Sustainability of Extreme Microbial Ecosystems to the Comprehensive Impact of Physical Factors of the Martian Regolith

Abstract

As the key parameters of the Martian regolith, we have studied the combined effect of gamma radiation (1 and 10 kGy), low temperature (–50°C), and low pressure (1 Torr) on the microbial communities of extreme ecotopes of Earth to estimate the duration of cryopreservation of hypothetical Martian ecosystems in a viable state. The obtained data suggest that cryopreservation of viable microorganisms in the surface layer of the regolith is possible for at least 130000 years; at a depth of 30 cm, for 170000 years; at a depth of 2 m (the depth which the ExoMars 2020 mission must reach), for 330000 years; and at a depth of 5 m, for 2 million years.