Weir has made a name for himself among hard-core sci-fi fans for his dizzyingly detailed explanations of the quantum physics, chemistry, engineering, aerodynamics and rocket science underpinning the plots in his novels. A question about a plot point will provoke a mind-warping answer, a barrage of arcane facts interspersed with self-effacing jokes and casual profanity. This is how conversations with Weir, 48, tend to go. “Project Hail Mary,” Andy Weir’s next book, is out on May 4. He eventually figured out the number he needed for a single sentence - 25.984 microns - and, in the process, learned a lot about neutrinos. But Weir has never been satisfied with fictional solutions to scientific quandaries. Most sci-fi writers would err on the side of fiction rather than science. “Neutrinos are the smallest and most difficult to deal with subatomic particles that we have ever actually managed to prove exist.”

I mean, we’re getting to the edge of human knowledge on that one,” Weir said in an interview last month from his home in Saratoga, Calif. “I was having a really difficult time finding information on that, and the reason is because people don’t fully know. He needed to figure out how much energy would be produced by two of those subatomic particles colliding. The book’s plot hinges on a space mold that devours the sun’s energy, threatening all life on Earth, and that propels itself by bashing neutrinos together. When Andy Weir was writing his new novel, “ Project Hail Mary,” he stumbled into a thorny physics problem.

Artemis by Andy Weir