2025-07-16

The case for a recent collision in the irregular moon system of Saturn

Speaker: Edward Ashton (ASIAA)

Abstract:

The giant planets in the Solar System all have satellites with large inclined eccentric orbits, which are known as irregular moons. Originally captured by their host planet not long after the formation of the Solar System, irregular moons are considered to be one of the most collisionally evolved minor body populations. I will talk about our recent survey of the irregular moon system of Saturn using the Canada-France-Hawaii Telescope. From observations taken between 2019 and 2023 we were able to discover 192 new irregular moons of Saturn, more than quadrupling the known number from 58 to 250. This monumental increase in the number of saturnian irregular has allowed us to see finer detail in their orbital distribution. Our most significant finding is evidence for a recent catastrophic collision within the moon system.