The seismic signature of lunar ice.

Identifying water ice deposits on the Moon is critical for enabling long-term scientific investigations and supporting future lunar infrastructure. Although multiple lines of evidence suggest that substantial quantities of poleward water exist within the lunar near-surface, the precise location, abundance, and distribution of these ice resources remain largely unconstrained. The presence of ice in the regolith alters geophysical properties that can be quantitatively characterized using geophysical techniques analogous to those employed in terrestrial subsurface resource exploration. In this study, we integrate experimental measurements of icy regolith simulants obtained through synchrotron x-ray microtomography with advanced rock physics modeling and a thermal model of the lunar near-surface. This multi-pronged approach enables us to construct realistic seismic models for theoretical ice deposits at the lunar south pole. Our methodology allows us to link variations in seismic properties to the presence and distribution of ice, providing a framework for using seismic methods to infer both the location and the abundance of subsurface ice deposits. Our results underscore that seismic exploration techniques are a robust tool for characterizing lunar water resources. The insights gained from these models not only enhance our understanding of the physical state of the lunar regolith but also pave the way for optimizing geophysical survey strategies in upcoming lunar missions.