This is the only book on the subject, written by one of the foremost experts in the field. Micrometeorites played an essential role in the formation of the atmosphere of the Early Earth, and provided a significant source of activation for organic prebiotic chemistry on mineral surfaces. The book offers a coherent account of this scenario, embedding the more specific results within a broader framework that considers the creation and evolution of the Early Earth. It serves as a modern, compact reference for students and nonspecialist researchers in the fields of planetary atmospheres, biogeophysics and astrobiology.