Astronauts sent to Moon missions are subjected to daily radiation of 1,369 microsieverts or an equivalent of 200 to 1,000 times more radiation than what people experience on Earth. This was the first time that scientists were able to give an exact number to the amount of Moon radiation that astronauts endure when exploring the lunar surface.
The number was derived from Lunar Lander Neutrons and Dosimetry experiments conducted aboard China’s Chang’e 4 lander. The study is published in the journal of Science Advances.
“On the surface of the Moon, this (space radiation) consists of the chronic exposure to galactic cosmic rays and sporadic particle events. The interaction of this radiation field with the lunar soil leads to a third component that consists of neutral particles, i.e., neutrons and gamma radiation,” the study reads.
The present finding is significant as NASA prepares to send the first woman and the next man on the Moon for the Artemis mission in 2024. The astronauts will explore the lunar surface for a week and are expected to complete two moonwalks for the mission.
Physicist Robert Wimmer-Schweingruber of the University of Kiel in Germany, a co-author of the study, compared the measured dose to what passengers experience when flying on an intercontinental flight from New York City to Frankfurt. Daily radiation of 1,369 microsieverts on the lunar surface is 10 times more than what passengers received when the plane is above portions of the protective atmosphere, Wimmer-Schweingruber said in a follow-up report related to the study.
The follow-up report clarified that the radiation measurements remain safe for astronauts, even for long-term lunar exploration. There is a regulation in place prohibiting NASA from going beyond the accepted level to which a mission could increase the risk of astronauts dying from cancer. The level is currently set to no more than 3% and the dose of 1,369 microsieverts remains below that.
Nevertheless, Wimmer-Schweingruber and fellow researchers highlighted that Moon bases covered with at least 50 centimeters of lunar soil can protect astronauts from space radiation. Additionally, a chamber with about 10 meters of water can also protect astronauts from radiation in case of solar storms. If such parameters are in place, astronauts will have no problem staying on the Moon for up to six months.