20-EPN-28: 20-EPN-28: Microbial adaptation in the hypersaline environment of Sua Pan Evaporator Ponds in Botswana and implications for search for life on Mars

Visit by Claudia Pacelli, Italian Space Agency (Italy) and Alessia Cassaro, University of Tuscia (Italy) to TA1.5 Makgadikgadi Salt Pans (Botswana).
Dates of visit: 12-21 July 2022

The current conditions of the Martian surface are considered prohibitive for life as we know it, due to strong radiation, highly oxidizing conditions, concentrated evaporative salts, and relatively low water activity. The Earth hosts a multitude of extreme environments whose physico-chemical properties partly match extraterrestrial planetary bodies (e.g. Mars). Such environments are defined “analogue sites” and may offer critical test-bed for astrobiological studies in characterising the physical and chemical boundaries within which life may exist on Earth and in assessing the habitability of other planets, understanding the biological mechanisms for survival in extreme environments.
For example, the Makgadikgadi desert, located in north central Botswana is considered one
of the largest deserts on Earth, where the salts concentration is up to 21% of NaCl. These
conditions may be compared with those detected on Mars.

Here, the main aim of this Europlanet project was to collect soil samples of Makgadikgadi salt pans in order to i) understand the adaptations of microbial systems to extreme conditions in natural terrestrial environments, ii) correlate the biodiversity with the geological context. This study is of significant interest to astrobiology investigations, allowing to assess the effects of hypersaline environment on the survival potential of microorganism and to understand if hypothetical life-forms may exist or have existed on Mars, where the concentration of chlorate salts has been detected in many different locations, from 1970s.

Report Summary:

Read the full report, published with kind permission by Dr Pacelli and Dr Cassaro.

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