William K. Hartmann

William K. Hartmann is a prominent American planetary scientist and author known for his work on the geology and history of planets, especially Mars and the Moon. He played a significant role in lunar studies and contributed to the understanding of planetary formation. Hartmann also co-authored the influential book "The History of Earth," which explores the geological and biological evolution of our planet. His research has helped to shape our understanding of the solar system and its bodies, making him an important figure in planetary science.