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Project Orion Nuclear Pulse Spacecraft Program

Project Orion was not an anti-gravity rumor or a fictional starship sketch. It was a real Cold War study into nuclear pulse propulsion: a spacecraft accelerated by repeated nuclear explosions behind a massive pusher plate and shock absorber system. The strongest public record ties Orion to Stanislaw Ulam's nuclear-pulse concept, Ted Taylor and Freeman Dyson's General Atomics work, ARPA sponsorship, Air Force interest, NASA-era mission studies, and the political wall created by the 1963 Limited Test Ban Treaty. The program never flew and never became a deployed spacecraft, but it remains one of the most extreme serious propulsion studies in the declassified space archive.