Using current technology, the space agency says the 300-mile journey to Mars would take about seven months.
Engineers do not yet know how much time could be reduced using nuclear technology. However, Bill Nelson, the Nasa administrator, said “astronauts could journey to and from deep space faster than ever”.
“This is a major capability to prepare for crewed missions to Mars,” Mr Nelson said.
Nasa announced on Tuesday that it would conduct an in-Earth orbit demonstration of its new craft in 2027. This is part of a collaborative project with the Defence Advanced Research Projects Agency (Darpa), the US military’s research and development arm.
Nuclear electric propulsion systems are up to three times as efficient as the chemical rockets currently in operation. The tech uses a core reactor to generate electricity that positively charges gas propellants, such as xenon or krypton, pushing the ions out through a thruster that drives the rocket forward.
The resulting low-thrust acceleration created by this process lasts for longer periods of time, compared with the high-thrust generated by chemical propulsion engines. As well as boosting transit times for crewed spacecraft, nuclear thermal engines are also safer, can carry bigger payloads, and generate more power for instrumentation and communication, Nasa said.
Instead of using highly-enriched uranium, the project will rely on high-assay, low-enriched uranium fuel in an attempt to avoid logistical hurdles, Darpa said.
Nasa’s ultimate goal is to harness nuclear engines to speed up deep space exploration missions, including to Mars. It tested a powerful new rocket last year as part of its Artemis programme designed to return humans to the moon, and serve as a jumping-off point for journeys to the Red Planet.
As part of the new project, Darpa will design an experimental spacecraft and manage the overall programme, known as the Demonstration Rocket for Agile Cislunar Operations, or Draco. Nasa will collaborate on the assembly of the nuclear engine en route to the 2027 demo.
“We will conduct several experiments with the reactor at various power levels while in space, sending results back to operators on Earth, before executing the full-power rocket engine test remotely,” said Dr Tabitha Dodson, Darpa programme manager for Draco. “These tests will inform the approach for future operation of [nuclear thermal rocket] engines in space.”
Nasa is also working with the Department of Energy to develop advanced space nuclear technologies, including three concepts for a nuclear power plant that could be tested on the surface of the moon by 2030. Nasa previously said nuclear fission energy could enable continuous power regardless of location, available sunlight, and other natural environmental conditions. A demonstration of the systems would pave the way for long-duration missions to Mars, it noted.
More than 50 years have passed since Nasa last tested nuclear thermal technology. A major programme was started in the 1960s, under the Nuclear Engine for Rocket Vehicle Application banner. However, this was later scrapped due to a lack of funding before any test flights had occurred.
“Recent aerospace materials and engineering advancements are enabling a new era for space nuclear technology, and this flight demonstration will be a major achievement toward establishing a space transportation capability for an Earth-Moon economy,” Jim Reuter, associate administrator for Nasa’s Space Technology Mission Directorate, said.