The race to the moon dominated space flight during the decade of the 1960s. Yet, during the late 1950s and early 1960s, the US government sponsored a project that could possibly have sent 150 people on expeditions to Mars or Saturn. The codename of the project was Orion, and it centered upon the effort to develop a 40,000-ton, fast, manoeuvrable, nuclear-powered space vehicle for long-range voyages in space. Strictly classified, Project Orion ultimately failed. In this book, George Dyson, son of physicist Freeman Dyson, one of the original project team, tells his father's story.