Cratering and age of Saturn?s small satellites

ROSSIGNOLI, N. L.; DI SISTO, R. P.; ZANARDI, M.; DUGARO, A

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2019 vol. 627 p. 1 - 12

0004-6361

Context. The small ( 135 km mean radius) saturnian satellites are closely related to the rings and together they constitute a complexdynamical system where formation and destruction mechanisms compete against each other. The Cassini-Huygens mission providedhigh resolution images of these satellites? surfaces and therefore allowed for the calculation of observational crater counts.Aims. We model the cratering process by Centaur objects on the small saturnian satellites, and compare our results with the observationalcrater counts obtained from the Voyager and Cassini missions.Methods. Using a theoretical model previously developed we calculate the crater production on these satellites considering two slopesof the size-frequency distribution (SFD) for the smaller objects of the Centaur population and compare our results with the availableobservations. In addition, we consider the case of catastrophic collisions between these satellites and Centaur objects and calculatethe age of formation of those satellites that suer one or more disruptions.Results. In general we find that the observed crater distributions are best modeled by the crater size distribution corresponding tothe s2 = 3:5 index of the SFD of impactors with diameters smaller than 60 km. However, for crater diameters D