The mass of the asteroids is found mostly in the larger asteroids, so to estimate the total mass we need to consider only the larger objects. suppose the three largest asteroids—ceres (1000 km in diameter), pallas (500 km in diameter), and vesta (500 km in diameter)—account for half the total mass. assume that each of these three asteroids has a density of 3 g/cm3 and calculate their total mass. multiply your result by 2 to obtain an estimate for the mass of the total asteroid belt. how does this compare with the mass of the oort cloud?