National Geographic : 2016 Dec
for the first time in my life experience, looking at storytelling in film, science was a character unto itself. AW: That was part of the goal. I didn’t set out to say, “People need to understand science more.” I was just like, “This is really cool to me. I want other people to feel that feeling.” NT: The movie takes place in 2035. That’s not a random time, presumably. AW: No. I calculated all the orbital trajec- tories that the spacecraft Hermes has to take to get from Earth to Mars and back, based on an ion propulsion drive that can provide a constant two millimeters per second per second [mm/s2] acceler- ation—which, as I’m sure you know, is way more than we can do right now. NT: These are real launch windows if we were actually to do this? So you have far more accurate information in this story than most people will ever know. AW: Yes. And in fact, some orbital dy- namicists actually double-checked my calculations, and I was only off by about 2 percent. That’s pretty big when you’re talking about interplanetary stuff... NT: But for fiction purposes... AW: It will do. NT: Right. So now you’re on Mars. Do you say, “I have to invent some non- realistic stuff to tell my story. I did everything else right, now give me some latitude”? You know what scene I’m thinking of in particular. AW: You’re talking about the sandstorm. NT: The dust storm. It’s never a sand- storm, because the air is not thick enough to carry sand. AW: Right. NT: For those who might have not seen the film: You have a spaceship that wants to take off, and there’s a dust storm—very common on Mars—whose pressure is so great that it’s tipping the spaceship. But the Martian atmosphere is so thin, and the mass of dust that it carries is so low, that a dust storm can’t tip over a spaceship. STARTALK AW: It cannot possibly. It could barely tip over a piece of paper. NT: And I’ve defended you, by the way. I’ve said, “Look, he needs it to tell the story. At least he got the fact that Mars has dust storms.” AW: Before I had the dust storm, I had a different idea, but this is a man-versus- nature story, so I wanted nature to get the first punch in. That was the most fun part: coming up with stuff to throw at him and figuring out how he’d solve it. NT: Did you feel at any point in the nov- el, “OK, this will actually kill him”? AW: Oh sure. There were lots of places where I came up with a problem that was so severe there was no way for him to survive. In those cases, I would either give him some piece of technology that enables him to solve the problem or I’d just have that problem not occur. NT: For me it didn’t matter whether I knew he was going to die or not. I’m invested in, Can he solve this problem? AW: That’s because you’re a geek, like me. It would’ve been a helluva shock if he had died at the end, right? It’s like a James Bond movie: He’s in constant life- threatening peril, but you don’t actually think he’s going to die. You’re really just curious how he doesn’t die. NT: Exactly. Cans full of film reels surround Andy Weir in a storage vault at the 20th Century Fox Studios in Los Angeles.