# The Dynamical History of Chariklo and its Rings

## TL;DR

This study investigates Chariklo's orbital history and the stability of its rings by simulating its past 1 billion years, concluding that planetary encounters are unlikely to have significantly affected the rings' formation or stability.

## Contribution

It provides a detailed dynamical history of Chariklo, showing its recent capture into the Centaur population and assessing the impact of planetary encounters on its rings.

## Key findings

- Chariklo's orbit is marginally more stable than other Centaurs.
- Most planetary encounters have minimal impact on the rings.
- Ring formation via tidal disruption during encounters is unlikely.

## Abstract

Chariklo is the only small Solar system body confirmed to have rings. Given the instability of its orbit, the presence of rings is surprising, and their origin remains poorly understood. In this work, we study the dynamical history of the Chariklo system by integrating almost 36,000 Chariklo clones backwards in time for one Gyr under the influence of the Sun and the four giant planets. By recording all close encounters between the clones and planets, we investigate the likelihood that Chariklo's rings could have survived since its capture to the Centaur population. Our results reveal that Chariklo's orbit occupies a region of stable chaos, resulting in its orbit being marginally more stable than those of the other Centaurs. Despite this, we find that it was most likely captured to the Centaur population within the last 20 Myr, and that its orbital evolution has been continually punctuated by regular close encounters with the giant planets. The great majority (> 99%) of those encounters within one Hill radius of the planet have only a small effect on the rings. We conclude that close encounters with giant planets have not had a significant effect on the ring structure. Encounters within the Roche limit of the giant planets are rare, making ring creation through tidal disruption unlikely.