The film's space debris cascade is a very real possibility. This scenario is known as the Kessler syndrome, named after NASA scientist Donald J. Kessler who first proposed the theory in 1978. A cascading Kessler syndrome involving an object the size of the International Space Station would trigger a catastrophic debris chain-reaction. The orbiting debris field would make it impossible to launch space exploration missions or satellites for many decades.
The film is 90 minutes long. In real life, the International Space Station travels at approximately 17,500 mph, and orbits the earth every 90 minutes. The debris field also circles the earth every 90 minutes.
Aningaaq, the man Dr. Stone talks to on the shortwave radio, is the main character of the short film Aningaaq (2013) directed by Jonás Cuarón. In that movie he is an Inuit fisherman with a dog sled and a baby daughter, camping on the ice over a frozen fjord.
Alfonso Cuarón, cinematographer Emmanuel Lubezki, and visual effects supervisor Tim Webber decided they couldn't make the film they wanted using traditional methods. For the spacewalk scenes, says Webber, "We decided to shoot (the actors') faces and create everything else digitally." To do that, Lubezki decided he needed to light the actors' faces to match the all-digital environment. Whether the characters were floating gently, changing direction or tumbling in space, the facial light would have to perfectly match the Earth, sun and stars in the background. "That can break easily," explains Lubezki, "if the light is not moving at the speed that it has to move, if the position of the light is not right, if the contrast or density on the faces is wrong." Lubezki suggested folding an LED screen into a box, putting the actor inside, and using the light from the screen to light the actor. That way, instead of moving either Sandra Bullock or George Clooney in the middle of static lights, the projected image could move while they stayed still. The "light box", key to the spacewalk scenes was a nine-foot cube just big enough for one actor.
Various mechanical sounds made by the spacecraft are heard on the soundtrack as a result of conduction through the astronauts' bodies while they are in contact with the station. For example, when Ryan Stone is frantically trying to grab the handholds as she flies by the station, the sounds of the station are heard while she is holding a handle, and they cease when she lets go. On the actual moon missions the sounds of astronauts hitting their hammers on core sample tubes were conducted through their bodies and transmitted through their microphones.
The real-life Chinese Space station is named Tiangong, "Heavenly Palace." At the time of the film's premiere, it consisted of one small inhabitable module. The Tiangong program's goal is construction of a space station much like the one in the film by 2022.
To prepare for shooting, Sandra Bullock spent six months in physical training while reviewing the script with Alfonso Cuarón. Cuarón said, "More than anything else, we were just talking about the thematic element of the film, the possibility of rebirth after adversity." They worked out how she would perform each scene, and her notes were included the pre-visual animation and programming for the robots. Cuarón and Bullock zeroed in on Stone's breath, "and how that breath was going to dictate her emotions," he said. "That breath that is connected with stress in some instances, but also the breath that is dictated by lack of oxygen." Their conversations covered every detail of the script and Bullock's character. "She was involved so closely in every single decision throughout the whole thing," Cuarón said. "And it was a good thing, because once we started prepping for the shoot, it was almost more like a dance routine, where it was one-two-three left, left, four-five-six then on the right. She was amazing about the blocking and the rehearsal of that. So when we were shooting, everything was just about truthfulness and emotion." James Cameron, best friend of Cuarón and a huge fan of the film, said "She's the one that had to take on this unbelievable challenge to perform it. (It was) probably no less demanding than a Cirque du Soleil performer, from what I can see. There's an art to that, to creating moments that seem spontaneous but are very highly rehearsed and choreographed. Not too many people can do it. ... I think it's really important for people in Hollywood to understand what was accomplished here."
Because of Alfonso Cuarón's lengthy takes, Sandra Bullock had to memorize long combinations of precise movements to hit her marks at different points in the shot. She often had to coordinate her own moves with those of the wire rig attached to her and the camera.
Alfonso Cuarón and Jonás Cuarón developed the script at Universal Pictures. Universal hoped to attach Angelina Jolie to the project, but decided the film was too expensive, and put the film into turnaround. The film spent 4 years in development hell because the cinematography, visual effects, and realistic "story atmosphere" of outer space were too challenging. Alfonso Cuarón had to wait for technology to catch up to his vision. That finally happened in 2009, with James Cameron's Avatar (2009).
Although the film has received acclaim for its realism of its premises and its overall adherence to physical principles, director Alfonso Cuarón has admitted that the film is not always scientifically accurate and that some liberties were needed to sustain the story.
Actor Phaldut Sharma, who voiced as an goofy Indian astronaut, 'Shariff', chose the song "Mera Joota Hai Japani" for humming himself when the director asked him to play something light. The director thought the character would put the audience at ease and get a few laughs before the actual story kicked off. The lyrics of the song literally mean, "My shoes are Japanese, my pants are English, the red hat on my head is Russian, and yet my heart is Indian" - figuratively saying that an Indian, wherever he goes, whatever he eats or wears, at the very heart he'll always be an Indian. It is a classic Hindi song from Shree 420 (1955).
The spacesuit that Dr. Stone puts on in the Russian Soyuz capsule has the number 42 on the patch. This places the film between September 2014 and March 2015 as the Expedition number 42 will be underway on the International Space Station.
When the sequence of Stone entering the ISS (International Space Station) airlock and shedding her spacesuit was filmed, actor Sandra Bullock sat on a rig with a bicycle seat and had her right leg strapped into a two-part brace inside a specially-made chamber. She then mimed movements that were carefully choreographed and a camera rig was rotated slowly to create the illusion of her's and the ISS's rotation. Lights were also placed in strategic spots to capture the shining of the sun in the window. In post-production, Bullock's right leg and the braces were erased completely and recreated with CGI.
Kowalski mentions landing at Edwards, a reference to Edwards Air Force Base in California. It was the primary landing site for all shuttle missions until 1991, then a backup landing site until the Space Shuttle program ended in 2011.
When Matt and Ryan are making their way to the International Space Station, he finds out Ryan is from Lake Zurich, Illinois, and states that it's 8:00PM there. They are floating over Egypt where it is 3:00AM locally.
Dr. Stone states that she is in a Soyuz TMA-14M. The Soyuz TMA-14m is the spacecraft that launched the crew for Expedition 41. The Soyuz TMA-14M will most likely remain on board the space station for the Expedition 42 increment to serve as an emergency escape vehicle.
The trivia items below may give away important plot points.
A longtime rumor claims that NASA provides suicide pills to astronauts for worse-case scenarios. NASA has denied it for decades. Some people have said that it would be easier and more comfortable to reduce oxygen in the chamber, as depicted in the film.
Ryan's hallucination of seeing Kowalski again in the space pod was George Clooney's idea. According to Clooney, Alfonso Cuarón was unable to come up with a satisfactory resolution for the character despite many revisions of the scene, including removing the dialogue, until Clooney offered to take a shot at rewriting the scene himself.