There are only five bodies in our solar system that are known to bear rings. The most obvious is the planet Saturn; to a lesser extent, rings of gas and dust also encircle Jupiter, Uranus, and Neptune. The fifth member of this haloed group is Chariklo, one of a class of minor planets called centaurs: small, rocky bodies that possess qualities of both asteroids and comets.
Scientists only recently detected Chariklo's ring system—a surprising finding, as it had been thought that centaurs are relatively dormant. Now scientists at MIT and elsewhere have detected a possible ring system around a second centaur, Chiron.