Wind-Driven Saltation:An Overlooked Challenge for Life on Mars
| Autor: | M G Larsen, Ebbe Bak, Svend J. Knak Jensen, Per Nørnberg, Ralf Moeller, Kai Finster |
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| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Spores
010504 meteorology & atmospheric sciences Saltation Habitability OXIDANT ENHANCEMENT Microorganisms Life on Mars 01 natural sciences SPACECRAFT SURFACES Astrobiology Wind driven HYDROGEN-PEROXIDE Martian surface Saltation (geology) 0103 physical sciences Mineral particles 010303 astronomy & astrophysics 0105 earth and related environmental sciences Martian DEINOCOCCUS-RADIODURANS fungi UV-RADIATION MARTIAN DUST DEVILS Agricultural and Biological Sciences (miscellaneous) Regolith BACILLUS-SUBTILIS SPORES ASSEMBLY CLEAN ROOMS Space and Planetary Science Erosion IONIZING-RADIATION Forward contamination RESISTANCE |
| Zdroj: | Bak, E N, Larsen, M G, Jensen, S K, Nornberg, P, Moeller, R & Finster, K 2019, ' Wind-Driven Saltation : An Overlooked Challenge for Life on Mars ', Astrobiology, vol. 19, no. 4 . https://doi.org/10.1089/ast.2018.1856 |
| Popis: | Numerous studies have demonstrated that the martian surface environment is hostile to life because of its rough radiation climate and the reactive chemistry of the regolith. Physical processes such as erosion and transport of mineral particles by wind-driven saltation have hitherto not been considered as a life hazard. We report a series of experiments where bacterial endospores (spores of Bacillus subtilis) were exposed to a simulated saltating martian environment. We observed that 50% of the spores that are known to be highly resistant to radiation and oxidizing chemicals were destroyed by saltation-mediated abrasion within one minute. Scanning electron micrographs show that the spores were not only damaged by abrasion but were eradicated during the saltation process. We suggest that abrasion mediated by wind-driven saltation should be included as a factor that defines the habitability of the martian surface environment. The process may efficiently protect the martian surface from forward contamination with terrestrial microbial life-forms. Abrasion mediated by wind-driven saltation should also be considered as a major challenge to indigenous martian surface life if it exists/existed. |
| Databáze: | OpenAIRE |
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