Regolith in Motion: Dynamic Surface Evolution After Lunar Impacts

Abstract Multi‐temporal observations captured by the Lunar Reconnaissance Orbiter Camera provide valuable insights into contemporary surface changes. These images reveal that minor impact events (resulting in 1,000 crater diameters) by increasing the meter‐to‐submeter photometric roughness. Here, we document the first observed decadal‐scale changes in the photometric response consistent with the rapid reconstruction of a porous surface structure within the first decade after an impact. We propose that these changes are driven by the redistribution of fine particles through a combination of micrometeoroid impacts, charged‐particle interactions, and the solar radiation‐induced photoelectric effect. This reworking of the upper regolith results in the overturning of particle facets directly exposed at the surface, affecting the time at which individual facets are exposed to space weathering processes. This continual process and exposure of fresh particle surfaces suggest a dynamic equilibrium between impact‐driven disruption and regolith recovery.