Seminars

In recent decades, several missions have detected signs of water and other volatile compounds in cold, permanently shadowed craters near the lunar poles. Observations suggest that some of these volatiles could have been delivered by comet impacts. Therefore, understanding the role that comets play becomes key to explaining the origin and distribution of lunar water. During impact, the constituent ices of a comet vaporize; a significant part of this vapor remains gravitationally bound to the Moon, transforming the thin, collisionless lunar exosphere into a collisionally thick, temporary atmosphere. We use the Direct Simulation Monte Carlo (DSMC) method to investigate the physical processes governing volatile transport in the transient atmosphere generated after a comet impact, with a focus on how these processes influence the accumulation of water in polar 'cold traps'.