Ceres is the largest Solar System asteroid. It has a mean diameter of 950 km and resides in the asteroid belt, between the orbits of Mars and Jupiter. Ceres is much larger than the other asteroid belt objects, which are typically < 100 km in diameter. Due to its large size, Ceres is also classified as a dwarf planet.

An HST image of the largest asteroid, Ceres.
Credit: NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI)