A Realistic Look At How Humans Can Live On Mars

Author Michael Tennesen takes us on a speculative journey

By Michael Tennesen

The term “sci-fi” generally conjures up thoughts of far-off hypotheticals and surreal narratives. But The Martian, the 10th highest grossing film of 2015, is not some pie-in-the-sky blockbuster for stoners and conspiracy theorists. The next flight to Mars departs today, March 14, at around 1:31 PM, PST from Kazakhstan.

No human passengers will be aboard the European Space Agency’s ExoMars spacecraft, but one of the main goals for this mission is to prepare the agency for future missions to the red planet, including a rover that will land on the surface in 2018 to look for signs of life.

Just six months ago, NASA unveiled a plan entitled Journey to Mars: Pioneering Next Steps in Space Exploration, announcing: “In the next few decades, NASA will take steps toward establishing a sustainable human presence beyond Earth, not just to visit but to stay.”

This Proton rocket will carry the European Space Agency’s ExoMars spacecraft on the first part of its 2016 journey to Mars Courtesy of ESA-Stephane Corvaja, 2016

Interplanetary travel is happening, folks, whether you’re ready to pack up your things for the next shuttle or not. Sure, it’s because humans are a little crazy and think space is cool, but it’s also because of the very real threats we face here on earth with depleting resources, a growing population, and climate change. While, according to a Pew Research poll, only 30 percent of Americans think that climate change will affect them personally, scientists aren’t so confident.

Science Journalist Michael Tennesen spoke with leading experts on Mars resettlement for his new book “The Next Species” (Simon & Schuster) coming out in paperback on March 29. Here’s what they have to say about what we’re gonna need to make this thing happen.

If we spoil the earth, should we try another planet? Interplanetary travel could be a major force for human change. Other planets could have different atmospheres, dissimilar amounts of cosmic radiation, varying periods of night and day, wildly divergent temperatures, and drastically disparate amounts of gravity. All of these are strong evolutionary forces that could over time change man into something quite different from what he is here on Earth. The change in gravity alone could make the difference. In discussions about such travel, Mars is often mentioned.

The fourth planet from the sun is more like Earth than any other body in our solar system. The surface of Mars is more rugged, as it is older and less subject to repair. Mars has dry-ice fields, craters, volcanoes, floodplains, canyons, chasms, and tall mountains. Olympus Mons stands about 16 miles (25 kilometers) above the Martian surface and covers an area 374 miles (624 kilometers) in diameter, about the size of the state of Arizona.

Mars has long attracted the attention of stargazers, since it is often considered the closest place we could run to if life grew inhospitable on Earth. It could also be a jumping-off station to the mineral-rich asteroids that orbit nearby. With its low gravity, Mars might prove to be a springboard to distant stars in our galaxy. Mars Odyssey, in orbit around Mars since 2001, used an infrared camera and a gamma ray spectrometer to map the content of the Martian surface, finding large regions near the poles where the soil had over 60 percent water ice by weight.

The Dutch nonprofit Mars One plans to establish a human colony on the red planet in or shortly after 2023

Scientists believe these watery observations are proof that Mars once had a warm, wet atmosphere that was suitable for life. Early Mars had a lot more CO2 in its atmosphere than it does today, and that produced a considerable greenhouse gas effect and a much milder climate. These conditions persisted on Mars about four billion years ago, close to the point where life evolved on Earth. Could life have evolved on Mars about the same time? Is life on other planets a possibility? With so many millions of stars and millions of planets around them, how could we be the only one?

A recent exploration by the Curiosity rover in 2013 analyzed a powdered sample of soil and found some promise. Only a half mile from the landing spot in the middle of the three-mile-high Gale Crater, Curiosity sampled a rock that contained sulfur, nitrogen, hydrogen, oxygen, phosphorus, and carbon — a sampling of the major ingredients of life on planet Earth.

In 2011 the Mars Reconnaissance Orbiter found seasonal streaks that formed and disappeared on a Martian slope and may have been the result of underground water ice that thawed and flowed in the Martian spring. Much of Mars’s water is held in permafrost soils or ice. Robert Zubrin, author (with Richard Wagner) of “The Case for Mars: The Plan to Settle the Red Planet and Why We Must,” says, “Current knowledge indicates that if Mars were smooth and all its ice and permafrost melted into liquid water, the entire planet would be covered with an ocean over 100 meters deep.”

“Daytime temperatures on Mars can get up to 63 degrees Fahrenheit, but at night they dive down to minus 130 degrees” — Michael Tennesen

Mars may once have had a warm and wet climate suitable for the origins of life. In their first billion years or so, both Mars and Earth had carbon dioxide atmospheres and were covered with water.

We know that life evolved on our planet, but did it evolve on Mars? Is life a million-to-one long shot that could hardly occur anywhere else, or is it a natural occurrence of certain environmental conditions? If we found living organisms or simple fossils on Mars, it might mean that the universe is full of life. And that would be big indeed. It could perhaps be the escape hatch for man.

The greatest hurdle to the continued exploration and space station development on Mars is, like many things, money. Where does one get enough? When John F. Kennedy launched the Apollo program, which sent men to the moon, the US and Russia were in the middle of the Cold War, and competition and national pride were behind the big push to the moon. But the Cold War days are gone, and nothing like that has arisen to move the Mars program forward. Some say we should wait for technology to advance, to reinvent itself, but Zubrin says time is a-wasting. He feels we can get to Mars with what we’ve got: technologies based on Saturn V rockets from the Apollo days with engines and boosters developed during the space shuttle era.

Mars is a bit out there. At its closest orbital position, it is around 38 million miles (56 million kilometers) distant. The best time to launch a trip from Earth to Mars would be when the planets are at their maximum distance. Over the long trip, eventually the two planets would come closer together, and the trip would then be made over the smallest distance.

Then there’s the problem of gas. Zubrin feels that it’s too difficult to go to Mars and return home with enough gas to make the round trip. One of his most daring proposals is that we get our fuel not from Earth but from Mars. He believes that we need only carbon and oxygen from Mars and a little bit of hydrogen (about 5 percent) that we could bring from Earth. Carbon dioxide could be pulled straight out of the Martian air, which is 95 percent CO2. Take a jar and fill it with activated carbon or other suitable material and set it out in the super-cold Mars night. With a nighttime chill of minus 130 degrees Fahrenheit (minus 90 degrees Celsius), the material will soak up 20 percent of its weight in CO2. When the sun comes back up, the material will warm up and we will generate high-carbon gas.

The idea is to send the unmanned apparatus to Mars, let it process the fuel first, and then send the manned mission when the gas station is full and in place. The first missions might have enough gas to go both ways, but the extra weight would require additional thrust, and if we can make rocket fuel from Martian air, we’ll be way ahead of the game.

Once we got enough CO2, we could mix it with the hydrogen we brought from Earth and get methane and water from the combination. The water produced can be split into oxygen, which could be stored, and hydrogen, which could be recycled back into the methane-producing process. The equipment necessary for methane production would comprise three reactors, each three feet (one meter) long and five inches (twelve centimeters) in diameter.

Scientists think that the first missions could be dangerous, and Zubrin agrees but thinks that a small crew would still be best. It would include two mechanics — or flight engineers, if you will — a biologist, and a geologist, four people in all. That would provide two scientist/mechanic teams, one at the base camp and one out in the field. The geologist would explore the planet’s geological history while evaluating the planet’s fuel and geological resources. The biologist could address the question of life on Mars while evaluating the soil and the environment for their ability to support greenhouse agriculture.

We could make plastics out of hydrogen and CO2. Mars soil is full of clay, so we could make great ceramics for pottery, including pots, dishes, and cups, as well as bricks. One of the most accessible materials on Mars would be iron. It is this ore in the soil that gives Mars its reddish color. Carbon, manganese, phosphorus, and silicon are common and could be mixed with iron to make steel. Mars also has a lot of aluminum.

Silicon is plentiful, too. This could be used to make photovoltaic panels, which could generate power, though getting enough will be a problem in the early years. Though probably not a popular idea, Zubrin thinks it would be necessary to import a nuclear reactor from Earth to meet the energy demands of the base’s earlier years. Once the base is well established, solar, wind, or geothermal power could be added to the mix. But nuclear power would be necessary to get things going.

Mars has other precious materials, including deuterium, the heavy isotope of hydrogen, a key element of nuclear power. There is about five times as much deuterium on Mars as there is on Earth, and a kilo of deuterium is worth about $10,000.

But perhaps the biggest attraction to building a station is the possibility of interplanetary trade. Mars is close to the main asteroid belt that circles the sun between Mars and Jupiter. Asteroids contain large amounts of high-grade metal ore, making them attractive for commerce. An average asteroid about one kilometer in diameter could hold about 200 million metric tons (10 percent larger than a US ton) of iron, 30 million metric tons of nickel, 1.5 million metric tons of cobalt, and 7,500 metric tons of platinum, worth about $150 billion for the platinum alone.

A Mars station could be a staging ground for travel to other places in the solar system and beyond. Under Zubrin’s plan, the modules that house the Earth-to-Mars portion of the trip could be repurposed as the first houses of a new Martian settlement. Bricks fashioned from the finely ground, claylike dust that covers the surface of the planet could be used for additional support. These modules could be used to construct Roman-style vaults or large atriums.

The Martian inhabitants would need at least eight feet of dirt on top of their houses to properly pressurize them and to protect their inhabitants from the wide swings in temperature

Houses would have to be built underground. The Martian inhabitants would need at least 8 feet (2.5 meters) of dirt on top of their houses to properly pressurize them and to protect their inhabitants from the wide swings in temperature. Large plastic inflatable structures could be used as temporary housing while underground structures and aboveground greenhouses are being built for eventual crop growth.

Mars’s atmosphere is sufficiently dense to protect its initial builders and farmers from solar flares, and there are other beneficial qualities as well. Martian sunlight, though less than that on Earth, is enough for photosynthesis. Add some CO2 to your greenhouse and that could make up for the diminished sunlight. Martian soil is richer than that on Earth. It may need extra nitrogen, but that can be synthesized as it is here. Raising cattle, sheep, and goats would be inefficient, since it would take five times as much grain to feed the cattle as it takes to feed humans directly, so Mars astronauts might have to forgo steak in the early years.

The first Martian task would be to find water. Evidence from past missions says it’s there. For manned missions, it might work to bring some more of the hydrogen (H) component from Earth to make H2O, but once the building phase ensues and the Mars population begins to grow, water would have to take precedence. A geothermal source with water would be great. Let’s just hope it’s not too close to the poles. Observations by the Mars Reconnaissance Orbiter in 2009 reported pure water ice in relatively new craters located between 43 and 56 degrees north latitude, and that is an area of relatively temperate Martian climate.

On the positive side, if we can overcome these hazards, then a Mars station might offer a place where Homo sapiens can truly differentiate — becoming a new species. Carol Stoker, a planetary scientist at NASA’s Ames Research Center, envisions a permanent research base of closed environments on Mars as the next most logical place to live outside of Earth. Still, she claims a child who grew up on the Red Planet, with one-third the gravity of Earth, would never have the physical or skeletal structure to survive on our Blue Planet.

“It is likely that a second-generation Martian would be physically unfit to walk unaided on Earth, at least without intense weight and strength training,” says Stoker. “Just imagine if you suddenly weighed three times what you weigh now. Could you walk? Would your deconditioned heart be able to pump the blood volume needed? Whether we know it or not, we are constantly doing a lot of work against gravity.”

The European Space Agency, the National Space Biomedical Research Institute (in Houston, Texas), and the Russian Federal Space Agency recently completed a 520-day experiment locking six “marsonauts” in a simulated spaceship near Moscow. Five hundred and twenty days is about what it would take for a round-trip flight to Mars, with about thirty days to explore the surface. During the entire simulation, the crew went without sunlight, fresh air, or fresh food.

The Mars-500 crew hangs out in their fake spaceship in Moscow / Courtesy of ESA

The big thing, however, was the effect to bodily organs, particularly the cardiovascular system. While in space, the body no longer feels the downward pull of gravity that distributes the blood and body fluids to the lower extremities. Fluids start to accumulate in the upper body, away from the legs and feet. In space, astronauts actually start to look different as their faces puff out from the additional fluid in their upper bodies. They develop bird legs as the circumference of their legs shrinks due to decreased fluid in the lower body.

Gravity wouldn’t be the only selective force. Others would include breathing compressed air and adjusting to different loads of UV radiation. The need to eat, go to the bathroom, have sex, give birth — all these vital functions would be seriously altered by changes in gravity, air, and radiation. Living on Mars could produce long-term biological changes that would make a return to Earth ultimately impossible. With isolation a natural part of the job, the gradual push of evolution toward becoming another species could happen in outer space just as well as here on Earth.

Though the sum total of Zubrin’s suggestions may sound daunting, the technological hurdles we’ve surmounted in just the last century make anything seem possible.

Michael Tennesen is a science writer who has written more than three hundred stories in Discover, Scientific American, and New Scientist, among others. His book “The Next Species: The Future of Evolution in the Afterman of Man” will be available for purchase in paperback on March 29.