When astronauts return to the moon or travel to Mars, how will they shield themselves against high levels of cosmic radiation? A recent experiment aboard the International Space Station suggests a surprising solution: a radiation-eating fungus, which could be used as a self-replicating shield against gamma radiation in space.
The fungus is called Cladosporium sphaerospermum, an extremophile species that thrives in high-radiation areas like the Chernobyl Nuclear Power Plant. For C. sphaerospermum, radiation isn’t a threat — it’s food. That’s because the fungus is able to convert gamma radiation into chemical energy through a process called radiosynthesis. (Think of it like photosynthesis, but swap out sunlight for radiation.)
The radiotrophic fungus performs radiosynthesis by using melanin — the same pigment that gives color to our skin, hair and eyes — to convert X- and gamma rays into chemical energy. Scientists don’t fully understand this process yet. But the study notes that it’s “believed that large amounts of melanin in the cell walls of these fungi mediate electron-transfer and thus allow for a net energy gain.”