10 Things to Know About Gravity

Director Alfonso Cua­rón’s latest film, Gravity, hits theaters today. The sci-fi flick is receiving rave reviews from critics and other filmmakers alike. Here are a few things you should know about the production. Warning: Spoilers below!

1. Its premise isn’t far-fetched.

Russia’s planned destruction of one of its own satellites kicks off the events in Gravity. Debris from that event destroys Dr. Ryan Stone (Sandra Bullock) and astronaut Matt Kowalski (George Clooney)’s shuttle and strands them in space. It might seem like no nation would ever do this, but, in fact, it’s actually happened: In 2007, China took out one of its own defunct weather satellites, sending a cloud of shrapnel “hurtling at nearly 16,000 mph along the main thoroughfare used by orbiting spacecraft,” according to Popular Mechanics. That debris joined the veritable garbage dump already orbiting above Earth, which consists of everything from rocket boosters to paint chips.

“On all of my missions, [we got] some warning from Mission Control about possible conjunctions—possible close approach by orbital debris,” former astronaut Tom Jones said at a special Popular Mechanics screening of Gravity. “You can see on radar everything that’s bigger than your fist. NORAD tracks it, and if you have to, you can maneuver the shuttle—even the [International Space Station (ISS)] has some small thrusters where it can nudge itself out of a critical path. So far we haven’t had any big impacts on human vehicles, but we’ve lost a couple of satellites from space debris.” Even small debris, traveling at those speeds, harms space infrastructure. Jones said the 2007 Chinese ASAT test doubled the debris risk to astronauts on the ISS. (Debris in space does eventually succumb to Earth’s orbit and burn up in the atmosphere, but depending on the size of the object and its orbital height, that process can take decades.)

The dangerous chain reaction of destruction seen in Gravity has a name: Kessler Syndrome, when there’s so much debris in space that everything crashes into everything else, creating more debris and therefore more collisions, rending space exploration too dangerous. It was a direct inspiration for Cua­rón and his son, Jonas, when they were writing the film.

2. It took 4.5 years to make…

Often, the only real things in a shot are Clooney's and Bullock’s faces. Everything else, from their space suits to Mother Earth, is computer generated. So Cua­rón and company created the entire film as animation first, working with sound effects, music, and lighting. “Then all that animation translated to actual camera moves and positions for the lighting and actors,” Cua­rón told Wired. “We did a whole exploration of the screenplay, every single moment; we made judgments about everything. Once we began shooting, we were constrained by the limitations of that programming.” The animation process lasted almost 2.5 years before they even began shooting with the actors.

3. ...and they had to invent new technology to do it.

“You want to pretend this is going to be easy,” Cua­rón told TheWrap. “Then it’s months and months of trying to figure out how. You come to the theory, and then you have to apply the theory, meaning to develop the technology.”

Among the new technology created for the film was a 12-wire rig devised by Special Effects supervisor Neil Corbould and his team that was controlled by puppeteers (from the play War Horse) to give the illusion that Bullock was floating through space; specialized rigs that could rotate or lift the actors at many different angles; and huge, computer-controlled robot arms typically used for car manufacturing that instead wielded cameras.

But the piece de resistance was what the filmmakers call the Light Box, a hollow cube with interior walls fitted with LEDs. The brainchild of Director of Photography Emmanuel Lubezki—who got the idea from LED lighting effects and projects at a concert—and visual effects supervisor Tim Webber, the Light Box was necessary because animators had to match up the lighting in the animation with the live action shoot perfectly. Cua­rón told ComingSoon that the finished box was raised on a six-foot-high platform and was 9 feet by 9 feet on the inside. It was fitted with 4096 LED bulbs that could show any CG image—the Earth, the sun, the stars—to get the correct lighting. According to The Wrap, about 60 percent of Gravity was shot in the box.

All of the technology could be synced with computers so that the filmmakers could move the universe around the actors.

4. Rejected strategies for filming "microgravity" included using wires and flying in the vomit comet.

Typically, wires have been used to suspend actors and give the illusion of floating, and Apollo 13 famously built sets and filmed inside a parabolic plane, which plummets for 25 seconds to create Zero Gravity. But though they were both considered, ultimately the filmmakers determined that neither would work because of Cuarón’s love of long takes (Gravity opens with a single, 15 minute shot). Bullock, who had signed on when the Zero G plane was still the plan, was relieved when it was scrapped. “I’m petrified of flying,” she told Vogue. “Plummeting out of the sky was not my idea of how I wanted to work with Alfonso Cua­rón. But at one point I sat down and said, ‘What is it about this movie that is telling me to get off my ass and get over something that has paralyzed me?’” Cua­rón said the system they eventually came up with was painful for Bullock, “but after not having to do the Vomit Comet, she was so happy, she didn’t care.”

5. Bullock trained to mimic movement in microgravity.

Her background as a dancer certainly helped Bullock pull off Gravity’s most difficult trick: Making it appear as though she was in microgravity. She worked with a pair of Australian dancers to retrain her body “from the neck down, to react and move as though it’s in Zero G, without the benefit of Zero G moving your body,” she told Collider. “Because everything that your body reacts to, with a push or a pull, and on the ground, is completely different than it is in Zero G.”

6. And she got advice straight from the ISS.

Bullock told Collider that Dr. Cady Coleman called her from the ISS to impart some advice. “I was able to literally ask someone who’s experiencing the things that I was trying to physically learn about how the body works, and what you do, and what I need to re-teach my body to do, physically, that cannot happen on earth,” Bullock said. “It’s just the oddest thing to reprogram your reactions. It was just a really coincidental, fortuitous thing that happened, over wine, that got me the final piece of the information that I needed.”

7. Cua­rón consulted with advisors, too.

The director very much wanted to make a film that was based in reality, with technology astronauts use today. (Even though the shuttle program has been discontinued, he made a decision to include it as a touchpoint for the audience.) He told ComingSoon that after he and Jonas wrote the first draft of the screenplay, they began involving experts because “we realized all the stupid things that we have described that would be completely implausible. Then, throughout the process, we kept on having advisors, not only NASA and astronauts and other people that are experts in different fields, but also physicists, trying to explain to us how objects react in micro-gravity and zero resistance. That was probably the toughest innovation, because what happens in micro-gravity and zero resistance is completely counter-intuitive.”

8. While taking liberties, the filmmakers tried to be pretty true to reality.

“We went through pains to make sure that the behavior of objects in micro-gravity and no resistance was as accurate as possible,” Cua­rón told the Huffington Post. At this same time, “this is not a documentary. We took certain liberties. Part of the liberties we took were in the sense of we would stretch the possibilities of certain things.”

There’s no sound in space, so Cua­rón mostly stuck to silence (there is a score, though). “The only sound you hear in space in the film is if, say, one of the characters is using a drill,” he told Wired. “Sandra’s character would hear the drill through the vibrations through her hand. But vibration itself doesn’t transmit in space—you can only hear what our characters are interacting with. I thought about keeping everything in absolute silence.” Another big no-no: Fires. “There’s no fire in space. At one point there’s an explosion, and the only fire you see is the bit that was inside the shuttle and then extinguished.”

9. Astronauts have given Gravity their seals of approval.

In the Hollywood Reporter, moon walker Buzz Aldrin wrote that “I was so extravagantly impressed by the portrayal of the reality of zero gravity. I was happy to see someone moving around the spacecraft the way George Clooney was. It really points out the degree of confusion and bumping into people, and when the tether gets caught, you're going to be pulled—I think the simulation of the dynamics was remarkable.”

At the Popular Mechanics screening, Jones called Gravity “probably the most realistic space film that I’ve seen,” pointing out that, in particular, the tethers outside the spacecraft in the film behaved as they do in real life. Jones told mental_floss that “When she’s moving inside the spacecraft, and she’s seeing things drifting around her, the helmet floating around, all of that was really realistic. That’s what was the most evocative of my experience.” Jones even watched a part of the ISS he helped build be destroyed, and said that the inside of the station was just as he remembered.

Not that the filmmakers got everything right: Aldrin notes that he and his crew weren't as carefree as Clooney's character, and Jones said that "in that initial collision, they’re bouncing around so much, your suit can’t withstand that—it would rupture," Jones said. "The movie would be very short! That's where they took some [creative] license." They also took a little license with the location of the orbiting spacecraft, placing the Hubble Space Telescope, the ISS, and the Chinese space lab Tiangong 1 all in the same orbit, when in fact, they're all in different orbits. In an interview with Space.com, the director said that "we did a draft where we tried to respect everything. Everything was just about explaining to the audiences all of that stuff, so we had to try to create a balance."

10. Even James Cameron loved it!

“I was stunned, absolutely floored,” the director and innovator told Variety. “I think it’s the best space photography ever done, I think it’s the best space film ever done, and it’s the movie I've been hungry to see for an awful long time.”