Particles co-orbital to Janus and Epimetheus: a firefly planetary ring
Abstract
The Cassini spacecraft found a new and unique ring that shares the trajectory of Janus and Epimetheus, co-orbital satellites of Saturn. Performing image analysis, we found this to be a continuous ring. Its width is between 30% and 50% larger than previously announced. We also verified that the ring behaves like a firefly. It can only be seen from time to time, when Cassini, the ring and the Sun are arranged in a particular geometric configuration, in very high phase angles. Otherwise, it remains "in the dark", not visible to Cassini's cameras. Through numerical simulations, we found a very short lifetime for the ring particles, less than a couple of decades. Consequently, the ring needs to be constantly replenished. Using a model of particles production due to micrometeorites impacts on the surfaces of Janus and Epimetheus, we reproduce the ring, explaining its existence and the "firefly" behavior.
Keywords
Cite
@article{arxiv.1801.01909,
title = {Particles co-orbital to Janus and Epimetheus: a firefly planetary ring},
author = {Othon C. Winter and Alexandre P. S. Souza and Rafael Sfair and Silvia M. Giuliatti Winter and Daniela C. Mourão and Dietmar W. Foryta},
journal= {arXiv preprint arXiv:1801.01909},
year = {2018}
}