In the coming decades, space agencies and private ventures want to begin sending humans to Mars. Some of these organizations are actively planning on establishing the first human settlement there.
With all this planning, it's fair to say that the idea of colonizing Mars may be moving from the realm of science fiction into the realm of true possibility. However, this also raises all kinds of issues, which go far beyond the usual technical hurdles and cost assessments.
There are also valid questions about whether or not humans could survive on Mars in the long-term. And there are ethical questions concerning how humans might transform Mars' environment - not just through full-scale terraforming, but through any and all alterations to the Martian landscape.
Taking all of that into consideration, there is also the entirely valid question of whether or not a colony on Mars would be economically viable in the long-run. Most serious proposals to create a Martian settlement makes a point of addressing the issue of self-sufficiency in terms of resources.
So, it is important to consider whether or not we can build a working economy on Mars to go along with a human settlement. What challenges need to be overcome in order to do that, and (above all) is it worth all the fuss?
Mars as the "new frontier"
To enthusiasts of Martian colonization, the hope of a "new frontier" comparable to the exploration and colonization of North America is often raised. Putting aside the many ugly aspects of that phase in our history (i.e., conquest, genocide, and slavery), which are in any case not likely to be replicated on Mars, there is a clear logic to this approach.
By presenting the Martian landscape as a new frontier, proponents of Martian colonization are appealing to people's sense of adventure. Living in such an environment would be very challenging, but that's precisely what makes it appealing to many people.
By journeying to Mars and being the first to live on the Red Planet, Martian colonists would effectively be "pioneers". And there's something to be said for how hard tasks bring out the very best in people. As President John F. Kennedy said in his famous 1963 speech at Rice University:
"We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."
Natural wealth on Mars
Another appealing aspect that often accompanies this "frontier" talk is the idea that Mars is rich in resources. With its abundant mineral wealth, there are those who believe that colonists traveling to Mars will be taking part in another "gold rush" or some other mineral-fueled economic boom.
On its face, this argument has some merit. In terms of its structure and composition, Mars is very "Earth-like". It is composed primarily of metals and silicate minerals which are differentiated between a metallic core and a silicate mantle and crust.
In addition, there is evidence of the existence of plentiful metals on Mars that could be useful for industrial applications. The evidence for the presence of these minerals includes studies of Martian meteorites, as well as evidence gathered by robotic landers and rovers operating on the surface.
NASA missions like the Viking I and II landers, as well as the Mars Pathfinder, Spirit and Opportunity rovers, have identified aluminum, iron, magnesium, and titanium while examining samples of Martian soil. Scientists have also found evidence of trace amounts of other minerals, such as chromium, lithium, cobalt, nickel, copper, zinc, tungsten, and gold.
In addition, the Opportunity rover found small spherical structures (known as "blueberries") on the surface. These were made of hematite, a common form of iron oxide. Both Spirit and Opportunity have also found meteorites composed of iron-nickel sitting on the surface. These could be all collected and harvested by colonists.
Of course, there's a flipside to that coin. When it comes right down to it, Mars has very little in common with Earth's "frontiers". For starters, the environment is entirely hostile to life as we know it and has conditions that make even the harshest environments on Earth look pleasant by comparison.
The atmosphere on Mars is incredibly thin, ranging from a low of 30 Pa on Olympus Mons to a high of 1,155 Pa (1.155 kPa) in the Hellas Planitia (one of the largest impact craters on Mars). On average, the atmospheric pressure is about 0.636 kPa on the surface, which is less than 1% of what we have on Earth (101.325 kPa).
In addition to being incredibly thin, the Martian atmosphere is also toxic to humans and mammals. Whereas Earth's atmosphere is made up of 78% nitrogen and about 21% oxygen gas, Mars' atmosphere is composed of 96% carbon dioxide and trace amounts of argon, nitrogen, and water vapor.
Mars is also very desiccated, to the point that deserts on Earth seem wet by comparison. On average, water vapor makes up a fraction of a percent of the atmosphere (0.0210%). On Earth, this varies, but water vapor in our atmosphere still averages around 1%. In fact, the vast majority of the planet's water is locked away in the poles as ice.
Temperature swings are also very extreme on Mars, ranging from 20 °C (70 °F) at midday around the equator to a low of -153 °C (-225 °F) around the poles. And since the atmosphere is so thin, heat from the Sun easily escapes. To illustrate, a person standing around the equator on Mars at noon would have warm feet (24 °C; 75 °F) but a very cold head (0 °C; 32 °F).
Due to seasonal variations in temperature, Mars often experiences dust storms that can become strong enough to cover the entire planet. These can last for months and can become so intense that they prevent sunlight from reaching the surface, leading to months of darkness and extreme cold. One such storm, which took place in 2018, caused the Opportunity rover to cease operations.
Radiation is another major hazard on the surface of Mars. In developed nations, people on Earth are exposed to an average of 0.62 rads (6.2 mSv) of radiation per year. Because of Mars' thin atmosphere and the fact that it has no protective magnetosphere, the surface receives around 24.45 rads (244.5 mSv) per year.
The situation becomes even more extreme during solar proton events (aka. solar flares). Prolonged exposure to this level of radiation would dramatically increase the risk of acute radiation sickness, cancer, genetic damage, and even death.
Then you have the gravity on Mars, which is roughly 38% of what we experience here on Earth (or 0.3794 g). While it remains unknown what long-term exposure to this level of gravity could be, numerous studies have been conducted on the long-term effects of exposure to microgravity and the results are not encouraging.
Well-known science communicator Bill Nye (the Science Guy) addressed these challenges during one of his many talks on the subject. As he put it:
"Do you know the state motto of California? Eureka! (People discovered) salmon that comes out of the Sacramento River like this (holds arms out wide). This protein just swims into your lap. And, eventually, they found their rocks are made of gold… That's why (their state motto is) Eureka. OK. You guys. If you go to Mars, it's not like that... You open the door of the spaceship (makes gasping sound), it's 20-below celsius, at least… If you really think it's cool to go to Mars, to be a pioneer or settler, to set up camp and live off the land, just go to Antarctica… Take all the scuba tanks you need for two years, and see if you think that's really for you."
However, perhaps the most compelling argument against setting up shop on Mars (or the Moon or in the Asteroid Belt, for that matter) is the distance involved. When Mars and Earth are at the closest point in their orbits, they are (on average) about 54.6 million km (33.9 million mi) from each other.
This is known as an "opposition", which refers to the fact that during these periods, the Sun and Mars are on opposite sides of the sky (as observed from Earth). This occurs about once every two years. At other times, Mars is beyond the Sun (relative to us) and appears in the same section of the sky.
On these occasions, known as a "conjunction", Earth and Mars can be as much as 401 million km (249 million miles) apart. This is a very long way to go in order to pick up ore (or other precious metal) and haul it back to Earth.
On top of that, the price for establishing a colony to support these mining activities would be astronomical. By Elon Musk's own estimates (a major proponent of Martian colonization), it could cost up to 10 trillion dollars!
Under the circumstances, it makes far more economic sense to just stay here and keep extracting raw materials from Earth.
But can it be done?
All of that being said, there are still ways that we could build a colony on Mars as well as an economy around it. In terms of precious metals and ore, a number of methods exist that would allow colonists to survey, extract, and refine Martian ores.
And when it comes to the greatest challenges, logistics, and transport, there are solutions there as well. Let's start with logistics and transport. For all uncrewed missions that have been launched towards Mars, the time it took for them to get there has typically taken 150 to 300 days.
However, these were uncrewed missions, which means they a significantly lower mass than a crewed spacecraft and could travel much faster. To solve this issue, humanity would need to develop new propulsion concepts like nuclear-thermal and nuclear-electric propulsion (NTP/NEP).
Properly realized, spacecraft equipped with nuclear engines could make the trip to Mars in just 100 days. Still not fast enough to make Mars mining or other such ventures profitable, but its an improvement all the same.
Another cost-cutting measure would be to process ores on-site and to have this performed by robots. In a recent study, planetary scientist Gary Stewart outlined how an automated facility could be established in a metal-rich crater on Mars that would be responsible for surveying, extracting, and refining metals to create finished materials and products.
The base would leverage solar panel farms, local ice, and salt deposits, and in-situ resource utilization (ISRU) to be self-sufficient. Once ores are extracted by robotic miners, they would be brought to automated foundries that would rely on 3D printing techniques to create iron-alloy products.
Similarly, precious metals like gold can be fashioned into bullion, electronic components, and even jewelry products. Based on Stewart's estimates, a daily gold production "of just 0.001 m³ can translate into multi-billion-dollar annual revenue from all precious-metal products."
Over time, this facility would not only pay for itself, but it would also allow for further automated mining facilities to be established. These could, in turn, could facilitate the creation of a Martian settlement by establishing the basis of an export economy ahead of time.
Speaking of establishing a Martian colony, it was for this very reason (in addition to reinvigorating space exploration) that Elon Musk founded the private aerospace company known as SpaceX in 2002. Intrinsic to this is the development of reusable rocket stages, which SpaceX has achieved with their Falcon 9 and Falcon Heavy launchers.
Between 1970 and 2000, the cost per kilogram to launch payloads or crews into space remained relatively stable - averaging $18,500 per kilo ($8,390 per lbs). For the Falcon 9 and Falcon Heavy, the cost to send payloads to Low Earth Orbit (LEO) is just $2,720 per kg ($1,236 per lbs) and about $1400 ($640 per lbs), respectively.
With the development of the Starship and Super-Heavy launch vehicle - an entirely reusable system - SpaceX is getting close to the point where it will be able to provide crewed launch services to orbit, the Moon, and Mars. As they state on their website, the mission timeline will begin with an exploratory mission in 2022:
"The objectives for the first mission will be to confirm water resources, identify hazards, and put in place initial power, mining, and life support infrastructure. A second mission, with both cargo and crew, is targeted for 2024, with primary objectives of building a propellant depot and preparing for future crew flights. The ships from these initial missions will also serve as the beginnings of the first Mars base, from which we can build a thriving city and eventually a self-sustaining civilization on Mars."
In recent years, Musk has indicated that this first base (Mars Base Alpha) could be assembled as early as 2028. In accordance with Musk's vision, the city would take about 20 years to build would involve 1000 Starships. By 2050, Musk hopes to have presided over the creation of a full-fledged Martian city with a population of one million inhabitants.
As for this city's economy, Musk has stated that he doesn't think mining and an export economy would be viable within the immediate future. As such, a Martian economy (he stated) would be largely based around the purchase of real estate.
The key to this is to make moving to Mars attractive. As Musk said during his famous speech, "Making Humans a Multi-Planetary Species", which he delivered at the 2016 International Astronautical Congress
"If we can get the cost of moving to Mars to the cost of a median house price in the U.S., which is around $200,000, then I think the probability of establishing a self-sustaining civilization is very high... Almost anyone, if they saved up and that was their goal, they could ultimately save up enough money and buy a ticket and move to Mars — and Mars would have a labor shortage for a long time so jobs wouldn’t be in short supply."
These sentiments echo what famed aerospace engineer and author Robert Zubrin had to say about building a Martian economy. As he summarized in a study on the topic, increasingly-cheap launch services would allow for emigration to Mars once a self-sustaining colony is established.
"Their motives for doing so will parallel in many ways the historical motives for Europeans and others to come to America, including higher pay rates in a labor-short economy, escape from tradition and oppression, as well as the freedom to exercise their drive to create in an untamed and undefined world. Under conditions of such large-scale immigration, the sale of real-estate will add a significant source of income to the planet's economy."
Another aspect of a Martian economy, according to Zubin, would come down to innovation and ideas. Essentially, the challenge of living on Mars, combined with the freedom of opportunity, would turn a Martian colony into "a pressure cooker for invention".
The licenses for these inventions would provide a steady source of income for Martian settlements (allowing for additional settlements to be built) and contribute to greater living standards on both Earth and Mars.
Forget the colony model!
Then again, perhaps the idea of a Martian economy is a round peg that we're trying to force into a square hole. Rather than trying to build an economy around the harvesting and exporting resources, perhaps we should be looking to build an economy "from the ground up".
That is the idea proposed in a 2018 study by Matthew Weinzierl, a professor at Harvard Business School. Titled "Space, the Final Economic Frontier", Weinzierl addressed the rise of the commercial space industry (aka. New Space) and the process of decentralization at its core.
Once the process of building the infrastructure that will ensure survival is complete, colonists would be able to build a local economy and political/social systems from scratch. As Weinzierl argues:
"If such space-economy visions are even partially realized, the implications for society—and economists—will be enormous. After all, it will be our best chance in human history to create and study economic societies from a (nearly) blank slate. Though economists should treat the prospect of a developed space economy with healthy skepticism, it would be irresponsible to treat it as science fiction."
In the meantime
Alas, there is still plenty to do before a self-sustaining Martian colony can be built and a viable economy built up around it. As noted already, the sheer cost of sending missions to and from Mars needs to be reduced considerably.
And while reusable rockets are a good start, there's also the matter of establishing infrastructure between Earth and Mars that will make round-trips less expensive. For this, nothing less than habitats that orbit the Moon and Mars (as well as refueling stations on both) will do.
A working fleet of reusable spacecraft like Elon Musk's Starship or NASA's planned-Deep Space Transport is also necessary. Given time, and a cost-effective means of getting people to and from Mars, a colony could spring up over time.
Assuming that this colony thrives and its people are able to extract a considerable amount of "Red Gold" from the Red Planet, perhaps exports could begin. This, in turn, would likely lead to the development of a true interplanetary economy and the end of scarcity as we know it!
- SpaceX - Making Life Multiplanetary
- Forbes - Is there a fortune to be made on Mars?
- Marketplace - The economics of colonizing Mars
- Explore Mars - The Humans to Mars Report 2019
- Reuters - Mars shows man the final frontier of circular economy
- ESA - Challenges of future urban settlements on the Moon and Mars
- Harvard - Space, the Final Economic Frontier - Matthew C. Weinzierl
- Planete Mars - An economic model for a Martian colony of a thousand people
- Lockheed Martin Astronautics - "The Economic Viability of Mars Colonization" - Robert Zubrin
- "Red Gold-Practical methods for precious-metal survey, open-put mining and open-air refining on Mars." - Gary Stewart (2019)