In the future, when astronauts set foot on the Moon, Mars and beyond, they will be able to grow space houses out of organisms that breathe and eat, like mushrooms.
Space houses made from fungus like mushrooms could replace glass or steel, says NASA. This green technology could be adopted on Earth as well, as about 40% of carbon emissions come from construction on Earth. There is an ever-increasing need for sustainable and affordable housing here as well.
"When we design for space, we are free to experiment with new ideas and materials with much more freedom than we would on Earth. And after these prototypes are designed for other worlds, we can bring them back to ours," says Lynn Rothschild, the principal investigator on the early-stage project in a statement.
NASA began exploring this idea in 2018. At the heart of this technology is a structure that gives mushrooms its shape -- mycelium. These structures, which grow into mushrooms, are sturdy and flexible. This property makes mycelium attractive. They can be manipulated to form new structures – ranging from a material similar to leather to form the building blocks for a Mars habitat. In fact, they are already used to make fire retardants.
"Right now, traditional habitat designs for Mars are like a turtle — carrying our homes with us on our backs – a reliable plan, but with huge energy costs. Instead, we can harness mycelium to grow these habitats ourselves when we get there,” says Rothschild.
Future human explorers will carry a basic structure built out of a lightweight material with inactive fungi. “Upon arrival, by unfolding that basic structure and simply adding water, the fungi will be able to grow around that framework into a fully functional human habitat – all while being safely contained within the habitat to avoid contaminating the Martian environment, NASA says.
The space house comes equipped with three layers, with each layer responsible for carrying out specific functions. Frozen water ice, perhaps tapped from the resources on the Moon or Mars, will make up the outermost layer. That water protects against the harsh space radiation and leaks into the second layer made from another organism: cyanobacteria. This bacterium will provide oxygen and food to the fungus: it uses energy from the Sun to convert water and carbon dioxide into oxygen and fungus food.
Forming the final layer is mycelia. These pieces come together in an elegant habitat concept with a three-layered dome, says NASA.
NASA will ensure that the mycelium does not contaminate Mars or any microbial life that is already there. They have designed the fungus in a manner that incapacitates its ability of surviving outside its habitat. Its applications go beyond constructing habitats, mycelia could be used for water filtration and to extract minerals from wastewater and even self-generating habitats capable of healing themselves, says Rothschild.
The harsh environments of the Moon and Mars will require new ways of living – growing homes instead of building them, mining minerals from sewage instead of rock. NASA adds, “By turning to the elegant systems of our own natural world, we can design solutions that are green and sustainable. Whether on distant worlds or our own ever-changing Earth, fungi could be what brings us boldly into the future.”