In space, astronauts often live with the risk of being exposed to too much radiation, which could cause severe damage to their long-term health. Researchers have discovered a strain of fungus that might help resolve this issue. This particular fungus, called Cryptococcus neoformans, apparently has the ability to feed on radiation and was discovered at Chernobyl.
Fungi in space
“The fungi contains high levels of melanin, a pigment that turns skin darker. That melanin absorbs radiation and turns it into chemical energy, similar to how plants turn carbon dioxide and chlorophyll into oxygen and glucose through photosynthesis… This specific process is dubbed radiosynthesis. Melanin absorption is an intriguing property that could be used to protect astronauts in space,” according to CNET.
Scientists at NASA are investigating whether the melanin from the fungi can be extracted in an economically viable way so as to create a sunscreen to be used in space. Some samples of melanin from the fungus have already been sent to the International Space Station (ISS) where researchers are testing out the efficacy as a shield against radiation. If successful, not only would the material protect space structures and astronauts, but it could also benefit people back on Earth.
Figuring out how the fungi absorb radiation will enable scientists to develop treatments for astronauts who risk being exposed to radiation for extended periods of time. Last year, a team of researchers beamed heavy ions and x-rays at a common black mold called Aspergillus niger with the aim of finding out the effects of radiation on mold. This specific strain of mold is found in the ISS quite often. The team fired radiation in excess of what is found on the surface of Mars, which comes in at just 0.2 gray per annum. “Gray” measures the amount of absorbed radiation energy.
“The researchers discovered that the spores could survive radiation doses of 500 to 1000 gray, depending on which type of radiation they were exposed to. Humans, by contrast, get radiation sickness at doses of 0.5 gray and are killed by 5 gray… the spores survived large amounts of high-energy ultraviolet radiation, which is commonly used as a hospital disinfectant and has been proposed for sterilizing the surfaces of spacecraft,” according to Science.
Fungi might one day also be used to make homes on the moon and Mars. NASA’s Ames Research Center myco-architecture project is already prototyping technologies that are capable of growing habitats on such alien environments. The underground threads that make up the main part of the fungus, called mycelia, are being deeply researched as part of the project.
“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 mycelia to grow these habitats ourselves when we get there,” Lynn Rothschild, the principal investigator on the early-stage project, said in a statement (NASA).
The ultimate aim is a future where humans can transport a compact habitat made of fungi to Mars, the Moon, and even other worlds. After arriving at these destinations, the astronaut simply needs to unfold the basic structure and add water. The fungi will grow around the structure and end up creating a fully-functional living habitat. Scientists have already grown bricks and stools from mycelia. As such, a fully functional home should be achievable in a few decades.