Josh Aaron Cassada is an American physicist, test pilot, and NASA astronaut. Prior to his selection to join NASA in 2013, Cassada served as a test pilot in the US Navy, and has over 3,500 hours in more than 40 aircraft, and 23 combat missions. In August 2018, Cassada was selected for CTS-1, the first operational mission of the Boeing CST-100 Starliner, but subsequently reassigned to SpaceX Crew-5.