Science Goes to the Movies: 'Gravity' With the astronaut flick Gravity dominating box offices and dinner table conversation, Science Friday brings in the experts to fact-check. In our first installment of "Science Goes to the Movies," astronauts Jeffrey Hoffman and Don Pettit answer your Gravity questions and explore the real risks of spaceflight.

Science Goes to the Movies: 'Gravity'

Science Goes to the Movies: 'Gravity'

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With the astronaut flick Gravity dominating box offices and dinner table conversation, Science Friday brings in the experts to fact-check. In our first installment of "Science Goes to the Movies," astronauts Jeffrey Hoffman and Don Pettit answer your Gravity questions and explore the real risks of spaceflight.


UNIDENTIFIED MAN #1: The most spectacular science shocker ever filmed. Too real to be science fiction, now science fact.


That theme signals a new series we're calling Science Goes to the Movies. If you ever watch sci-fi flick and think, now, com on. Did that really happen? Well, to us, that's what this series is all about. We're going to ask scientists to put on their film critic hats and help us separate the fact from Hollywood fiction.

And this week, we're kicking it off with "Gravity." Alfonso Cuaron's 3-D space epic is in theaters now. And if you've seen it, you know Sandra Bullock plays astronaut Ryan Stone. And when the film opens, she's on a space walk, helping fix the Hubble Space Telescope and talking to George Clooney as things sort of get out of hand.


GEORGE CLOONEY: (as Lieutenant Matt Kowalski) Astronaut is off structure. Dr. Stone is off structure.

SANDRA BULLOCK: (as Dr. Ryan Stone) What do I do? What do I do?

CLOONEY: (as Lieutenant Matt Kowalski) Dr. Stone, detach.

BULLOCK: (as Dr. Ryan Stone) No.

CLOONEY: (as Lieutenant Matt Kowalski) You must detach.

BULLOCK: No. No, I can't.

CLOONEY: (as Lieutenant Matt Kowalski) If you don't detach, that arm is going to carry you too far. Listen to my voice. You need to focus. I'm losing visual of you. In a few seconds, I won't be able to track you. You need to detach. I can't see you anymore. Do it now.

BULLOCK: (as Dr. Ryan Stone) I'm trying.

FLATOW: Ah, Hollywood. You'll be glad to know that the last time astronauts actually fixed the Hubble things sounded just a little bit different. Here's a clip from NASA TV during the last Hubble tune-up.


JOHN GRUNSFELD: Ready to do it?

UNIDENTIFIED MAN #2: I'm ready, John.

GRUNSFELD: Let's go do this. Oh, this is fantastic. I'm going to love it here. It looks nice. Woo-hoo.

FLATOW: That type of drama of Hollywood. That was astronaut John Grunsfeld serving - servicing the Hubble in 2009. So how realistic is "Gravity"? And are the disasters that we see on screen Hollywood exaggerations or, well, could they really happen? How close does the movie's 3-D magic come to the real space experience?

We recruited two astronaut film critics to help us answer the questions. And they're both SCIENCE FRIDAY returning champions. Jeff Hoffman is a former NASA astronaut. He's now a professor of aerospace engineering at MIT. He actually spent many hours outside the space shuttle fixing the Hubble decades ago. He joins us from Cambridge. Welcome back to SCIENCE FRIDAY, Jeff.

JEFFREY HOFFMAN: Ira, always good to talk with you.

FLATOW: Thank you very much. Don Pettit is a NASA astronaut at the Johnson Space Center in Huston. He's a veteran of many months aboard the International Space Station. He joins us. Welcome back to the program.

DON PETTIT: It's a pleasure to be here, Ira. And I'm going to have to stop meeting Jeff through your radio program, and actually talk to him face to face sometime.


FLATOW: Well, it's all technology, but it works. So let me remind everybody that this is SCIENCE FRIDAY from NPR. All right. Let's - Jeff, put on your critic's hat. What do you think of the film?

HOFFMAN: Well, I went to see it with 20 of our graduate students who recruited me. They said, oh, Professor Hoffman, you got to come with us and make a list of the things which didn't look right. So I did. I have to say, though, before starting to quibble, it was a spectacular movie. And I'm recommending it to anybody who asks, because they did a wonderful job, I think, of evoking some of what you see and experience in orbit - the sense of weightlessness, the views of the Earth.

But having said that, I'm glad that when I was working on the Hubble telescope, I had a much - I mean, we had our series of problems but nothing like Sandra Bullock. I mean, they had what you would call a monumentally bad day. Now, having said that, they were kind of stretching the boundary of physical reality in order to get some of the plot elements. As an example, orbital debris is a very serious problem. I mean, all space-faring nations, all companies that operate satellites are concerned with it. And destroying a satellite, which the Chinese did, we've - and the Russians have both done in the past, can actually lead to chain reactions not nearly as fast as occurred in the movie, but they would be limited to low Earth orbit. It would not take down all of the communication satellites, which are 20, over 20,000 miles above low Earth orbit.

And so the idea that the astronauts were completely cut off from the ground, that wouldn't have happened. And then, of course, it would be great if we could fly easily from the Hubble Space Telescope to the International Space Station to the Chinese space station, like they did in the movie; very important as a plot element. But orbital mechanics just doesn't work like that.

And I guess, the last thing - and there are many things we could talk about - but when Sandra Bullock - had she really been in a space suit, when she got out, she would not have just been dressed in a skimpy t-shirt and bikini shorts. She would have been wearing a full set of thermal underwear both to keep warm when it's cold at night and to keep cool when it gets hot during the day, socks, gloves. But on the other hand, who's complaining, right?

FLATOW: She had to match Sigourney Weaver in "Alien," right? That's simply...

HOFFMAN: I - that - I thought that kind of evoked that same thing, yeah.


FLATOW: 1-800-989-8255. I - instead, Don, getting to your impressions, I want to just go to the break because I want to come back, and I know you've spent over a year International Space Station. I want you to tell us what your comparison about your experiences in that space station were and compare them to what we saw in the film. I also want to talk a little bit, when we get back, about the Chinese space station and whether they really had a ping pong table in the Chinese space station because I swear I saw a ping pong paddle floating around inside. Maybe we'll get the answer to that. Maybe it's just some eye candy for the movie. 1-800-989-8255 is our number. You can call us if you want to talk about "Gravity" with Jeff Hoffman and Don Pettit. Also tweet us, @scifri. We'll be right back after this break.

I'm Ira Flatow. This is SCIENCE FRIDAY from NPR.


FLATOW: This is SCIENCE FRIDAY. I'm Ira Flatow.

We're talking about science going to the movies, about the new movie "Gravity" with my guests who are astronauts, former astronaut Jeff Hoffman and current astronaut Don Pettit. Our number, 1-800-989-8255.

Don, International Space Station, does it look like that?

PETTIT: It does look like that.

FLATOW: Well, you got to tell me a little bit more about it.


PETTIT: OK. Well, first of, you have to realize that Hollywood is not reality. It's an artistic distortion that makes us think about our place in reality. And once you get through that thought, then you can watch a movie like "Gravity" and enjoy the story that it has to tell because this is a story about our current space program. It's not what happened 40 years ago. I mean, this stuff is on orbit, and exciting things are happening every single day.

FLATOW: Yeah. Do you think this is positive, that the space people like this movie? Or is it a negative? It will - will it encourage people?

PETTIT: I think the, you know, people who understand the physics of what's going on are already captured by the space program. So, you know, you don't need to try to entice those people. In fact, what you could do - and, Jeff, this is something you could do with your students - turn the technical oversights in this movie into a homework problem for your engineering and physics students.

And that way, they can work out - actually the mathematical equation is tough. So, why they shouldn't it be the way they depict it. But for everybody else that isn't you know, an uber geek, a technical uber geek, this movie gets them to think about where they might be in a program if they were to be in space. And I think that's one of the main purposes of Hollywood, is to get us to think about our place in whatever reality the movie is trying to depict.

FLATOW: Mm-hmm. Jeff, you agree?

HOFFMAN: Well, and like I mentioned before, I think the movie did a superb job through this cinematographic magic of evoking the sense of being in space. And, you know, the visual impact of looking at the Earth, of seeing the Hubble Space Telescope, the International Space Station, they used real images, to start out with, which is why it looks so realistic. And then, of course, they worked their Hollywood magic.

I mean, it was a little bit disconcerting to see the Hubble telescope reduced to rubble in a few seconds after, you know, having worked so hard to fix it. But nevertheless, as Don says, it's a movie. And the other thing I should mention in terms of - they had to make some compromises to that people would understand what was happening. For instance, when George Clooney was flying around with his jet backpack, you wouldn't really see the exhaust coming out of it because it's just cold gas.

And when you saw those clouds of orbital debris approaching, I mean, in orbit, we're moving five miles a second, 18,000 miles an hour. So if there's a piece of debris coming your way, you're never going to see it before it hits you. But from the Hollywood point of view, they wanted to evoke the sense of impending doom with the approaching debris cloud, and it was very effective.

FLATOW: Don, you actually had a close call with some space junk on your last mission, did you not, on the Space Station?

PETTIT: Yeah, we did. And normally, folks do a good job here on Earth of tracking the space debris. And every once in a while, they'll get a surprise, and we don't have enough time to physically adjust the orbit of the Space Station to avoid the debris. And so the only thing we can do is hunker down in our Soyuz spacecraft and hope that the debris doesn't hit station. And that's what we did.

And it happened on a Sunday morning. You know, it seems like the only thing Hollywood missed in terms of the - all these maladies is that every time I've had a malady in space, it's always been early on Sunday morning when we had a small chance of sleeping in.


FLATOW: One thing I wondered about, remembering the Gemini mission - I think it was Neil Armstrong's Gemini mission - where they were practicing docking, and it was tumbling out of control with a stuck thruster and Neil managed to wrestle that thing back from spinning. But they talked about this in the '60s. Had it gone on much longer, that he would have lost consciousness. And I'm watching the movie and I'm seeing Sandra Bullock spinning out of control so much wondering did they get that right? Would she have lost consciousness by now?

PETTIT: You know, I don't know about that. I do know that if you're spinning like that the world seems to be going around pretty quickly.

FLATOW: Jeff, any thoughts on that?

HOFFMAN: Well, yeah, that was actually Neil Armstrong and Dave Scott, and they had a malfunction with their Gemini capsule. And they were spinning much faster than Sandra Bullock was though. I think they were spinning, you know, they were going around, you know, almost once per second.

And she could've gotten a very serious case of vertigo, and it can be very disconcerting spinning around. I mean, just being in space in a space suit outside numerous astronauts have reported a sense of vertigo. And you start spinning like that and there's no up and no down. She would've been completely totally lost. So the fact that she sounded a little bit panicky in the initial moments was, I think, very realistic.

FLATOW: Well, I say, is it possible the amount of banging they did against the equipment, the space station and...

HOFFMAN: That kind of bothered me. They sure put a lot. They put their space suits through a pretty tough test there, and normally, when you're moving around in space we always advise the rookie astronauts, you know, move slowly, don't bang around. On the other hand the circumstances under which they were moving, when you're approaching something and you have one chance to grab on or else you're lost in the universe, well, you sort of take what you can get.

FLATOW: Not to mention the...

HOFFMAN: But they were banging around an awful lot there. That kind of bothered.

FLATOW: Yeah, without ripping up the suits or getting a...


FLATOW: ...concussion or something from the impact. Did you notice that too, Don?

PETTIT: Yes, they were banging around, but I agree with Jeff that under the circumstances, I probably would've been doing the same thing. If I had one...


PETTIT: ...chance to grab on to something whizzing by I'd be working pretty hard about doing that.

FLATOW: Let's go to the phones. Alexis in Cedar Falls, Iowa. Hi, Alexis.

ALEXIS: Alexis: Hi.

FLATOW: Go ahead.

ALEXIS: Although the movie was visually stunning and I saw it myself in 3-D and it was great, but just as far as the dialogue went it didn't really register as very astronaut-like to me And I didn't know if they thought that maybe George Clooney's character was a little bit over the top, and I don't know because I've never been in that situation, of course, but what they thought of the dialogue of the movie.

HOFFMAN: I think that's a good point, actually. I caught on that at the very beginning when Sandra Bullock was working on the Hubble telescope. And, I mean, first of all, if there were another - there were two other astronauts out there at the time, which is unusual to start with, but it's physically possible. We have done it once, but they were just sort of lolling about, you know, having fun.

You don't really do that. I mean, when you go out on a space walk, you go out because you have useful work to do. And, you know, George Clooney was just sort of flying around, doing circles around Hubble and the shuttle and that wouldn't happen. And the language was also, I think, what we would call a little bit unprofessional. But again, it is a movie and they were trying to create the character.

It was a little bit strange that Sandra Bullock reportedly had only been put on the mission a few months before. I mean, normally to go out and use a space suit and work on Hubble, you'd want a rather experienced astronaut. And the fact that George Clooney didn't even know what town she was from after they presumably should've been training together for a long time that was maybe a little strange.

FLATOW: Don, George plays veteran astronaut, Matt Kowalski. You get the sense he doesn't really want to come home.

PETTIT: I could identify with that.

FLATOW: In what way?

PETTIT: Well, just I've spent two missions, each about six months, and when it's time to come home, you go gulp. You know, you hope your mission can be extended, and actually that happened with both of my missions for two separate reasons. And you're secretly hoping that you can stay for just a little bit longer, that you don't have to come in from playing anymore.

HOFFMAN: Space flight could be addictive, Ira.


HOFFMAN: I don't know how you feel about that, Don.

PETTIT: Yeah, it is. And you certainly miss your family and you wish you could drag your family up there. I bet my boys would do great. But in terms of coming back to earth, you know, I feel like I'm born to be in the space frontier, and space is where I really blossom and that's where, I think, I can make my greatest contribution to our country right now is being in space.

FLATOW: Would you go to Mars?

PETTIT: I'd go to Mars, but not on a one-way suicide mission. I'd immigrate to Mars if there was a chance that you could live the rest of your natural life or if it was going to be a mission that had some end where you were coming back in a couple of years, but not on some of these proposed suicide missions where you get there and 30 days later you run out of life support and everybody's dead.

FLATOW: Jeff, let's talk about that space debris up there. The Clooney character says: It's coming around in another 90 minutes. Again, is that how it works?

HOFFMAN: Oh, yeah.


HOFFMAN: Although again, the orbital mechanics of what was going on there left something to be desired, but things do orbit in 90 minutes, and I remember once on a flight we dumped some water overboard and the water instantly turns into ice crystals. So it's like having a blizzard going outside the window. And about 90 minutes later, I was looking out the window and here were all these little - it looked like snowflakes falling down. We had basically flown through our water cloud again. So, yeah, that was actually correct.

FLATOW: Could that be what...

HOFFMAN: There were some people who did some real - there was a lot of research that was done.


HOFFMAN: A lot of the nomenclature about the technical parts of the space station were really quite accurate, so somebody did some good research on the film.

FLATOW: And the tools, they look like your tools?

HOFFMAN: They did. Yeah, I think they were-again, they did a good job of evoking what it was like, how we work, within the limits of the story they were trying to tell, of course.

PETTIT: And one of the things I thought, Ira...


PETTIT: ...that they did was show that there are real risks when you're off in the frontier like this, and - because NASA makes these things look easy. We work slow and tedious and we try to avoid what you see there as excitement in a Hollywood movie. But they covered two out of the three big gotchas on the Space Station all in the course of about an hour.

FLATOW: 1-800-989-8255 is our number, talking with Jeff Hoffman and Don Pettit on SCIENCE FRIDAY from NPR.

What would you change? Would you change anything if there's a - you know, I'm sure they've destroyed everything up there. There's not going to be a sequel to this.

Well, I was going to say that there should be a sequel...


PETTIT: ...and you never want to underestimate the creativity of Hollywood in generating sequels.

FLATOW: What would you do if you were the producer or the...

PETTIT: Oh, this is easy. Opening scene, OK, they just completed International Space Station II and they're getting ready to dedicate it, and George Clooney's twin brother, the non-evil twin brother who maybe is a cellist in the New York Orchestra and completely non-technical, they're flying him up to Space Station for both the dedication and a memorial service for all the other folks.

And, you know, that's the first three minutes of the movie, and now you can have two hours of exciting terror following that.

FLATOW: I think you're in the wrong business, Don. Well, yeah, of course you could use George Clooney again because it's his twin brother.

PETTIT: Yes, of course. And then see, then you would arrange it so that his non-evil twin, which of course, you know, that's what made Clooney in this movie. So his non-evil twin, completely non-technical and then they could, you know...


PETTIT: ...carry it from there and go on with another two hours of excitement.

FLATOW: Let me ask both of you in closing minutes. How does this movie stack up against all these space movies? Jeff, what is your favorite movie? Does this stack up against it?

PETTIT: My favorite movie is still has to be "2001," and the reason, although the special effects can't compare, I mean, it was done back in the late '60s, but it was a movie that had a philosophical twist to it. And you left the movie really thinking about what have I seen, what's the significance of it?

I mean, "Gravity," visually it's spectacular, and really nonstop excitement from beginning to end. But once it's over, it's not something that you're going to be thinking about. You know, after "2001" people were constantly talking about what was going on at the end there? What did it all mean? And that to me is the essence of great science fiction.

FLATOW: Don, you agree?

PETTIT: "2001" is my favorite science fiction movie as well, and partly because it's the only movie that I'm aware of in recent times where when they're depicting scenes in space it's absolutely quiet, because as we know sound won't carry in a vacuum.

FLATOW: It's the old line: No one can hear you scream in space.

HOFFMAN: Well, we sure heard Sandra Bullock screaming at the beginning scene. She was screaming a lot. And as I said, I can't really blame her. I mean, that would be an absolutely terrifying thing is - and, if fact, one of the things that we really work hard to protect against is falling away from the shuttle or the Space Station and drifting off in space.

That's why all astronauts actually have little jet packs attached to their backpacks. So if they do fall off they can fly their way back. She didn't seem to have one in this movie, but there we go.

FLATOW: Don will write it into the next one. Thank you, both. Thanks, Don, for your time there at the airport. I know you're waiting to leave LaGuardia. So, Don Pettit, a NASA astronaut at the Johnson Space Center in Houston; Jeff Hoffman, former NASA astronaut, professor of aerospace engineering at MIT. Thanks for taking time to be with us. We'll going to get your next movie up for you to critique.

PETTIT: OK. It's been a pleasure, Ira.

HOFFMAN: Always a pleasure, Ira.

FLATOW: Thank you. Always a pleasure...

HOFFMAN: Bye-bye.

FLATOW: ...with you guys. And you can see Don Pettit's footage from the International Space Station at our website. And does it look like the Space Station in "Gravity?" You be the judge. You can watch it at

BJ Lederman composed our theme music, with help today from NPR librarian Kee Malesky. Go to our website at We're tweeting all week long, and you can join a group over there and download our app at both Android and iTunes and Apple app. Have a great weekend. Enjoy the movie. You know, see it in - if you go see it in IMAX it gets you a little nauseous so be ready for that. Everybody I've seen - but you can enjoy it any other way. It's a great film. We'll talk more about it. Have a great weekend. I'm Ira Flatow in New York.

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