10199 Chariklo is a ringed asteroid and centaur in the outer Solar System. It is the largest known centaur, with a diameter of about 250 km (160 mi). It orbits the Sun between Saturn and Uranus with an orbital period of 62.5 years. It was discovered on 15 February 1997 by the University of Arizona's Spacewatch project at Kitt Peak National Observatory. Chariklo has a dark, reddish surface composed of water ice, silicate minerals, amorphous carbon, and various complex organic compounds.