Why Martian Dust Storms Can't Knock Over Matt Damon

Why Martian Dust Storms Can't Knock Over Matt Damon

The astronauts struggle against the wind of the storm. Debris flies through the air. A large piece of equipment hits an astronaut (played by Matt Damon) in the chest and he is hurled away into the dark.

Weather makes many dramatic appearances in The Martian, the recently released movie based on the book by Andy Weir. And in 3D, both the weather and the Martian landscape are captivating. But would a storm like the one that starts the movie happen on Mars? The answer is both yes and no.

Dust storms do happen on Mars. Every few years there is a dust storm so monstrous that it covers the entire planet. The storms can last weeks or months.

Dust storms are caused by convection. Sunlight heats the surface of Mars. The planet surface heats the lower atmosphere. The upper atmosphere stays very cold. Warm air rises up and cold air drops down. The warm air takes the tiny particles of dust into the sky as it rises. This process is similar to how small thunderstorms happen on earth, but with dust instead of water vapor. On Earth the vapor condenses, forming clouds of a thunderstorm.

The winds in a Martian dust storm blow as fast as the winds of a Category 1 hurricane (average wind speed 74-95 mph). On Earth, that’s enough to knock a person over. But on Mars it would feel like a light breeze. 

What would knock a person over on Earth is the force of tiny, invisible air molecules. The Martian atmosphere doesn't contain as many molecules as Earth's atmosphere. For every 100 molecules of air near the surface of Earth there is only about one air molecule near the surface of Mars. That means that there isn't as much force. Martian winds can carry light dust - very small particles at the Martian surface - but they certainly couldn't carry Matt Damon even with less gravity.  

Spirit and Opportunity, the NASA rovers now exploring Mars, have been hit by dust storms. They are too heavy to be moved around but the dust does affect their work. It can block most of the sunlight so their solar panels can't be charged.

So the dust storm that starts off The Martian could not have happened. But that's why this is called science fiction!

Other parts of The Martian are so grounded in actual science it feels like we are really traversing the surface of Mars. In fact, NASA has a tool that allows you to see the Martian landscape featured in the movie. NASA has also put together information about technologies that could get us to Mars.

Once on the Red Planet, we would be able to experience for ourselves fierce winds that feel like a light breeze.