253 Mathilde is a main belt asteroid found by Johann Palisa in 1885. It has a fairly elliptical orbit that takes more than four years to circle the Sun. This asteroid has an unusually slow rate of rotation, taking 17.4 days to complete a 360° revolution about its axis. It is a primitive C-type asteroid, which means the surface has lots of carbon; giving it a dark surface that reflects only 4% of the light that falls on it.