A No-Bake Method for Making Bricks on Mars

As anybody who’s ever tried to cram a week’s worth of clothes into a carry-on suitcase can attest, smart packing is key. Nowhere is this truer than on missions to space, where every single ounce counts. Now engineers have figured out a way to ditch one bulky item: the chemistry equipment that Martian settlers would need to turn the planet’s dirt into bricks. They published their research in the journal Scientific Reports.

While some researchers are hard at work puzzling out how to feed future colonists, others, like structural engineer Yu Qiao of UC San Diego, want to make sure we’ve got somewhere to live when we get there.

NASA is currently investigating a number of different building methods and materials, including 3-D printing. The most obvious solution might just be for settlers to make building materials out of Martian soil—or it would be, if the soil’s chemical composition weren’t so tricky. Researchers have come up with ways to transform the dirt into bricks, but these involve complex chemistry or bringing along bulky equipment like nuclear-powered kilns.

Qiao and his colleagues thought there might be a way to simplify the chemical approach. They analyzed the soil and its physical properties, hoping to reduce the number of polymers needed to bind the loose sediment into a solid, strong object.

They reduced the number, all right. Their results showed that the soil could be successfully compressed into dense chunks without any polymers at all. The same iron oxide that gives the planet its rusty color can also help bind soil particles together.

Even without rebar, the new bricks are stronger than steel-reinforced concrete. On the right is a sample after testing to the point of failure. Image Credit: Jacobs School of Engineering/UC San Diego.

The new bricks are also surprisingly tough, able to withstand more force and pressure than steel-reinforced concrete. Best of all, making them uses a no-bake recipe. The soil can be air-dried and compressed using flattened pistons.

Qiao views his team’s progress as a pragmatic but vital contribution to the future. “The people who go to Mars will be incredibly brave,” he said in a statement. “They will be pioneers. And I would be honored to be their brick maker.”

Header image courtesy of NASA/JPL.