Impact-Driven Cr-Fe-O Vaporization and Deposition on the Moon

Abstract

Hypervelocity impacts from micrometeorites or asteroids are a dominant long-term geological process that modifies the mineralogical and elemental components of surface regolith on the Moon and other airless planetary bodies. However, the pathways by which impacts drive elemental redistribution on the Moon remain poorly understood. Here, we report the discovery of thousands of chromite (FeCr₂O₄) nanoparticles deposited on a space-weathered olivine fragment from Chang'e−5 lunar regolith. These chromite nanoparticles display morphological and textural characteristics consistent with vapor-phase condensation rather than magmatic crystallization. We therefore propose that the deposited chromite nanoparticles formed via localized vaporization of Cr, Fe, and O from lunar regolith during hypervelocity impacts, followed by rapid condensation and deposition. This study provides direct mineralogical evidence for impact-driven Cr-Fe-O vaporization and deposition, offering new insights into the elemental cycling and regolith evolution on the Moon and other airless bodies.