Regolith (Greek: "blanket rock") is a layer of loose, heterogeneous material covering solid rock. It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, some asteroids, and other planets. The term was first defined by George P. Merrill in 1897 who stated, "In places this covering is made up of material originating through rock-weathering or plant growth in situ. In other instances it's of fragmental and more or less decomposed matter drifted by wind,… (More on Regolith)