Martian Metalworking: A Beginner's Guide to Making Metal on Mars

“The Martian soil contains metallic treasures ready to be extracted and forged into valuable, shiny objects.”

Mars is orange because of the iron oxide (rust) in the soil.

Extracting the iron oxide from the Martian soil and transforming it into metal is a key step in kickstarting the industrial revolution on the Red Planet.

—

Iron oxide is made up of iron and oxygen. On Earth, it is commonly found as rust on the surface of iron or steel when exposed to oxygen and water. It is also used as a pigment in paints on Earth, and soon on Mars too.

The concentration of iron oxide in the soil on Mars varies by location and can range from less than 1% to over 20%.

—

To turn iron oxide (Fe2O3) into metal, it needs to be reduced to its elemental form which is pure iron (Fe).

This can be achieved by using hydrogen gas, high temperatures, a lot of energy, and a process called the reduction-oxidation reaction (REDOX).

During the REDOX process, the iron oxide from the soil gives electrons to the hydrogen gas (the reducing agent), creating iron metal and producing water vapor as a by-product.

Iron oxide from the soil (Fe2O3) + Hydrogen gas (3 H2) --> Iron metal (2 Fe) + Water vapor gas (3 H2O)

The water vapor and any leftover hydrogen gas can be collected and used for other purposes, such as the production of rocket fuel (CH4) when mixed with carbon dioxide from the atmosphere."

Meanwhile, the newly-furnaced Martian iron is used to construct superstructures.

The Martian soil also contains other valuable treasures, such as nickel, cobalt, titanium, and possibly even gold.

Subscribe below to the ‘Building on Mars’ newsletter to stay connected.