As NASA prepares for human missions to the lunar surface, a new study published in Science Advances warns that astronauts may inadvertently transport Earth-based bacteria and fungi to the Moon. Because microbes naturally inhabit the human body and can easily leak from habitats or spacesuits, researchers are concerned that these tiny organisms could contaminate lunar environments. While most of the Moon is too harsh for life to endure, the study identifies shaded regions near the South Pole—ranging from large craters to areas as small as a boot print—that might provide enough protection for these microbes to survive in a dormant state.

This discovery poses a significant challenge for scientists who are striving to understand the Moon's natural history. If Earth-based microbes take hold, it becomes increasingly difficult to distinguish between indigenous lunar materials and human-introduced contaminants. Beyond lunar exploration, NASA views this research as a critical step in preparing for future missions to Mars. By understanding how life might persist in extreme environments, space agencies can better protect the integrity of extraterrestrial research and ensure that our search for alien life remains accurate and untainted.