The Moon is the next springboard for human space exploration. Although NASA’s Apollo missions of the 1960s and 1970s demonstrated that it was safe for humans to spend a few days on the lunar surface, NASA did not take daily radiation measurements to quantify how long crews could stay on our site. satelite. And space exploration depends on it. It carries many risks, and one of them is precisely exposure to radiation from space, which can cause long-term harmful effects on health, from cataracts to cancer to neurodegenerative diseases.
Now, in a study published in the journal Science Advances , researchers have just quantified what level of radiation astronauts on the Moon can expect to be exposed to, and that’s a lot.
China’s lander, Chang’E 4 with the Lander Neutron Dosimetry (LND) instrument developed and built at the University of Kiel, has taken measurements of lunar radiation that allow the calculation of the so-called equivalent dose; vital for estimating the biological effects of space radiation on humans.
They estimate that the equivalent dose of radiation that astronauts would experience daily is about 1.3 milliSievert (a unit that measures the radiation dose received from a radioactive source), that is, 2.6 times higher than the radiation experienced by astronauts. astronauts and cosmonauts on the International Space Station (ISS). The reason is that the ISS is still partially shielded by Earth’s protective magnetic bubble, the magnetosphere, which deflects most of the radiation from space.
By comparing the measured radiation equivalent dose, on a long-haul flight from Frankfurt to New York, it is 5 to 10 times lower and on Earth more than 200 times lower. Earth’s atmosphere protects us on the surface, but the higher we climb, the more exposed we are .
Limit of two continuous months on the Moon
“Since astronauts would be on the Moon much longer than passengers flying to New York and returning, this represents considerable exposure for humans. Humans are not made to withstand radiation from space. However, astronauts can and do they should be protected as much as possible during longer stays on the moon, for example by covering their habitat with a thick layer of lunar soil, “explains Robert Wimmer-Schweingruber from the University of Kiel, whose team developed this instrument.
This level of effective radiation in one day is difficult to imagine but is higher than the Environmental Protection Agency expects the average person to be exposed in a year (1 milliSievert). An astronaut on the Moon would cross that threshold in just 38 days and 12 hours.
While visiting the Moon is not risky, living permanently on it is.
NASA plans to land humans on the Moon by 2024 under the Artemis mission and has said it has plans for a long-term presence that would include astronauts working and living on the surface.
Referencia: S. Zhang el al., First measurements of the radiation dose on the lunar surface, Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.aaz1334
