Future moon explorers will be bombarded with two to three times more radiation than astronauts aboard the International Space Station, a health hazard that will require thick-walled shelters for protection, scientists reported Friday.
China’s lander on the far side of the moon is providing the first full measurements of radiation exposure from the lunar surface, vital information for NASA and others aiming to send astronauts to the moon, the study noted.
Astronauts would get 200 to 1,000 times more radiation on the moon than what we experience on Earth—or five to 10 times more than passengers on a trans-Atlantic airline flight, noted Robert Wimmer-Schweingruber of Christian-Albrechts University in Kiel, Germany.
“The difference is, however, that we’re not on such a flight for as long as astronauts would be when they’re exploring the moon,” Wimmer-Schweingruber said in an email.
Cancer is the primary risk.
“Humans are not really made for these radiation levels and should protect themselves when on the moon,” he added.
Wimmer-Schweingruber said the radiation levels are close to what models had predicted. The levels measured by Chang’e 4, in fact, “agree nearly exactly” with measurements by a detector on a NASA orbiter that has been circling the moon for more than a decade, said Kerry Lee, a space radiation expert at Johnson Space Center in Houston.
“It is nice to see confirmation of what we think and our understanding of how radiation interacts with the moon is as expected,” said Lee, who was not involved in the Chinese-led study.
The German researchers suggest shelters built of moon dirt—readily available material—for stays of more than a few days. The walls should be 80 centimeters (about 2 1/2 feet) thick, they said. Any thicker and the dirt will emit its own secondary radiation, created when galactic cosmic rays interact with the lunar soil.