Earth Microbes Found on Asteroid Ryugu Sample After Return to Earth

Terrestrial bacteria rapidly colonized a pristine asteroid sample, raising concerns about contamination in extraterrestrial research.

Researchers discovered terrestrial microbes on a Ryugu asteroid sample returned by Japan's Hayabusa2 mission in 2020.
The microbes were not present during initial analysis but appeared and multiplied after exposure to Earth's atmosphere.
Despite stringent contamination controls, including hermetically sealed transport and nitrogen-purged clean rooms, bacteria colonized the sample within a week.
The findings highlight the resilience of Earth's microorganisms and the challenges of maintaining uncontaminated extraterrestrial samples.
Experts stress the need for stricter planetary protection protocols to ensure the integrity of future space missions and avoid misidentifying Earth-origin microbes as alien life.