The Challenges of Building a Colony on Mars

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In this series, mental_floss will examine the engineering problems associated with humanity’s most extreme endeavors, from mining asteroids to colonizing the ocean, and explain how engineers plan to solve them.

“Twenty years from now you will be more disappointed by the things you didn’t do than by the ones you did. So throw off the bowlines, sail away from the safe harbor, catch the trade winds in your sails. Explore. Dream. Discover.” – Not Mark Twain (regardless of what Virgin Galactic would have you believe).

If you’re going to settle Mars, there are a couple of questions that you have to answer straightaway: 1. Where? 2. How? 3. Who? That third question is especially difficult to answer—building a colony on Mars isn’t like discovering some Polynesian island and building a hut. Mars doesn’t want you there, and will be doing everything it can think of to keep you away. And if you do plan to go there, you shouldn’t expect to come back. You should, in fact, probably expect a confined life of loneliness, misery, disease, and starvation before you eventually descend into madness and death. Jack Torrance is likely the best-case scenario. Personally, my money’s on a colony of Reavers.

But all of that assumes a Martian colony can actually be built. Let’s start with the basic problems associated with moving to Mars.

Weathering the Weather

The average temperature on Earth is 61 degrees Fahrenheit (with wide variations, obviously). The average temperature on Mars is -80 degrees. But here’s the real challenge: A warm summer day on Mars might hit 71, which is pretty nice. Maybe wear jeans and carry along a light jacket. But that same warm summer day will plunge to -100 degrees come nightfall, with 100 percent humidity going into the following morning. (I’m going with’s numbers here.) So even though we have lots of experience (relatively speaking) living at research stations in Antarctica, it’s not exactly a 1:1 comparison. (Average temperature in Antarctica: -34.4 degrees, with no 170-degree swings.) The point is, if you’re building a house on Mars, you need to build one that neither braises nor freezes the Reavers inside.

We should also talk about the weather. The Butterfly Effect aside, when there’s a sandstorm in Dubai, your average New Yorker doesn’t change her dinner plans. Mars is a little different, though, with dust storms that engulf the entire planet. So in addition to moderating temperature, your shelter needs to be pretty durable. When it’s humidity-caked in red dirt, it’s not like you can just find someone on Angie’s List to pressure wash the siding.

And those are only the trivial problems.

The Radiation Problem

In 2001, NASA sent a particle energy spectrometer to Mars to study the red planet’s radiation. This was called the Mars Radiation Environment Experiment, or MARIE. The device found that the surface of Mars has two and half times the radiation that you’d get at the International Space Station, and that’s not even counting the solar proton events, which come without warning and really bombard the place. “Wait a minute,” you say. “Why don’t we worry about solar proton events here on Earth? I mean we share the same sun!” Good question. When the protons of an SPE hit Earth, the magnetosphere pulls them to the poles, and the ionosphere (just below the magnetosphere) handles the rest. This is called polar cap absorption, and is one of the many reasons why Earth is a wonderful place indeed. Mars, lacking a magnetosphere, offers no such protection. How much of a problem is this, human-life-wise? After a series of solar flares in 2003, MARIE was damaged and rendered inoperable. If the sun is frying the machines on Mars designed to measure such solar salvos, imagine what it will do to humans. So, cancer: CHECK.

Power Issues

Even the dust storms are more than an annoyance. See, if we’re going to live on Mars, we’re going to need a reliable source of electricity. Because of the temperatures, lack of natural resources, incompatible atmosphere, etc., life support systems are really, really important. In six words: If the power fails, you die.

There are few more reliable sources of power than the sun, right? (Well, there’s nuclear power, but present political opposition has effectively removed that from the table.) The problem with solar panels is that those planetary dust storms can reduce sunlight by 99 percent. Uh-oh. Suddenly, your greenhouses aren’t growing vegetables and your solar cells aren’t charging very well. Your water-recycling and air filtration and temperature regulation systems are in jeopardy. You’re living off of reserve power and reserve supplies. Better hope the storm ends before the batteries do.

Conquering the Atmosphere

Another thing. Human beings have evolved very nicely for long, comfortable lives on Earth. We developed to enjoy the air, the sun, the land, the microbes, the gravity. We’re biologically equipped to survive a good 70 years on terra firma, and some of us much longer.

Not so much on Mars, though. The Martian atmosphere is thin. Really thin. A guy named George Armstrong did some research and determined that there exists an altitude at which the boiling point of water is 98.6 degrees. You might recognize that temperature as the happy result on a thermometer—unless you’re at the Armstrong Limit. Then it’s a really sad result because your bodily liquids will begin to boil. Tears, saliva, the lining of your lungs, etc. (Your blood is OK, as is your interior water, so to speak. Skin is an excellent protectant.) The atmospheric pressure of Mars is well over the Armstrong Limit. That means you’re confined to the colony. If you want to take a stroll, you’re confined to a space suit. “Well fine,” you say, “I’ll just wear a space suit.”

Getting Around

That’s a smart thing to do. But that suit is also pretty limiting. When you land on Mars, you won’t be climbing mountains and planting very many flags. You’ll have a small radius of travel, and that’s it for the foreseeable future. Are you familiar with the color brown? Because that’s all you’re going to see on Mars. “Well I’ll just saddle up one of those rovers,” you say, “and zip around to see the sights.”

This might not be the most effective means of travel. It’s taken the NASA rover Opportunity a full decade to travel a total of 23.94 miles. In six years, rover Spirit traveled 4.8 miles. Rover Curiosity is expected to travel a minimum of 12 miles. Rover Sojourner traveled 330 feet. None of this is to diminish the extraordinary engineering that was required to build, deploy, and operate the rovers. Those things are nearly indistinguishable from magic and have advanced human knowledge immeasurably. But they also offer a little perspective on what the best of our efforts can do. None of these rovers would have been able to finish a marathon in less than 10 years, if they could finish one at all. So it’s not as though we’ve established a proof of concept for a Martian freeway.

Getting There At All

One more point concerning our frail bodies: Consider that the ride from Earth to Mars takes about six months when the planets are close. At a compounding loss of 1 percent bone density per month, which is what you’re going to get in zero gravity, you’re looking at brittle bones before you even touch the Martian surface. Likewise muscle atrophy. A recent study by NASA found that even our steely-eyed astronauts, disciplined and no strangers to physical fitness on Earth and in space, lost significant calf muscle volume, peak power, and force-velocity characteristics over six-month stays on the International Space Station. We’re talking significant decreases in the 30% range, all around, even while engaging in a pretty serious exercise regimen. Try moving into a new house while you have pneumonia. That’s about what it’s going to feel like when you get to Mars.

Taken together, all of this probably makes temporary human settlement on Mars—let alone permanent colonies—sound impossible. But it’s not. In the next entry we’ll take a look at what engineers have up their sleeves to counter the problems of Martian settlement, and why it really can become a reality.