Universe Today
The rings around this asteroid were first noticed in 2013 when the asteroid underwent a stellar occultation. This revealed a system of two rings, with a radius of 391 and 405 km and widths of about 7 km 3 km, respectively. The absorption features of the rings showed that they were partially composed of water ice. In this respect, they were much like the rings of Jupiter, Saturn, Uranus and the other gas giants, which are composed largely of water ice and dust.
This was followed by findings made in 2015 that indicated that 2006 Chiron - another major Centaur - could have a ring of its own. This led to further speculation that there might be many minor planets in our Solar System that have a system of rings. Naturally, this was a bit perplexing to astronomers, since rings are fragile structures that were thought to be exclusive to the gas giants of our System.
As Professor Othon Winter, the lead researcher of the Sao Paulo team, told Universe Today via email:
"At first it was a surprise to find a Centaur with rings, since the Centaurs have chaotic orbits wandering between the giant planets and having frequent close encounters with them. However, we have shown that in most of the cases the ring system can survive all the close encounters with the giant planets. Therefore, Centaurs with rings might be much more common than we thought before."
"At first it was a surprise to find a Centaur with rings, since the Centaurs have chaotic orbits wandering between the giant planets and having frequent close encounters with them. However, we have shown that in most of the cases the ring system can survive all the close encounters with the giant planets. Therefore, Centaurs with rings might be much more common than we thought before."
"The study was made in two steps. First we considered a set of more than 700 clones of Chariklo. The clones had initial trajectories that were slightly different from Chariklo for statistical purposes (since we are dealing with chaotic trajectories) and computationally simulated their orbital evolution forward in time (to see their future) and also backward in time (to see their past). During these simulations we archived the information of all the close encounters (many thousands) they had with each of the giant planets."
"In the second step, we performed simulations of each one of the close encounters found in the first step, but now including a disk of particles around Chariklo (representing the ring particles). Then, at the end of each simulation we analyzed what happened to the particles. Which ones were removed from Chariklo (escaping its gravitational field)? Which ones were strongly disturbed (still orbiting around Chariklo)? Which ones did not suffer any significant effect?"
