Perchlorate‐tolerant bacterial strains isolated from the Mars‐analog Qaidam Basin soils exposed to Earth's near space

Impact statement Earth's lower near space of 20–40 km above sea level with polyextreme conditions serves as a unique Mars analog for astrobiological research to investigate the limits of life on Earth and planetary protection considerations for Mars exploration. In this study, we exposed Mars‐like desert regolith to near space at a float altitude of ~35 km and isolated four bacterial strains after exposure. In addition to stress tolerance to extreme environmental stressors, these strains represent a remarkable tolerance to perchlorate that is widespread in present‐day Martian soils. These extremophilic bacterial strains screened through near‐space exposure could serve as promising candidates for future astrobiological research in space stations or in laboratory‐based planetary simulation environments.