NASA’s Fission Surface Power Project

Key Takeaways

• NASA’s FSP Project targets deploying a 40-100 kW nuclear reactor on the Moon by 2030.
• Three industry teams received $5M Phase 1 contracts in 2022 to develop competing designs.
• China and Russia signed a lunar nuclear cooperation pact in May 2025, intensifying the race.

The Power Problem That Solar Can’t Solve

The Moon’s surface presents a challenge that solar panels simply can’t overcome: lunar nights near the poles last more than 14 Earth days. During those two weeks of darkness, any base relying entirely on sunlight would have to shut down or drain enormous battery reserves just to keep life-support systems running. It’s the kind of operational constraint that makes ambitious long-duration lunar presence essentially unworkable without an alternative energy source.

That’s where NASA’s Fission Surface Power Project enters the picture. Rather than treating nuclear energy as a future option, NASA and its partners are actively working to make it the backbone of sustained human activity on the Moon and, eventually, Mars. The project is designed to provide at least 40 kilowatts of power, enough to continuously run 30 households for ten years. That may not sound like much by terrestrial standards, but on the lunar surface, it’s the difference between a temporary camping expedition and a functional, productive outpost.

The size, weight, and power capability of fission systems make them an effective continuous power supply regardless of location, and a nuclear reactor could be placed in lunar regions where sunlight cannot reach. That matters enormously for any base positioned near the permanently shadowed craters of the south pole, where water ice deposits are believed to exist and where the scientific and strategic value of future operations is highest.

Building on Fifty Years of Nuclear Heritage

The Fission Surface Power Project builds on heritage projects spanning more than 50 years, including SNAP-10A, NASA’s Kilopower project, and recent developments in commercial nuclear power and fuel technology.

The SNAP-10A reactor was launched from the Californian coast on April 3, 1965. It had enough uranium to provide 600 watts of power over a year, but just 43 days into orbit an electrical failure led to the system shutting down. That single flight represented America’s only operational nuclear reactor in space for more than half a century, and the decades that followed saw multiple expensive programs cut before they ever reached the testing stage.

NASA broke that losing streak with Kilopower. The Kilopower project started in October 2015, led by NASA and the Department of Energy’s National Nuclear Security Administration. The fission reactor uses uranium-235 to generate heat that is carried to Stirling converters via passive sodium heat pipes. The concept was elegant in its simplicity, and the cost discipline behind it was almost surprising given the history of bloated space nuclear programs.

The Kilopower nuclear ground testing, nicknamed KRUSTY (Kilopower Reactor Using Stirling TechnologY), was completed at the Nevada Nuclear Security Site on March 21, 2018. The full-scale nuclear demonstration verified the Kilopower reactor neutronics during startup, steady-state, and transient operations in a space-simulated environment. It was the first space reactor test completed for fission power systems in over 50 years.

What made KRUSTY notable wasn’t just that it worked. It was that it worked cheaply. The entire program cost less than $20 million over a three-year period, and the team was able to conduct a full nuclear ground test for roughly 28 hours. The Kilopower reactor was started at approximately 9:00 a.m. on March 20, 2018, and operated for 28 continuous hours.

The testing of KRUSTY represented the first time the United States had conducted ground tests on any space reactor since the SNAP-10A experimental reactor was tested and eventually flown in 1965. With that milestone validated, NASA had a foundation on which to build something much larger.

How a Fission Surface Power System Works

The physics behind a fission reactor are the same whether the device is on Earth or the lunar surface. Fission-based systems work by splitting low-enriched uranium atoms in a reactor to create heat. In fission surface power systems, the heat from the splitting of uranium atoms is converted to electricity.

NASA’s newer Fission Surface Power effort builds on this principle using a closed Brayton cycle power conversion system, which converts heat to electricity. A Brayton cycle system uses differences in heat to spin turbines, generating electrical current in the process. NASA has also awarded contracts to Rolls Royce North American Technologies, Brayton Energy, and General Electric to develop Brayton power converters, with a challenge to make these engines more efficient.

Keeping the system thermally stable in the vacuum of space requires its own engineering solutions. The reactor produces heat continuously, and that heat must be rejected into the surrounding environment. Without an atmosphere to carry away waste heat, lunar fission systems rely on radiators, typically large panel-like structures that radiate heat into space. The design of those radiators is one of the more technically demanding aspects of the entire system.

Idaho National Laboratory has played a central role in the project’s administrative and technical management from the start. The Fission Surface Power initiative is a collaborative effort between the U.S. Department of Energy, NASA, and Idaho National Laboratory to develop and demonstrate a nuclear fission power system capable of supporting long-duration missions on the Moon and Mars. Designed to provide reliable, scalable, and independent power, FSP systems are intended for sustained human and robotic exploration, as well as for powering in-situ resource utilization, science payloads, and habitation systems in environments where solar energy is not viable.

The Phase 1 Contracts and Industry Competition

In June 2022, three teams were awarded twelve-month contracts valued at $5 million each: Lockheed Martin (partnered with BWX Technologies and Creare), Westinghouse (partnered with Aerojet Rocketdyne), and IX (a joint venture of Intuitive Machines and X-energy, partnered with Maxar and Boeing).

Each team brought a distinct technical philosophy to the problem. NASA specified that the reactor should stay under six metric tons and produce 40 kilowatts of electrical power, but deliberately avoided prescribing how teams should reach those goals. The agency’s project manager, Lindsay Kaldon at NASA’s Glenn Research Center in Cleveland, noted that teams were given few requirements on purpose to encourage unconventional thinking.

NASA also set a goal that the reactor should be capable of operating for a decade without human intervention, which is key to its success. That autonomy requirement reflects the reality that lunar surface operations in the 2030s won’t include a maintenance crew standing by to fix a failed component. The reactor has to be robust enough to manage its own fault conditions, regulate its own temperature, and keep delivering power through the unexpected.

Westinghouse Electric Company leveraged its existing eVinci microreactor technology. Working with partner Aerojet Rocketdyne, Westinghouse designed a nuclear-powered reactor capable of generating 40 kilowatts of power. In January 2025, NASA and the DOE selected Westinghouse to continue development of a space microreactor design through a Phase 1A contract, awarded through Idaho National Laboratory. This contract was aimed at optimizing the design and beginning testing of critical technology elements. Westinghouse now describes its updated concept, called AstroVinci, as capable of power ranges between 10 and 100 kilowatts of electrical power, with either Brayton or Stirling power conversion.

Lockheed Martin took a different approach. In January 2025, Lockheed Martin received a Phase 1A extension that added a risk reduction testbed to develop a space nuclear power conversion system, building on the successful Phase 1 design work completed since 2022. Lockheed Martin envisions a modular lunar power grid, starting with a five-to-ten-kilowatt reactor to power a habitat or rover charging station for full lunar day-and-night operations, then scaling to 25-to-50-kilowatt units able to serve multiple habitats, human and scientific rovers, and commercial and industrial activities.

Lockheed Martin’s work on fission surface power is part of a broader space nuclear systems effort that includes a partnership with BWX Technologies on nuclear thermal reactor concepts for NASA and the Department of Energy. BWX Technologies brings decades of experience fabricating nuclear fuel and reactor components, and its involvement across multiple programs reflects just how concentrated the space nuclear supply chain currently is.

IX, the joint venture of Intuitive Machines and X-energy, paired commercial space operations expertise with advanced reactor design knowledge. Intuitive Machines had already demonstrated its lunar delivery capabilities through its NOVA-C landers, while X-energy brought high-temperature gas-cooled reactor experience developed for terrestrial applications.

The August 2025 Directive and the Race to 2030

The pace of the Fission Surface Power Project shifted dramatically in mid-2025. Acting NASA administrator and Secretary of Transportation Sean Duffy issued a directive on August 4, 2025, calling for NASA to move quickly to get a nuclear reactor on the Moon by 2030. The directive established a new Fission Surface Power Program executive position, naming Steven Sinacore, formerly director of aeronautics at NASA’s Glenn Research Center, to the role.

The directive referenced the White House’s Executive Order 14299, signed on May 23, 2025, titled “Deploying Advanced Nuclear Reactor Technologies for National Security.” NASA’s directive emphasized that the FSP project leverages innovation in commercial microreactor technologies and that moving quickly is necessary to support a future lunar economy and high-power energy generation on Mars.

Geopolitics pushed the urgency. Russia and China announced plans in March 2024 to build a nuclear plant on the Moon together. The NASA directive specifically noted that the first country to get a reactor on the Moon could potentially declare a keep-out zone that would significantly inhibit the United States from establishing a planned Artemis presence.

The directive signaled a shift from technology maturation toward deploying an operational system, with NASA’s Space Technology Mission Directorate instructed to immediately cease any new FSP technology maturation efforts that don’t support the anticipated request for proposals and align available fiscal year 2025 funding to support the initial award amount.

NASA issued a draft Announcement for Partnership Proposals in August 2025, followed by a second draft in December 2025 that incorporated industry feedback. The updated draft states NASA intends to offer launch and landing services through the Human Landing System Program and incorporates further refinement in information needed to be compatible with Artemis. A final announcement for partnership proposal release date was anticipated in early 2026.

NASA’s updated Fission Surface Power effort now calls for a system that provides at least 100 kilowatts of electrical power, more than double the original 40-kilowatt target, using a closed Brayton cycle power conversion system.

The project’s stated goals include establishing partnerships with one or more providers to deploy an operational fission surface power system on the lunar surface, energizing the space industrial base to support a future lunar economy, and encouraging dual-use civil and defense operational architectures for fission power systems in coordination with interagency partners.

What the Technology Enables on the Moon and Beyond

Power on a planetary surface isn’t just about keeping the lights on. At 40 kilowatts and above, a fission surface power system opens up categories of activity that are simply not possible otherwise.

High-power fission-based systems on the Moon would enable splitting lunar water into hydrogen that can be used for propellant, and oxygen for astronauts to breathe, potentially creating a water-based economy on the Moon where what is needed to fuel space travel can be extracted and utilized on the lunar surface. In-situ resource utilization, the process of manufacturing useful materials from what’s already on a planetary surface, is widely seen as the key to making space exploration economically sustainable rather than purely an exercise in government expenditure. A reactor that runs for a decade without human intervention changes the calculus entirely.

The 40-kilowatt system is expected to power lunar habitats, rovers, backup grids, and science experiments, and after a one-year demonstration on the Moon, the reactor is designed to complete nine additional operational years.

Mars is the longer-range target. NASA studies have shown that a 40-kilowatt reactor would be sufficient to support a crew of between four and six astronauts on Mars. During those missions, the reactor would provide power for the machinery necessary to separate and cryogenically store oxygen from the Martian atmosphere for ascent vehicle propellants. Once humans arrive, the reactor would power their life-support systems and other requirements. Mars receives roughly 40 percent of the sunlight that reaches Earth, which makes solar power far less effective there than even on the Moon, and the planet’s frequent dust storms can reduce solar irradiance further still.

A nuclear fission reactor is far more powerful than the radioisotope thermoelectric generators on many of today’s deep space missions and could support energy-intensive spacecraft systems. L3Harris Technologies is working on a nuclear generator solution to power lunar and Mars surface operations, drawing on its legacy of providing radioisotope thermoelectric generators for deep space missions.

The China-Russia Challenge

There’s no avoiding the competitive framing here. China and Russia signed a memorandum of understanding in May 2025 on jointly building a nuclear power station on the Moon, intended to serve the International Lunar Research Station, jointly led by both nations, with construction scheduled between 2033 and 2035.

Wu Weiren, chief designer of China’s lunar exploration program, stated that Russia has a competitive advantage in space-based nuclear technology and leads the world in that area, ahead of the United States. That’s a pointed assessment from someone directly involved in building a competing program.

The ILRS is still in its early developmental stages, with mission objectives focused on resource exploration, environmental monitoring, and communications testing. It does not yet involve long-term human presence or require continuous power for large-scale scientific equipment. It’s worth keeping perspective on the timeline: an announcement of intent is not a deployed reactor, and both Russia and China face serious engineering and financial obstacles in achieving a lunar nuclear system by 2035. Still, the direction of travel is clear.

After Politico reported on the NASA directive in August 2025, Duffy confirmed the plans during a live-streamed press conference, saying the United States is in a race with China to the Moon, and that to have a base on the Moon, energy is needed, framing fission technology as an integral part of that effort.

Whether that race framing is analytically accurate or strategically convenient is ly hard to say. The technical challenges facing any country attempting to deploy an operational nuclear reactor on the lunar surface by 2030 or 2035 are formidable, and neither NASA nor its competitors have a perfect record of delivering complex space hardware on schedule. The honest uncertainty isn’t whether nuclear power will eventually reach the Moon. It’s which program will get there first, and whether the current urgency in Washington will translate into sustained funding discipline over the next several years.

Institutional Structure and Management

NASA’s Fission Surface Power Project is managed by NASA’s Glenn Research Center in Cleveland, Ohio. Technology development and demonstration are funded by the Space Technology Mission Directorate’s Technology Demonstration Missions program, located at Marshall Space Flight Center in Huntsville, Alabama.

A 2016 memorandum of understanding between NASA and the DOE serves as the basis of this inter-agency work. An October 2020 NASA-DOE memorandum of understanding expanded on it, establishing working groups that focus on space nuclear power and propulsion.

Glenn Research Center’s involvement makes historical sense. Cleveland has been a center of NASA’s power systems work for decades, and the expertise in power conversion, heat rejection, and electrical systems needed for a fission surface power program is concentrated there. The project manager, Lindsay Kaldon, is based at Glenn, and the center has been the hub for coordinating the complex multi-contractor technical development across Phase 1 and the evolving Phase 2 structure.

The Fission Surface Power project seeks to bring about new capabilities supporting a lunar sustainable presence and crewed Mars exploration while providing near-term opportunities for fabrication, testing, and flight of a space nuclear power system.

The Department of Energy’s national laboratory network has been equally central. Idaho National Laboratory took a lead administrative role in managing the industry contracts and coordinating with the nuclear industry, drawing on Battelle Energy Alliance as its management and operating contractor. Los Alamos National Laboratory contributed reactor physics expertise dating back to the KRUSTY experiment, and the Nevada National Security Site provided the test infrastructure for nuclear demonstrations.

Fuel Strategy and Safety

The choice of uranium enrichment level for a space reactor has significant policy and security implications. Fission surface power reactor designs will focus on using low-enriched uranium fuels, and a DOE reactor study completed in March 2020 identified low-enriched uranium reactor solutions roughly the same weight as the high-enriched system.

That shift to low-enriched uranium is not purely technical. High-enriched uranium, which was used in the KRUSTY test, creates greater proliferation concerns during ground handling, transport, and international cooperation. By demonstrating that low-enriched uranium can achieve comparable performance at similar mass, the March 2020 study opened the door to a reactor design that’s easier to certify, transport, and integrate with international partners without triggering nuclear security protocols that might otherwise complicate a space launch.

Safety during launch is another area of careful design attention. The mechanics of the system make it safe to handle and launch because the nuclear reactor is in an inert, inactive configuration during launch and is designed not to turn on and start the fission process until the spacecraft or surface system is in a safe, appropriate operational state far from Earth. A reactor that can’t go critical during launch removes the most significant public safety concern associated with nuclear payloads on conventional rockets.

What Comes Next

After Phase 2, the target date for delivering a reactor to the launch pad is in the early 2030s. On the Moon, the reactor will complete a one-year demonstration followed by nine operational years. If the demonstration succeeds, the reactor design may be adapted for potential use on Mars.

NASA intends to establish one or more partnerships with U.S. industry to deploy an operational lunar fission surface power system, with the dual goals of advancing fission surface power technologies to support a future lunar economy and enabling power generation capabilities on Mars.

Lockheed Martin envisions a modular approach in which a small initial reactor can grow into a lunar power grid, with units of varying sizes serving different mission phases as human and commercial activity on the Moon expands. That scalability argument may be one of the most commercially compelling aspects of the entire enterprise. A single government-funded demonstration reactor is a scientific achievement. A system architecture that can be expanded to meet commercial demand is a business.

The Westinghouse AstroVinci concept, drawing from the company’s terrestrial eVinci sodium-cooled microreactor lineage, reflects a similar philosophy of building lunar power technology on a commercial foundation rather than treating it as a one-off government program. The overlap between terrestrial microreactor development and space power systems is not coincidental. Companies like Westinghouse are betting that the engineering work needed for lunar deployment will also accelerate the commercial viability of small modular reactors for remote power applications on Earth.

Summary

NASA’s Fission Surface Power Project represents the most serious American effort to deploy nuclear energy on another planetary body since the SNAP-10A mission of 1965. Built on the technical foundation of the KRUSTY experiment and driven forward by a combination of scientific necessity and geopolitical urgency, the project has moved through a competitive Phase 1 contracting process involving Lockheed Martin, Westinghouse, and the Intuitive Machines and X-energy joint venture IX, and is now heading toward deployment-focused industry partnerships targeting the early 2030s.

The August 2025 directive from NASA’s acting administrator accelerated the timeline and raised the power target to 100 kilowatts, reflecting both the scale of what a sustainable lunar base will actually need and the pressure created by China and Russia’s announced plans for a joint lunar nuclear reactor by 2035. Whether the 2030 target for an American reactor on the Moon proves realistic will depend on factors that go beyond engineering: sustained budget appropriations, regulatory approvals for nuclear launches, and the ability of industry partners to execute on unprecedented space hardware without the delays that have plagued so many large-scale space programs.

What’s not in question is that nuclear fission, long set aside in favor of solar power for most space applications, has returned to the center of human exploration planning. The Moon’s 14-day nights, Mars’s dust-dimmed skies, and the energy demands of in-situ resource utilization have collectively made the case that solar and batteries alone won’t sustain a human presence beyond low Earth orbit. The Fission Surface Power Project is NASA’s answer to that constraint, and the investment of time, money, and institutional attention behind it suggests the agency intends to see it through.

Appendix: Top 10 Questions Answered in This Article

What is NASA’s Fission Surface Power Project?

NASA’s Fission Surface Power Project is a collaborative program between NASA, the U.S. Department of Energy, and Idaho National Laboratory to develop and deploy a small nuclear fission reactor on the lunar surface. The reactor is designed to provide at least 40 to 100 kilowatts of continuous electrical power for lunar habitats, rovers, and other systems. It is managed by NASA’s Glenn Research Center in Cleveland, Ohio.

Why does the Moon need nuclear power instead of solar panels?

Lunar nights near the poles last more than 14 Earth days, during which solar panels generate no power at all. A fission reactor produces continuous electricity regardless of sunlight, time of day, or location, including permanently shadowed craters near the south pole where water ice may be found. This makes nuclear power far more reliable for sustained human operations than solar arrays alone.

What was the KRUSTY experiment and why did it matter?

KRUSTY, the Kilopower Reactor Using Stirling TechnologY, was a full-scale nuclear ground test conducted at the Nevada Nuclear Security Site from November 2017 to March 2018. It was the first space reactor test completed in the United States in over 50 years and validated the performance of the Kilopower reactor design under normal and abnormal operating conditions. The entire program cost less than $20 million, making it one of the most cost-effective nuclear demonstration programs in NASA history.

Which companies received Phase 1 contracts for the Fission Surface Power Project?

In June 2022, NASA and the Department of Energy awarded three $5 million Phase 1 contracts through Idaho National Laboratory. The winners were Lockheed Martin (partnered with BWX Technologies and Creare), Westinghouse Electric Company (partnered with Aerojet Rocketdyne), and IX (a joint venture of Intuitive Machines and X-energy, partnered with Maxar and Boeing). Each team developed independent reactor design concepts for a lunar demonstration system.

What is the target power output and operating lifetime for the lunar reactor?

The original specification called for 40 kilowatts of electrical power, enough to continuously power roughly 30 households for ten years. Following the August 2025 directive, the power target was raised to at least 100 kilowatts. The reactor is designed to operate for one year as a demonstration, followed by nine years of operational service, for a total of approximately ten years without requiring human maintenance.

What happened in August 2025 that changed the pace of the program?

Acting NASA administrator Sean Duffy issued a directive on August 4, 2025, calling for an accelerated deployment timeline targeting a nuclear reactor on the Moon by 2030. The directive created a new Fission Surface Power Program executive position, named Steven Sinacore to fill it, and instructed NASA’s Space Technology Mission Directorate to redirect available funding toward an industry partnership solicitation rather than continued technology maturation.

What is China and Russia doing in the space nuclear power field?

Russia’s space agency Roscosmos announced in March 2024 its intention to build a nuclear reactor on the Moon with China between 2033 and 2035, intended to power their joint International Lunar Research Station. China and Russia signed a formal memorandum of understanding on the project in May 2025. The ILRS is still in early development, but the joint commitment has accelerated urgency in the U.S. program.

What fuel does the Fission Surface Power reactor use?

Fission surface power reactor designs focus on using low-enriched uranium fuel, following a 2020 Department of Energy study that identified low-enriched solutions at roughly the same mass as high-enriched alternatives. This choice reduces proliferation concerns during ground handling, transportation, and international coordination. The reactor is also designed to remain in an inert, inactive configuration during launch and not begin fission operations until it is safely deployed on the lunar surface.

How does a fission surface power system convert heat to electricity?

The reactor generates heat by splitting uranium atoms in a controlled chain reaction. That heat is transferred via systems such as sodium heat pipes and then converted to electricity by Stirling engines or closed Brayton cycle turbines, depending on the specific design. The updated NASA specification for the next phase of the program calls for a closed Brayton cycle power conversion system.

What does a lunar nuclear reactor make possible that wasn’t possible before?

Beyond basic power supply, a 40-to-100-kilowatt fission reactor enables in-situ resource utilization at meaningful scale, including splitting lunar water into hydrogen for rocket propellant and oxygen for life support. It provides enough power to operate multiple habitats, rover charging stations, and scientific instruments simultaneously. On Mars, the same reactor class could support a crew of four to six astronauts with power for life support, atmospheric oxygen extraction for propellant, and science operations.