Other Analogs to Mars: High Altitude, Subsurface, Desert, and Polar Environments

Abstract

The McMurdo Dry Valleys detailed in previous chapters represent one environment for life thought to have existed on Mars among many. This chapter illustrates other potential habitats and their significance: (1) high-altitude lakes subjected to rapid climate change in the Andes provide analogy to the Noachian/Hesperian transition on Mars; (2) Río Tinto, Spain, where conditions are reminiscent of Meridiani Planum, unravels an underground anaerobic chemoautotroph biosphere that could resemble a modern refuge for life on Mars; (3) the High Arctic hosts gullies analogous to those observed on Mars, whose fresh deposits could provide access to traces of past and/or present underground oases; it is also in this polar environment that the Haughton-Mars Project helps answer long-standing questions, revisiting classical assumptions, and sometimes reshaping our thinking on many issues in planetary science and astrobiology, in particular in relation to Mars; (4) the search for microbial life in the arid soils of the Atacama desert and its robotic detection characterize what role aridity plays in the distribution of life and how to search for evidence of rare and scattered biosignatures.