Water at the Moon’s poles is a key resource for future missions like Artemis III. Some of this water may come from a surprising source—molten rock formed during asteroid impacts, known as impact melt. When a large object hits the Moon, it generates extreme heat, melting part of the surface. This molten material can release small amounts of water as it cools and spreads.

In this study, we modeled how water released from 24 impact craters could travel and freeze in cold, permanently shadowed regions (PSRs) near the lunar south pole—areas that never see sunlight and are cold enough to trap water as ice. We used a physics-based model to simulate how this water could move and settle over long distances.

Our early results show that impact melt may contribute measurable amounts of water to these cold traps—up to hundreds of microns thick in some areas. While this is a small contribution overall, it could be an important piece of the puzzle in understanding where lunar water comes from. In the future, we plan to expand our study to include more craters and refine our estimates.