NERVA - Nuclear Rockets! #NERVA #NuclearPropulsion #NASA #MarsMission #RocketScience #history #space

Added: 2026-05-17

[00:00:00]In the Nevada desert during the Cold War, engineers built a rocket engine that didn't burn fuel the normal way. It used a nuclear reactor. The program was called NURVA, short for nuclear engine for rocket vehicle application.

[00:00:17]Beginning in 1955 under the Atomic Energy Commission and NASA, the goal was simple. Build a rocket powerful and efficient enough to push humans to Mars.

[00:00:32]Chemical rockets work by combustion.

[00:00:34]Nerva, it worked by splitting atoms.

[00:00:38]Inside the engine, a compact uranium reactor heated liquid hydrogen to temperatures approaching 4500° F, about 2,480°.

[00:00:51]The superheated hydrogen expanded violently and blasted through the nozzle to produce thrust. No explosion, no nuclear detonation, just heat from controlled vision. The advantage, it was efficiency. Saturn 5's chemical upper stages achieved roughly 450 seconds of specific impulse. Nurva tested near 850 seconds, nearly double the fuel efficiency of the best chemical rockets of the era. That was a big deal in space. Every pound saved on fuel meant more cargo, more range, and shorter travel times. Some mission studies suggested nuclear thermal rockets could reduce a Mars trip from roughly 8 or 9 months to closer to 3 or 4 months depending on trajectory and mission design, lowering astronaut exposure to cosmic radiation and prolonged weightlessness. And unlike paper concepts, Nerva it actually worked. At Jackass Flats, Nevada, engineers successfully test fired multiple reactors all the way through the 1960s.

[00:02:02]Some engines operated for nearly two hours cumulatively and restarted multiple times, proving that they could survive real mission conditions. And then politics changed. After Apollo, budgets collapsed. Mars missions were postponed indefinitely. In 1973, despite successful tests, NERVA was cancelled before ever flying in space. Today, nuclear thermal propulsion, it has returned to serious discussion. NASA and DARPA are again studying reactor power spacecraft for future deep space missions. Because chemical rockets, they're good at leaving Earth, but nuclear rockets, well, that may be what finally carry humans all the way to another planet.

[00:02:51]These are interesting things with JC.