NASA will partner with the US Army's Research and Development Agency, DARPA, to develop nuclear-powered rockets that can transport astronauts to Mars.
NASA stated that it could allow spacecraft to travel faster, reduce transit time, and have other benefits such as increased payloads on missions.
On Tuesday, Administrator Bill Nelson noted that the US space agency could "develop and demonstrate advanced nuclear thermal propulsion technology as soon as 2027."
"With the help of this new technology, astronauts could journey to and from deep space faster than ever, a major capability to prepare for crewed missions to Mars," Nelson said.
According to engineers, a trip to Mars from Earth using this technology could take about four months instead of about nine months using a conventional chemical-powered engine.
NASA abandoned nuclear heat propulsion technology about 50 years ago due to a lack of funding and a shift in priorities toward developing chemical rocket engines for the Apollo program.
There were also safety concerns.
DARPA now says it uses highly assayed low-enriched uranium instead of highly enriched uranium.
"As an added safety precaution, DARPA plans to engineer the system so that the DRACO engine's fission reaction will turn on only once it reaches space," it said in a statement.
NASA successfully tested the new-age Artemis spacecraft last year, the first step toward returning humans to the Moon and then Mars.
However, the thermonuclear rocket engine will be tested first on DARPA's experimental spacecraft. The US Space Force plans to provide launch operation for the experimental mission.
Meanwhile, NASA would continue its Artemis program, with a crewed mission to fly around the moon sometime this year before landing "the first woman and next man on the moon by 2024."