation payload can be placed into orbit around 4 Vesta within the cost/complexity envelope of the Discovery program using a Delta-ll launch vehicle. The detailed global study of such an object will provide essential-new data on the present state and past evolution of asteroids, including information not obtainable by fast flybys or by rendezvous with mere asteroidal shards such as the tiny Earth-approaching asteroids.