Mars polar cap: a habitat for elementary life

• Published in: International Journal of Astrobiology
• Main Authors: Wallis, M.K., Wickramasinghe, J.T., Wickramasinghe, N.C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2009
• Subjects: Earth and Planetary Sciences (miscellaneous); Space and Planetary Science; Physics and Astronomy (miscellaneous); Ecology, Evolution, Behavior and Systematics; Antarctic; The Antarctic; Antarc*; Ice; permafrost
• Online Access: http://dx.doi.org/10.1017/s1473550409004467; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1473550409004467

Abstract Ices in the Martian polar caps are potential habitats for various species of microorganisms. Salts in the ice and biological anti-freeze polymers maintain liquid in cracks in the ices far below 0°C, possibly down to the mean 220–240 K. Sub-surface microbial life is shielded from ultraviolet (UV) radiation, but could potentially be activated on south-facing slopes under the midday, midsummer Sun. Such life would be limited by low levels of vapour, little transport of nutrients, low light levels below a protective dirt-crust, frost accumulation at night and in shadows, and little if any active translocation of organisms. As in the Antarctic and in permafrost, movement to new habitats depends on geo-climatic changes, which for Mars's north polar cap occur on a 50 000 year scale, except for rare meteorite impacts.