Survival of soil microbial community exposed to hyper-gravity conditions

Abstract Earth is the cradle of mankind, but it is impossible for human beings to live in the cradle forever. Sending soil microbial spores through space to foreign planets will be a likely initial process in planet colonization. Periods of hyper-gravity are likely to be a challenge for the candidate microorganisms during their interstellar transportation, raising questions about their survival rates and community-level responses. To address these questions, the impacts of hyper-gravity on soil microbial community composition and activity were tested by applying 1×g or 2500×g centrifugal force to soil for 6 days. The results indicated an increased diversity and absolute abundance of soil total bacterial community and a relatively stable active bacterial community under hyper-gravity condition. Besides, hyper-gravity had no observable effect on the relative abundance of soil microorganisms. These results suggest that soil microorganisms could survive during short periods of hyper-gravity. Our findings represent the first step towards a better understanding of the potential for survival of soil microbiomes during space travel and provide a basis for further interstellar soil research.