The Transportation Secretary has directed NASA to start working on building a nuclear reactor on the moon by 2030, declaring it necessary to win the next space race.
https://www.politico.com/news/2025/08/04/nasa-china-space-station-duffy-directives-00492172
How would that even work in lunar gravity? And who’s gonna install it?
Considering the cost of each flight and how relatively little payload on each flight, WHAT A FUCKING STUPID IDEA!!!
I wonder who came up with this one?
To what end? How will the energy be transmitted to Earth? Don’t nuclear power plants require a lot of water? What about the treaties regarding the Moon?
This next question is going to show I am definitely not a physicist. What about the radiation from the waste products? Is that going to be contained to the Moon?
This is not a new idea, and the current effort of concept development of a small, portable reactor for surface power predates Sean Duffy:
However, NASA did specify that the reactor should stay under six metric tons and be able to produce 40 kilowatts (kW) of electrical power, ensuring enough for demonstration purposes and additional power available for running lunar habitats, rovers, backup grids, or science experiments. In the U.S., 40 kW can, on average, provide electrical power for 33 households.
NASA also set a goal that the reactor should be capable of operating for a decade without human intervention, which is key to its success. Safety, especially concerning radiation dose and shielding, is another key driver for the design.
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After Phase 2, the target date for delivering a reactor to the launch pad is in the early 2030s. On the Moon, the reactor will complete a one-year demonstration followed by nine operational years. If all goes well, the reactor design may be updated for potential use on Mars.
Beyond gearing up for Phase 2, NASA recently awarded Rolls Royce North American Technologies, Brayton Energy, and General Electric contracts to develop Brayton power converters.
Thermal power produced during nuclear fission must be converted to electricity before use. Brayton converters solve this by using differences in heat to rotate turbines within the converters. However, current Brayton converters waste a lot of heat, so NASA has challenged companies to make these engines more efficient.
Surface power production via nuclear fission is crucial for any long duration crewed outpost on the Moon because while most the surface is exposed to sunlight continuously for ~14 days, it is also in darkness for the same period, and the capacity for electric battery or other storage would be prohibitive from a weight and assembly standpoint. The same is true for outposts or settlements in the surface of Mars, because while it does have a day/night cycle just a few tens of minutes longer than Earth, it also has weeks-long dust storms (and about half the incident sunlight). Any crewed habitation at the orbit of Jupiter or further would certainly require nuclear fission (or fusion, when and if controlled fission ever becomes practicable) not only because of the reduced insolation at that distance but also for propulsion as chemical propellants just lack enough specific impulse to make a crewed journey possible in a reasonable amount of time.
Whether you think a human presence on the Moon (or Mars, or in interplanetary space) is necessary or even plausible with extrapolation of current technologies is another question entirely. But if you do, nuclear power (or other non-chemical and non-solar source)is the only way to sustain it.
Stranger
Fueled with what? Every gram of fuel will have to be lofted from Earth, transferred to cisLunar, and soft-land safely.
This would be a sealed reactor, a.k.a. a sealed microreactor, which would be delivered to the surface of the Moon as a unitary system, function for its service lifetime, and be ‘retired’ (effectively abandoned) in place.
Stranger
So, fueled once and then “decommissioned” somehow when exhausted.
Still, it’s a lot of mass to hoist, and if this isn’t some kind of silly once-off demonstration, repeatedly. It contributes nothing to a persistent and ongoing presence. Imagine if European powers had to furnish wood or coal to their North American colonies?
If you build your bases at the “peaks of eternal light,” which are found on high ridges and crater rims near the Moon’s poles you need a great deal less battery storage.
Do we have a vehicle that can take it in one shot?
The Europeans would have never tried to colonize the Americas if it consisted of bare, abrasive rock, no air or liquid water, and hadn’t already been extensively cultivated by the indigenous people who taught them where and how to extract resources and got smallpox, cholera, and massacres for their trouble.
These are scarce, near the poles (the most difficult place to land), and away from a lot of features of scientific interest. That might be feasible for a specific type of outpost but not generally useful, insofar as anything on the surface of the Moon is ‘useful’.
Hypothetically (if you believe everything Elon Musk says), the SpaceX Human Landing System based upon ‘Starship’ could do so. At least, if they can keep it from blowing up and raining debris all over the Bahamas.
Stranger
This is not necessarily a bad idea (or a dumb one).
If we’re looking to establish a long term unmanned station on the moon for observation and scientific testing, it’s going to need a power source to run its operations. And a small nuclear reactor is probably the best source in terms of a very limited ability to transfer fuel. A solar array might be an alternative but that could require a larger cargo space than an equivalent nuclear reactor would.
Wouldn’t a nuclear reactor require someone onsite to run it at all times?
Is there one on Earth run human free?
If you get close to (but not right at) one of the poles, you can run a single wire all the way around the Moon at a constant latitude. You can then distribute solar panels all the way around and about half of them will be in sunlight at any given time (assuming they are angled correctly). Current will flow and you can tap into it wherever you like.
You could even do this at the equator, although it would require a fairly long wire. Cheaper to just get within a few hundred km of a pole. The panels can all be designed with a structure at a fixed angle for commonality.
This is not a novel concept or without prior experience:
Who is going to physically deploy hundreds of kilometers of power cable or millions of square meters of solar panels and support structure in a vacuum. on a surface of fine, abrasive, electrostatically-charged dust?
Stranger
“Who will bell the cat?”
I ain’t saying it’ll be easy. But if you have a good-sized rover that can travel at 10 km/h or so, then you can accomplish it in several days. The wire doesn’t have to be populated with all panels immediately; you can start with a dozen.
Initially, for a small starter colony, a small, reliable reactor is a good choice. But eventually you want more power.
There’s no need to start with “millions” of square meters of solar panels, and the starter wire can be just a millimeter or so in diameter (needing only a couple tons of wire).
Panels can be added as time goes on without needing to increase the wire size. Each new panel increases the voltage on the wire but not the current. The panels would have regulators that keep a constant current while increasing the voltage up to their power capacity.
That’s putting it lightly. Glossing over the engineering and logistical details, not to mention the mechanical, electrical, and health impacts of dealing with the lunar dust environment is dispensing with many of the major challenges of building such an effort (or how you would power “a good-sized rover that can travel at 10 km/h or so”) make it all sound ‘easy’, but what is even easier is to land a single encapsulated nuclear microreactor that can power a facility for a decade without having to deploy and maintain any extended infrastructure. And while planning for infrastructure would be useful for a long term habitation strategy (although there are many, many reasons to doubt the viability of extended duration human habitation in Lunar gravity and environment) nobody is really making any detailed plans beyond some vague “2030’s” timeline.
Stranger
I’m not assuming anything in the rover design beyond what is already being planned or at least proposed. Specifically, the pressurized rover:
JAXA is suggesting a speed of 10-15 km/h:
I don’t know the nominal cargo capacity, but it has a target mass of 15 tons, so a cargo of a few tons seems plausible:
It’s intended to be powered with large, vertically oriented solar panels:
Of course, if it’s solar powered, then it had better be in sunlight. So perhaps it should target a month for the journey. That’s only 21 km/day for a circle 100 km from the pole.
Is all of this still highly speculative? Yes. But my proposal isn’t a great leap beyond that.
Considering the damage that the anti-science Trump administration is doing to our scientific and governmental infrastructure, I doubt we’ll even be capable of it, whether it’s a good idea or not. They people who can pull off such missions will be imprisoned, dead or fled to some other nation and replaced with loyalist incompetents.