Martian Soil Could Be Used to Build a Colony
In all likelihood, a Martian colony won't resemble a silver city rising in stark contrast to the planet's signature red soil. Instead, it will blend right in, especially if a new, intriguing discovery pans out.
Engineers from the University of California in San Diego have created bricks composed of simulated Martian regolith (soil). Amazingly, these basic building blocks turned out to be stronger than steel-reinforced concrete!
Creating the bricks was surprisingly simple. Yu Qiao, a Professor of Structural Engineering, and his team dried out simulated Martian soil, compressed it at high pressures in steel molds, and then subsequently allowed it to dry again. The resulting blocks were incredibly strong and had a permeability similar to dense rocks. This latter feature is important, because it means a structure built with the bricks could be adapted to hold an atmosphere, which is vital on a planet as inhospitable as Mars, where the air is extremely thin and the temperature frequently falls to minus 100 degrees F.
The secret ingredient allowing for the formation of these bricks seems to be the iron oxide that gives the Martian soil its patented red hue. Under crushing pressure, the iron oxide morphs into a denser form, binding the surrounding regolith together in the process.
Earlier this year, a panel of current and former NASA scientists speaking at MIT's New Space Age Conference agreed that a Mars colony would need to be self-sustaining. Utilizing the planet's soil as a building material would be integral to that aim. Astronauts would merely need to haul a device to form the bricks, along with any necessary materials to make the structures they build habitable, such as radiation shields and insulation.
Qiao and his team add that their procedure could be adapted to additive manufacturing, akin to 3D printing, meaning that a wide array of shaped bricks and structures could be produced.
Structures made of Martian soil may not sport a futuristic look, but they would get the job done, representing just the sort of ingenuity needed for humans to colonize the Red Planet.
Source: Brian J. Chow, Tzehan Chen, Ying Zhong & Yu Qiao. Direct Formation of Structural Components Using a Martian Soil Simulant. Scientific Reports. DOI:10.1038/s41598-017-01157-w