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Astrobiology and habitability studies in preparation for future Mars missions: trends from investigating minerals, organics and biota

Published online by Cambridge University Press:  12 May 2011

P. Ehrenfreund ,
W.F.M. Röling ,
C.S. Thiel ,
R. Quinn ,
M.A. Sephton ,
C. Stoker ,
J.M. Kotler ,
S.O.L. Direito ,
Z. Martins  and
G.E. Orzechowska
...Show all authors
P. Ehrenfreund*
Affiliation:
Leiden Institute of Chemistry, PO Box 9502, 2300 Leiden, The Netherlands Space Policy Institute, Elliott School of International Affairs, Washington, DC, USA
W.F.M. Röling
Affiliation:
Faculty of Earth and Life Sciences, VU University Amsterdam, Amsterdam, The Netherlands
C.S. Thiel
Affiliation:
Institute of Medical Physics and Biophysics, CeNTech, University of Münster, 48149, Münster, Germany
R. Quinn
Affiliation:
NASA Ames Research Center, Moffett Field, CA 94035, USA
M.A. Sephton
Affiliation:
Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
C. Stoker
Affiliation:
NASA Ames Research Center, Moffett Field, CA 94035, USA
J.M. Kotler
Affiliation:
Leiden Institute of Chemistry, PO Box 9502, 2300 Leiden, The Netherlands
S.O.L. Direito
Affiliation:
Faculty of Earth and Life Sciences, VU University Amsterdam, Amsterdam, The Netherlands
Z. Martins
Affiliation:
Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
G.E. Orzechowska
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
R.D. Kidd
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
C.A van Sluis
Affiliation:
Department of Biotechnology, Delft University of Technology, 2628 BC Delft, The Netherlands
B.H. Foing
Affiliation:
ESA ESTEC, Postbus 299, 2200 AG Noordwijk, The Netherlands
*
e-mail: p.ehrenfreund@chem.leidenuniv.nl
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Abstract

Several robotic exploration missions will travel to Mars during this decade to investigate habitability and the possible presence of life. Field research at Mars analogue sites such as desert environments can provide important constraints for instrument calibration, landing site strategies and expected life detection targets. We have characterized the mineralogy, organic chemistry and microbiology of ten selected sample sites from the Utah desert in close vicinity to the Mars Desert Research Station (MDRS) during the EuroGeoMars 2009 campaign (organized by International Lunar Exploration Working Group (ILEWG), NASA Ames and ESA ESTEC). Compared with extremely arid deserts (such as the Atacama), organic and biological materials can be identified in a larger number of samples and subsequently be used to perform correlation studies. Among the important findings of this field research campaign are the diversity in the mineralogical composition of soil samples even when collected in close proximity, the low abundances of detectable polycyclic aromatic hydrocarbons (PAHs) and amino acids and the presence of biota of all three domains of life with significant heterogeneity. An extraordinary variety of putative extremophiles, mainly Bacteria and also Archaea and Eukarya was observed. The dominant factor in measurable bacterial abundance seems to be soil porosity and lower small (clay-sized) particle content. However, correlations between many measured parameters are difficult to establish. Field research conducted during the EuroGeoMars 2009 campaign shows that the geological history and depositional environment of the region, as well as the mineralogy influence the ability to detect compounds such as amino acids and DNA. Clays are known to strongly absorb and bind organic molecules often preventing extraction by even sophisticated laboratory methods. Our results indicate the need for further development and optimization of extraction procedures that release biological compounds from host matrices to enable the effective detection of biomarkers during future sampling campaigns on Earth and Mars.

Keywords

astrobiologyhabitabilitylife detectionfield analogue researchMarsorganicsclayslanding site criteria
Type
Research Article
Information
International Journal of Astrobiology , Volume 10 , Special Issue 3: Special issue: Astrobiology field research in Moon/Mars analogue environments , July 2011 , pp. 239 - 253
Copyright
Copyright © Cambridge University Press 2011

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