The US space agency NASA says it will develop a rocket engine using nuclear thermal propulsion technology for a future manned mission to Mars.
NASA announced the joint project with DARPA, the Defense Advanced Research Projects Agency, on Tuesday. DARPA is a research and development institution of the US Department of Defense.
The new rocket engine will be propelled by heat generated by nuclear fission inside a small reactor.
NASA says nuclear thermal rockets can be three or more times more efficient than conventional chemical propulsion.
Faster travel times will reduce the risk for astronauts. Shorter trips also require less food and other supplies.
NASA is planning an in-space demonstration of the new rocket engine as early as 2027.
Safety remains a key challenge in using nuclear power in space.