Effect of Regolith–Ice Stratigraphy and Laser Weathering on Ultraviolet–Visible–Near-infrared Detection of Lunar Water Ice

Investigating volatiles is critical for understanding their delivery to the Moon and for their potential as a resource for sustained lunar exploration. Water ice and potentially other volatiles are known to exist in and proximal to permanently shadowed regions (PSRs). However, their form, distribution, abundance, and regolith stratigraphy remain poorly understood. NASA’s Artemis program, along with international missions, seeks to address these knowledge gaps with observations at different scales (e.g., from orbit and surface operations). In this study, we replicated three distinct ice stratigraphies in a cryogenic, vacuum environment analogous to PSRs. We then measured the ultraviolet–visible–near-infrared (UV–vis–NIR) reflectance spectra of the volatile-rich samples before and after subjecting them to laser weathering. Our findings reveal that near-surface stratigraphy and weathering phenomena significantly affect the detectability of ice. Hence, spectra from our analog regolith–ice stratigraphies provide a foundational reference for interpreting data from future missions that aim to detect water using UV–vis–NIR reflectance techniques.