Radioisotope power systems have enabled more than 90 percent of all non-human operational time on the lunar surface. (Source: Zeno Power)
The American Nuclear Society recently hosted a new webinar in its ongoing Educator Training series titled, “Powering the Lunar Frontier: Nuclear Energy for the Artemis Era.” This webinar featured a presentation from Harsh Desai, chief commercialization officer at Zeno Power and chair of the Nuclear Energy Institute’s Space Nuclear Taskforce.
The Harmonia RPS for Artemis Tipping Point's electrical heat source subassembly engineering unit prior to thermal vacuum chamber testing. (Photo: Zeno Power)
Earlier today, Zeno Power announced the completion of the final design review for an americium-241–fueled radioisotope power system (RPS) developed for Harmonia RPS, a NASA Artemis Tipping Point project.
The Harmonia RPS project will now begin the build and fabrication phase. Zeno plans to complete a terrestrial demonstration of an electrically heated system in early 2027 and is aiming for flight qualification for lunar missions beginning in 2028.
Artist’s concept of Phase 3 of NASA’s Moon Base. (Image: NASA)
A White House Office of Science and Technology Policy (OSTP) memorandum released on Tuesday guides NASA, the Department of Energy, and the Department of Defense on their roles in deploying near-term space nuclear power.
This follows a series of NASA announcements last month—driven by the executive order “Ensuring American Space Superiority,” issued by Trump in December—including an ambitious timeline for establishing a moon base, which would rely on fission surface power (FSP) to survive the long lunar night at the moon’s south pole, and plans for a nuclear electric propulsion (NEP) rocket to be launched in 2028.
A still from a NASA video illustrating Space Reactor-1 Freedom. (Image: NASA)
Yesterday NASA announced a series of initiatives, including plans to launch a nuclear electric propulsion spacecraft to Mars in December 2028 and a three-phase plan to establish a lunar base incorporating nuclear-driven heat and power.
Secretary of Energy Chris Wright (left) and NASA Administrator Jared Isaacman (right) meet at DOE headquarters in Washington, D.C., on January 8. (Photo: NASA/John Kraus)
NASA and the Department of Energy have announced a “renewed commitment” to their mutual goal of supporting research and development for a nuclear fission reactor on the lunar surface to provide power for future missions. The agencies have signed a memorandum of understanding that “solidifies this collaboration and advances President Trump’s vision of American space superiority.”
Concept art of a fission surface power system on the surface of the moon. (Image: Lockheed Martin)
The “space race” is once again making headlines, with technology worthy of the 21st century. Like the Cold War–era competition, this race too is about showcasing power—but this time it's nuclear power.
A new article in Power Technology examines the competing efforts of the United States, Russia, and China as they strive to be the first to put a nuclear reactor on the moon to power a lunar base, detailing the technical challenges and international rivalries.
A still image from a NASA video illustrating power needs on the lunar surface. (Image: NASA)
After the Trump administration’s new push to get a nuclear reactor on the moon by 2030 was first reported by Politico last month, media played up the shock value for people new to the concept. Few focused on the technical details of the new plan for lunar fission surface power (FSP), which halts and replaces a program that began under the first Trump administration with an early hope of getting a reactor on the moon by the end of 2026. Now, the focus is on streamlining NASA’s internal processes to support commercial space companies that can build a reactor with more than twice the power and mass and have it ready for launch by 2030.
In this artist’s concept, a notional spacecraft with a high-power plasma thruster is powered by kilowatt-level radiovoltaics. (Image: DARPA/Alan Clarke)
You could call it a power contest. Teams picked for a new research program from the Defense Advanced Research Projects Agency (DARPA) will compete to design radiovoltaic cells that can outperform others in measured power density and endure high-flux radiation from a U.S. Army Research Lab linear accelerator. The top teams will strive to make it through a second downselect based on the performance of cells sequestered in time capsules and subjected to even more punishing high-flux radiation. Concepts that make it to the bonus period have a chance to be built into radioisotope-fueled power systems uniquely suited to high-radiation regions of space or dark, remote places on Earth.
Artist’s impression of NASA’s Dragonfly approaching a landing site on Saturn’s moon Titan. Essentially a flying chemistry lab, along with cameras and other science instrumentation, Dragonfly will travel between dozens of landing sites on Titan’s surface to investigate the chemical origins of life. (Image: NASA/Johns Hopkins APL/Steve Gribben)
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
The H9 Hall thruster, developed at UMich’s Plasmadynamics and Electric Propulsion Laboratory. (Image: William Hurley/University of Michigan)
Seeking spacecraft that can “maneuver without regret,” the U.S. Space Force is investing $35 million in a national research team led by the University of Michigan to develop a spacecraft with an onboard microreactor to produce electricity, with some of that electricity used for propulsion. But this spacecraft would not be solely dependent on nuclear electric propulsion—it would also feature a conventional chemical rocket to increase thrust when needed.
Understanding how several different metals—such as the contents of PNNL’s space-bound cube—react to radiation in space will help scientists understand the potential impact of radiation on space travelers. (Photo: Eddie Pablo/PNNL)
When a SpaceX rocket lifted off from Kennedy Space Center on September 10 (see video here), sending a crewed commercial mission into low Earth orbit, an experiment designed by Pacific Northwest National Laboratory was onboard. Several high-purity metal samples will orbit Earth and absorb cosmic radiation for five days—including that from the Van Allen radiation belt—to help the lab answer questions about the radiation environment for manned space missions, according to a news release from PNNL.
Concept art of ESA’s Rosalind Franklin rover. (Image: ESA/ATG medialab)
Europe’s first Mars rover—named Rosalind Franklin—was months away from a planned September launch when the European Space Agency (ESA) convened a meeting a few weeks after Russia’s February 2022 invasion of Ukraine. The ESA Council unanimously agreed on “the present impossibility” of working with Roscosmos as its launch partner and later decided to reboot its ExoMars mission with a new lander, new partners, and a new launch date.
Fabricated Z1 heat source in transfer port. (Photo: Zeno Power)
Zeno Power, a developer of commercial radioisotope power systems (RPSs), announced on October 26 that it has completed the design, fabrication, and testing of its Z1 strontium-90 heat source. According to Zeno, they have tested the first commercially developed radioisotope heat source and reached a key milestone for Zeno to begin delivering RPSs to customers in 2025.
Concept art of a nuclear thermal propulsion system. (Image: USNC)
Ultra Safe Nuclear (USNC) announced on October 17 that it had been awarded a contract by NASA to develop and mature space nuclear thermal propulsion (NTP) systems to advance the nation’s cislunar capabilities. Under the contract, USNC says it will manufacture and test proprietary fuel and simultaneously collaborate with its commercial partner, Blue Origin, to mature the design of an NTP engine optimized for near-term civil science and cislunar missions.