Paleo-Rock-Hosted Life on Earth and the Search on Mars: A Review and Strategy for Exploration

Autor: Paul B. Niles, Haley M. Sapers, Bethany L. Ehlmann, Anna Neubeck, Jeffrey J. Marlow, Max Coleman, Tullis C. Onstott, Magnus Ivarsson
Rok vydání: 2019
Předmět:
Geologic Sediments
Microbial diversity
Extraterrestrial Environment
010504 meteorology & atmospheric sciences
Groundwater flow
Earth
Planet

Earth science
FOS: Physical sciences
Subsurface life
Mars
Annan geovetenskap och miljövetenskap
Geologic record
Life on Mars
Exploration of Mars
01 natural sciences
Search for life
Martian surface
Exobiology
0103 physical sciences
Geosciences
Multidisciplinary

Review Articles
010303 astronomy & astrophysics
0105 earth and related environmental sciences
Earth and Planetary Astrophysics (astro-ph.EP)
Martian
Total organic carbon
Paleontology
Mars Exploration Program
Multidisciplinär geovetenskap
Agricultural and Biological Sciences (miscellaneous)
Space and Planetary Science
Biosignatures
Geology
Astrophysics - Earth and Planetary Astrophysics
Other Earth and Related Environmental Sciences
Zdroj: Onstott, T C, Ehlmann, B L, Sapers, H, Coleman, M, Ivarsson, M, Marlow, J J, Neubeck, A & Niles, P 2019, ' Paleo-Rock-Hosted Life on Earth and the Search on Mars : A Review and Strategy for Exploration ', Astrobiology, vol. 19, no. 10, pp. 1230-1262 . https://doi.org/10.1089/ast.2018.1960
Astrobiology
ISSN: 1557-8070
1531-1074
Popis: We review the abundance and diversity of terrestrial rock hosted life, the environments it inhabits, the evolution of its metabolisms, and its fossil biomarkers to provide guidance in the search for the biomarkers of rock hosted life on Mars. Key finds are metabolic pathways for chemolithotrophic microorganisms evolved much earlier in Earth history than those of surface dwelling phototrophic microorganisms,the emergence of the former occurred at a time when Mars was habitable, whereas that of the latter occurred at a time when the martian surface would have been uninhabitable, subsurface biomass do not correlate with organic carbon and tends to be highest at interfaces where chemical redox gradients are most pronounced, deep subsurface metabolic activity does not rely upon the respiration of organic photosynthate but upon the flux of inorganic energy and the abiotic and biotic recycling of metabolic waste products, and the rock record reveals examples of subsurface life back to 3.45 Ga with several examples of good preservation potential in rock types that are quite different from those preserving the photospheric supported biosphere.These findings suggest that rock hosted life would have likely to emerge and be preserved in a martian context. We thus propose a Mars exploration strategy that scales spatially, focusing initially on identifying rocks with evidence for groundwater flow and low temperature mineralization, then identifying redox and permeability interfaces preserved within rock outcrops, and finally focusing on finding minerals associated with redox reactions and traces of carbon and diagnostic biosignatures. The lessons from Earth show that ancient rock hosted life is preserved in the fossil record and confirmable via a suite of morphologic, organic, mineralogical and isotopic fingerprints and microscopic textures.
55 pages, 5 figures, 2 tables
Databáze: OpenAIRE