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Robin George Andrews begins with a proposal that sounds reckless at first: put a nuclear reactor on the moon. Yet the basic logic is hard to escape. Any permanent lunar base will need steady electricity and heat through a night that lasts roughly 14 Earth days. Solar panels and batteries alone are unlikely to support habitats, scientific instruments and machinery for extracting water from lunar soil. If NASA wants the moon to become an outpost for research, mining and eventual travel to Mars, nuclear fission may be the only practical long-term power source.

The idea is no longer only speculative. After NASA’s acting administrator Sean Duffy announced a plan for a lunar reactor by 2030, the agency’s current administrator, Jared Isaacman, reaffirmed the goal. China and Russia have also discussed supplying their planned lunar research station with nuclear power by 2035. Andrews’s article is not an argument against a reactor. It is an argument for taking the engineering and political risks seriously before a race to be first compresses the work that safety requires.

The article distinguishes a reactor from the nuclear power sources already used in space. Since the 1960s, spacecraft have often relied on radioisotope thermoelectric generators, or RTGs. These devices act like durable nuclear batteries: radioactive material steadily releases heat that can be converted into modest amounts of electricity. RTGs are suitable for probes and rovers, but not for a settlement that must maintain life support, regulate temperature and run energy-intensive equipment. A lunar base needs an actual fission reactor, in which neutrons split uranium nuclei and sustain a controlled chain reaction.

NASA and its partners had been studying a 40-kilowatt lunar reactor, approximately enough to power an office building. The newer plan calls for 100 kilowatts. That is tiny compared with a terrestrial power plant but enormous by space standards: an order of magnitude more powerful than any reactor previously launched beyond Earth. Experts tell Andrews that building such a machine on an accelerated schedule may be possible. Their concern is that the schedule could encourage shortcuts in design, testing and safety.

Lessons from Orbit

The history of space reactors explains why caution matters. The United States launched an experimental reactor called SNAP-10A in 1965. It operated for only 43 days before an electrical component failed, and it remains in orbit. The Soviet Union launched more than two dozen reactors, mostly without incident. But one satellite, Kosmos 954, fell back to Earth in 1978 and scattered radioactive debris across a large stretch of northern Canada.

That accident suggests a straightforward safety rule: do not activate a lunar reactor until it has landed. Fresh uranium fuel is chemically toxic but relatively unremarkable as a radiation hazard. It becomes far more dangerous after fission creates highly radioactive by-products. The fuel should also be designed to remain contained if a launch fails. Andrews highlights TRISO fuel, whose small uranium-bearing pellets are wrapped in tough carbon and ceramic layers. A failed launch would still be expensive and messy, but resilient pellets could greatly reduce the chance of radioactive material spreading over a wide area.

Landing is only the start of the challenge. The moon has essentially no atmosphere, and temperatures can swing from about 250 degrees Fahrenheit during the day to minus 208 degrees at night. A terrestrial reactor often uses water to transfer heat and make steam, but water behaves awkwardly in low gravity and could freeze or expand violently in lunar conditions. A moon reactor may instead use air brought from Earth to drive a turbine. It would still need large radiating fins to shed excess heat into space because there is no atmosphere to absorb it.

Those fins would be exposed to micrometeorites moving at extreme speed. Larger impacts, though rarer, could damage an entire site. Burying the reactor in one of the moon’s lava tubes could provide useful protection. Moonquakes create a different structural problem. They are generally weaker than major earthquakes, but the moon’s dry geology allows shaking to persist for hours. A reactor must withstand long tremors that could damage components or move fuel into an unsafe arrangement.

Failure and Competition

The most realistic lunar nuclear disaster may not look like a terrestrial catastrophe. Modern reactors are designed to contain melted fuel rather than explode. Even so, a meltdown near the lunar south pole could leave a radioactive wreck that nobody could approach for generations. If it contaminated a reserve of polar ice, it could ruin one of the resources that makes a base useful in the first place. Lunar ice could supply drinking water, support crops and be split into hydrogen and oxygen for rocket fuel.

The more immediate danger to astronauts is a loss of power. If a reactor fails during the long lunar night, batteries may not last until sunlight returns. Life support and heating could shut down in a place where crews have few options for escape. Reliability is therefore not a convenience or a matter of cost. It is part of the base’s survival system.

Andrews closes with the geopolitical pressure behind the schedule. The Outer Space Treaty says nations cannot claim territory on the moon, but a reactor would create a practical keep-out zone around sensitive equipment. A nuclear-powered base could also establish de facto control over valuable terrain, especially areas near water ice. The United States and China both have reasons to move quickly, and both could treat reactors as more than power plants: they could become markers in a competition over lunar access and norms.

That makes careful deployment more important, not less. A lunar reactor could support a scientific village, a fuel depot and a staging point for deeper exploration. It could turn a temporary landing site into durable infrastructure. But the first reactor will also set expectations for how nations communicate, coordinate and protect the moon’s limited resources. The technology is plausible. The real test is whether the race to build it leaves enough room to ask the question Andrews returns to throughout the article: what happens if it goes wrong?