One of the most enjoyable parts of being an unapologetic nerd is the satisfaction that can be won by tearing apart bogus science in movies. Whether you are laughing at the impossibility of humans producing more energy than they consume in the Matrix or you are on the level of Neil DeGrasse Tyson who shamed director James Cameron for digitally producing the wrong constellations in the night sky in Titanic, there is a certain sick thrill in pointing out the details that writers and directors overlook (seriously though, why no feathered dinosaurs in Jurassic Park?).
Cynical movie-goers with a nerdy flare may however be disappointed in this regard by the latest science-fiction blockbuster: The Martian. While not every detail of the movie (based on a fantastic book by former computer engineer Andy Weir) is completely based in reality, the story integrates a surprising number of real NASA technologies. From Matt Damon’s emergency potato farm to the vehicle he uses to explore the red planet, NASA is hard at work creating the technology that will be needed to allow humans to survive on another planet.
In the book/movie, astronaut Mark Watney survives an accident that leaves him stranded on Mars after his crewmates evacuate. Watney is fortunate to have access to a base of operations known as the Hab. Astronauts today train for long duration space missions using the Human Exploration Research Analog (HERA) at Johnson Space Center in Houston. Surprisingly, the real life version is a little more comfortable than Hollywood’s take on it. While Watney’s Hab is a single story affair made up of one large room with bunks, the HERA is a two story environment that provides living quarters, workspaces, hygiene modules and a simulated airlock. You’d think that 20 years in the future NASA could spring for the extra walls.
Food and Water
While the book and movie might take things a little further than current science has been able to achieve, we are well on our way to being able to produce both food and water in space. In 2014 astronauts in low-Earth orbit successfully planted the first ever extraterrestrial lettuce crop which they were recently able to harvest and taste. This marks a huge step towards sustaining astronauts for seriously long-term missions to other worlds. In terms of staying hydrated, Watney’s water reclaimer is a good stand-in for the technology already used on the International Space Station (ISS) which collects all the waste water from the day-to-day operations and from the astronauts own bodies, filters it and redistributes it. It’s not an exaggeration to say that astronauts end up making coffee with the water that left their bodies the day before.
In The Martian Mark Watney is lucky to have an “oxygenator” that pulls carbon dioxide from the air and supplies him with a steady stream of oxygen to breath. In real life we aren’t quite at the same level of sustainability, but NASA has managed to come up with a system that works well using a semi-closed loop. Astronauts on the ISS rely on the less cooly named Oxygen Generation System which uses electrolysis to separate the hydrogen from the oxygen in water by running a current through a sample. The oxygen is cycled back into the air while the hydrogen is pumped out into space. The system does, therefore rely on new water to keep it going, a problem that will have to be solved before we start shipping people to Mars.
Near Miss – Radioisotope Thermoelectric Generator (RTG)
One aspect of Mark Watney’s odyssey that features prominently and isn’t quite right is his misadventures with the missions RTG. The RTG is a source of power generation that in the book, movie and in real life uses radioactive plutonium-238 to create energy from heat. Plutonium-238 is ridiculously radioactive and becomes quite hot all on its own. In the movie, this causes problems for Watney as NASA protocol calls for him to bury the system far from the Hab as its radioactivity could fry his DNA. In real life Plutonium-238 is dangerous, but not quite that dangerous. The radiation it gives off wouldn’t be able to penetrate a space suit or even human skin. Actually the thin atmosphere on Mars would make radiation from the Sun a bigger threat to Watney than the RTG, which can generate a little more electricity than it takes to run an incandescent lightbulb.
All in all, The Martian does a better job than most science fiction stories at keeping things real. There are a tonne of other elements from the movie that are true and we just didn’t have the space to share. For a more comprehensive list, check out this article by NASA themselves. If you’ve got NASA giving you props on the technology in the movie you made, you’ve probably done a pretty good job. Even better, Andy Weir managed to take the potentially boring science behind space travel and turn it into an awesome story.