The moon is a very harsh place for life to survive. With virtually no atmosphere, the temperature difference between day and night is large, and ultraviolet rays and high-energy particles pour directly onto the surface. In such an environment, microbes from Earth have long been thought unlikely to survive for long.
However, researchers at the National Aeronautics and Space Administration (NASA) announced findings suggesting that some polar regions of the moon may contain "refuges" where Earth's microorganisms could survive for a time. The results were published in the international journal Science Advances on the 20th.
The team analyzed terrain at the lunar south and north poles, the amount of sunlight, and surface temperatures to find places where relatively low temperatures are maintained and ultraviolet exposure is limited. The study used remote-sensing data and illumination modeling. Illumination modeling estimates how long and how strongly sunlight shines on a location by calculating the moon's topography and the sun's position.
The researchers then examined whether bacteria and fungi such as Bacillus, Deinococcus, Staphylococcus, Aspergillus, and Fusarium could withstand the environmental conditions they identified. These microorganisms are relatively resistant to extreme environments and could be carried along in space exploration on spacecraft, equipment, or with people.
The analysis found that in some shaded and cold areas of the lunar polar regions, microorganisms may not die immediately and could survive. At the lunar poles, the sun sits low relative to the horizon, so even small hills or crater walls can cast long shadows.
Still, the team said, "A substantial portion of the lunar polar regions is likely to have surface conditions suitable for microbial survival," adding, "Even if microorganisms can endure in those environments, it would be difficult for them to grow or reproduce actively."
This study matters because upcoming crewed lunar exploration is primarily targeting the south pole. The lunar south pole contains permanently shadowed regions that receive little to no sunlight, where temperatures are so low that water molecules could persist as ice. Water ice could become a key resource, including for drinking water, in building future lunar bases.
NASA is aiming for the first crewed landing at the lunar south pole in 2028. Alongside that, it plans to investigate resources such as water ice and the lunar environment through robotic exploration and technology demonstrations, test landing and navigation technologies, and lay the groundwork needed for long-term lunar base construction.
As people and exploration equipment travel to and from the moon more frequently, the likelihood that Earth's microorganisms could unintentionally be transferred to the lunar surface also grows. That could cause confusion in distinguishing whether life-related materials or traces found on the moon originated there or were introduced from Earth.
The researchers emphasized, "Especially since near-term crewed lunar exploration will focus on the south polar region, it is important to identify in advance and manage the possibility that Earth's microorganisms could be transferred to the lunar surface during exploration."
References
Science Advances (2026), DOI: https://doi.org/10.1126/sciadv.aec0811