Some Earth microbes could survive on the Moon, particularly in the deep, permanently shadowed regions near its south pole, a NASA and University of Maryland study has found.
The finding raises concerns about human missions inadvertently carrying microorganisms to the lunar surface and potentially contaminating areas that scientists hope to study in their pristine state.
Researchers led by planetary scientist Prabal Saxena of NASA’s Goddard Space Flight Center used elevation maps and temperature data from NASA’s Lunar Reconnaissance Orbiter to simulate conditions at potential landing sites for the Artemis III mission.
They examined how five common spaceflight microbes, including the human skin bacterium Staphylococcus aureus and the fungus Aspergillus niger, might respond to lunar conditions.
The computer models identified several potentially survivable niches in the Moon’s shadowed polar regions. All five microbes could remain dormant for at least 24 hours under these conditions, while Aspergillus niger could potentially survive for up to a week.
The study, published in Science Advances, suggests that microbial material carried by astronauts could persist longer than previously assumed. Even dead or dormant microorganisms could complicate the study of lunar soil by contaminating samples and making it harder to distinguish the Moon’s natural chemistry from material introduced by humans.
The researchers said understanding the microbial baseline of potential landing sites will be important as human activity on the Moon increases. The work could also help scientists distinguish Earth-borne contamination from possible signs of life when future missions search for life beyond Earth.
The team is also examining how human missions could introduce biological contaminants to other lunar environments.