When SpaceX launched its latest rocket to deliver a new load of cargo to the International Space Station (ISS) this morning, it also contained a series of experiments for the astronauts to conduct. One of these might seem fairly innocuous at first: an experiment to grow certain strains of fungi. But these are not any fungi. Collected from the Chernobyl nuclear disaster zone, these fungi can feed on radiation, and could help future space missions.
After visiting the Chernobyl Exclusion Zone, scientists realized there may be more to the "black fungi" that were thriving in the region despite the high levels of radiation present. The numbers of these fungi were found to have risen dramatically following the meltdown, and on further examination, found to grow towards radiation sources, in a manner that appeared to imply that they were trying to reach them.
It turns out that the fungi might be harnessing melanin – the pigment found in skin that helps to protect against UV damage – in order to break down radiation. Not radioactive compounds, but radiation itself. By harvesting its energy, the fungi is able to use the radiation in order to grow, a concept that has been of interest to scientists as a potential way to solve the problem of feeding astronauts during long space flights or when they colonize other planets.
But scientists are not really thinking that future star travelers will be chowing down on bowls full of black fungi (said to resemble the mold found on dirty shower curtains). Instead, by figuring out how the fungi thrive, scientist hope to harness this knowledge for further applications. Earlier research has suggested that exposure to radiation caused the fungal melanin pigment to change shape, allowing it to break the radiation down and thus get energy out of it.
While it might be possible to alter the shape of the melanin found in human skin, scientists speculate that this wouldn’t work in the same way as energy generation in plants. It is hoped, though, it might be possible to use this knowledge to enable plants to grow in more extreme environments where there are high levels of radiation, such as on other planets like Mars.
It is important to stress that this is all hypothetical at the moment. However, it is questions like these that this latest series of experiments will hopefully illuminate. The astronauts will be growing eight species of radiation-munching fungi for 14 days, while on Earth other scientists will be doing the same, allowing them to compare the strains when they return to solid ground.