Massachusetts Institute of Technology | via EurekAlert | 2015 Mar 16
Researchers detect features around Chiron that may signal rings, jets, or a shell of dust
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.
- [i]Chariklo is the largest Centaur, an icy world in the realm between asteroids and comets. In 2013, it was discovered to have not one, but two, rings. Chariklo is about 250 km or so in diameter. Its inner ring is at 391 kilometers from the center of Chariklo and is 7 kilometers wide. Its outer ring is at 405 kilometers and is 3 kilometers wide. The gap between the rings is 8 kilometers wide. [b](© Don Davis)[/b][/i]
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.
In November 2011, the group observed a stellar occultation in which Chiron passed in front of a bright star, briefly blocking its light. The researchers analyzed the star's light emissions, and the momentary shadow created by Chiron, and identified optical features that suggest the centaur may possess a circulating disk of debris. The team believes the features may signify a ring system, a circular shell of gas and dust, or symmetric jets of material shooting out from the centaur's surface.
"It's interesting, because Chiron is a centaur -- part of that middle section of the solar system, between Jupiter and Pluto, where we originally weren't thinking things would be active, but it's turning out things are quite active," says Amanda Bosh ...
29 November 2011 stellar occultation by 2060 Chiron: Symmetric jet-like features - Jessica D. Ruprecht et al
- Icarus 252 271 (15 May 2015) DOI: 10.1016/j.icarus.2015.01.015
A second ringed centaur? Centaurs with rings could be common
Planetary Society | 2015 Jan 27
Possible ring material around centaur (2060) Chiron - J.L. Ortiz et al
- arXiv.org > astro-ph > arXiv:1501.05911 > 23 Jan 2015