Establishing a colony on Mars would take more than habitat modules and life-support systems: it would take a dependable supply of metal. Shipping every tonne from Earth costs tens of millions of dollars and takes months, which is why researchers are looking for a closer source — the asteroids drifting between the planets.
A team at EPFL in Switzerland has calculated how asteroid mining could supply a Martian settlement directly. Millions of asteroids roam the Solar System, and metal-rich M-type asteroids carry large quantities of iron, nickel and other useful metals — in effect, enormous ore deposits moving through space. Using a computer program, the researchers modeled thousands of supply-chain combinations, factoring in the energy needed to travel between Mars and different asteroids, how much metal could realistically be collected, and the fuel required to return.
Their cautiously optimistic conclusion: carefully selected asteroids could be reached with existing spacecraft technology, and some carbonaceous asteroids contain carbon and water ice that could be processed into rocket propellant in space — meaning spacecraft would not have to carry all of their return fuel from Earth. Choosing the right asteroid is critical; a poorly chosen target could consume more fuel than the metals it yields are worth.
The study does not mean space mining is imminent — humanity is still far from its first mine in orbit — but it suggests the logistics problem is solvable. A future supply network could move metals from asteroids to Mars using propellant produced from asteroid resources themselves.
