Simulated Galactic Cosmic Rays effects on fungal materials: towards biotechnological radiation protection for space habitats

Human space exploration is on an upward trajectory with new space stations being manufactured for scientific experiments, industrial development, and space tourism. These spacecraft in LEO and MEO will take advantage of Earth's magnetic field for radiation protection. Astronauts on the International Space Station receive an average radiation dose of 25 µSV/hour; around 250 times greater than the average sea level dose rate. Solar activity can create an increased level of radiation that requires astronauts to stay sheltered while the solar storm hits. The Lunar Gateway, another space station, is under construction and will orbit the Moon, where it will be subjected to 77 µSV/hour deep-space radiation. As we venture into deep space to establish a permanent human presence, radiation reduction both for space habitats in a partial gravity environment and for spacecraft in microgravity is required to ensure the safety of the crew, crops, and sensitive equipment. Fungi have been studied for decades, and their radiation absorption capabilities for some types of ionizing radiation have been established. Still, fungi have never been tested to see how much radiation reduction they can provide against Galactic Cosmic Rays. This paper will present the data of the heavy ion radiation experiment carried out at the NASA Space Radiation Laboratory (New York, US) with Aspergillus niger, Cladosporium sp. and Cryptococcus neoformans. Fungi present a promising avenue for increasing the safety of future space exploration.