Which natural phenomenon contributes to the formation of lunar regolith?

The formation of lunar regolith, which is the layer of loose, fragmented material covering solid bedrock on the Moon's surface, is primarily the result of impact cratering. When meteoroids, asteroids, or comets collide with the lunar surface, the violent impacts generate shock waves that fracture and displace the Moon's surface material. This process not only breaks apart existing rock but also grinds it into fine dust and small particles, contributing to the regolith.

Unlike Earth, the Moon lacks a substantial atmosphere and water, which means other weathering processes, such as erosion by wind or seismic activities like earthquakes, do not play a significant role in altering the lunar surface. Volcanic activity on the Moon occurred in its early history but is not a current contributor to the formation of the regolith. As a result, the ongoing impacts from space debris remain the primary force shaping and creating the regolith on the lunar surface.