US team develops nuclear propulsion concept to shorten Mars trip

Ohio State University engineers have developed a novel nuclear thermal propulsion concept called the centrifugal nuclear thermal rocket (CNTR), which uses liquid uranium to directly heat rocket propellant. This design aims to double the efficiency of conventional nuclear thermal rockets, achieving a specific impulse of around 1800 seconds—significantly higher than the 450 seconds typical of chemical engines and 900 seconds of older nuclear models. The enhanced efficiency could reduce round-trip Mars missions to approximately 420 days, with the potential for one-way trips in just six months, thereby addressing the critical issue of prolonged astronaut exposure to space hazards. Beyond Mars, the CNTR’s powerful thrust and flexibility in propellant choice—including ammonia, methane, propane, or hydrazine—could enable faster missions to outer planets and Kuiper Belt objects, supporting both crewed and robotic exploration. The ability to utilize in-space resources could also facilitate sustainable space presence. However, the technology faces significant engineering challenges such as ensuring stable engine operation, minimizing uranium fuel loss