Why Gravity is junk science

The latest sci-fi film is so grounded in reality that Quentin Cooper hopes it forces us to start dealing with the real risk of space debris.

With its attractive heavyweight stars, it’ll pull you in and never let go. You’re certain to fall for it. It deserves to be massive.

The puns are, like the titular force itself, irresistible. And with a $200 million opening, it seems the same goes for the movie. What marks Gravity out from other science fiction stories is that it is built on a lot of solid science and only a touch of fiction, rather than the other way around.

Most blockbusters, science fiction or otherwise, take a pick’n’mix approach to the laws of physics – selecting just those that fit at any given point in the story (something Gravity star Sandra Bullock knows firsthand from the brilliantly ludicrous “flying bus” sequence in Speed). And most sci-fi is usually only “sci” in that it draws on scientific advances and theories to explore “what if” scenarios: what if we could travel in time, or go faster than the speed of light, or meet friendly aliens? The amount of genuine, accurate science involved is usually very limited.

Not that there’s anything wrong with exploring what ifs. The X-Men is not spoiled by knowing that evolutionary theory isn’t big on mutations that grant random superpowers. Nor is Superman any less engaging because we know humans can’t fly.

Gravity is an exceptional exception to all this fantasy overlaid with a thin veneer of science. Even though [spoiler alert] most of the action takes place in space and almost everything besides the actors’ faces has been computer-generated, it’s utterly grounded in reality. Everything from the decals on the spacesuits to our ever-changing Earth above which most of the action unfolds has been recreated in painstaking detail. Rather than dreaming up flights of fancy to rival the Millennium Falcon or Deep Space Nine, all the spacecraft and space stations you see on screen already exist. The Space Shuttle, the International Space Station, and China’s Tiangong 1 space laboratory have been digitally mimicked with more precision than even the aliens in the 1960’s television series Captain Scarlet and the Mysterons could muster.

Nitpickers may say this makes Gravity overly faithful to what was already in orbit when production began more than four years ago. As of 2011 the Space Shuttle has been retired from service, and Tiangong 1 is now effectively on death row, supposedly mere days away from being allowed to deliberately burn up during re-entry. This just means it’s more plausibly set in the near past than the near future.

Buzz word

Ensuring each frame has the smack of authenticity is remarkable enough, but this is a moving picture, and what is even more impressive is how convincingly everything moves. Gravity isn’t just a vaguely sciencey title (in the vein of Quantum Leap, Red Dwarf, Event Horizon, Source Code, etc.). It’s a force to be reckoned with throughout the story. While most films cheat by having spacecraft with artificial gravity, or just keeping zero-G sequences to a minimum because they are a nightmare to shoot, this film embraces and explores every aspect of how objects and people are affected by it, particularly by the microgravity in orbit often called weightlessness, and the dangers it can pose.

And it does so accurately enough to satisfy even those who’ve been there. Among several astronauts quick to praise the film is second man on the moon Buzz Aldrin. He was “impressed by the portrayal of the reality of zero gravity. Going through the space station was done just the way that I've seen people do it…it really points out the degree of confusion and bumping into people, and when the tether gets caught, you're going to be pulled.”

Creating a compelling illusion of microgravity involved huge amounts of technical innovation, with cameras on computer-controlled robot arms, and actors filmed inside a cube kitted out with thousands of LED bulbs so that the light on their faces matches their CGI surroundings. This phenomenal attention to detail all serves to make something alien, or at least out of this world, tangibly real for the viewer.

All this attention to detail does not turn Gravity into a pseudo-documentary. It’s fiction with a lot of science, and is therefore science fiction, but not in the sense the term is usually used. It’s also a disaster movie. The disaster in this case is a chain reaction from a cloud of satellite debris flying round the Earth at thousands of miles an hour shredding almost everything in the same orbit. This might seem like the place where the fiction part of the science fiction kicks in, but in January 2007 China deliberately destroyed its own defunct weather satellite with a ground-based missile, creating thousands of pieces of space debris the size of a golf ball or larger capable of damaging anything in its path. Some of these objects have passed close to the International Space Station and earlier this year this space junk obliterated a small Russian satellite.

Gravity exploits the idea that as man-made debris accumulates in orbit around the Earth, collisions become more likely, potentially triggering an exponential increase in the number of waste objects (although this being fiction, it cheats by having key spacecraft in the same orbit as the debris). The theory was first developed in 1978 by Nasa scientist Donald Kessler, who feared a major collision could accelerate this process, leading to the wiping out of most of our communications satellites and the creation of a debris belt that would make it impossible to send anything new, manned or unmanned into space for decades. Kessler also inspired Pierce Brosnan’s character Professor Donald Kessler in Mars Attacks!

Should his predictions come to pass, instead of humanity continuing to explore ever further beyond Earth we will be sealed off from the rest of the cosmos inside a cocoon of our own space waste. Perhaps as well as providing audiences with a visceral and thrilling ride, Gravity will help us take that risk seriously and encourage us to start dealing with the debris. Or perhaps what goes around comes around and it’s only a matter of time before we pay for letting so much junk build up right in our own backyard.

If you would like to comment on this article or anything else you have seen on Future, head over to our Facebook page or message us on Twitter.