The fraction of hydrated C-complex asteroids in the asteroid belt from SDSS data

► Sample of over 3800 C-complex asteroid observations from SDSS. ► Roughly 1/3 are in class associated with CM meteorites and hydrated minerals. ► Fraction higher by 5-10% in mid asteroid belt compared to inner and outer zones. ► Fraction stable with size over 35-120 km range. ► Adding data from other surveys shows fraction is much higher for sizes >120 km.