Archive: https://archive.today/F1c0K From the post: "Nuclear thermal rockets do indeed have impressive performance. Their specific impulse is up to three times greater than chemical rockets, they produce comparable amounts of thrust and they could be designed to accept a variety of propellants, from CO2 to ammonia. They can reduce travel times in space, push around much larger payloads and get refuelled with whatever fluid is available at their destination. "