Asteroid
Although their location in the asteroid belt excludes them from planet status, the three largest objects, Ceres, Vesta, and Pallas, are intact protoplanets that share many characteristics common to planets, and are atypical compared to the majority of "potato"-shaped asteroids. The fourth largest asteroid, Hygiea, has an undifferentiated interior, like the majority of asteroids. Between them, the four largest asteroids constitute half the mass of the asteroid belt.
2 Pallas
Both Vesta and Pallas have assumed the title of second-largest asteroid from time to time. At in diameter, Pallas is slightly smaller than Vesta (). The mass of Pallas is only 84% that of Vesta, 22% that of Ceres and about 0.3% that of the Moon.