NASA has announced financing for a nuclear-powered rocket that might reduce the time it takes to reach Mars from seven months to 45 days.
The Bimodal Nuclear Thermal Rocket could be utilized to carry both people and freight around the Solar System, avoiding key dangers associated with interplanetary travel such as radiation exposure.
Prof. Ryan Gosse of the University of Florida, the scientist behind the plan, believes it may shorten transit time to Mars to 45 days. If the technology works as expected, it might substantially shorten transit times to Mars and make human expeditions to the red planet infinitely safer.
Is nuclear propulsion the way of the future for humans in space?
The new concept, named “Bimodal NTP/NEP with a Wave Rotor Topping Cycle,” is one of 14 chosen for Phase I development by the NIAC. It obtained a $12,500 grant to investigate and create the necessary technology.
According to Universe Today, NASA has a lengthy history of considering nuclear propulsion for spacecraft. This contains the Nuclear Engine for Rocket Vehicle Application (NERVA) concept, which was tested satisfactorily but eventually defunded around the time the Apollo Era ended in 1973.
In the early 2000s, NASA also evaluated nuclear propulsion idea technologies with Project Prometheus. Meanwhile, Ad Astra, led by retired NASA astronaut Franklin R. Chang Daz, has completed an 88-hour high-power endurance test of their Vasimr VX-200SS plasma rocket at 80 kW in 2021. Ad Astra says that their nuclear rocket technology might eventually transport humans to Mars at speeds of 123,000 miles per hour (197,950 kilometers per hour).
Revolutionary nuclear propulsion concept developed by NASA
NASA’s new NIAC grantee makes use of two essential concepts in nuclear propulsion. Nuclear-Thermal Propulsion (NTP) uses a nuclear reactor to heat liquid hydrogen propellant into plasma, which is then funneled through a nozzle to generate thrust.
Meanwhile, Nuclear-Electric Propulsion (NEP) employs a nuclear reactor to generate electricity for a Hall-Effect thruster (ion engine). This, in turn, forms an electromagnetic field, which ionizes and accelerates an inert gas, resulting in propulsion.
Gosse, the University of Florida’s Hypersonics Program Area Lead, incorporates the benefits of both NTP and NEP in his innovative idea. The engineer suggests a bimodal design based on a NERVA solid-core reactor with a specific impulse (LSP) of 900 seconds. That is twice the performance of currently available chemical rockets.
Gosse further recommends employing a Wave Rotor (WR) to compress the reaction mass utilizing pressure generated by the reactor’s heating of the liquid hydrogen fuel. According to the engineer, this can provide thrust levels equal to NERVA-class NTP concepts, but with a greater Isp of 1400-2000 seconds. When combined with a NEP cycle, this produces considerably more push.
Shorter travel times are critical for astronaut safety
All of this indicates that Gosse’s approach could substantially cut future astronauts’ transit time to Mars. A crewed mission to Mars using existing technologies could take six to nine months to reach the red planet. Reduced travel time to roughly 45 days would allow Mars expeditions to last months rather than years.
This is critical because protracted voyages to Mars would expose astronauts to dangerously high quantities of radiation. Not only that, but the impact of microgravity on humans for such an extended period of time will have detrimental health consequences, implying that there is a strong incentive to lower Mars mission timeframes.