NASA charts nuclear-powered Mars missions from 2028, but timeline and safety remain contested
NASA plans to launch its first nuclear-powered interplanetary spacecraft to Mars by December 2028 and deploy a small reactor on the Moon by 2030, though technical feasibility and regulatory frameworks remain unsettled.
NASA is moving forward with plans to send nuclear-powered spacecraft to Mars, with the Space Reactor-1 Freedom mission scheduled for launch by December 2028. If realised, it would mark the first time the agency uses a fission reactor to both power an interplanetary spacecraft and drive its propulsion system, according to reporting from The Conversation.
The mission is part of a broader pivot toward nuclear power for deep-space exploration. The White House has also established a National Initiative for American Space Nuclear Power, signalling federal commitment to the technology. Separately, NASA plans to deploy a small nuclear reactor on the Moon by 2030 as part of its Artemis program, though such a system would bear little resemblance to terrestrial nuclear power plants.
Why nuclear in space now?
The case for nuclear is grounded in physics and logistics. The Moon experiences a day-night cycle lasting about 29.5 Earth days, with darkness persisting for roughly a fortnight. Establishing a permanent human presence will require power sources that operate reliably through that extended night. Solar power alone is unlikely to suffice.
For Mars missions, nuclear propulsion offers a tangible advantage: it could reduce travel times and—critically—lower astronauts' exposure to cosmic radiation during the journey. Nuclear-generated electricity would power advanced thrusters capable of reaching Mars faster than conventional chemical rockets.
Nuclear power systems in space come in two main forms. Radioisotope power systems generate electricity from the heat released by the natural decay of plutonium-238. Fission reactors, by contrast, split atoms to release heat that can be converted to electricity, much as they do on Earth.
A proven heritage, but questions ahead
The technology is not untested. Apollo missions deployed radioisotope thermoelectric generators on the Moon decades ago. Today, the Mars rovers Curiosity and Perseverance, as well as the ageing Voyager spacecraft in interstellar space, all rely on radioisotope systems for power. That track record lends credibility to NASA's ambitions.
Yet obstacles remain. Technical feasibility is uncertain—the reporting emphasizes that "timelines are only part of the story." Nuclear power in space also demands responsible governance. The race to the Moon and beyond is accelerating, and questions linger about whether the benefits will extend beyond spacefaring nations and private actors.
Nuclear power in space also has to be governed responsibly.
The broader context matters. Interest in space-based nuclear power is no longer confined to NASA. A growing list of national and regional space agencies, private companies, and research institutions are pursuing their own nuclear initiatives in space. The geopolitical and technical landscape is shifting.
The Conversation's reporting does not resolve disputes over feasibility timelines or the readiness of regulatory frameworks to govern such missions responsibly—signalling that while NASA's plan is formal and publicly backed, the path to December 2028 and beyond remains contested among experts.