Erik Asphaug, Author of When the Earth Had Two Moons

Ted Prezelski talks with planetary scientist Erik Asphaug, who wrote When the Earth Had Two Moons: Cannibal Planets, Icy Giants, Dirty Comets, Dreadful Orbits and the Origins of the Night Sky. The book is an exploration of both the history of our solar system and the history of planetary science. The discussion touches on science education as well as the place of astronomy in popular imagination.