It seems logical that would NASA select military test pilots to be the first astronauts, right? They were used to risk. They were good with machines. They already explored extreme environments. But these skills were not unique to test pilots. There were also mountaineers, scuba divers, and explorers. They too were considered. So why did NASA choose test pilots?

Matthew Hersch, assistant professor of history at Harvard University and author of Inventing the American Astronaut, talks about this and other aspects of the astronaut program.