The science of 'The Martian': What checks out (and what doesn't)

Mark Watney on Mars in The Martian.
Mark Watney on Mars in The Martian.
Image: Courtesy 20th Century Fox. - TM & © 2015 Twentieth Century Fox Film Corporation. All rights reserved.

How would you react if you found yourself stranded on an uninhabitable planet, without another living soul? Would you panic? Would you know what to do?

Fictional astronaut Mark Watney does.

In the new movie The Martian, Watney (Matt Damon) is stuck on Mars, alone on a cold, dead planet without a way home or enough food to survive. While most of us would crumble under even less dire circumstances, he manages to pull himself together and "science the shit" out of his predicament.

That may seem unreasonable — but at its heart, The Martian has a deep understanding of how astronauts really behave in serious life-or-death situations.

What it got right

Instead of panicking, Watney stays calm to assess his situation. It's a personality trait that NASA scientists recognize in their actual astronaut colleagues.

"We have astronauts that are very much like that," Brian Muirhead, chief engineer at NASA's Jet Propulsion Laboratory, told Mashable. "You put them in a situation where there's an unusual problem or there's something going wrong, and they'll find clever ways to solve it with whatever they have handy."

Watney manages to survive using his own ingenuity. Jim Green, NASA's director of the planetary science division said he sees that kind of ingenuity "every day in the agency, in so many different ways."

Also true to life: Watney's reverence for the alien scenery that surrounds him. "There are wonderful moments, where even though Watney is in a struggle for his life on a daily basis, he sits on the edge of a crater wall and looks at a sunset because he can," Green, who advised director Ridley Scott for the movie, told Mashable. "It's beautiful. He revels in the environment that he's in."

What it got wrong

Before waxing too poetic about The Martian, it's important to note that not all of the science in the movie rings completely true to life.

For instance, Martian dust storms are more like a light breeze than a hurricane, as depicted in the movie.

Mars' atmospheric pressure is actually much lower than Earth's, meaning that wind speeds can only really get up to 60 mph at most, NASA says. (But where's the drama there?)

In spite of their relatively weak winds, Martian dust storms are still fascinating to the scientific community. Dust storms on Mars can sometimes go global, engulfing the planet in dust to the point that researchers on Earth can actually see the tempest through telescopes.

Mars dust is also notoriously sticky. Electrically charged particles of dust tend to stick to spacecraft and other objects that find themselves on the surface of the red planet, NASA said. Watney spends plenty of time cleaning off his solar panels in the movie, an activity that would probably ring true for any Mars explorer.

Watney also takes a moment while on Mars to admire a dust devil swirling in the distance. Those kind of smaller storms have actually been observed by NASA spacecraft at the red planet. (Watney also sees some lightning in the Martian skies, and believe it or not, lightning does crackle on Mars.)

There are other scientific issues with the movie as well. Astronauts would bounce on the real Mars, rather than walking around like they're still subject to Earth's gravity. And the spaceship that the crew uses to get to and from the planet is still firmly in the realm of science fiction.


Video: YouTube, 20th Century Fox

What it almost got right

Still, the truth is that most of the movie's (relatively small) science issues have a real scientific basis.

For example: Sure, it would be really difficult to get enough sunlight for the potatoes that Watney eventually grows within his radiation-blocking habitat. That said, Watney's ability to grow plants in the first place is based on real NASA applications in development today.

Plant scientists are currently working to create sustainable space farms that could accompany astronauts on a trip to Mars. They'd be used to cultivate food, possibly using Martian dirt, once the space explorers set up shop on the planet's surface, according to plant scientist Bruce Bugbee, who works on projects with NASA.

The ability to grow crops also changes the way people interact with their environments, Bugbee said. Watching something grow and helping to water it every day could have a positive effect on the psychological well-being of an astronaut very far from home.

"Plants have a profound psychological value for people in space, and you expect them to have some psychological value, but generally the value is greater than you might think," Bugbee said.

Which may explain how Watney manages to keep his wits about him for as long as he does.