Regolith (Greek: Ρηγόλιθος)'s a layer of loose, heterogeneous material covering solid rock. The term's a combination of two Greek words: Rhegos (Greek: Ρήγος), which means blanket, and Lithos (Greek: Λίθος), which means rock. It includes dust, soil, broken rock, and other related materials and's present on Earth, the Moon, some asteroids, and other planets. The term was first defined by George P. Merri… (More on Regolith)