Let’s Go to Mars. Let’s Not Live There

Space agencies and companies aim to send people to the Red Planet. But settling there would be hell on—well, you know what we mean.

The moon, which seemed so far away for so long, is rapidly becoming the new hotspot for space activities. Following the successful launch of the Artemis program in November, NASA is now looking ahead to moon landings and a lunar space station. China’s space agency aims to deploy lunar landers and rovers and to build a research station on the moon. Companies in the US and Japan have plans in the works for their own moon landers too.

But in the long term, all eyes are on Mars.

NASA chief Bill Nelson considers Artemis to be a stepping stone, part of the Moon to Mars program. The European Space Agency, a longtime NASA partner, has its own Terrae Novae 2030+ program, which is also aimed at eventually sending crewed missions. China’s space agency is at work on landers, rovers, and orbiters. And of course, SpaceX CEO Elon Musk can’t stop talking about how he wants to build Starships that, like “Noah’s arks,” will make humanity a “multiplanetary species,” including building sprawling civilizations on the Red Planet.

But the hellish conditions on Mars make it hard to imagine living there, let alone sending millions. The Red Planet lies on the edge of our solar system’s habitable—or “Goldilocks”—zone, where it’s not too hot or cold to have liquid water on the surface, which is probably necessary for life as we know it. More than 3 billion years ago, Mars was likely much more life-friendly, with some flowing rivers and lakes, a more temperate climate, and a more substantial atmosphere. But today, the thin air is almost entirely made up of carbon dioxide. The temperatures are as cold as Antarctica. It’s many times drier than the Atacama Desert in Chile, the driest place on Earth. 

The first astronauts to travel to Mars, perhaps in the 2040s, will need to cope with a nine-month journey cooped up in a tiny spacecraft. Then they’ll need to survive the landing. If they get that far, life on Mars will be harsh. Frequent sandstorms can bury key equipment or solar panels. There’s no soil for growing food, so they’ll have to rely on whatever they brought with them. A hole in one’s spacesuit would mean certain death. Any significant problem on base—like a loss of power, oxygen, water, food or communication with Earth—would probably doom the whole crew. If something goes awry, they’ll be on their own. While the moon is nearly 1,000 times as far away from Earth as the International Space Station and the Tiangong space station, Mars is hundreds of times more distant than that.

The isolation of the Covid pandemic might give us a small taste of the psychological challenges of life on Mars. Those first visitors will be trapped in one or two small structures with the same few people for something like 2.5 years, counting travel each way and around a year on the ground. Just going for a walk outside would be a huge ordeal. They would never see a single tree in any direction, never dip their feet in a river, nor fill their lungs with fresh air in the morning. Everyone will have a good chance of getting cancer (thanks to a high dose of space radiation) or losing bone and muscle mass (thanks to the long flights and the planet’s weaker gravity). 

So why would anyone even want to go?

Well, there aren’t that many other options for the intrepid space traveler. Despite its many challenges, after the moon, Mars seems like the obvious next stop for exploring the solar system. It’s more hospitable than greenhouse-smogged, excessively hot, high-pressure Venus. It’s much closer than asteroid belt inhabitants like Ceres and Vesta. The moons of the gas giant planets, like Europa, Enceladus and Titan, look intriguing, but they’re so distant that Earthlings probably won’t be able to visit them until the 22nd century. Mars, to its credit, has ice that could be used by astronauts, and it’s close enough to the sun for a colony to generate solar power. 

For years, space agencies have been exploring it with robots, like NASA’s Perseverance rover, the Maven orbiter, and the InSight lander. Even more are lined up, including China’s Zhurong rover and Tianwen-1 lander, Europe’s Rosalind Franklin rover, previously known as ExoMars, and NASA’s sample return mission that will pick up the rocks Perseverance collected. But there’s only so much the agencies can study from afar.

To really advance scientific discoveries, learn more about the Red Planet’s climatic and geological evolution, and unpack the history of our solar system, they think they’ll have to send small crews. The first human visitors might just orbit and map the surface, studying its ancient geology while looking for possible landing spots—the same function the astronauts aboard the 1968 Apollo 8 mission and the Artemis 2 mission planned for 2024 serve for moon exploration. Later on-the-ground crews might uncover crucial details about the origins of life, and maybe even evidence of never-before-seen life-forms. 

That’s a powerful motivator: To learn about humanity’s role in the vast cosmos. Humans have always explored, and we want to know what’s out there—and who’s out there. “One of the best things about us as a species is our curiosity and our desire to know how we are part of the universe. I think that that larger perspective is very valuable,” says Sasha Sagan, daughter of science communicators Carl Sagan and Ann Druyan and author of the book For Small Creatures Such as We.

What vision of Mars exploration will humanity realize? Wernher von Braun, America’s first real celebrity space figure, envisioned launching spacecraft to the moon and Mars, a vision we’re still following today. But in his view, these would be military-led expeditions, establishing dominance on other worlds while looking for military applications for new resources and technologies. After leaving Nazi Germany in 1945, von Braun led NASA’s development of the powerful Saturn V rocket used in the space race with the Soviet Union.

Carl Sagan, the author of Cosmos and Contact, was arguably the US’s next major space leader—with his more hopeful, peaceful, and science-focused perspective. While he wasn’t against crewed spaceflights, he generally advocated for sending robotic probes to learn more about our cosmic neighborhood as a less risky and more efficient use of resources. Sagan contributed to the Pioneer and Voyager programs, and played a major role in the Voyager Golden Records. 

Today, that celebrity role largely belongs to billionaires with more apocalyptic visions, who are raring to quickly send huge populations off-world, citing fears that Earth could be destroyed or become uninhabitable. “The new von Braun is of course Elon Musk,” says Jordan Bimm, a University of Chicago space historian. “He presents himself as a potential ruler of a Mars society.” The SpaceX CEO has referred to the sun’s eventual death, and to killer asteroids on collision courses, as motivators to build a civilization on Mars, even though such events happen on geological and cosmic timescales, not human ones.

He isn’t the only one. Billionaire Jared Isaacman, who bought seats on the Inspiration4 spaceflight last year, has made similar comments. So has Blue Origin CEO Jeff Bezos. And so have a few top aerospace executives, including SpaceX president Gwynne Shotwell and Tory Bruno, CEO of the United Launch Alliance, a Boeing and Lockheed Martin joint venture. While Musk has proposed somehow sending a million people to Mars by the year 2050, Bruno proposed dispatching a few score for short visits, setting the stage for colonies in the next century, when self-sustaining technologies advance and trips become cheaper. Meanwhile, Bezos dreams of billions of people living in orbit around the Earth, while treating our world like an unpopulated national park.

But so far, none of these commercial space companies are anywhere close to realizing these audacious visions. SpaceX has flown taxi and cargo rides to the ISS for NASA and the private company Axiom Space, but otherwise it has only flown a single crewed spaceflight in low Earth orbit, Inspiration4. SpaceX has invested heavily in the Starship spacecraft and Super Heavy Rocket, which are currently undergoing fueling and rocket engine tests; they are planning an uncrewed orbital test launch in early 2023. NASA has tapped SpaceX to provide a modified Starship for the Artemis 3 and 4 moon-landing missions, but those won’t happen until later this decade. 

Blue Origin, for its part, has only launched a handful of suborbital spaceflights that briefly flit along the edge of space. The first flight of the company’s massive, reusable New Glenn rocket, which could send crews and cargo into orbit, has been delayed for years, with its launch now planned for late 2023. Boeing’s Starliner, a potential SpaceX competitor for NASA’s commercial crew program to the ISS, has been delayed as well, with the first crewed flight scheduled for April 2023. While these companies have made significant accomplishments, they’re far behind the out-of-this world comments made by some CEOs.

Such off-world ventures can also seem hard to justify when we Earthlings are plagued by climate change, pandemics, risks of nuclear war, and rampant inequality. Setting up a research station and living quarters for a half dozen visitors—as space agencies might eventually do—would likely cost tens of billions of dollars. (If Musk really intends to send thousands of Starships to Mars, that’s more like a trillion.) 

Some people would rather invest these resources in solving global problems, not launching astronauts to other worlds. People in the 1960s questioned the Apollo program for similar reasons—it was also a time of systemic inequality and fears of nuclear war. Today, in public opinion surveys of US adults, NASA’s climate-related efforts and monitoring of near-Earth asteroids are more popular than crewed missions to the moon and Mars. 

“It would be easier to justify going to the moon and then Mars if people weren’t starving and dying. I don’t think there’s a scientific rational reason for it, and that’s OK,” says Natalie Treviño, a space theoretician at the Open University in the UK. Yet as she points out, the drive to explore isn’t always logical. “Why do we make art and make music? Living in contradiction is what the human experience is. It’s both amazing and tragic.”

Depending on the animating vision behind Mars exploration, the first astronauts could be scientists, poets, tourists, or military officers. They could be viewed as visitors, settlers, cowboys, or colonists. Treviño prefers the term “migrants”—partly to destigmatize migration on Earth—and she favors including an artist to make sense of the existential experience, and enormous culture shock, of living on this ruddy, barren world.

Let’s say it works: Humanity overcomes the cost and practical barriers of settling Mars, and the migrant Earthlings arrive. There’s one thing left to consider: Maybe Mars would be better off without us.

If our treatment of Earth’s atmosphere is any sign, we’ll corrupt the Martian one too. We’ll litter it with junk, as we have despoiled our own world. Maybe we’d geoengineer the atmosphere, or live out Musk’s desire to terraform the world by blowing up nukes to create a “nuclear winter”—something we’ve managed to avoid so far at home—to raise temperatures, initiate a helpful climate change, and melt some of its polar ice. As with geoengineering proposals meant to combat climate change on Earth, such schemes carry huge risks.

We’d also mine the surface, likely reproducing the economic inequalities and unsustainable practices already prevalent on Earth. For example, Treviño says, there’s a limited supply of Martian ice, but no binding rules exist saying who could use it, how much, and for what purpose. Plus, if any Martian life-form lies underground, terraforming and mining attempts may well destroy them and their ecosystem, and who are we to decide their fate? It’s the height of hubris for one species to decide what should be done with an entire planet that’s not their homeworld. 

So as we venture toward Mars, let’s be ambitious and curious, but also thoughtful, ethical, and sustainable. Our travels many millions of miles away will likely serve to remind us how lucky we are to have our own world, says Sasha Sagan: “I suspect that the further we go, the more we’ll realize how precious and valuable this one planet is.”

Let’s Go to Mars. Let’s Not Live There

(May require free registration to view)