“Duffy to announce nuclear reactor on the moon” is not a headline I imagined reading before last week. Sure, as a sci-fi loving nerd, I could see a future where nuclear power played a role in permanent Moon settlements. But the idea of NASA building a 100-kilowatt microreactor there in the next five years seemed ridiculous. Not so, according to scientists.
“I have no idea why this is getting so much play,” Professor Bhavya Lal tells me over the phone, with a hint of exasperation in her voice. Lal’s response makes sense once you understand the arc of her career; she has spent much of her professional life thinking about how the US should use nuclear power to explore space. At NASA, she served as the acting chief technologist, and was awarded the agency’s Distinguished Service Medal. Among her other qualifications, she also testified before Congress on the subject of nuclear propulsion, and even helped rewrite the rules governing launches involving radioactive materials.
Most recently, she wrote a paper titled Weighing the Future: Strategic Options for US Space Nuclear Leadership where she and her co-author, Dr. Roger Myers, examine the past failures of US policy as it relates to nuclear power in space and argue the country should test a small nuclear system on the Moon by 2030. The way Casey Dreier, chief of space policy at The Planetary Society — a nonprofit that advocates for the exploration and study of space — tells it, many aspects of Secretary Duffy’s plan are “pretty much straight out” of that report.
Lal is more modest and describes the directive Duffy issued as “accelerating ongoing work” at NASA. According to her, the agency has been “funding [space] fission power for years,” adding that the only new thing here is that there’s a date. “We’ve done this for more than 60 years,” she tells me, and if NASA ends up delivering on Duffy’s plan, it wouldn’t even be the first nuclear reactor the US has sent into space. That distinction goes to SNAP-10A in 1965.
The reason the US has spent decades exploring space-capable nuclear reactors is simple. “You can get massive amounts of power from very little mass,” explains Nick Touran, reactor physicist, nuclear advocate and the founder of What is Nuclear. And for launches to space, keeping payload amounts low is critical.
Just how much power are we talking about? “When fully fissioned, a softball-sized chunk of Uranium-235 offers as much energy as a freight train full of coal,” says Dr. Lal. Combined with the…