Recent results on Chariklo's rings

Recent results on Chariklo's rings
2 septembre 2014
On June 3, 2013, a multi-chord stellar occultation revealed the unexpected presence
of two dense rings around 10199 Chariklo, the largest Centaur object with a radius of
124  9 km. [A Centaur is a small body beyond Jupiter, on an orbit which crosses
that of one or more of the outer planets]. The two rings have respective orbital
radii, widths and normal optical depths of a1 = 391 km, W1 = 7 km, 1 = 0:4 and
a2 = 405 km, W2 = 3 km, 2 = 0:06. They are separated by a clear gap about 9
km wide (Braga-Ribas et al - Nature, Volume 508, Issue 7494, pp. 72-75 (2014)).
The presence of those rings has been conrmed during several other stellar occul-
tations observed over the past few months (February and April 2014).
This is the rst ring system ever observed around a small solid body. The existence of
such a system raises several questions as to the origin and evolution of rings around
such an object. The small number of minor planets surveyed thus far suggests that
Chariklo's rings may not be an isolated case.
We will present additional results on azimuthal variations in the rings, estimate the
masses of their putative shepherding satellites, and suggest possible models for the
rings' formation.