Once space exploration gathers steam, experts see space miners targeting water on the moon and on asteroids as a feedstock to make rocket fuel, among other useful materials. Source: Marcos Silva/iStock via Getty Images/Getty Images Plus.

Breathe easy, earthling miners.

As government agencies and private enterprises push to exploit space resources, there is little chance that metals and other materials from nearby space rocks, moons, planets and the million-plus asteroids in the Main Belt between Mars and Jupiter will flood Earth markets any time soon, several space resource experts told S&P Global Commodity Insights.

To be sure, there are lucrative near-term opportunities, such as platinum from metal-rich asteroids. But bulkier materials such as copper and iron ore are long set to remain the domain of Earth's well-established mining industry, experts said. Instead, the evolution of space mining will likely be a slow burn, gaining thrust as space exploration expands and extraterrestrial industry and supply chains emerge.

"It may [always] be more expensive to mine on the moon when you could just strip mine in the Amazon or wherever," said Ian Crawford, a professor of planetary science and astrobiology at the University of London.

Lunar Industries

Over the next couple of decades, space mining will focus heavily on resources needed by space missions, experts said. In this, the true "gold" of space may not be a metal at all — it could be water.

As launch costs to space decrease and commercial activity picks up, space-faring rockets must refuel. About 80% of the mass of typical rocket fuel is oxygen, and the other 20% is hydrogen or methane, according to Phil Metzger, a planetary physicist at the University of Central Florida who worked at NASA for decades as an engineer and physicist. Both oxygen and hydrogen can be made by separating water into its component elements.

Mining and refining oxygen and hydrogen in space from the moon and asteroids looks like it will be a lot cheaper than shipping it from Earth, experts said.

"I am optimistic about the economics of it," said Metzger. "There's going to be customers for this product not too far in the future."

Lunar soil can contain more than 40% oxygen by weight that is bound up in minerals, according to scientists. Likewise, the moon and near-Earth asteroids contain ice, which is rich in both hydrogen and oxygen, according to NASA.

To access these elements, private companies and government will need to build out moon-mining infrastructure to melt ice and split the water into oxygen and hydrogen. Or they could mine lunar soil and rocks and bake the oxygen out of it.

"Within about 15 years [of starting moon mining], the modeling shows that you can outcompete Earth-launched water anywhere in the solar system, including low-Earth orbit," Metzger said.

This is because Earth's strong gravitational field means that about 98% of the mass of an Earth-launched rocket must be fuel, while just 2% is the payload, Metzger said. The ratio for moon-launched rockets — where gravity is much weaker — is far less at about 50% fuel and 50% payload.

"It's much more efficient to get that propellant from the moon," said Kevin Cannon, an assistant professor of geology and geological engineering with the Colorado School of Mines' space resources program.

Eldon Tyrell not ready to invest

Experts picture space agencies such as NASA subsidizing the market for a long time while partnering with established and upstart companies to build and service emerging space markets. For example, they pointed to NASA's Artemis moon program, where the US space agency is tapping companies such as Blue Origin and SpaceX, among others, to provide services.

However, experts do not see a get-quick-rich scheme in the making.

"We're still talking about humans living on Mars or the moon like the way they live in Antarctica," said Paul Byrne, associate professor of earth, environmental and planetary sciences at Washington University. "It's not a commercially viable thing. It's extremely difficult. It's a risky thing, and it [will be] supported by government funding."

So far, capital markets do not appear to be lining up to fund space mining endeavors at a scale anywhere near the levels for enterprises targeting Earth resources.

"While the frontier is limitless, I see a lot more promise in the next 20 years developing technologies that can see beneath the surface of the Earth," said Rick Rule, a veteran mining investor and former president and CEO of commodities asset manager Sprott U.S. Holdings Inc.

While Rule doubted that he would invest in space mining within his lifetime, he expressed interest in the emerging sector and noted that space mining is starting to be taken seriously by respected institutions, including the Colorado School of Mines. After the sector gains much more scale, Rule said capital markets in places such as Canada, a heavyweight in global mining and exploration financing, would back more space ventures.

Executives at space mining startups have said that private equity is key to funding efforts, at least so far. Teun van den Dries, CEO of Denver-based Karman+, which aims to launch its first asteroid-mining mission in early 2026, said angel investors and family offices have an appetite for the bets on space mining.

"As we move down the risk curve and the timelines start to compress, we expect this to become a gold rush unlike any we have seen in the past," van den Dries said.

Another way to attract investors is to show promise in more down-to-earth technological innovation.

"Most space mining companies work on the idea that someone else will pay their bills until they can mine an asteroid. We at AMC do not," said Mitch Hunter-Scullion, founder and CEO of London-based Asteroid Mining Corp. Ltd., which is developing robotics to explore both the moon and asteroids. "We develop cutting edge robotic platforms with real commercial value on Earth — working under the principle that if you want to be a space trillionaire, then becoming an earth billionaire is a bloody good starting point."

Planet Express platinum delivery

Alongside water, experts see real potential in platinum as a material that space miners may exploit in the near term. The metal-rich near-Earth asteroids, which companies such as AstroForge Inc. are targeting, could hold vast amounts of platinum group metals.

Just one near-Earth asteroid alone, 1986 DA, may contain 903,000 metric tons of platinum, according to an October 2021 study published in the Planetary Science Journal. If all the metal could be mined, it would be enough to supply Earth markets for over 5,000 years, based on the Terran, or Earth-based, platinum industry's output in 2022.

Still, experts said mining of these asteroids — so far untested — is unlikely to overwhelm Earth's platinum markets any time soon. Return missions will take at least five years once they start and will only bring back a small fraction of the industry's annual output, at least at first.

Metzger, optimistic about the prospects of platinum mining missions, said forays to near-Earth asteroids may prove profitable. But, small in scale, they would probably only account for a few percent of the output of the platinum market on Earth.

"They may need to operate at a loss for a number of years, but they should be able to start producing revenue pretty quickly," Metzger said.

Cannon, from the Colorado School of Mines, was more skeptical, casting the economic prospects in asteroid-sourced platinum group metals as marginal.

"We're seeing the prices of those [metals] drop, especially as we transition to electric vehicles," Cannon said.

Consumers are increasingly buying battery electric vehicles, which require less platinum group metals than internal combustion engine vehicles. The latter uses platinum group metals in catalytic converters, which clean exhaust from burning fossil fuels.

Still, if platinum mining in space proved profitable, miners might find ways to scale it up and flood markets, driving down prices on the back of lower cost supply. This could open up doors for platinum rather than close them, Crawford said.

"If [platinum group metals] became ridiculously cheap, it might be a bad thing for the jewelry industry, but it might not be a bad thing for the world economy," Crawford said. "Because they do have uses."

Crawford drew a comparison to aluminum, which was once a rare and expensive material but is now a relatively cheap metal.

Psyched!

Another alluring target in our inner solar system is the asteroid belt beyond Mars. It contains some of the biggest deposits of metals — including platinum group metals — on metal-rich asteroids such as Psyche.

The Psyche asteroid measures about 222 kilometers in diameter and is 30% to 60% metal, mostly in the form of iron and nickel, but also platinum group metals, according to NASA. For context, 2022 production of iron ore on Earth totaled 2.36 billion metric tons, according to S&P Global Market Intelligence data, or about 0.0000001% of Psyche's mass of 22.9 quadrillion metric tons.

But the asteroid belt's distance to Earth makes retrieving its metals expensive, experts said. Rather than supplying Earth with metals, they see asteroids such as Psyche as deposits for space colonists to tap after they build self-sustaining communities beyond Earth.

In this regard, some experts speculate about the distant fate of Earth mining. Should humans colonize the solar system, and heavy industry gain a foothold in space, future generations may want to avoid impacts from mining on the only planet known to harbor life.

"There'll be a point where it may not be an economic decision, but it might be a societal one," Byrne said. "It will have a more palatable footprint, environmentally, to [mine] from an asteroid."