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Biogeochemical fingerprints of life: earlier analogies with polar ecosystems suggest feasible instrumentation for probing the Galilean moons

Published online by Cambridge University Press:  10 October 2014

J. Chela-Flores*
Affiliation:
Applied Physics Section, The Abdus Salam ICTP, Trieste, Italia IDEA, Instituto de Estudios Avanzados, Caracas, República Bolivariana de Venezuela
A. Cicuttin
Affiliation:
MLab, The Abdus Salam ICTP, Trieste, Italia
M.L. Crespo
Affiliation:
MLab, The Abdus Salam ICTP, Trieste, Italia
C. Tuniz
Affiliation:
MLab, The Abdus Salam ICTP, Trieste, Italia

Abstract

We base our search for the right instrumentation for detecting biosignatures on Europa on the analogy suggested by the recent work on polar ecosystems in the Canadian Arctic at Ellesmere Island. In that location sulphur patches (analogous to the Europan patches) are accumulating on glacial ice lying over saline springs rich in sulphate and sulphide. Their work reinforces earlier analogies in Antarctic ecosystems that are appropriate models for possible habitats that will be explored by the European Space Agency JUpiter ICy Moons Explorer (JUICE) mission to the Jovian System. Its Jupiter Ganymede Orbiter (JGO) will include orbits around Europa and Ganymede. The Galileo orbital mission discovered surficial patches of non-ice elements on Europa that were widespread and, in some cases possibly endogenous. This suggests the possibility that the observed chemical elements in the exoatmosphere may be from the subsurface ocean. Spatial resolution calculations of Cassidy and co-workers are available, suggesting that the atmospheric S content can be mapped by a neutral mass spectrometer, now included among the selected JUICE instruments. In some cases, large S-fractionations are due to microbial reduction and disproportionation (although sometimes providing a test for ecosystem fingerprints, even though with Sim – Bosak – Ono we maintain that microbial sulphate reduction large sulphur isotope fractionation does not require disproportionation. We address the question of the possible role of oxygen in the Europan ocean. Instrument issues are discussed for measuring stable S-isotope fractionations up to the known limits in natural populations of δ34 ≈ −70‰. We state the hypothesis of a Europa anaerobic oceanic population of sulphate reducers and disproportionators that would have the effect of fractionating the sulphate that reaches the low-albedo surficial regions. This hypothesis is compatible with the time-honoured expectation of Kaplan and co-workers (going back to the 1960s) that the distribution range of 32S/34S in analysed extra-terrestrial material appears to be narrower than the isotopic ratio of H, C or N and may be the most reliable for estimating biological effects. In addition, we discuss the necessary instruments that can test our biogenic hypothesis. First of all we hasten to clarify that the last-generation miniaturized mass spectrometer we discuss in the present paper are capable of reaching the required accuracy of ‰ for the all-important measurements with JGO of the thin atmospheres of the icy satellites. To implement the measurements, we single out miniature laser ablation time-of-flight mass spectrometers that are ideal for the forthcoming JUICE probing of the exoatmospheres, ionospheres and, indirectly, surficial low-albedo regions. Ganymede's surface, besides having ancient dark terrains covering about one-third of the total surface, has bright terrains of more recent origin, possibly due to some internal processes, not excluding biological ones. The geochemical test could identify bioindicators on Europa and exclude them on its large neighbour by probing relatively recent bright terrains on Ganymede's Polar Regions.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2014 

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References

Abplanalp, D., Wurz, P., Huber, L., Leya, I., Kopp, E., Rohner, U., Wieser, M., Kalla, L. & Barabash, S. (2009). A neutral gas mass spectrometer to measure the chemical composition of the stratosphere. Adv. Space Res. 44, 870878.Google Scholar
Barabash, S., Wurz, P. and the PEP team (2013). Particle Environment Package (PEP) for the ESA JUICE mission. In Geophysical Research Abstracts Vol. 15, EGU2013-9745, 2013 EGU General Assembly.Google Scholar
Briois, C. et al. (2013). Dust orbitrap sensor (DOTS) for in-situ analysis of airless planetary bodies. In 44th Lunar and Planetary Science Conf. 44(2013). http://www.lpi.usra.edu/meetings/lpsc2013/pdf/2888.pdf Google Scholar
Brunner, B., Bernasconi, S.M., Kleikemper, J. & Schroth, M.H. (2005). A model for oxygen and sulfur isotope fractionation in sulfate during bacterial sulfate reduction processes. Geochim. Cosmochim. Acta 69, 47734785.Google Scholar
Canfield, D.E. & Raiswell, R. (1999). The evolution of the sulfur cycle. Am. J. Sci. 299, 697723.CrossRefGoogle Scholar
Canfield, D. & Thamdrup, B. (1994). The production of 34S-depleted sulfide during bacterial disproprtionation of elemental sulfur. Science 266, 19731975.CrossRefGoogle ScholarPubMed
Carlson, R.W., Johnson, R.E. & Anderson, M.S. (1999). Sulfuric acid on Europa and the radiolytic sulfur cycle. Science 286, 9799.CrossRefGoogle ScholarPubMed
Cassidy, T.A., Johnson, R.E. & Tucker, O.J. (2009). Trace constituents of Europa's atmosphere. Icarus 201, 182190.CrossRefGoogle Scholar
Chela-Flores, J. (2010). Instrumentation for the search of habitable ecosystems in the future exploration of Europa and Ganymede. Int. J. Astrobiol. 9, 101108. http://www.ictp.it/~chelaf/jcf_IJA_2010.pdf Google Scholar
Chela-Flores, J. & Kumar, N. (2008). Returning to Europa: can traces of surficial life be detected? Int. J. Astrobiol. 7, 263269. http://www.ictp.it/~chelaf/JCFKumar.pdf CrossRefGoogle Scholar
Chyba, C. & Sagan, C. (1992). Endogenous production, exogenous delivery and impact-shock synthesis of organic molecules: an inventory for the origins of life. Nature 355, 125132.CrossRefGoogle ScholarPubMed
Detmers, J., Bruanchert, V., Habich, K.S. & Kuever, J. (2001). Diversity of sulfur isotope fractionations by sulfate-reducing prokaryotes. Appl. Environ. Microbiol. 67, 888894.Google Scholar
Fanale, F.P. et al. (1999). Galileo's multiinstrument spectral view of Europa's surface composition. Icarus 139, 179188.Google Scholar
Fanale, F.P. et al. (2000). Tyre and Pwyll: Galileo orbital remote sensing of mineralogy versus morphology at two selected sites on Europa. J. Geophys. Res. 105, 22,64722,655.Google Scholar
Fanale, F.P., Li, Y.-H., De Carlo, E., Farley, C., Sharma, S.K., Horton, K. & Granahan, J.C. (2001). An experimental estimate of Europa's “ocean” composition independent of Galileo orbital remote sensing. J. Geophys. Res. 106, 14,59514,600.Google Scholar
Farquhar, J., Johnston, D.T., Wing, B.A., Habicht, K.S., Canfield, D.E., Airieau, S. & Thiemens, M.H. (2003). Multiple sulphur isotopic interpretations of biosynthetic pathways: implications for biological signatures in the sulphur isotope record. Geobiology 1, 2736.Google Scholar
Fisher, T.M. & Schulze-Makuch, D. (2013). Nutrient and population dynamics in a subglacial reservoir: a simulation case study of the Blood Falls ecosystem with implications for astrobiology. Int. J. Astrobiol. 12, 304311.Google Scholar
Franz, H.B., Danielache, S.O., Farquhar, J. & Wing, B.A. (2013). Mass-independent fractionation of sulfur isotopes during broadband SO2 photolysis: comparison between 16O- and 18O-rich SO2 . Chem. Geo. 362, 5665.Google Scholar
Gaeman, J., Hier-Majumdera, S. & Roberts, J.H. (2012). Sustainability of a subsurface ocean within Triton's interior. Icarus 220, 339347.CrossRefGoogle Scholar
Gleeson, D.F., Pappalardo, R.T., Anderson, M.S., Grasby, S.E., Mielke, R.E., Wright, K.E. & Templeton, A.S. (2012). Biosignature detection at an Arctic analog to Europa. Astrobiology 12, 116.Google Scholar
Grasset, O., Bunce, E.J., Coustenis, A., Dougherty, M.K., Erd, C., Hussmann, H., Jaumann, R. & Prieto-Ballesteros, O. (2013a). Review of exchange processes on ganymede in view of its planetary protection categorization. Astrobiology 13(10), 9911004.Google Scholar
Grasset, O. et al. (2013b). JUpiter ICy moons Explorer (JUICE): an ESA mission to orbit Ganymede and to characterise the Jupiter system. Planet. Space Sci. 78, 121. doi: 10.1016/j.pss.2012.12.002.Google Scholar
Greely, R. (2013). Introduction to Planetary Morphology. Cambridge University Press, Cambridge, UK, pp. 162170.CrossRefGoogle Scholar
Greenberg, R. (2005). Europa, the Ocean Moon. Springer, Berlin.Google Scholar
Greenberg, R. (2009). Vertical Transport through Europa's Crust: Implications for Oxidant Delivery and Habitability. American Astronomical Society, DPS meeting #41, #66.08. http://adsabs.harvard.edu/abs/2009DPS....41.6608G Google Scholar
Grice, K., Cao, C., Love, G.D., Böttcher, M.E., Twitchett, R.J., Grosjean, E., Summons, R.E., Turgeon, S.C., Dunning, W. & Yugan, J. (2005). Photic zone euxinia during the permian-triassic superanoxic event. Science 307, 706709.Google Scholar
Hall, D.T., Strobel, D.F., Feldman, P.D., McGrath, M.A. & Weaver, H.A. (1995). Detection of an oxygen atmosphere on Jupiter's moon Europa. Nature 373, 677681.Google Scholar
Hand, K.P., Carlson, R.W. & Chyba, C.F. (2007). Energy, chemical disequilibrium, and geological constraints on Europa. Astrobiology 7, 10061022.Google Scholar
Hoefs, J. (2009). Stable Isotope Geochemistry, 6th edn. Springer–Verlag, Berlin. 285 pp.Google Scholar
Johnson, R.E., Killen, R.M., Waite, J.H. Jr. & Lewis, W.S. (1998). Europa's surface composition and sputter-produced ionosphere. Geophys. Res. Lett. 25, 32573260.Google Scholar
Johnson, R.E., Burger, M.H., Cassidy, T.A., Leblanc, F., Marconi, M. & Smyth, W.H. (2009). Composition and detection of Europa's sputter-induced atmosphere. In Europa, ed. Pappalardo, R.T., McKinnon, W.B. & Khurana, K.K., pp. 507527. University of Arizona Press. Tucson, AZ, USA.Google Scholar
Johnston, D.T. (2011). Multiple sulfur isotopes and the evolution of Earth's surface sulfur cycle. Earth Sci. Rev. 106, 161183.Google Scholar
Kaplan, I.R. (1975). Stable isotopes as a guide to biogeochemical processes. Proc. R. Soc. Lond. B 189, 183211 (cf. pp. 202–205).Google Scholar
Kaplan, I.R. & Rittenberg, S.C. (1964). Microbiological fractionation of sulphur isotopes. Microbiology 34, 195212.Google Scholar
Kargel, J.S., Kaye, J.Z., Head, J.W., Marion, G.M., Sassen, R., Crow-ley, J.K., Ballesteros, O.P., Grant, S.A. & Hogenboom, D.A. (2000). Europa's crust and ocean: origin, composition, and the prospects for life. Icarus 148, 226265.Google Scholar
Kivelson, M.G., Khurana, K.K., Russell, C.T., Volwerk, M., Walker, R.J. & Zimmer, C. (2000). Galileo magnetometer measurements: a stronger case for a subsurface ocean at Europa. Science 289, 13401343.Google Scholar
Knoll, A.H., Canfield, D.E. & Konhauser, K.O. (2012). What is Geobiology? In Fundamentals of Geobiology, 1st edn, ed. Knoll, A.H., Canfield, D.E. & Konhauser, K.O., pp. 14. Blackwell Publishing Ltd. Chichester, UK.Google Scholar
Kiyosu, Y. & Krouse, H.R. (1990). The role of organic acid in the abiogenic reduction of sulfate and the sulfur isotope effect. Geochem. J. 24, 2127.Google Scholar
Krouse, H.R., Viau, C.A., Eliuk, L.S., Ueda, A. & Halas, S. (1988). Chemical and isotopic evidence of thermochemical sulfate reductionby light-hydrocarbon gases in deep carbonate reservoirs. Nature 333, 415419.Google Scholar
Leblanc, F., Johnson, R.E. & Brown, M.E. (2002). Europa's sodium atmosphere: an ocean source? Icarus 159, 132144. doi: 10.1006/icar.2002.6934.Google Scholar
Lipps, J.H. et al. (2004). Astrobiology of Jupiter's Icy Moons. Proc. SPIE 5555, 10. doi: 10.1117/12.560356.Google Scholar
Lorenz, R.D., Gleeson, D., Prieto-Ballesteros, O., Gomez, F., Hand, K. & Bulat, S. (2011). Analog environments for a Europa lander mission. Adv. Space Res. 48, 689696.Google Scholar
Machel, H.G., Krouse, H.R. & Sassen, R. (1995). Products and distinguishing criteria of bacterial and thermochemical sulfate reduction. Appl. Geochem. 10, 373389.Google Scholar
McCord, T.B. et al. (1999). Hydrated minerals on Europa's surface from the Galileo near-infrared mapping spectrometer (NIMS) investigation. J. Geophys. Res. 104, 11,82711,851. 10.1007/s11214-012-9912-2.Google Scholar
McCord, T.B., Hansen, G.B. & Hibbitts, C.A. (2001). Hydrated salts on Ganymede's surface: evidence for an ocean below. Science 292, 15231525.Google Scholar
McCord, T.B., Teeter, G., Hansen, G.B., Sieger, M.T. & Orlando, T.M. (2002). Brines exposed to Europa surface conditions. J. Geophys. Res. 107(E1), 5004, doi: 10.1029/2000JE001453.Google Scholar
McKay, C.P., Anbar, A.D., Porco, C. & Tsou, P. (2014). Follow the plume: the habitability of enceladus. Astrobiology 14, 352355.Google Scholar
Mikucki, J.A., Pearson, A., Johnston, D.T., Turchyn, A.V., Farquhar, J., Schrag, D.P., Anbar, A.D., Priscu, J.C. & Lee, P.A. (2009). A contemporary microbially maintained subglacial ferrous ‘ocean. Science 324, 397398.Google Scholar
Miljković, K. (2011). Europa: orbital surface sampling without landing. J. Cosmol. 13, 37763789.Google Scholar
Miljković, K., Hillier, J.K., Mason, N.J. & Zarnecki, J.C. (2012). The models of dust around Europa and Ganymede. Planet. Space Sci. 70, 2027.Google Scholar
Moorbath, S. (1994). Age of the oldest rocks with biogenic components. J. Biol. Phys. 20, 8594.Google Scholar
Pappalardo, R.T. et al. (2013). Science potential from a Europa Lander. Astrobiology 13, 740773.Google Scholar
Prockter, L.M. & Schenk, P. (2005). Origin and evolution of Castalia Macula, an anomalous young depression on Europa. Icarus 177, 305326.Google Scholar
Rees, C.E. (1973). A steady-state model for sulphur isotope fractionation in bacterial reduction processes. Geochim. Cosmochim. Acta 37, 11411162.Google Scholar
Riedo, A., Meyer, S., Heredia, B., Neuland, M., Bieler, A., Tulej, M., Leya, Iakovleva M., Mezger, K. & Wurz, P. (2012). Highly accurate isotope composition measurements by a miniature laser ablation mass spectrometer designed for in situ investigations on planetary surfaces. Planet. Space Sci. 87, 113.CrossRefGoogle Scholar
Riedo, A., Bieler, A., Neuland, M., Tulej, M. & Wurz, P. (2013a). Performance evaluation of a miniature laser ablation time-of-flight mass spectrometer designed for in situ investigations in planetary space research. J. Mass. Spectrom. 48, 115. doi: 10.1002/jms.3157 CrossRefGoogle ScholarPubMed
Riedo, A., Neuland, M., Meyer, S., Tulej, M. & Wurz, P. (2013b). Coupling of LMS with fs-laser ablation ion source: elemental and isotope composition measurements. J. Anal. Atom. Spectrom. 28, 12561269. doi: 10.1039/C3JA50117E.Google Scholar
Schenk, P.M., McKinnon, W.B., Gwynn, D. & Moore, J.M. (2010). Flooding of Ganymede's bright terrains by low-viscosity water-ice lavas. Nature 410, 5760.Google Scholar
Schildowski, M. (1988). A 3800-million year isotopic record of life from carbon in sedimentary rocks. Nature 333, 313318.Google Scholar
Shirley, J., Dalton, J. III, Prockter, L. & Kamp, L. (2010). Europa's ridged plains and smooth low albedo plains: distinctive compositions and compositional gradients at the leading side, trailing side boundary. Icarus 210, 358384.Google Scholar
Sim, M.S., Bosak, T. & Ono, S. (2011). Large sulfur isotope fractionation does not require disproportionation. Science 333, 7477.Google Scholar
Spohn, T. & Schubert, G. (2003). Oceans in the icy Galilean satellites of Jupiter? Icarus 161(2), 456467.Google Scholar
Smith, J.W. (2000). Isotopic fractionations accompanying sulfur hydrolysis. Geochem. J. 34, 9599.Google Scholar
Thamdrup, B. (2007). New players in an ancient cycle. Science 317, 15081509.Google Scholar
Turrini, D. et al. (2014). The ODINUS Mission Concept – The Scientific Case for a Mission to the Ice Giant Planets with Twin Spacecraft to Unveil the History of our Solar System. arXiv:1402.2472 [astro-ph.EP].Google Scholar
Vance, S., Bouffard, M., Choukroun, M. & Sotina, C. (2014). Ganymede's internal structure including thermodynamics of magnesium sulfate oceans in contact with ice. Planet. Space Sci. 96, 6270.Google Scholar
Wortmann, U.G., Bernasconi, S.M. & Bottcher, M.E. (2001). Hypersulfidic deep biosphere indicates extreme sulfur isotope fractionation during single-step microbial sulfate reduction. Geology 29, 647650.Google Scholar
Wurz, P., Abplanalp, D. Tulej, M. & Lammer, H. (2012). A neutral gas mass spectrometer for the investigation of lunar volatiles. Planet. Space Sci. 74, 264269.Google Scholar
Zahnle, K., Schenk, P., Levison, H. & Dones, L. (2003). Cratering rates in the outer Solar System. Icarus 163, 263289.Google Scholar
Zolotov, M.Yu. & Shock, E.L. (2001). Composition and stability of salts on the surface of Europa and their oceanic origin. J. Geophys. Res., [Planets] 106, 3281532828.Google Scholar
Zolotov, M.Y. & Shock, E.L. (2004). A model for low-temperature biogeochemistry of sulfur, carbon, and iron on Europa. J. Geophys. Res., [Planets] 109, E06003 (16 pp.), doi: 10.1029/2003JE002194.CrossRefGoogle Scholar