Microbial survival in extreme cold impacts lunar exploration

Microorganisms exhibit significant resilience to extreme cold, a factor with implications for both Earth-based science and space exploration. On Earth, psychrophiles and psychrotolerant bacteria thrive in environments such as glaciers, permafrost, and polar oceans. These organisms utilize specialized evolutionary strategies to maintain metabolic processes even at temperatures below −15 °C, often utilizing liquid water found in microscopic ice fissures.

This biological capability poses unique challenges for lunar exploration, particularly regarding the Moon's south pole. The permanently shadowed regions of the lunar south pole act as a natural planetary freezer. While radiation and vacuum are primary threats in space, the extreme cold and lack of environmental movement in these craters may allow terrestrial microbes carried by human missions to survive in an inactive state. This potential for biological contamination is a critical consideration for future lunar missions and the preservation of space environments.