NASA and the US Department of Energy have signed an agreement covering the whole life of a space nuclear system. It runs from making the fuel through testing, launch integration and operations. NASA Administrator Jared Isaacman and Energy Secretary Chris Wright signed the memorandum of understanding (MOU) on Thursday, Oct. 8, 2026, at the "Science: A Golden Age Summit." The White House Office of Science and Technology Policy hosted the event in Washington.
The document is titled "Accelerating American Leadership in Space Nuclear Power and Propulsion" and takes effect Sunday, Nov. 1. Isaacman put it plainly: "We are entering the 'Nuclear NASA-era,' which represents a major transformation for space exploration."
An MOU sets out how two agencies will work together. It is not a funding bill and it doesn't build anything itself. Its value depends on the specific missions now tied to it, and on whether the nuclear fuel those missions need actually arrives.
What the agreement covers
NASA describes the framework as end-to-end collaboration covering advanced research, fuel production, testing, launch integration and operations. Put simply, the two agencies now have a shared structure for the full process of space nuclear development. NASA calls safety the "central pillar" of the agreement.
The policy backdrop is the December 2025 executive order "Ensuring American Space Superiority." NASA says it directs the agency to develop a launch-ready lunar surface reactor by 2030, a goal NASA says it is pursuing in partnership with the Energy Department. Agencies working to a deadline like that need clear lines of responsibility.
Two reactors, two destinations
NASA's announcement names two projects.
SR-1 Freedom is a nuclear propulsion mission to Mars, which NASA says launches in 2028. The American Nuclear Society's Nuclear Newswire reported that the mission was announced in March and is targeted to launch to Mars in December 2028. That is a little over two years from the signing. NASA says the launch will move nuclear propulsion from laboratory research to operational deep-space use.
Lunar Reactor-1 is the fission surface power system for NASA's Moon Base. NASA says SR-1's milestone paves the way for it, and that it will sustain the Moon Base through darkness and shadow. It fits the executive order's goal of a launch-ready lunar reactor by 2030, though NASA's announcement does not tie the two together explicitly.
The two projects have different jobs. One is going to Mars. The other is meant to power a base on the Moon. NASA says together they form the foundation of a domestic nuclear-space industrial base.
The fuel problem
SR-1 Freedom depends on high-assay low-enriched uranium (HALEU). In July, the Energy Department announced conditional commitments to provide HALEU to NASA and to Radiant Industries. This was the department's third round of allocations, and NASA was a first-time recipient. NASA's share supports the SR-1 Freedom mission to Mars. Radiant's supports deployment of a microreactor at Buckley Space Force Base in Colorado.
The same announcement noted that HALEU is not currently available from domestic suppliers, and that many advanced reactors need the material. Nuclear Newswire reported that the first allocation round came in April 2025 and the second in August 2025. It also reported that Centrus Energy signed a contract to finalize a $900 million DOE task order to expand HALEU production capacity at its Piketon, Ohio, plant.
The allocations came before the new MOU and are separate from it. Still, they show why fuel supply matters to the missions the agreement supports, and the MOU lists fuel production among its areas of work. The Energy Department said it will now begin the contracting process with NASA to allocate the material. A December 2028 launch date does nothing for a reactor that has no fuel.
The existing partnership: radioisotope power and heater units
NASA says the new agreement fortifies existing collaborations on fission and radioisotope power systems. Radioisotope power is a different technology from fission. NASA's announcement mentions two current examples.
The Dragonfly mission to Saturn's moon Titan is scheduled to launch in 2028. It will rely on a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) and 24 Light Weight Radioisotope Heater Units to power and warm the car-sized rotorcraft. NASA and the Energy Department also plan to support the European Space Agency's Rosalind Franklin Mars rover by providing 24 similar heater units to maintain instrument temperatures in the extreme cold of the Martian environment.
These examples show that the two agencies already work together on nuclear flight hardware. The new MOU extends that working relationship across the full range of space nuclear development, including fission.
Why It Matters
NASA says nuclear power will allow spacecraft to go farther, operate longer and carry more capable instruments. It describes fission surface power as the way to sustain a Moon Base through darkness and shadow, and as essential for the demanding energy needs of future Mars missions. For the US, nuclear power has become a central part of plans for a sustained presence on the Moon and for more ambitious missions to Mars.
An agreement that spans fuel production through operations is an attempt to give both agencies one framework for the whole chain, ahead of a hard deadline.
The schedule is tight. SR-1 Freedom is targeted for a December 2028 launch, and the executive order wants a launch-ready lunar reactor by 2030. The HALEU that SR-1 needs does not yet come from domestic suppliers. The MOU won't change that on its own. It does establish a shared framework for the work. Whether the agencies meet their dates will show up in the hardware milestones, which matter more than the agreement itself.
