A new prototype ion engine known as a lithium-fed magnetoplasmadynamic (MPD) thruster has passed a crucial test at NASA. The space agency is hoping to eventually combine this technology with nuclear fission to produce power and thrust for lengthy space flights, such as a crewed mission to Mars.

Kate Kelly

For decades, the thrill of space exploration has ignited the imaginations of engineers, scientists, and innovators alike. The dream of expanding humanity’s reach beyond Earth continues to attract the brightest minds, fueling groundbreaking advancements. As we set our sights on missions that venture farther and last longer in the cosmos, one truth stands out: Nuclear technology is the key to unlocking these bold ambitions. Its impact goes far beyond any single mission, driving a surge of momentum that not only propels space exploration but also energizes the entire nuclear ecosystem—sparking innovation and growth in an era of unprecedented opportunity.

Nuclear rocket propulsion has been investigated for decades, and NASA and the Atomic Energy Commission carried out significant testing in the 1960s as part of the Nuclear Engine for Rocket Vehicle Application program. NERVA chased the potential of the efficiency and energy density of nuclear thermal propulsion to extend our reach to new space frontiers before the program ended in 1973.

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.

The predawn darkness on a cool Florida night was shattered by the ignition of nine Merlin engines on a SpaceX Falcon 9 rocket. The thrust of the engines shook the ground miles away. From a distance, the rocket appeared to slowly rise above the horizon. For the cargo onboard, the launch was anything but gentle, as the ignition of liquid oxygen generated more than 1.5 million pounds of force. After the rocket had been out of sight for several minutes, the booster dramatically returned to Earth with several sonic booms in a captivating show of engineering designed to make space travel less expensive and more sustainable.

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.

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.

The newest addition to Oak Ridge National Laboratory’s materials research facilities is set to host a ribbon-cutting ceremony later this year now that construction is complete and laboratories are being phased into operation. The 100,000-square-foot, multipurpose Translational Research Capability building at ORNL houses a broad spectrum of research ranging from quantum science to energy storage, with several of the largest labs in the building focused on materials challenges for applications including nuclear fission and fusion, like the ORNL’s Corrosion Lab.

Nuclear power in space is back in the news for the second time this week as microreactor start-up Nano Nuclear has released a request for information to identify organizations that may support the company in the development of its Loki micro modular reactor. The company’s goal is eventual deployment of Loki on the lunar surface.

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.”

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.

Zeno Power, a developer of nuclear batteries, is to receive americium-241 recovered from Orano’s La Hague nuclear fuel recycling site in Normandy, France, under a strategic agreement announced by the companies on September 24.

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.

A recent episode of the podcast Space Minds features a discussion about the uses of nuclear power in space with Bhavya Lal, former associate administrator for technology, policy, and strategy at NASA. Lal, who has master’s degrees in nuclear engineering and in technology and policy from the Massachusetts Institute of Technology, is currently a professor at the RAND School of Public Policy and a strategy consultant for Idaho National Laboratory.

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 American Nuclear Society’s Nuclear and Emerging Technologies for Space (NETS 2025) conference will take place May 4–8 in Huntsville, Ala. Registration for the meeting is now open, and the Huntsville Marriott at the Space & Rocket Center is also taking room reservations for attendees.

Westinghouse Electric Company announced last week that NASA and the Department of Energy have awarded the company a contract to continue developing a lunar microreactor concept for the Fission Surface Power (FSP) project.

Jay F. Kunze

We welcome ANS members with long careers in the community to submit their own stories so that the personal history of nuclear power can be captured. For information on submitting your stories, contact nucnews@ans.org.

I was born and raised in Pittsburgh, Pa. In 1959, I received my Ph.D. in experimental nuclear physics utilizing the 400-MeV synchrocyclotron at Carnegie Mellon University, involving measuring the scattering of pi-­mesons from protons (as a liquid hydrogen target). I joined ANS in January 1960.

I later joined General Electric’s Aircraft Nuclear Propulsion project to build a nuclear jet engine at the National Reactor Testing Station at Idaho Falls (now Idaho National Laboratory). In January 1961, the U.S. Army’s experimental nuclear reactor SL-1 blew up, killing three army personnel. At first, the Air Force would not permit General Electric to take part in the cleanup, but after the Aircraft Nuclear Propulsion project was canceled by President Kennedy in March, GE took on the SL-1 disassembly and analysis project. I oversaw the analysis, which took nearly two years.

William A. Anders

William A. Anders, former chairman of the Nuclear Regulatory Commission and a former member of the American Nuclear Society, died on June 7 at 90 years of age.

In a June 18 statement, the NRC offered condolences on his passing.

“Chairman Anders had an illustrious career far beyond taking one of the most widely seen photos from space,” said NRC chair Christopher Hanson. “He was the only person to serve as commissioner on both the Atomic Energy Commission and NRC, and he served as the new agency’s first chairman, providing institutional continuity while unambiguously committing the agency to serve as an unbiased, independent, and open regulator. We are saddened by his death and extend our condolences to his family.”

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.