With more spacecraft on Mars than any other planet that isn’t earth, it’s safe to say humanity’s curiosity with the red planet isn’t going away anytime soon. While these missions are unmanned, the reality is that one day humans will set foot on this planet. This has many in the building design and construction industry dreaming of how we’ll get there, in something resembling a life-sustaining environment.
So, what could construction on Mars look like?
Logistics prove problematic
For starters, transporting building materials to Mars is highly problematic. Chemical and Engineering News estimates it costs about $4,000 to launch a kilogram of material to low earth orbit alone, meaning the price would be exponentially higher given the 33.9-million-mile minimum distance to Mars from Earth.
Any new inhabitants of the red planet will have to do what colonists have always done: Use the materials they have at hand to build shelters. On Mars, that material is regolith, a dusty, pulverized rock layer deposited throughout the solar system over billions of years by asteroid collisions. “It’s a ready-made construction material—crushed rock—sitting on the surface of the planet,” [says Robert P. Mueller, senior technologist for advanced products development at the Swamp Works, an innovation laboratory he cofounded at NASA’s Kennedy Space Center]. “All we have to do is develop the technology to use that aggregate that already exists and somehow bind that aggregate together.”
Though no spacecraft has yet to return to Earth with an actual sample of regolith, NASA scientists are looking at samples collected from rovers and testing to see if it can be used as a replacement for some concrete components.
NASA’s 3D-Printed Habitat Challenge in 2019 awarded $500,000 to New York–based AI SpaceFactory for coming up with a design that incorporates their own formula for a “Martian Polymer.” Their project, named MARSHA (for Marsh Habitat), incorporates a plan to use 3D printing, sending machines in advance of humans to harvest and process raw materials and assemble structures. Per the company’s website:
In collaboration with Techmer PM, we’ve formulated an innovative mixture of basalt fiber extracted from Martian rock and renewable bioplastic (polylactic acid, or PLA) processed from plants grown on Mars. This recyclable polymer composite outperformed concrete in NASA’s strength, durability, and crush testing. ASTM lab tested and certified to be two to three times stronger than concrete in compression, our space-grade material is also five times more durable than concrete in freeze-thaw conditions.
Biomimicry to the rescue?
Researchers at the Singapore University of Technology and Design may have come upon a discovery to help with limited construction resources. They’ve discovered that the organic polymer chitin, which is contained in the exoskeletons of insects and crustaceans, can be transformed into a viable building material that would require minimal energy and no need for special equipment. Researchers also noted that since insects may be a key component of protein for those inhabiting the Martian base, chitin could be a by-product of the food supply. Per Wired:
“Bioinspired manufacturing and sustainable materials are not a substituting technology for synthetic polymers, but an enabling technology defining a new paradigm in manufacturing, and allowing to do things that are unachievable by the synthetic counterparts,” said [research report co-author Javier Fernandez]. “We have demonstrated that they are key not only for our sustainability on Earth but also for one of the next biggest achievements of humanity: our transformation into an interplanetary species.”