84 Asteroids
![Image of the size comparison of the asteroids are Ceres, Vesta, and Eros.](http://cel.fscj.edu/LUMENS/ast-1002-package/img/figure-149-vestaErosCeres.jpg)
Ceres is the largest asteroid found to date, and was reclassified as a Dwarf Planet in 2006. Ceres appears to be fairly spherical in shape, which is unusual for asteroids in general. Ceres is 950 kilometers or 590 miles in diameter, and makes up a third of the mass of the asteroid belt.
There are a number of interesting asteroid characteristics . Asteroids are most-likely leftover material from the formation of the solar system. Most asteroids are quite irregular in shape, with sizes ranging from around 0.6 mile to 590 miles (Ceres). Asteroids can have satellites. Ida, with its moon Dactyl, was the first discovered pair. Currently more than 150 asteroids are known to have a small companion satellite; some have two moons.
The asteroids are the parent body sources for most meteorite impacts on Earth and on other solar system bodies. Ninety-five percent of the original asteroids are no longer around; most were impactors. An impactor is an object that strikes, or impacts, another object. Asteroid impacts cause catastrophism : the sudden shaping of a planet’s or satellite’s surface due to an asteroid impact.