Why are scientists shooting mushrooms into space?

Floating 350 kilometers

above the Earth's surface, astronauts aboard the Soviet space station

Mir made a frightening discovery. Their once clear porthole was clouded

with a green and black web-like substance. Soon, these growths were found

throughout the shuttle, blanketing air conditioners

and corroding control panels, putting both the station's integrity

and the astronauts' lives at risk. The invaders were identified as several

species of Earth-derived fungi that had, against all odds,

survived the journey to space. And once there, they'd adapted

to the microgravity and radiation-dense environment. Thankfully, the crew managed

to keep these threats at bay, and Mir remained in orbit

for the next 13 years. During that time, scientists have learned

that fungi have the potential not to hinder space travel,

but to help it. In fact, these resilient,

often overlooked organisms may be the key to our future

on other planets. Once outside the Earth's protective

magnetic field, most living things need serious protection to survive the DNA-damaging

cosmic radiation in space. But that's not the case for some fungi. Many species produce a unique

form of melanin, a pigment that safely absorbs

high levels of radiation and, in some cases,

uses this energy to fuel growth. Even if dangerous levels of radiation make

it past this homegrown armor to damage DNA, many fungi have robust repair

systems that spring into action, cutting out and restoring

defective sequences. And radiation isn't the only cosmic

element fungi can withstand. Their hardy spores sport thick cell walls that allow them to survive

extreme temperatures. So, how might we utilize fungi in space? Well, a big obstacle to settling

on other planets is figuring out how to source

the materials needed to build suitable habitats. There are two common solutions. First, we could send these supplies

up from Earth. But this is expensive— it costs roughly $10,000 for each

kilogram of weight added to a launch. Alternatively, we could use

what's already there. Homes could be built from the dust

and fragmented rock that coat the surface of other planets,

which is called regolith. Yet this would require a shipment of

large, heavy, energy-intensive machinery to collect, heat, and compact the loose

regolith into something usable. That's where fungi come in. Most fungi have hair-like root structures

called mycelia. And as they grow, they easily bind

nearby materials, whether it be wood chips,

sawdust, or regolith. The result is a dense, interconnected web that makes a surprisingly durable

building material that's both thermal and

radiation protective. Scientists working with NASA's Innovative

Advanced Concepts program have devised plans for using

this technology to grow fungal homes on other planets. First, lightweight, flexible bags seeded

with dehydrated spores are launched to their new home. Once they've arrived, accompanying rovers

source water for rehydration and regolith for binding. Alternatively, the bags could be preseeded

with a lightweight binding material, like dehydrated wood chips. And there's another essential ingredient

to these packages, cyanobacteria, which provide the fungi with nutrients

and convert sunlight into oxygen. The mycelia grow to fit the shape

of their bags, creating the walls, roof, and even the

furniture of these fungal abodes. Once completed,

maintaining these buildings would likely be relatively simple, as any cracks could be

reseeded and regrown. Scientists could engineer cyanobacteria

to alert residents if repair is needed, by glowing when oxygen or pressure levels

in the habitat dip. Of course, there's still a lot of work

out there before these lightweight habitat packs

are ready for launch. In the meantime, researchers have begun

to iron out the details by growing these sustainable,

carbon-negative fungal habitats right here on Earth. And housing is just one of many possible

uses for fungi in space. Communities will need to grow

their own food, yet soil suitable for plants isn't

readily available off Earth. Fungi can release a variety

of chemical-degrading enzymes capable of dissolving

carbon-rich asteroids into soil. And they can also be engineered

to mine and extract metals, like aluminum and iron, which could allow space colonies

to source these valuable ores locally. Fungi have come a long way

from their space hazard beginnings and will undoubtedly continue

to break the mold.