A ring system detected around the Centaur (10199) Chariklo

BRAGA-RIVAS, F.; SICARDY, B.; ORTIZ, J. L.; ...; GIL-HUTTON, R. Y 61 CO-AUTORES

NATURE

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2014 vol. 508 p. 72 - 75

0028-0836

Hitherto, rings have been found exclusively around the four giantplanets in the Solar System1. Rings are natural laboratories in whichto study dynamical processes analogous to those that take place dur-ing the formation of planetary systems and galaxies. Their presencealso tells us about the origin and evolution of the body they encircle.Here we report observations of a multichord stellar occultation thatrevealed the presence of a ring system around (10199) Chariklo,which is a Centaur?that is, one of a class of small objects orbitingprimarily between Jupiter and Neptune?with an equivalent radiusof 124 + 9 kilometres (ref. 2). There are two dense rings, with respec-tive widths of about 7 and 3 kilometres, optical depths of 0.4 and0.06, and orbital radii of 391 and 405 kilometres. The present ori-entation of the ring is consistent with an edge-on geometry in 2008,which provides a simple explanation for the dimming3 of the Cha-riklo system between 1997 and 2008, and for the gradual disappear-ance of ice and other absorption features in its spectrum over thesame period4,5. This implies that the rings are partly composed ofwater ice. They may be the remnants of a debris disk, possibly con-fined by embedded, kilometre-sized satellites.