Elon Musk’s Mars illusion

Ever since its founding, SpaceX has fixed upon a single idea: Elon Musk’s vision of colonizing Mars. Everything the company does is geared to that foundational goal.

Two years ago, Musk posted on X that there could be a city on Mars within 20 years, “but for sure in 30.”

“Civilization secured,” he added, implying that even if our troubled lives here on Earth come to some catastrophic end in the coming decades, don’t worry, humans will endure on Mars.

Musk’s initial steps toward this ambition have produced awesome engineering successes. People have never seen the likes of the light displays that shower across night skies from SpaceX’s rockets and satellites. They watched astounded in late 2024 when the gigantic Starship’s booster rocket first descended gently to nestle into enclosing mechanical arms at the launch site in Texas.

Yet the work of scientists studying Mars suggests that it’s far-fetched, perhaps delusional, to think a human colony could be established there. You don’t need to be a billionaire or a rocket scientist to realize Musk’s timeframe is certainly a fantasy; there won’t be a city on Mars in his lifetime or that of his children or his grandchildren. Think many, many decades at best. But more likely, never.

Retail investors rushed to buy SpaceX stock after the IPO in June. Though the share price has already fallen back below where it was that day, many see it as a long-term investment. The reality is that the improbability of the Mars project shadows SpaceX’s long-term future.

While humans will at some point likely overcome the massively daunting engineering and logistics challenges of getting to Mars and even staying for some time, there’s no technology available to form a permanent settlement there.

Musk may be excused as being playful with his time scale.

“Oh, Elon is famously bad at giving time estimates,” said Erika DeBenedictis, a biological engineer and Mars scientist, founder of Pioneer Labs, which is researching how to grow plants on Mars. “Things always take longer than he says, but they do tend to happen.”

Musk has been quite specific. Last year, he said SpaceX had a 50:50 chance of sending its first uncrewed Starships toward Mars in 2026, with crewed landings to follow “as soon as 2029, although 2031 is more likely,” he posted on X.  

Then, this February, he said SpaceX would build a city on the moon first and start building a Mars city “in about 5 to 7 years.”

While his targets and timing keep moving, the problems go deeper than that. The question is not when humanity will expand beyond Earth, but whether it ever will.

Establishing a city on Mars depends crucially on a concept called “terraforming,” which means physically transforming the planet’s surface environment into something resembling that of Earth, at least partially hospitable for humans.

To DeBenedictis, the sterile science fiction notion of people confined inside glass domes, looking out upon a forbiddingly bleak landscape and living off protein shakes and dried food, is deeply unappealing. “I wouldn’t want it and I wouldn’t want it for my daughter,” she said. “It just seems terrible.”

“It doesn’t have to be that way,” she adds. “I want the planet to be green.”

DeBenedictis concedes at the outset of an interview that this is “probably impossible,” though in the tone of someone who lives to chase the impossible.

In contrast, Musk glibly mentions terraforming as if it were within reach. In truth, science has only highly conjectural ideas about how it might be done. The hypothetical options scientists are researching now, if they work at all, will take many decades if not centuries to make Mars habitable. And they may never work.

A titanic ambition

Despite this, investment bankers and those with pre-IPO access were primed to ride the coattails of Musk’s colossal wealth for a big payout on SpaceX’s Wall Street launch day. Musk supercharged the June IPO by absorbing his xAI project into SpaceX. The IPO filing positioned xAI as a $26.5 trillion market opportunity, dwarfing all the other business segments of SpaceX, which the filing pegged at a mere $2 trillion. What’s an IPO without a transcendent AI promise these days?

The controversies around Musk’s politics and conduct — his embrace of President Trump and other authoritarian leaders, his incendiary rhetoric, his reposting on his X platform of right-wing influencers agitating around immigration and race, his eager wielding of a chainsaw to U.S. government services — were set aside by investors as they scrambled to buy in.

Wall Street weighed only Musk’s entrepreneurial success and his ability to conjure the future and spin financial dreams. The Economist in May called Musk’s risk-taking and mobilizing of resources “capitalism at its most remarkable.”

For Wall Street, that made the SpaceX IPO a surefire winner. The share price duly rocketed up and made Musk briefly a trillionaire. Though he lost that status when the share price subsequently slid, he’s still by far the richest man in the world with a net worth into the $900 billions.

That fortune is built upon the market perception that Musk can turn dreams into reality. Mass-producing all-electric, virtually self-driving cars was once a pipedream. Rockets landing on their tails graced the covers of 1950s science fiction novels. By force of will, Musk made both a reality. Whatever pipe he’s smoking now, shouldn’t we give his Mars dream some healthy respect?

That dream is specified precisely on the SpaceX website: “A permanent human colony on Mars with at least one million inhabitants.”

Musk designed the huge Starship rocket to go to Mars. And when Musk first unveiled his plan for the internet satellite venture that became Starlink in Seattle more than a decade ago — the satellites are made in Redmond — he told Bloomberg Businessweek he saw it as “a long-term revenue source for SpaceX to be able to fund a city on Mars.”

Nearer term, SpaceX is to provide the lunar lander for NASA’s Artemis project that should return humans to the moon within a few years and lay the groundwork for a permanent moonbase; Musk sees it as a stepping stone to the true goal.

The problem is, Mars is not even remotely habitable. It’s deathly cold. There’s nothing on the surface but dust and rocks, in places some deeply frozen CO₂. Regular dust storms whip the surface. The planet has zero vegetation; not a tree, not a leaf, not a blade of grass. The oxygen-free Martian air is unbreathable.

Venture outside without a space suit and you’ll die within a minute in the poisonous, low-pressure atmosphere. During unpredictable solar flares, cosmic radiation is a separate threat to life.

Martian gravity, one-third of Earth’s, may deform the human body over time. Astronauts on the zero-gravity International Space Station must work out constantly to retain muscle strength. Even then, if they spend too long in space they must be carried from the space capsule after splashdown.

“I don’t see any prospect for there to be permanent settlements,” said senior NASA astrogeophysicist Chris McKay, who for more than 40 years has studied the possibility of supporting human life beyond Earth, and on Mars specifically. “Why would anybody want to live there?”

Bruce Jakosky, professor emeritus at the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, who has studied Mars his entire career since he worked on the Mars rover Viking mission in the mid-1970s, says he thinks it will happen someday, but adds, “I have no idea when or how.”

“It’s far enough into the future that, once you get beyond, say, 30 years, you can’t tell the difference between that and infinity into the future,” Jakosky said.

That’s scientific realism. Buzz Lightyear talks about getting to infinity and beyond, but he’s a toy.

What’s really achievable on Mars

Despite the cold facts, Musk has so successfully sold the notion that if he put out a call for volunteers for the first Starship mission to Mars, hundreds of space scientists, enthusiasts, adventurers and Musk fanbros would eagerly sign up.

Indeed, he already has a Mars mission volunteer. On the launch webcast of SpaceX’s latest and largest Starship rocket in late May, a presenter introduced cryptocurrency billionaire and civilian astronaut Chun Wang, revealing that he’s been tapped to lead the first crewed flyby mission to Mars at some unspecified future date — a round trip of about two years, going there and back without landing on the surface.

And yes, it’s inevitable humans will get to Mars one day. Crewed spacecraft may land on Mars within a couple of decades.

The first astronauts to land will plan to explore the surface and hopefully return in triumph two years later, the next occasion when the Mars solar orbit again aligns with Earth. DeBenedictis dismissively describes this as the “expensive camping trip” phase of exploration, “mostly for the photo opp.”

Decades from now, humans may take a much harder, more substantive step: establishing a scientific base on Mars; we have such bases in Antarctica today. Researchers could rotate in and out every couple of years.

Creating a permanent colony on Mars is something far different. It implies lifetime commitments and subsequent generations growing up and building their lives there. As Elton John sang, “Mars ain’t the kind of place to raise your kids. In fact, it’s cold as hell. And there’s no one there to raise them if you did.”

A child born on Mars — a Martian! — would likely adapt to the low gravity as it developed. We have zero data on the physical consequences. Such a child could grow up so different in muscular and skeletal strength that he or she would be unable to walk on Earth.

“The first mothers that give birth will be guinea pigs,” said NASA’s McKay.

And yet, Musk has laid out a plan he insists can establish a human colony on Mars within his lifetime. After Optimus humanoid robots designed by Tesla do some advance exploring on the Martian surface, eventually “a few thousand” Starship rockets will head off together from Earth orbit to Mars, loaded with people and more than a million tons of equipment, dried food and supplies.

The SpaceX website offers a few images envisioning life in the early days of a Mars colony. A mom and two kids look out from inside a glass dome as a Starship lands nearby. The accompanying text on the website glances over some of the most glaring problems.

The extreme temperature fluctuations, from 70°F to -225°F, with an average of about -85°F? “It is a little cold, but we can warm it up.”

The atmosphere of mostly unbreathable CO₂? That’s good for plants; those don’t need oxygen. “We can grow plants on Mars just by compressing the atmosphere.”

That one-third gravity compared to Earth? “You would be able to lift heavy things and bound around.”

In a speech a year ago to employees at the Texas rocket site — the video is on the SpaceX website — Musk conceded that Mars is inhospitable but said terraforming will provide the solution.

“You can’t really walk around on the surface of Mars, at least as yet until Mars is terraformed to be like Earth,” Musk told the employees. “You need to walk around with a Mars suit and be initially in kind of like glass domes.”

“But it would work,” he added. “And eventually we can make Mars into an Earthlike planet.”

Yes. Terraforming. How exactly could that be achieved? And how long would it take?

The science on terraforming

SpaceX did not respond to requests to grant an interview or to offer comment on the feasibility of Musk’s vision. But Mars scientists have studied the question. Edwin Kite, associate professor of planetary science at the University of Chicago, resident at the Berkeley-Calif.-based Astera Institute that funds futuristic science, is a leading researcher on terraforming Mars. In a paper published in April in collaboration with two dozen other Mars scientists, including DeBenedictis, he assessed the feasibility of the potential pathways currently being studied.

His paper begins with a bracing caveat: “It is unknown whether human civilization can thrive off-Earth.”

But if we want to try living on Mars, the paper says, the first requirement will be to warm the freezing planet or at least regions of the planet. It lays out three possible ways to do so.

Some local regions on Mars could hypothetically be warmed by spreading a translucent, high-tech blanket that would block harmful UV radiation but otherwise allow sunlight through to warm the Martian soil. The solar warmth trapped beneath the blanket, made from a plastic-like biomaterial, would melt ice under the ground. The heat and water would then potentially support primitive life forms, starting with microbes, bacteria and algae and, in time, plants.

However, even warmed, wet Martian soil is salty and laden with bleach-like chemicals hostile to life. No known micro-organism on Earth can survive in such conditions.

That’s where DeBenedictis’s research comes in. Her team — funded in large part by crypto billionaire and space entrepreneur Jed McCaleb, who founded the Astera Institute — is trying through selective breeding and genome modification to engineer new, hardier biological organisms that could get life started in the Martian soil. She is looking to microbes that could digest the bleach and others that could produce more of the bioplastic, allowing extension of the soil-heating blanket to a larger area.

The idea: as the soil improves with this microbial organic matter, more complex organisms could take hold. Eventually, she says, “you could actually do things like grow potatoes in the dirt.”

DeBenedictis is super optimistic about biology turning Mars green. It could have a cover of basic plants “in my lifetime,” she says.

Pioneer Labs has been going for just two years. Its early-stage research is developing lab-grown microbes inside enclosed, stirred, heated, radiation-shielded vessels, like high-tech Instant Pots. It’s a long way from growing potatoes.

DeBenedictis notes that although the lack of oxygen means humans still couldn’t breathe outside, plants grown under these bioplastic blankets would produce oxygen through photosynthesis. That might eventually build up a breathable atmosphere on Mars at some point in the far future. Kite said the timeframe for that would be centuries, at least — “much longer than your civilization-relevant time scales.”

The second warming method outlined in Kite’s paper: large reflecting mirrors in orbit around Mars, beaming down sunlight to warm a contained scientific base and the region immediately around it. The first reflectors would launch from Earth as solar sails, unfurling in space and flying themselves to Mars, propelled by sunlight.

Kite projects that doubling the sunlight reaching an area of less than half a square mile on Mars would require a large constellation of reflectors in sun-synchronous orbit, with a combined surface of nearly 300 square miles.

That’s a huge armada of solar sails heading off to Mars, all of which would have to be managed and maintained from Earth.

The third and most extravagant pathway being studied: warm the entire planet by forcing artificial global warming.

At one time, it was hoped that local warming on Mars would release frozen CO₂ in the ground as a greenhouse gas that would thicken the atmosphere and gradually warm the whole planet, the same process now warming Earth. But a 2018 paper by Jakosky dashed that plan. Analysis of sensor data and imagery from the latest satellites orbiting Mars showed there’s not enough frozen CO₂ on the surface to provide significant greenhouse warming.

That paper concluded that “terraforming Mars is not possible using present-day technology.” Embed from Getty Images

To overcome that setback, scientists developed a new idea: pumping a few million tons of aerosol particles into the atmosphere, artificial dust manufactured on Mars from material in the soil. These clouds of dust, which would very slowly settle and have to be continuously spewed out, would warm Mars by trapping the solar heat.

But the time scale for this is the longest under consideration. NASA’s McKay, in a 1991 paper, analyzed the timeframe for a greenhouse effect on Mars, based on how much of the solar energy reaching its surface might be realistically trapped. He calculated that it would take 100 years to warm the surface to an Earth-like temperature, and “perhaps 100,000 years” to eventually produce an oxygen-rich atmosphere from plant photosynthesis.

Kite, in an interview, said it would take “decades, at least” just to build the robotically-operated factories on the Martian surface that would manufacture and disperse the aerosols across the planet. His paper projects the cost of the aerosol project at $1 trillion.

DeBenedictis said this enormous investment and the extended time scale of planetwide warming make the more local methods the only practical options.

Yet even if any of these planet-warming methods work, that still leaves the other major problems. While machines can extract oxygen from the CO₂ in the atmosphere and pump it into sealed indoor living spaces, the air remains unbreathable outside. The extremely low pressure and potentially deadly cosmic rays remain unaddressed. Inside and out, the low gravity will still, over time, exert its unpredictable physical impact on human bodies.

In short, even if these wildly speculative, generations-long projects succeed somewhat in warming Mars, the result will fall disappointingly short of Earth-like. Dreams of colonizing Mars could still reach a dead end.

Concluding his summary of the various possible paths toward terraforming Mars, Kite notes that “no approach has been shown to be simultaneously affordable, safe, scalable, and to enable extending life beyond Earth.”

As one might expect from a group of Mars researchers, Kite’s paper urges that terraforming research continue, arguing that “a finding that no approach is viable” would at least curtail the vast expense and bring more realism to plans for large numbers of people to self-sustain anywhere beyond Earth.

SpaceX woos investors

SpaceX’s IPO prospectus relegated such downer conclusions to the “risk factors” section that offers legal cover in any such financial filing. The Mars mission and similar space endeavors, the filing said, “involve significant technical complexity, unproven technologies, or technologies that do not exist or may require significant advancement.”

Outside that CYA boilerplate, the prospectus offered investors a Musk-style sprinkling of high-flown stardust. The SpaceX “mission is to build the systems and technologies necessary to make life multiplanetary, to understand the true nature of the universe, and to extend the light of consciousness to the stars.”

In case that was insufficiently inspiring, the prospectus added a dash of fear, stating that humanity needs to spread beyond Earth to survive a potential planetary catastrophe. “We do not want humans to have the same fate as dinosaurs,” it stated.

When Musk addressed employees in Texas as the IPO opened trading on June 12, he gushed enthusiasm for his vision: “There have to be things that make you excited about the future, that make you glad to wake up in the morning because you can’t wait to see what happens next.”

The risk to future funding

For Musk, maintaining such enthusiasm will be essential. For beyond the scientific and engineering challenges of the Mars enterprise, politics and economics could be showstoppers.

After the inspiration of the first human moon landing in 1969, the public quickly lost interest in subsequent Apollo missions. However scientifically interesting, the moon seemed to offer little but dust and rocks.

SpaceX’s stunning rocket launches and the recent Artemis mission that swung astronauts around the moon have reignited space travel enthusiasm in a new generation.

But interest could collapse again.

Kite’s paper notes that “If in the future crew were lost and there were no obvious short-term financial benefits to exploration, society might cease to pay the high costs of sending people to space.”

Orbiting space satellites — chiefly communications, navigation, imagery, surveillance, and missile detection — will continue to rake in cash for SpaceX, much of it from the government. And Musk is well-placed to grab lucrative Pentagon contracts to deploy weapons to kill enemy satellites and defenses to protect ours.

And leveraging the hot-buzz AI trend, SpaceX now plans to build satellites that will act as solar-powered AI data centers in space. The value of this is uncertain; why pay the enormous costs to put data computers into orbit when you can run them on Earth? Still, it seems less of a pipedream than a city on Mars.

But crewed space missions beyond Earth orbit produce no immediate applications. An investment sinkhole, they demand clear-eyed purpose, not delusion.

In an interview, Jakosky — who like McKay, Kite and DeBenedictis fervently wants humans to be interplanetary one day — said he doesn’t buy Musk’s idea that if, say, climate change makes Earth less habitable, Mars can be a “back-up planet.”

Terraforming Mars is just too far out, he believes.

“It’s an incredible amount of money and resources that would be better spent understanding our own climate here,” Jakosky said. “It’s always going to be easier to terraform the Earth, bring it back to the current conditions, than it is going to be to terraform Mars.”

The realistic future

If the Mars project fades in the years ahead, Musk may try pivoting entirely to AI as the new vision — and investment draw — for SpaceX.

In the meantime, the next big technical milestone, one needed just to reach the moon, never mind Mars, will be refueling rockets in space. If this and other hard-to-pull-off engineering challenges can be met, what’s realistically ahead for Mars exploration?

It would be much easier to build a city in Antarctica than on Mars but we haven’t done so. (Why? Oh yes, no one wants to live there.) Instead, we have scientific bases there, where researchers rotate in and out after a few months. Tourists visit Antarctica in the summer to see the penguins. At the largest U.S. base, McMurdo Station, there’s even a bar and a chapel.

NASA’s McKay foresees such a base as the future human footprint on Mars — at least for a century. Beyond that, who knows?

He has traveled to Antarctica for nearly 40 years, typically staying no more than two months, specifically to study the effects of the cold, dry environment for his Mars research.

But in the long, dark Antarctic winter, those scientific and military research bases largely empty out. There are no nurseries, no elementary schools, and no full-time residents.

“I go there for a season and contribute to the research and then come home,” McKay said. “I don’t want to take my family there.”

McKay, who grew up watching Star Trek, still hopes that the “long, long, long-term vision” of humans on other planets will one day materialize.

“The problem with some of the current thinking is that it jumps from zero, right now, from one or two robotic missions to, OK, let’s set up a million people on Mars, with nurseries and kids and everything,” he said. “That’s crazy.”

“Humans moving into space, I think that is inevitable,” McKay said. “But it might be that it takes thousands of years.”