[P-PS07] Formation and evolution of planetary materials in the Solar System

[PPS07-P15] Simulation of Chemical Reactions Induced by Micrometeoroid Impacts on Saturn's Rings: Implications for the Ring Rain Formation Mechanism

*Yoko Ochiai¹, Shigeru Ida¹, Daigo Shoji² (1.Institute of Science Tokyo, 2.ISAS/JAXA)

Keywords:Saturn's ring, Impact vapor plume, Chemical reaction simulation

In this study, we focus on the impact of micrometeoroids on the ice particles that constitute Saturn's rings. When a micrometeoroid collides with a ring particle at high velocity, the high impact energy causes the evaporation and degassing of both the ring particle and the micrometeoroid, leading to the formation of an impact vapor cloud (Hyodo et al., 2024). Within this high-temperature impact vapor cloud, gases originating from the ring particles and micrometeoroids undergo chemical reactions, resulting in new chemical compositions. Therefore, micrometeoroid impacts on ring particles are likely to influence the material evolution of the rings. However, previous studies have not specifically investigated the chemical reactions induced by micrometeoroid impacts on Saturn’s ring particles and the resulting chemical products. In this study, we employ the chemical reaction simulation model developed in our previous work (Ochiai et al., 2024) to simulate the chemical reactions occurring within the vapor cloud generated by micrometeoroid impacts on ring particles. Based on these results, we aim to identify the chemical species produced by impact events in Saturn’s rings and discuss their implications for the rings' evolution, as well as comparisons with Cassini’s observational data.