NASA Completes Early Tests of Mini Nuclear Fission Reactor That Could Power Human Settlements on Mars

NASA has successfully completed tests of a miniature nuclear reactor that could one day power long-term human settlements on the Moon, Mars and beyond.

Kilopower, as the system is known, is a small, lightweight fission reactor. It will be capable of producing up to 10 kilowatts of electrical power—enough to run several households continuously for 10 years. Just four of these reactors would be sufficient to power a Martian outpost, according to NASA.

A reliable and efficient power system will be an essential part of future space missions as humans begin to settle other worlds, enabling outposts to be self-sufficient. The new reactor will provide the power for lighting, water and oxygen, as well as for running experiments and producing fuel. This capability will mean astronauts won't have to take all the resources they need with them, opening up new possibilities for exploration.

The reactor will be especially useful in the challenging environments of places such as the moon and Mars, where generating power using solar panels can be difficult. On Mars, for example, sunlight is limited by seasonal variation and periodic dust storms, which can go on for months. Meanwhile, nighttime on the Moon can last about 14 days.

"We want a power source that can handle extreme environments," Lee Mason, NASA's principal technologist for power and energy storage, said in a statement. "Kilopower opens up the full surface of Mars, including the northern latitudes, where water may reside. On the moon, Kilopower could be deployed to help search for resources in permanently shadowed craters."

Kilopower is still a prototype, but the initial tests—referred to as KRUSTY (Kilopower Reactor Using Stirling Technology)—which took place at the Department of Energy's Nevada National Security Site, were successful, with the device meeting or exceeding expectations on all measures, according to the researchers.

Kilopower consists of a solid, cast-uranium-235 reactor core about the size of a paper-towel roll that generates heat that drives engines, producing electricity.

The purpose of the recent tests, which included a 28-hour mission simulation, was to demonstrate that this setup could generate electricity via nuclear fission—the splitting of atoms to produce energy—and show that the reactor was safe and stable in different environments.

An artist’s rendering of Kilopower, the new fission power system, on the lunar surface. Kilopower will be capable of producing enough power to run several average households continuously for 10 years. NASA

"We put the system through its paces," Marc Gibson, Kilopower lead engineer at NASA's Glenn Research Center, said in a statement.

"We understand the reactor very well, and this test proved that the system works the way we designed it to work. No matter what environment we expose it to, the reactor performs very well."

Now the next step for NASA will be to conduct further tests on the reactor in preparation for flight testing. Looking forward, Kilopower will play an important role in the agency's plans for the Lunar Orbital Platform-Gateway—a proposed space station that will orbit the moon and act as a base for expeditions further into the solar system.

"Safe, efficient and plentiful energy will be the key to future robotic and human exploration," Jim Reuter, NASA's acting associate administrator for the Space Technology Mission Directorate in Washington, said in a statement. "I expect the Kilopower project to be an essential part of lunar and Mars power architectures as they evolve."