AYESHA RASCOE, HOST:
So question for you. If you unleashed a T. rex in New York City, how many humans would it have to eat to meet its basic caloric intake each day? My next guest says just half an adult per day, or an entire 10-year-old. He estimates New York could sustain a population of 350 T. rexes. That's good to know, but we don't want to have to use that information. Randall Munroe's latest book is "What If? 2: Additional Serious Scientific Answers To Absurd Hypothetical Questions." He's a former NASA roboticist who's now a writer and a cartoonist. And he joins us from Washington, D.C. Welcome to the program.
RANDALL MUNROE: Hi. Thanks for having me.
RASCOE: So this is a follow-up to your first "What If?" book. And this is a book that is full of wild and fantastical questions in which you try to answer the questions with serious answers. So why did you decide to do another round of this type of book?
MUNROE: Well, after I did the first book, people who read the first book would start thinking of me when, I guess, they came across some question they were wondering about. They're like, oh, I bet this is something I could ask the guy who did that book. With this book especially, a lot of people who get asked, like, unanswerable questions by their kids would write to me and be like, hey, my kid asked me this thing, and I don't even know what to say about it. And so maybe you can try to give some kind of an answer.
RASCOE: See, yeah, because my kids ask a lot of questions and often, I just tell them, you know, be quiet. Just leave me alone (laughter). I'm working. But you actually take them seriously because there was, like, a question in one of the books, like, if a building had a billion stories, what would that look like? And you explained how that's not really possible to have a billion stories. You like to take these questions and really think about them seriously.
MUNROE: Yeah, because, like, that question about - you know, if you want to build a billion-story building, there are a bunch of reasons why you can't do that. We don't have materials that are strong enough to hold the building together. The Earth's rotation would actually fling the end of the building out, sort of like a kid on a merry-go-round. The building would break apart, and also the top of it would run into the moon. But a lot of the engineering problems that you'd run into in building this kind of building are sort of the same problems that we've run into with some slightly more serious projects, like these proposals to build a space elevator. And, like, those are the subject of really serious inquiry, and there are a bunch of unsolved problems. And so the little girl who wrote in to ask about that, I was like, if you want to work on this, the world could use some good solutions to some of these problems.
RASCOE: You deal with a lot of stuff. You deal with, you know, astrophysics, climate systems, a lot of dinosaur stuff. And as you mentioned, some of the questions are from kids. Did you find that there's a difference between the questions that kids ask and adults ask?
MUNROE: Yeah, I think that adults are, like, worried about looking like they don't understand stuff. And so adults will try to ask questions that are, like, showing how many cool things they know about. It's like they're - they have an answer in mind or something. They're - and they'll try to put in all these complicated elements about, like, what if you have a train going at the speed of light and then it goes into a Mobius strip and goes through a wormhole? Now, you put a nuclear bomb - you know, like, they'll build up this whole scenario of, like, trying to make cool things happen. And a kid just asks a really simple question, like, what if you filled the solar system with soup?
RASCOE: Yeah.
MUNROE: And, like, those end up being much more interesting questions 'cause the kids aren't trying to impress you. They're just, you know, asking a question that they don't know the answer to.
RASCOE: Something that you said in the book that I was surprised by was, can you destroy the moon with, like, whatever weapons or equipment we have on the Earth? I thought the moon could be destroyed. Like, there's nothing we have on Earth that could destroy the moon? Like, if we shot nuclear weapons or some type of something at it, we couldn't destroy the moon?
MUNROE: No, no, the moon - I mean, it's really big. It's small compared to the Earth. But, you know, you often hear people say, like, well, we have enough nuclear weapons to destroy the Earth. But, like, really, we have enough nuclear weapons to really mess up the surface of the Earth. But, like, the whole Earth - that's just too big. There's really nothing we can do to take that apart. And the moon, you know, if you look at it, it's covered in craters. That's like the solar system has been trying to destroy the moon for years, and all it's managed to do is put some, you know, circular scars on the face. So I think the moon's going to be around for a long time.
RASCOE: Do you have a favorite question and answer out of this book?
MUNROE: Someone asked what would happen if she stood on top of the geyser at Old Faithful when it erupted? Would I die or what would happen? How would I be injured? And this is a neat question because it made me realize I didn't actually know exactly, like - there was a lot of stuff about Old Faithful that I didn't know. I was thinking, OK, to answer this, like, well, wait, what is the stuff coming out of the geyser? Is it steam or is it, like, water? Is it like a Super Soaker in the ground? And then I realized I wasn't even sure if it's hot or not, you know? Like, is it hot water or cold? Because I know that it's powered by geothermal energy, but maybe the water's not hot. And so I got to go read about Old Faithful and learn about it.
The big thing I learned is you definitely don't try to do this. There's actually a long history of people being injured - like, tourists showing up and, like, being like, oh, I want to look down into the vent and see where the steam is coming out and then getting badly burned when it erupts. And so now they have, you know, fences around it and everything.
RASCOE: One line in your book that, you know, stuck with me is you - and you talked about this - is like, I like ridiculous questions because nobody is expected to know the answer, which means it is OK to be confused. Is that ultimately what you want readers to take away from the book - that confusion is natural, that that's a place where curiosity is born? So even - you know, to maybe kind of embrace the confusing, to try to figure out the answers.
MUNROE: Yeah, I really like showing people how I go into a question where I definitely, like, have never encountered this before. You know, it's not like something that some people know the answer to what would happen if the solar system was filled with soup. You know, this is, like - this is a new question. No one - and so I like showing, like, everyone's confused going into this. You know, we're all, like, starting from scratch. And I like to show how you can take these tools of science and math and apply them to these ridiculous questions and actually get answers - you know, showing how you - it's OK to be confused. Scientists are confused by things all the time, you know? But what's great about science is that it helps us, like, take something we're confused about, learn about it, get an answer, and then eventually not be confused. And then the same science that you use to answer these ridiculous questions, you can use to tackle serious and important ones.
RASCOE: That is Randall Munroe. His new book is "What If? 2: Additional Serious Scientific Answers To Absurd Hypothetical Questions." Thanks so much for talking to us today.
MUNROE: Hey, no, thank you. This was a lot of fun.
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