Why on Earth would NASA build a nuclear reactor on the Moon?

"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 oth...