<P> Lunar soil is the fine fraction of the regolith found on the surface of the Moon . Its properties can differ significantly from those of terrestrial soil . The physical properties of lunar soil are primarily the result of mechanical disintegration of basaltic and anorthositic rock , caused by continuous meteoric impact and bombardment by interstellar charged atomic particles over years . The process is largely one of mechanical weathering in which the particles are ground to finer and finer size over time . This situation contrasts fundamentally to terrestrial soil formation , mediated by the presence of molecular oxygen ( O ) , humidity , atmospheric wind , and a robust array of contributing biological processes . Some have argued that the term `` soil '' is not correct in reference to the Moon because on the Earth , soil is defined as having organic content , whereas the Moon has none . However , standard usage among lunar scientists is to ignore that distinction . </P>
why does the moon have a layer of powdery soil on its surface
caused by continuous meteoric impact and bombardment by interstellar charged atomic particles over years