XKCD: When Physics Is Funny

What if you took a dip in a nuclear reactor’s storage pool, where discarded fuel is kept for years until it’s not so radioactive anymore? Could you survive?

This is the kind of random question Randall Munroe, 29, creator of the massively popular web comic xkcd, answers every week for What If?, his spin-off project that poses oddball science questions. It’s not easy for him: tackling these outrageous hypotheticals is like facing off against a Hydra of nerdy curiosity–when one question is answered, three more pop up in its place.

In the question above, one might want to know: When do the fuel rods in the pool become dangerous? (When you’re close enough to touch them.) Wouldn’t the heat kill you first? (No, the pool’s not even as warm as a hot tub.) How long can decent swimmers tread water, anyway? (From 10 to 40 hours.) After figuring all that out, Munroe called a friend who worked at an actual reactor to fact-check. “He said I’d die before I reached the water,” Munroe explains. “From getting shot.”

On Sept. 2, the former NASA roboticist answers another question: What happens after you spend two years investigating ridiculous things like robot apocalypses and solar-powered cows? Answer: You graduate to a book. What If? Serious Scientific Answers to Absurd Hypothetical Questions includes old favorites, new inquiries and the mix of expert research and accessible wit that has made Munroe a favorite among both geeks and laymen.

“People often say, ‘I like your comics, even though I don’t know enough math to get all of them’–as if it’s some kind of club where they don’t belong,” Munroe says over email. “There’s no club. There’s just lots of people who are excited about thinking, learning, joking and sometimes overanalyzing things. No two people have exactly the same interests, and that’s fine. We can still be friends. Maybe we’ll learn things from each other.”

The web comic began in 2005 after Munroe, then a physics student at Christopher Newport University in Newport News, Va., scanned and uploaded his doodles. After a stint at NASA, he devoted himself full time to the comic and its fans in 2006. A year later, the site’s sarcastic take on math and Internet culture was drawing nearly 70 million hits a month. He started What If? in 2012, inspired by an experience teaching high schoolers. Munroe’s physics lecture didn’t wow the kids at first, but once they tried more colorful applications–like calculating the energy expended in movie scenes–enthusiasm spiked. “What I took from it was that people would get excited about applying these analytical tools to questions if the questions were interesting,” he says.

Munroe has published a comic compilation before, but he may not seem like a natural fit for the book world, given his tendency to push the boundaries of digital storytelling. One xkcd comic from 2013 slowly turned into a 3,099-frame animation over several months; another from 2012 allowed fans to explore a massive click-and-drag world that would be an estimated 46 ft. wide if printed out.

But Munroe doesn’t see jumping from the most interactive medium (the Internet) to the least interactive (dead trees) as a challenge. “A fun story is a fun story, whether it’s on a Kindle or a hardback book or a web page or an audio recording or in snippets on your iPhone,” he says. And books have upsides too: “If you accidentally lose your place, you don’t have to click More hundreds of times to get back there.”