The OSIRIS-REx spacecraft recently reached Bennu, a 492-meterwide rocky asteroid that is not believed to have a differentiatedinterior. Clearly suggest a reason why Bennu did not differentiatecompared to rocky planets, which seem to have distinct cores,mantles, and crusts. Then, explain what principle may have causedEarth's Moon to be rocky in composition, while all of Saturn'smoons are primarily icy in composition.
