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Abstract
To assess Mars’ potential for both harboring life and providing useable resources for future human exploration, it is of paramount importance to comprehend the water situation on the planet. Therefore, studies have been conducted to determine any evidence of past or present water existence on Mars. While the presence of abundant water on Mars very early in its history is widely accepted, on its modern form, only a fraction of this water can be found, as either ice or locked into the structure of Mars’ plentiful water-rich materials. Water on the planet is evaluated through various evidence such as rocks and minerals, Martian achondrites, low volume transient briny outflows (e.g., dune flows, reactivated gullies, slope streaks, etc.), diurnal shallow soil moisture (e.g., measurements by Curiosity and Phoenix Lander), geomorphic representation (possibly from lakes and river valleys), and groundwater, along with further evidence obtained by probe and rover discoveries. One of the most significant lines of evidence is for an ancient streambed in Gale Crater, implying ancient amounts of “vigorous” water on Mars. Long ago, hospitable conditions for microbial life existed on the surface of Mars, as it was likely periodically wet. However, its current dry surface makes it almost impossible as an appropriate environment for living organisms; therefore, scientists have recognized the planet’s subsurface environments as the best potential locations for exploring life on Mars. As a result, modern research has aimed towards discovering underground water, leading to the discovery of a large amount of underground ice in 2016 by NASA, and a subglacial lake in 2018 by Italian scientists. Nevertheless, the presence of life in Mars’ history is still an open question. In this unifying context, the current review summarizes results from a wide variety of studies and reports related to the history of water on Mars, as well as any related discussions on the possibility of living organism existence on the planet.
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Salese F, McMahon WJ, Balme MR, Ansan V, Davis JM, Kleinhans MG. Sustained fluvial deposition recorded in Mars' Noachian stratigraphic record. Nat Commun 2020; 11:2067. [PMID: 32372029 PMCID: PMC7200759 DOI: 10.1038/s41467-020-15622-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 03/16/2020] [Indexed: 11/09/2022] Open
Abstract
Orbital observation has revealed a rich record of fluvial landforms on Mars, with much of this record dating 3.6–3.0 Ga. Despite widespread geomorphic evidence, few analyses of Mars’ alluvial sedimentary-stratigraphic record exist, with detailed studies of alluvium largely limited to smaller sand-bodies amenable to study in-situ by rovers. These typically metre-scale outcrop dimensions have prevented interpretation of larger scale channel-morphology and long-term basin evolution, vital for understanding the past Martian climate. Here we give an interpretation of a large sedimentary succession at Izola mensa within the NW Hellas Basin rim. The succession comprises channel and barform packages which together demonstrate that river deposition was already well established >3.7 Ga. The deposits mirror terrestrial analogues subject to low-peak discharge variation, implying that river deposition at Izola was subject to sustained, potentially perennial, fluvial flow. Such conditions would require an environment capable of maintaining large volumes of water for extensive time-periods, necessitating a precipitation-driven hydrological cycle. Using high-resolution orbital imagery of the Martian surface, the authors Salese et al. here describe the first discovered stratigraphic product of multiple extensive fluvial-channel belts in an exposed vertical section at Izola Mensa in the northwestern rim of the Hellas Basin.
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Affiliation(s)
- Francesco Salese
- Faculty of Geosciences, Utrecht University, Princetonlaan 8a, Utrecht, 3584 CB, The Netherlands. .,International Research School of Planetary Sciences, Università Gabriele D'Annunzio, Viale Pindaro 42, Pescara, 65127, Italy.
| | - William J McMahon
- Faculty of Geosciences, Utrecht University, Princetonlaan 8a, Utrecht, 3584 CB, The Netherlands
| | - Matthew R Balme
- Planetary Environments Group, Open University, Walton Hall, Milton Keynes, UK
| | - Veronique Ansan
- LPG Nantes, UMR6112, CNRS-Université de Nantes, 2 rue de la Houssinère, BP 92208, 44322, Nantes Cedex 3, France
| | - Joel M Davis
- Department of Earth Sciences, Natural History Museum, Cromwell Road, Kensington, London, SW7 5BD, UK
| | - Maarten G Kleinhans
- Faculty of Geosciences, Utrecht University, Princetonlaan 8a, Utrecht, 3584 CB, The Netherlands
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Ende M, Kirkkala T, Loitzenbauer M, Talla D, Wildner M, Miletich R. High-Pressure Behavior of Nickel Sulfate Monohydrate: Isothermal Compressibility, Structural Polymorphism, and Transition Pathway. Inorg Chem 2020; 59:6255-6266. [PMID: 32293173 PMCID: PMC7201398 DOI: 10.1021/acs.inorgchem.0c00370] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Single crystals of
synthetic nickel sulfate monohydrate, α-NiSO4·H2O (space-group symmetry C2/c at ambient conditions), were subject to high-pressure behavior investigations
in a diamond-anvil cell up to 10.8 GPa. By means of subtle spectral
changes in Raman spectra recorded at 298 K on isothermal compression,
two discontinuities were identified at 2.47(1) and 6.5(5) GPa. Both
transitions turn out to be apparently second order in character, as
deduced from the continuous evolution of unit-cell volumes determined
from single-crystal X-ray diffraction. The first structural transition
from α- to β-NiSO4·H2O is an
obvious ferroelastic C2/c–P1̅ transition. It is purely displacive from a structural
point of view, accompanied by symmetry changes in the hydrogen-bonding
scheme. The second β- to γ-NiSO4·H2O transition, further splitting the O2 (hydrogen bridge acceptor)
position and violating the P1̅ space-group
symmetry, is also evident from the splitting of individual bands in
the Raman spectra. It can be attributed to symmetry reduction through
local violation of local centrosymmetry. Lattice elasticities were
obtained by fitting second-order Birch–Murnaghan equations
of state to the p-V data points
yielding the following zero-pressure bulk moduli values: K0 = 63.4 ± 1.0 GPa for α-NiSO4·H2O, K0 = 61.3 ± 1.9 GPa for
β-NiSO4·H2O, and K0 = 68.8 ± 2.5 GPa for γ-NiSO4·H2O. Synthetic nickel sulfate monohydrate
crystals (space group C2/c at ambient
conditions) were subject to in situ high-pressure solid-state investigations
(structure from single crystal X-ray diffraction, lattice parameter,
Raman spectra) in a diamond-anvil cell up to 10.8 GPa. Two discontinuities,
apparently phase transitions of second order, were identified at 2.47
± 0.01 (obvious ferroelastic C2/c−P1̅) and 6.5 ± 0.5 GPa (P1̅−P1̅). Birch−Murnaghan
equations of state were fitted to the P−V data, and the obtained parameters are given.
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Affiliation(s)
- Martin Ende
- Department of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Austria
| | - Terhi Kirkkala
- Department of Chemistry, University of Jyväskylä, Survontie 9 B, Ylistönrinne, FI-40014 Jyväskylä, Finland
| | - Michael Loitzenbauer
- Department of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Austria
| | - Dominik Talla
- Department of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Austria
| | - Manfred Wildner
- Department of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Austria
| | - Ronald Miletich
- Department of Mineralogy and Crystallography, University of Vienna, Althanstraße 14, A-1090 Wien, Austria
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Costello LJ, Filiberto J, Crandall JR, Potter-McIntyre SL, Schwenzer SP, Miller MA, Hummer DR, Olsson-Francis K, Perl S. Habitability of Hydrothermal Systems at Jezero and Gusev Craters as Constrained by Hydrothermal Alteration of a Terrestrial Mafic Dike. CHEMIE DER ERDE : BEITRAGE ZUR CHEMISCHEN MINERALOGIE, PETROGRAPHIE UND GEOLOGIE 2020; 80:125613. [PMID: 33299255 PMCID: PMC7720477 DOI: 10.1016/j.chemer.2020.125613] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
NASA's search for habitable environments has focused on alteration mineralogy of the Martian crust and the formation of hydrous minerals, because they reveal information about the fluid and environmental conditions from which they precipitated. Extensive work has focused on the formation of alteration minerals at low temperatures, with limited work investigating metamorphic or high-temperature alteration. We have investigated such a site as an analog for Mars: a mafic dike on the Colorado Plateau that was hydrothermally altered from contact with groundwater as it was emplaced in the porous and permeable Jurassic Entrada sandstone. Our results show evidence for fluid mobility removing Si and K but adding S, Fe, Ca, and possibly Mg to the system as alteration progresses. Mineralogically, all samples contain calcite, hematite, and kaolinite; with most samples containing minor anatase, barite, halite, and dolomite. The number of alteration minerals increase with alteration. The hydrothermal system that formed during interaction of the magma (heat source) and groundwater would have been a habitable environment once the system cooled below ~120° C. The mineral assemblage is similar to alteration minerals seen within the Martian crust from orbit, including those at Gusev and Jezero Craters. Therefore, based on our findings, and extrapolating them to the Martian crust, these sites may represent habitable environments which would call for further exploration and sample return of such hydrothermally altered igneous materials.
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Affiliation(s)
- Lacey J. Costello
- Southern Illinois University, Department of Geology, 1259 Lincoln Drive, Carbondale, IL 62901, USA
| | - Justin Filiberto
- Lunar and Planetary Institute, USRA, 3600 Bay Area Blvd., Houston, TX 77058, USA
| | - Jake R. Crandall
- Eastern Illinois University, Department of Geology and Geography, Physical Science Building, 600 Lincoln Ave., Charleston, IL 61920, USA
| | - Sally L. Potter-McIntyre
- Southern Illinois University, Department of Geology, 1259 Lincoln Drive, Carbondale, IL 62901, USA
| | - Susanne P. Schwenzer
- School of Environment, Earth, and Ecosystems Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - Michael A. Miller
- Materials Engineering Department, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238, USA
| | - Daniel R. Hummer
- Southern Illinois University, Department of Geology, 1259 Lincoln Drive, Carbondale, IL 62901, USA
| | - Karen Olsson-Francis
- School of Environment, Earth, and Ecosystems Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
| | - Scott Perl
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr, Pasadena, CA 91109-8001, USA
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55
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Sun VZ, Milliken RE. Characterizing the Mineral Assemblages of Hot Spring Environments and Applications to Mars Orbital Data. ASTROBIOLOGY 2020; 20:453-474. [PMID: 31545076 DOI: 10.1089/ast.2018.2003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Certain martian hydrated silica deposits have been hypothesized to represent ancient hot spring environments, but many environments can produce hydrated silica on Earth. This study compares the mineral assemblages produced in terrestrial hot springs to those observed in silica-producing volcanic fumarolic environments to determine which diagnostic features of hot springs could be remotely sensed on Mars. We find that hot spring environments are more likely to produce geochemically mature silica (i.e., opal-CT and microcrystalline quartz) in addition to opal-A, whereas volcanic fumarolic environments tend to produce only opal-A, potentially reflecting differences in water-to-rock ratios. Neutral/alkaline hot springs contain few accessory minerals (typically calcite and Fe/Mg clays), while acidic hot springs commonly contain accessory kaolinite. By comparison, mineral assemblages at volcanic fumaroles contain protolith igneous minerals and a diversity of alteration minerals indicative of acidic conditions. Based on these terrestrial observations, the presence of opal-CT and/or microcrystalline quartz could be more diagnostic of a hot spring origin rather than a fumarolic origin, and accessory mineralogy could provide information on formation pH. On Mars, we observe that most orbital opal detections in outcrop are opal-A, sometimes accompanied by Fe/Mg clays, suggestive of neutral/alkaline conditions. However, these observations do not uniquely distinguish between hot springs and fumarolic environments, as opal-A can occur in both environments. Many martian silica detections occur in regionally extensive units, and sometimes in association with fluvial landforms suggesting a detrital or lower temperature authigenic origin. Thus, only a few martian opal detections may be mineralogically, spatially, and morphologically consistent with a hot spring origin. However, although it is difficult to unambiguously identify martian hot spring environments from orbital data sets, the orbital data are still valuable for identifying siliceous sites that are consistent with higher biosignature preservation potential, that is, sites with opal-A (not opal-CT), for future in situ investigations.
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Affiliation(s)
- Vivian Z Sun
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Ralph E Milliken
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island
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56
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Tan J, Sephton MA. Organic Records of Early Life on Mars: The Role of Iron, Burial, and Kinetics on Preservation. ASTROBIOLOGY 2020; 20:53-72. [PMID: 31755737 PMCID: PMC6987739 DOI: 10.1089/ast.2019.2046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 09/11/2019] [Indexed: 05/19/2023]
Abstract
Samples that are likely to contain evidence of past life on Mars must have been deposited when and where environments exhibited habitable conditions. Mars analog sites provide the opportunity to study how life could have exploited such habitable conditions. Acidic iron- and sulfur-rich streams are good geochemical analogues for the late Noachian and early Hesperian, periods of martian history where habitable conditions were widespread. Past life on Mars would have left behind fossilized microbial organic remains. These are often-sought diagnostic evidence, but they must be shielded from the harsh radiation flux at the martian surface and its deleterious effect on organic matter. One mechanism that promotes such preservation is burial, which raises questions about how organic biomarkers are influenced by the postburial effects of diagenesis. We investigated the kinetics of organic degradation in the subsurface of Mars. Natural mixtures of acidic iron- and sulfur-rich stream sediments and their associated microbial populations and remains were subjected to hydrous pyrolysis, which simulated the increased temperatures and pressures of burial alongside any promoted organic/mineral interactions. Calculations were made to extrapolate the observed changes over martian history. Our experiments indicate that low carbon contents, high water-to-rock ratios, and the presence of iron-rich minerals combine to provide unfavorable conditions for the preservation of soluble organic matter over the billions of years necessary to produce present-day organic records of late Noachian and early Hesperian life on Mars. Successful sample selection strategies must therefore consider the pre-, syn-, and postburial histories of sedimentary records on Mars and the balance between the production of biomass and the long-term preservation of organic biomarkers over geological time.
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Affiliation(s)
- Jonathan Tan
- Department of Earth Science and Engineering, Impacts and Astromaterials Research Centre, Imperial College London, London, United Kingdom
- Address correspondence to: Jonathan Tan, Department of Earth Science and Engineering, Impacts and Astromaterials Research Centre, Imperial College London, London SW7 2AZ, United Kingdom
| | - Mark A. Sephton
- Department of Earth Science and Engineering, Impacts and Astromaterials Research Centre, Imperial College London, London, United Kingdom
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57
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Preston LJ, Barcenilla R, Dartnell LR, Kucukkilic-Stephens E, Olsson-Francis K. Infrared Spectroscopic Detection of Biosignatures at Lake Tírez, Spain: Implications for Mars. ASTROBIOLOGY 2020; 20:15-25. [PMID: 31592682 PMCID: PMC6987737 DOI: 10.1089/ast.2019.2106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/13/2019] [Indexed: 06/10/2023]
Abstract
The detection of potential biosignatures with mineral matrices is part of a multifaceted approach in the search for life on other planetary bodies. The 2020 ExoMars Rosalind Franklin rover includes within its payload three IR spectrometers in the form of ISEM (Infrared Spectrometer for ExoMars), MicrOmega, and Ma-MISS (Mars Multispectral Imager for Subsurface Studies). The use of this technique in the detection and characterization of biosignatures is of great value. Organic materials are often co-deposited in terrestrial evaporites and as such have been proposed as relevant analogs in the search for life on Mars. This study focuses on Ca-sulfates collected from the hypersaline Tírez Lake in Spain. Mid infrared and visible near infrared analysis of soils, salt crusts, and crystals with green and red layering indicative of microbial colonization of the samples was acquired from across the lake and identified the main mineral to be gypsum with inputs of carbonate and silica. Organic functional groups that could be attributed to amides and carboxylic acids were identified as well as chlorophyll; however, due to the strong mineralogical absorptions observed, these were hard to unambiguously discern. Taxonomical assignment demonstrated that the archaeal community within the samples was dominated by the halophilic extremophile Halobacteriaceae while the bacterial community was dominated by the class Nocardiaceae. The results of this research highlight that sulfates on Mars are a mixed blessing, acting as an effective host for organic matter preservation but also a material that masks the presence of organic functional groups when analyzed with spectroscopic tools similar to those due to fly on the 2020 ExoMars rover. A suite of complementary analytical techniques therefore should be used to support the spectral identification of any candidate extraterrestrial biosignatures.
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Affiliation(s)
- Louisa J. Preston
- Department of Earth and Planetary Sciences, Birkbeck College, University of London, London, UK
| | - Rebeca Barcenilla
- Department of Earth and Planetary Sciences, Birkbeck College, University of London, London, UK
- Department of Life Sciences, University of Westminster, London, UK
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58
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Cohen BA, Malespin CA, Farley KA, Martin PE, Cho Y, Mahaffy PR. In Situ Geochronology on Mars and the Development of Future Instrumentation. ASTROBIOLOGY 2019; 19:1303-1314. [PMID: 31361510 PMCID: PMC6818483 DOI: 10.1089/ast.2018.1871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/15/2019] [Indexed: 05/25/2023]
Abstract
We review the in situ geochronology experiments conducted by the Mars Science Laboratory mission's Curiosity rover to understand when the Gale Crater rocks formed, underwent alteration, and became exposed to cosmogenic radiation. These experiments determined that the detrital minerals in the sedimentary rocks of Gale are ∼4 Ga, consistent with their origin in the basalts surrounding the crater. The sedimentary rocks underwent fluid-moderated alteration 2 Gyr later, which may mark the closure of aqueous activity at Gale Crater. Over the past several million years, wind-driven processes have dominated, denuding the surfaces by scarp retreat. The Curiosity measurements validate radiometric dating techniques on Mars and guide the way for future instrumentation to make more precise measurements that will further our understanding of the geological and astrobiological history of the planet.
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Affiliation(s)
- Barbara A. Cohen
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Charles A. Malespin
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Kenneth A. Farley
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
| | - Peter E. Martin
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
| | - Yuichiro Cho
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Paul R. Mahaffy
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
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Fukushi K, Sekine Y, Sakuma H, Morida K, Wordsworth R. Semiarid climate and hyposaline lake on early Mars inferred from reconstructed water chemistry at Gale. Nat Commun 2019; 10:4896. [PMID: 31653859 PMCID: PMC6814795 DOI: 10.1038/s41467-019-12871-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/01/2019] [Indexed: 12/02/2022] Open
Abstract
Salinity, pH, and redox states are fundamental properties that characterize natural waters. These properties of surface waters on early Mars reflect palaeoenvironments, and thus provide clues on the palaeoclimate and habitability. Here we constrain these properties of pore water within lacustrine sediments of Gale Crater, Mars, using smectite interlayer compositions. Regardless of formation conditions of smectite, the pore water that last interacted with the sediments was of Na-Cl type with mild salinity (~0.1-0.5 mol/kg) and circumneutral pH. To interpret this, multiple scenarios for post-depositional alterations are considered. The estimated Na-Cl concentrations would reflect hyposaline, early lakes developed in 104-106-year-long semiarid climates. Assuming that post-depositional sulfate-rich fluids interacted with the sediments, the redox disequilibria in secondary minerals suggest infiltration of oxidizing fluids into reducing sediments. Assuming no interactions, the redox disequilibria could have been generated by interactions of upwelling groundwater with oxidized sediments in early post-depositional stages.
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Affiliation(s)
- Keisuke Fukushi
- Institute of Nature and Environmental Technology, Kanazawa University, Kanazawa, Ishikawa, Japan.
| | - Yasuhito Sekine
- Institute of Nature and Environmental Technology, Kanazawa University, Kanazawa, Ishikawa, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Hiroshi Sakuma
- National Institute for Materials Science, Tsukuba, Ibaraki, Japan
| | - Koki Morida
- Division of Natural System, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Robin Wordsworth
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
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Microbial Markers Profile in Anaerobic Mars Analogue Environments Using the LDChip (Life Detector Chip) Antibody Microarray Core of the SOLID (Signs of Life Detector) Platform. Microorganisms 2019; 7:microorganisms7090365. [PMID: 31540500 PMCID: PMC6780502 DOI: 10.3390/microorganisms7090365] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/30/2019] [Accepted: 09/16/2019] [Indexed: 11/30/2022] Open
Abstract
One of the main objectives for astrobiology is to unravel and explore the habitability of environments beyond Earth, paying special attention to Mars. If the combined environmental stress factors on Mars are compatible with life or if they were less harsh in the past, to investigate the traces of past or present life is critical to understand its potential habitability. Essential for this research is the characterization of Mars analogue environments on Earth through the development of techniques for biomarker detection in them. Biosensing techniques based on fluorescence sandwich microarray immunoassays (FSMI) have shown to be a powerful tool to detect biosignatures and depict the microbial profiles of different environments. In this study, we described the microbial biomarker profile of five anoxic Mars analogues sites using the Life Detector Chip (LDChip), an antibody microarray for multiple microbial marker detection. Furthermore, we contributed to new targets by developing a new 26-polyclonal antibodies microarray using crude extracts from anaerobic sampling sites, halophilic microorganisms, and anaerobic isolates obtained in the framework of the European Mars Analogues for Space Exploration (MASE) project. The new subset of antibodies was characterized and implemented into a microarray platform (MASE-Chip) for microbial marker searching in salty and anaerobic environments.
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Performance of the SAM gas chromatographic columns under simulated flight operating conditions for the analysis of chlorohydrocarbons on Mars. J Chromatogr A 2019; 1598:183-195. [DOI: 10.1016/j.chroma.2019.03.064] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/27/2019] [Accepted: 03/28/2019] [Indexed: 11/21/2022]
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Baú JPT, Valezi DF, Villafañe-Barajas SA, Colín-García M, Negrón-Mendoza A, Di Mauro E, Zaia DA. Solid adenine and seawater salts exposed to gamma radiation: An FT-IR and EPR spectroscopy analysis for prebiotic chemistry. Heliyon 2019; 5:e01584. [PMID: 31193064 PMCID: PMC6514728 DOI: 10.1016/j.heliyon.2019.e01584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 04/24/2019] [Accepted: 04/25/2019] [Indexed: 11/30/2022] Open
Abstract
Solids of adenine obtained from distilled water and seawater lyophilized solutions were γ irradiated at a 94.52 kGy dose. Results indicate that pure solid adenine had a low degradation rate, likewise the solid containing seawater salts. However, EPR spectroscopy analysis suggests a high interaction of the radiation with seawater salts, by radical formation in sulfate ions. These outcomes are of interest for prebiotic chemistry, since ions could have played important roles in chemical evolution. In addition, Martian soil is rich in sulphate salts, thus these salts could protected organic molecules being degraded by γ-radiation.
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Affiliation(s)
- João Paulo T. Baú
- Laboratório de Química Prebiótica, Departamento de Química-CCE, Universidade Estadual de Londrina, 86051-990, Londrina, PR, Brazil
| | - Daniel F. Valezi
- Laboratório de Ressonância Paramagnética Eletrônica (LARPE), Departamento de Física-CCE, Universidade Estadual de Londrina, 86051-990, Londrina, PR, Brazil
| | - Sául A. Villafañe-Barajas
- Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Cd. Mx., Mexico
| | - María Colín-García
- Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Cd. Mx., Mexico
- Corresponding author.
| | - Alicia Negrón-Mendoza
- Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Cd. Mx, Mexico
| | - Eduardo Di Mauro
- Laboratório de Ressonância Paramagnética Eletrônica (LARPE), Departamento de Física-CCE, Universidade Estadual de Londrina, 86051-990, Londrina, PR, Brazil
| | - Dimas A.M. Zaia
- Laboratório de Química Prebiótica, Departamento de Química-CCE, Universidade Estadual de Londrina, 86051-990, Londrina, PR, Brazil
- Corresponding author.
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Record of low-temperature aqueous alteration of Martian zircon during the late Amazonian. Nat Commun 2019; 10:2457. [PMID: 31186423 PMCID: PMC6559952 DOI: 10.1038/s41467-019-10382-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 04/30/2019] [Indexed: 12/03/2022] Open
Abstract
Several lines of evidence support the presence of liquid water on Mars at different times. Among those, hydrated minerals testify to past aqueous weathering processes that can be precisely studied in Martian meteorites such as NWA 7533/7034. Bringing constraints on the timing of weathering of the Martian crust would help understand its evolution, the availability of liquid water, and the habitability of Mars. Here we present a new method based on U–Th–Pb isotope systems to assess if zircon crystals underwent low-temperature aqueous alteration, such as exemplified by Hadean-aged detrital crystals from Western Australia. Data for NWA 7533 zircons show evidence for aqueous alteration and modeling of U–Th–Pb isotope system evolution indicates that the latest alteration event occurred during the late Amazonian (227–56 Ma). This finding largely expands the time duration over which liquid water was available near the Martian surface, thereby suggesting that Mars might still be habitable. When liquid water was present on Mars is still debated. The authors here date the age of aqueous alteration experienced by zircons from a Martian meteorite and show that liquid water was present on Mars during the Late Amazonian, thus, in a recent past.
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Ward LM, Stamenković V, Hand K, Fischer WW. Follow the Oxygen: Comparative Histories of Planetary Oxygenation and Opportunities for Aerobic Life. ASTROBIOLOGY 2019; 19:811-824. [PMID: 31188035 DOI: 10.1089/ast.2017.1779] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Aerobic respiration-the reduction of molecular oxygen (O2) coupled to the oxidation of reduced compounds such as organic carbon, ferrous iron, reduced sulfur compounds, or molecular hydrogen while conserving energy to drive cellular processes-is the most widespread and bioenergetically favorable metabolism on Earth today. Aerobic respiration is essential for the development of complex multicellular life; thus the presence of abundant O2 is an important metric for planetary habitability. O2 on Earth is supplied by oxygenic photosynthesis, but it is becoming more widely understood that abiotic processes may supply meaningful amounts of O2 on other worlds. The modern atmosphere and rock record of Mars suggest a history of relatively high O2 as a result of photochemical processes, potentially overlapping with the range of O2 concentrations used by biology. Europa may have accumulated high O2 concentrations in its subsurface ocean due to the radiolysis of water ice at its surface. Recent modeling efforts suggest that coexisting water and O2 may be common on exoplanets, with confirmation from measurements of exoplanet atmospheres potentially coming soon. In all these cases, O2 accumulates through abiotic processes-independent of water-oxidizing photosynthesis. We hypothesize that abiogenic O2 may enhance the habitability of some planetary environments, allowing highly energetic aerobic respiration and potentially even the development of complex multicellular life which depends on it, without the need to first evolve oxygenic photosynthesis. This hypothesis is testable with further exploration and life-detection efforts on O2-rich worlds such as Mars and Europa, and comparison to O2-poor worlds such as Enceladus. This hypothesis further suggests a new dimension to planetary habitability: "Follow the Oxygen," in which environments with opportunities for energy-rich metabolisms such as aerobic respiration are preferentially targeted for investigation and life detection.
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Affiliation(s)
- Lewis M Ward
- 1 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
| | - Vlada Stamenković
- 2 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Kevin Hand
- 2 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Woodward W Fischer
- 1 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
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Aerts JW, van Spanning RJM, Flahaut J, Molenaar D, Bland PA, Genge MJ, Ehrenfreund P, Martins Z. Microbial Communities in Sediments From Four Mildly Acidic Ephemeral Salt Lakes in the Yilgarn Craton (Australia) - Terrestrial Analogs to Ancient Mars. Front Microbiol 2019; 10:779. [PMID: 31133990 PMCID: PMC6512757 DOI: 10.3389/fmicb.2019.00779] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 03/27/2019] [Indexed: 11/24/2022] Open
Abstract
The Yilgarn Craton in Australia has a large number of naturally occurring shallow ephemeral lakes underlain by a dendritic system of paleodrainage channels. Processes like evaporation, flooding, erosion, as well as inflow of saline, often acidic and ion-rich groundwater contribute to the (dynamic) nature of the lakes and the composition of the sediments. The region has previously been described as an analog environment for early Mars due to its geological and geophysical similarities. Here, we investigated sediment samples of four lake environments aimed at getting a fundamental understanding of the native microbial communities and the mineralogical and (bio)chemical composition of the sediments they are associated with. The dominant mineral phases in the sediments were quartz, feldspars and amphiboles, while halite and gypsum were the only evaporites detected. Element analysis revealed a rich and complex image, in which silicon, iron, and aluminum were the dominant ions, but relative high concentrations of trace elements such as strontium, chromium, zirconium, and barium were also found. The concentrations of organic carbon, nitrogen, and phosphorus were generally low. 16S amplicon sequencing on the Illumina platform showed the presence of diverse microbial communities in all four lake environments. We found that most of the communities were dominated by extremely halophilic Archaea of the Halobacteriaceae family. The dynamic nature of these lakes appears to influence the biological, biochemical, and geological components of the ecosystem to a large effect. Inter- and intra-lake variations in the distributions of microbial communities were significant, and could only to a minor degree be explained by underlying environmental conditions. The communities are likely significantly influenced by small scale local effects caused by variations in geological settings and dynamic interactions caused by aeolian transport and flooding and evaporation events.
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Affiliation(s)
- Joost W Aerts
- Department of Molecular Cell Biology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Rob J M van Spanning
- Department of Molecular Cell Biology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Jessica Flahaut
- Centre de Recherches Pétrographiques et Géochimiques, Centre National de la Recherche Scientifique/Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Douwe Molenaar
- Department of Molecular Cell Biology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Phil A Bland
- Department of Applied Geology, Curtin University, Perth, WA, Australia
| | - Matt J Genge
- Department of Earth Science and Engineering, Faculty of Engineering, Imperial College London, London, United Kingdom
| | - Pascale Ehrenfreund
- Leiden Observatory, Leiden University, Leiden, Netherlands.,Space Policy Institute, Elliott School of International Affairs, George Washington University, Washington, DC, United States
| | - Zita Martins
- Centro de Química-Física Molecular-Institute of Nanoscience and Nanotechnology (CQFM-IN), Institute for Bioengineering and Biosciences (iBB), Departamento de Engenharia Química, Instituto Superior Técnico (IST), Universidade de Lisboa, Lisbon, Portugal
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66
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Lowe DR, Bishop JL, Loizeau D, Wray JJ, Beyer RA. Deposition of >3.7 Ga clay-rich strata of the Mawrth Vallis Group, Mars, in lacustrine, alluvial, and aeolian environments. GEOLOGICAL SOCIETY OF AMERICA BULLETIN 2019; 132:17-30. [PMID: 33958812 PMCID: PMC8098079 DOI: 10.1130/b35185.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The presence of abundant phyllosilicate minerals in Noachian (>3.7 Ga) rocks on Mars has been taken as evidence that liquid water was stable at or near the surface early in martian history. This study investigates some of these clay-rich strata exposed in crater rim and inverted terrain settings in the Mawrth Vallis region of Mars. In Muara crater the 200-m-thick, clay-rich Mawrth Vallis Group (MVG) is subdivided into five informal units numbered 1 (base) to 5 (top). Unit 1 consists of interbedded sedimentary and volcanic or volcaniclastic units showing weak Fe/Mg-smectite alteration deposited in a range of subaerial depositional settings. Above a major unconformity eroded on Unit 1, the dark-toned sediments of Unit 2 and lower Unit 3 are inferred to represent mainly wind-blown sand. These are widely interlayered with and draped by thin layers of light-toned sediment representing fine suspended-load aeolian silt and clay. These sediments show extensive Fe/Mg-smectite alteration, probably reflecting subaerial weathering. Upper Unit 3 and units 4 and 5 are composed of well-layered, fine-grained sediment dominated by Al-phyllosilicates, kaolinite, and hydrated silica. Deposition occurred in a large lake or arm of a martian sea. In the inverted terrain 100 km to the NE, Unit 4 shows very young slope failures suggesting that the clay-rich sediments today retain a significant component of water ice. The MVG provides evidence for the presence of large, persistent standing bodies of water on early Mars as well as a complex association of flanking shoreline, alluvial, and aeolian systems. Some of the clays, especially the Fe/Mg smectites in upper units 1 and 2 appear to have formed through subaerial weathering whereas the aluminosilicates, kaolinite, and hydrated silica of units 3, 4, and 5 formed mainly through alteration of fine sediment in subaqueous environments.
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Affiliation(s)
- Donald R. Lowe
- Department of Geological Sciences, Stanford University, Stanford, California 94305-2115, USA
| | - Janice L. Bishop
- SETI & NASA-Ames Research Center, Mountain View, California, USA
| | - Damien Loizeau
- Université Claude Bernard Lyon 1, Ens de Lyon, CNRS, UMR 5276 LGL-TPE, F-69622, Villeurbanne, France
- Institut d’Astrophysique Spatiale, Université Paris Sud, F-91405 Orsay, France
| | - James J. Wray
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332-0340, USA
| | - Ross A. Beyer
- SETI & NASA-Ames Research Center, Mountain View, California, USA
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Kulichenko M, Fedik N, Bozhenko KV, Boldyrev AI. Hydrated Sulfate Clusters SO42–(H2O)n (n = 1–40): Charge Distribution Through Solvation Shells and Stabilization. J Phys Chem B 2019; 123:4065-4069. [DOI: 10.1021/acs.jpcb.9b01744] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maksim Kulichenko
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah 84322-0300, United States
| | - Nikita Fedik
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah 84322-0300, United States
| | - Konstantin V. Bozhenko
- Department of Physical and Colloid Chemistry, Peoples’ Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya St, Moscow 117198, Russian Federation
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russian Federation
| | - Alexander I. Boldyrev
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah 84322-0300, United States
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Chan MA, Bowen BB, Corsetti FA, Farrand WH, Law ES, Newsom HE, Perl SM, Spear JR, Thompson DR. Exploring, Mapping, and Data Management Integration of Habitable Environments in Astrobiology. Front Microbiol 2019; 10:147. [PMID: 30891006 PMCID: PMC6412026 DOI: 10.3389/fmicb.2019.00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 01/21/2019] [Indexed: 11/17/2022] Open
Abstract
New approaches to blending geoscience, planetary science, microbiology-geobiology/ecology, geoinformatics and cyberinfrastructure technology disciplines in a holistic effort can be transformative to astrobiology explorations. Over the last two decades, overwhelming orbital evidence has confirmed the abundance of authigenic (in situ, formed in place) minerals on Mars. On Earth, environments where authigenic minerals form provide a substrate for the preservation of microbial life. Similarly, extraterrestrial life is likely to be preserved where crustal minerals can record and preserve the biochemical mechanisms (i.e., biosignatures). The search for astrobiological evidence on Mars has focused on identifying past or present habitable environments - places that could support some semblance of life. Thus, authigenic minerals represent a promising habitable environment where extraterrestrial life could be recorded and potentially preserved over geologic time scales. Astrobiology research necessarily takes place over vastly different scales; from molecules to viruses and microbes to those of satellites and solar system exploration, but the differing scales of analyses are rarely connected quantitatively. The mismatch between the scales of these observations- from the macro- satellite mineralogical observations to the micro- microbial observations- limits the applicability of our astrobiological understanding as we search for records of life beyond Earth. Each-scale observation requires knowledge of the geologic context and the environmental parameters important for assessing habitability. Exploration efforts to search for extraterrestrial life should attempt to quantify both the geospatial context and the temporal/spatial relationships between microbial abundance and diversity within authigenic minerals at multiple scales, while assimilating resolutions from satellite observations to field measurements to microscopic analyses. Statistical measures, computer vision, and the geospatial synergy of Geographic Information Systems (GIS), can allow analyses of objective data-driven methods to locate, map, and predict where the "sweet spots" of habitable environments occur at multiple scales. This approach of science information architecture or an "Astrobiology Information System" can provide the necessary maps to guide researchers to discoveries via testing, visualizing, documenting, and collaborating on significant data relationships that will advance explorations for evidence of life in our solar system and beyond.
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Affiliation(s)
- Marjorie A. Chan
- Department of Geology and Geophysics, The University of Utah, Salt Lake City, UT, United States
| | - Brenda B. Bowen
- Department of Geology and Geophysics, The University of Utah, Salt Lake City, UT, United States
| | - Frank A. Corsetti
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | | | - Emily S. Law
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Horton E. Newsom
- Department Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM, United States
| | - Scott M. Perl
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - John R. Spear
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, United States
| | - David R. Thompson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
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Cockell CS, Harrison JP, Stevens AH, Payler SJ, Hughes SS, Kobs Nawotniak SE, Brady AL, Elphic R, Haberle CW, Sehlke A, Beaton KH, Abercromby AF, Schwendner P, Wadsworth J, Landenmark H, Cane R, Dickinson AW, Nicholson N, Perera L, Lim DS. A Low-Diversity Microbiota Inhabits Extreme Terrestrial Basaltic Terrains and Their Fumaroles: Implications for the Exploration of Mars. ASTROBIOLOGY 2019; 19:284-299. [PMID: 30840501 PMCID: PMC6442273 DOI: 10.1089/ast.2018.1870] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A major objective in the exploration of Mars is to test the hypothesis that the planet hosted life. Even in the absence of life, the mapping of habitable and uninhabitable environments is an essential task in developing a complete understanding of the geological and aqueous history of Mars and, as a consequence, understanding what factors caused Earth to take a different trajectory of biological potential. We carried out the aseptic collection of samples and comparison of the bacterial and archaeal communities associated with basaltic fumaroles and rocks of varying weathering states in Hawai'i to test four hypotheses concerning the diversity of life in these environments. Using high-throughput sequencing, we found that all these materials are inhabited by a low-diversity biota. Multivariate analyses of bacterial community data showed a clear separation between sites that have active fumaroles and other sites that comprised relict fumaroles, unaltered, and syn-emplacement basalts. Contrary to our hypothesis that high water flow environments, such as fumaroles with active mineral leaching, would be sites of high biological diversity, alpha diversity was lower in active fumaroles compared to relict or nonfumarolic sites, potentially due to high-temperature constraints on microbial diversity in fumarolic sites. A comparison of these data with communities inhabiting unaltered and weathered basaltic rocks in Idaho suggests that bacterial taxon composition of basaltic materials varies between sites, although the archaeal communities were similar in Hawai'i and Idaho. The taxa present in both sites suggest that most of them obtain organic carbon compounds from the atmosphere and from phototrophs and that some of them, including archaeal taxa, cycle fixed nitrogen. The low diversity shows that, on Earth, extreme basaltic terrains are environments on the edge of sustaining life with implications for the biological potential of similar environments on Mars and their exploration by robots and humans.
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Affiliation(s)
- Charles S. Cockell
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
- Address correspondence to: Charles S. Cockell, School of Physics and Astronomy, University of Edinburgh, King's Buildings, Edinburgh EH9 3JZ, UK
| | - Jesse P. Harrison
- Aquatic Biogeochemistry Research Unit, Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland
| | - Adam H. Stevens
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Samuel J. Payler
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Scott S. Hughes
- Department of Geosciences, Idaho State University, Pocatello, Idaho, USA
| | | | - Allyson L. Brady
- School of Geography and Earth Sciences, McMaster University, Hamilton, Canada
| | - R.C. Elphic
- NASA Ames Research Center, Mountain View, California, USA
| | | | | | | | - Andrew F.J. Abercromby
- Biomedical Research & Environmental Sciences Division (SK), NASA Johnson Space Center, Houston, Texas, USA
| | - Petra Schwendner
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Jennifer Wadsworth
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Hanna Landenmark
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Rosie Cane
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Andrew W. Dickinson
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Natasha Nicholson
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Liam Perera
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Darlene S.S. Lim
- NASA Ames Research Center, Mountain View, California, USA
- Bay Area Environmental Research Institute (BAERI), Moffett Field, California, USA
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70
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Sehlke A, Mirmalek Z, Burtt D, Haberle CW, Santiago-Materese D, Kobs Nawotniak SE, Hughes SS, Garry WB, Bramall N, Brown AJ, Heldmann JL, Lim DS. Requirements for Portable Instrument Suites during Human Scientific Exploration of Mars. ASTROBIOLOGY 2019; 19:401-425. [PMID: 30840506 PMCID: PMC6442242 DOI: 10.1089/ast.2018.1841] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 10/28/2018] [Indexed: 05/31/2023]
Abstract
Human explorers on the surface of Mars will have access to a far wider array of scientific tools than previous crewed planetary exploration missions, but not every tool will be compatible with the restrictions of this exploration. Spectrometers on flyby, orbital, and landed missions are currently used to determine the composition and mineralogy of geological materials of various types and sizes, from small fragments to celestial bodies in the solar system. Handheld spectrometers that are capable of in situ analyses are already used for geological exploration on Earth; however, their usefulness for human exploration missions and how data from multiple handheld instruments could be combined to enhance scientific return must be further evaluated. As part of the Biologic Analog Science Associated with Lava Terrains (BASALT) research project, we incorporated two handheld instruments, a visible-near infrared spectrometer and an X-Ray Fluorescence spectrometer, into simulated Mars exploration missions conducted on basaltic terrains in Idaho and Hawai'i. To understand the data quality provided by these handheld spectrometers, we evaluated their performance under varying conditions of measurement time, distance, angle, atmosphere, and sample matrix, and we compared data quality between handheld instruments and laboratory techniques. Here, we summarize these findings, provide guidelines and requirements on how to effectively incorporate these instruments into human exploration missions to Mars, and posit that future iterations of these instruments will be beneficial for enhancing science returned from human exploration missions.
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Affiliation(s)
| | - Zara Mirmalek
- Kennedy School of Government, Harvard University, Cambridge, Massachusetts
- BAER Institute, Moffett Field, California
| | - David Burtt
- Department of Geosciences, Stony Brook University, Stony Brook, New York
| | | | | | | | - Scott S. Hughes
- Deparment of Geosciences, Idaho State University, Pocatello, Idaho
| | | | - Nathan Bramall
- Leiden Measurement Technology LLC, Sunnyvale, California
| | | | | | - Darlene S.S. Lim
- NASA Ames Research Center, Moffett Field, California
- BAER Institute, Moffett Field, California
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71
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Salese F, Pondrelli M, Neeseman A, Schmidt G, Ori GG. Geological Evidence of Planet-Wide Groundwater System on Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2019; 124:374-395. [PMID: 31007995 PMCID: PMC6472477 DOI: 10.1029/2018je005802] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 01/12/2019] [Accepted: 01/15/2019] [Indexed: 05/20/2023]
Abstract
The scale of groundwater upwelling on Mars, as well as its relation to sedimentary systems, remains an ongoing debate. Several deep craters (basins) in the northern equatorial regions show compelling signs that large amounts of water once existed on Mars at a planet-wide scale. The presence of water-formed features, including fluvial Gilbert and sapping deltas fed by sapping valleys, constitute strong evidence of groundwater upwelling resulting in long term standing bodies of water inside the basins. Terrestrial field evidence shows that sapping valleys can occur in basalt bedrock and not only in unconsolidated sediments. A hypothesis that considers the elevation differences between the observed morphologies and the assumed basal groundwater level is presented and described as the "dike-confined water" model, already present on Earth and introduced for the first time in the Martian geological literature. Only the deepest basins considered in this study, those with bases deeper than -4000 m in elevation below the Mars datum, intercepted the water-saturated zone and exhibit evidence of groundwater fluctuations. The discovery of these groundwater discharge sites on a planet-wide scale strongly suggests a link between the putative Martian ocean and various configurations of sedimentary deposits that were formed as a result of groundwater fluctuations during the Hesperian period. This newly recognized evidence of water-formed features significantly increases the chance that biosignatures could be buried in the sediment. These deep basins (groundwater-fed lakes) will be of interest to future exploration missions as they might provide evidence of geological conditions suitable for life.
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Affiliation(s)
- Francesco Salese
- Faculty of GeosciencesUtrecht UniversityUtrechtThe Netherlands
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
| | - Monica Pondrelli
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
| | - Alicia Neeseman
- Institute of Geological Sciences, Planetary Sciences and Remote Sensing GroupFreie Universität BerlinBerlinGermany
| | - Gene Schmidt
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
| | - Gian Gabriele Ori
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
- Ibn Battuta CentreUniversité Cadi AyyadMarrakeshMorocco
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Experimental studies addressing the longevity of Bacillus subtilis spores - The first data from a 500-year experiment. PLoS One 2018; 13:e0208425. [PMID: 30513104 PMCID: PMC6279046 DOI: 10.1371/journal.pone.0208425] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 11/17/2018] [Indexed: 11/23/2022] Open
Abstract
The ability to form endospores allows certain Gram-positive bacteria (e.g. Bacillus subtilis) to challenge the limits of microbial resistance and survival. Thus, B. subtilis is able to tolerate many environmental extremes by transitioning into a dormant state as spores, allowing survival under otherwise unfavorable conditions. Despite thorough study of spore resistance to external stresses, precisely how long B. subtilis spores can lie dormant while remaining viable, a period that potentially far exceeds the human lifespan; is not known although convincing examples of long term spore survival have been recorded. In this study, we report the first data from a 500-year microbial experiment, which started in 2014 and will finish in 2514. A set of vials containing a defined concentration of desiccated B. subtilis spores is opened and tested for viability every two years for the first 24 years and then every 25 years until experiment completion. Desiccated baseline spore samples were also exposed to environmental stresses, including X-rays, 254 nm UV-C, 10% H2O2, dry heat (120°C) and wet heat (100°C) to investigate how desiccated spores respond to harsh environmental conditions after long periods of storage. Data from the first 2 years of storage show no significant decrease in spore viability. Additionally, spores of B. subtilis were subjected to various short-term storage experiments, revealing that space-like vacuum and high NaCl concentration negatively affected spore viability.
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73
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Yoshida H, Hasegawa H, Katsuta N, Maruyama I, Sirono S, Minami M, Asahara Y, Nishimoto S, Yamaguchi Y, Ichinnorov N, Metcalfe R. Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars. SCIENCE ADVANCES 2018; 4:eaau0872. [PMID: 30525103 PMCID: PMC6281427 DOI: 10.1126/sciadv.aau0872] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
Spherical Fe-oxide concretions on Earth, especially in Utah, USA, have been investigated as an analog of hematite spherules found in Meridiani Planum on Mars to support interpretations of water-rock interactions in early Mars. Although several formation mechanisms have been proposed for the Fe-oxide concretions on Earth, it is still unclear whether these mechanisms are viable because a precise formation process and precursor of the concretions are missing. This paper presents evidence that Fe-oxide concretions in Utah and newly found Fe-oxide concretions in Mongolia had spherical calcite concretions as precursors. Different formation stages of calcite and Fe-oxide concretions observed, both in Utah and Mongolia, indicate that calcite concretions initially formed within eolian sandstone strata and were dissolved by infiltrating Fe-rich acidic waters to form spherical FeO(OH) crusts due to pH buffering. The similarity between these Fe-oxide concretions on Earth and the hematite spherule occurrences in Meridiani Planum, combined with evidence of acid sulfate water influences on Mars, suggest that the hematite spherules also formed from dissolution of preexisting carbonate spherules possibly formed under a dense carbon dioxide early martian atmosphere.
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Affiliation(s)
- H. Yoshida
- Material Research Section, Nagoya University, University Museum, Nagoya, Japan
| | - H. Hasegawa
- Material Research Section, Nagoya University, University Museum, Nagoya, Japan
- Faculty of Science and Technology, Kochi University, Kochi, Japan
| | - N. Katsuta
- Faculty of Education, Gifu University, Gifu, Japan
| | - I. Maruyama
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
| | - S. Sirono
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
| | - M. Minami
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - Y. Asahara
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
| | | | - Y. Yamaguchi
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
| | - N. Ichinnorov
- Institute of Paleontology and Geology, Mongolian Academy of Science, Mongolia
| | - R. Metcalfe
- Quintessa Limited, The Hub, Henley-on-Thames, Oxfordshire, UK
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74
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Pulschen AA, de Araujo GG, de Carvalho ACSR, Cerini MF, Fonseca LDM, Galante D, Rodrigues F. Survival of Extremophilic Yeasts in the Stratospheric Environment during Balloon Flights and in Laboratory Simulations. Appl Environ Microbiol 2018; 84:e01942-18. [PMID: 30266724 PMCID: PMC6238051 DOI: 10.1128/aem.01942-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 09/12/2018] [Indexed: 12/13/2022] Open
Abstract
The high-altitude atmosphere is a harsh environment with extremely low temperatures, low pressure, and high UV irradiation. For this reason, it has been proposed as an analogue for Mars, presenting deleterious factors similar to those on the surface of that planet. We evaluated the survival of extremophilic UV-resistant yeasts isolated from a high-elevation area in the Atacama Desert under stratospheric conditions. As biological controls, intrinsically resistant Bacillus subtilis spores were used. Experiments were performed in two independent stratospheric balloon flights and with an environmental simulation chamber. The three following different conditions were evaluated: (i) desiccation, (ii) desiccation plus exposure to stratospheric low pressure and temperature, and (3) desiccation plus exposure to the full stratospheric environment (UV, low pressure, and temperature). Two strains, Naganishia (Cryptococcus) friedmannii 16LV2 and Exophiala sp. strain 15LV1, survived full exposures to the stratosphere in larger numbers than did B. subtilis spores. Holtermanniella watticus (also known as Holtermanniella wattica) 16LV1, however, suffered a substantial loss in viability upon desiccation and did not survive the stratospheric UV exposure. The remarkable resilience of N. friedmannii and Exophiala sp. 15LV1 under the extreme Mars-like conditions of the stratosphere confirms its potential as a eukaryotic model for astrobiology. Additionally, our results with N. friedmannii strengthen the recent hypothesis that yeasts belonging to the Naganishia genus are fit for aerial dispersion, which might account for the observed abundance of this species in high-elevation soils.IMPORTANCE Studies of eukaryotic microorganisms under conditions of astrobiological relevance, as well as the aerial dispersion potential of extremophilic yeasts, are still lacking in the literature compared to works with bacteria. Using stratospheric balloon flights and a simulation chamber, we demonstrate that yeasts isolated from an extreme environment are capable of surviving all stressors found in the stratosphere, including intense UV irradiation, scoring an even higher survival than B. subtilis spores. Notably, the yeast N. friedmannii, which displayed one of the highest tolerances to the stratospheric environment in the experiments, was recently proposed to be adapted to airborne transportation, although such a hypothesis had not yet been tested. Our results strengthen such an assumption and can help explain the observed distribution and ecology of this particular yeast species.
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Affiliation(s)
| | | | | | - Maria Fernanda Cerini
- Graduate Program in Biomolecular Physics, São Carlos Institute of Physics, University of São Paulo, São Paulo, Brazil
- Brazilian Synchrotron Light Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo, Brazil
| | | | - Douglas Galante
- Graduate Program in Biomolecular Physics, São Carlos Institute of Physics, University of São Paulo, São Paulo, Brazil
- Brazilian Synchrotron Light Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo, Brazil
| | - Fabio Rodrigues
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
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75
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Fornaro T, Steele A, Brucato JR. Catalytic/Protective Properties of Martian Minerals and Implications for Possible Origin of Life on Mars. Life (Basel) 2018; 8:life8040056. [PMID: 30400661 PMCID: PMC6315534 DOI: 10.3390/life8040056] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/28/2018] [Accepted: 10/30/2018] [Indexed: 11/16/2022] Open
Abstract
Minerals might have played critical roles for the origin and evolution of possible life forms on Mars. The study of the interactions between the "building blocks of life" and minerals relevant to Mars mineralogy under conditions mimicking the harsh Martian environment may provide key insight into possible prebiotic processes. Therefore, this contribution aims at reviewing the most important investigations carried out so far about the catalytic/protective properties of Martian minerals toward molecular biosignatures under Martian-like conditions. Overall, it turns out that the fate of molecular biosignatures on Mars depends on a delicate balance between multiple preservation and degradation mechanisms, often regulated by minerals, which may take place simultaneously. Such a complexity requires more efforts in simulating realistically the Martian environment in order to better inspect plausible prebiotic pathways and shed light on the nature of the organic compounds detected both in meteorites and on the surface of Mars through in situ analysis.
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Affiliation(s)
- Teresa Fornaro
- Geophysical Laboratory of the Carnegie Institution for Science, 5251 Broad Branch Rd. NW, Washington, DC 20015, USA.
| | - Andrew Steele
- Geophysical Laboratory of the Carnegie Institution for Science, 5251 Broad Branch Rd. NW, Washington, DC 20015, USA.
| | - John Robert Brucato
- INAF-Astrophysical Observatory of Arcetri, L.go E. Fermi 5, 50125 Firenze, Italy.
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76
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Sobron P, Wang A, Mayer DP, Bentz J, Kong F, Zheng M. Dalangtan Saline Playa in a Hyperarid Region of Tibet Plateau: III. Correlated Multiscale Surface Mineralogy and Geochemistry Survey. ASTROBIOLOGY 2018; 18:1277-1304. [PMID: 30095985 DOI: 10.1089/ast.2017.1777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report the first multiscale, systematic field-based testing of correlations between orbital scale advanced spaceborne thermal emission and reflection radiometer visible near-infrared (VNIR)/shortwave infrared (SWIR) reflectance and thermal infrared relative emissivity and outcrop scale Raman spectroscopy, VNIR reflectance, X-ray diffraction (XRD), and laser-induced breakdown spectroscopy (LIBS) mineralogy and chemistry in a saline dry lakebed. This article is one of three reports describing the evolution of salt deposits, meteorological record, and surface and subsurface salt mineralogy in Dalangtan, Qaidam Basin, a hyperarid region of the Tibet Plateau, China, as potential environmental, mineralogical, and biogeochemical analogs to Mars. We have successfully bridged remote sensing data to fine scale mineralogy and chemistry data. We have defined spectral end-members in the northwestern Qaidam Basin and classified areas within the study area on the basis of their spectral similarity to the spectral end-members. Results of VNIR/SWIR classification reveal zonation of spectral units within three large anticlinal domes in the study area that can be correlated between the three structures. Laboratory Raman, VNIR reflectance, XRD, and LIBS data of surface mineral samples collected along a traverse over Xiaoliangshan (XLS) indicate that the surface is dominated by gypsum, Mg sulfates, Na sulfates, halite, and carbonates, with minor concentrations of illite present in most samples as well. Our results can be used as a first step toward better characterizing the potential of orbital reflectance spectroscopy as a method for mineral detection and quantification in salt-rich planetary environments, with the benefit that this technique can be validated on the ground using instruments onboard rovers.
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Affiliation(s)
- Pablo Sobron
- 1 SETI Institute , Mountain View, California
- 2 Impossible Sensing , St. Louis, Missouri
| | - Alian Wang
- 3 Department of Earth and Planetary Sciences and McDonnell Center for Space Sciences, Washington University in St. Louis , St. Louis, Missouri
| | - David P Mayer
- 4 US Geological Survey, Astrogeology Science Center , Flagstaff, Arizona
| | - Jennifer Bentz
- 5 Department of Geological Sciences and Geological Engineering, Queen's University , Kingston, Canada
| | - Fanjing Kong
- 6 Institute of Mineral Resources, Chinese Academy of Geological Sciences, Key Lab of Saline Lake Resources and Enviornments, Ministry of Lands and Resources, Beijing, China
| | - Mianping Zheng
- 6 Institute of Mineral Resources, Chinese Academy of Geological Sciences, Key Lab of Saline Lake Resources and Enviornments, Ministry of Lands and Resources, Beijing, China
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77
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Wang A, Sobron P, Kong F, Zheng M, Zhao YYS. Dalangtan Saline Playa in a Hyperarid Region on Tibet Plateau: II. Preservation of Salts with High Hydration Degrees in Subsurface. ASTROBIOLOGY 2018; 18:1254-1276. [PMID: 30152704 DOI: 10.1089/ast.2018.1829] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Based on a field expedition to the Dalangtan (DLT) saline playa located in a hyperarid region (Qaidam Basin) on the Tibet Plateau and follow-up investigations, we report the mineralogy and geochemistry of the salt layers in two vertical stratigraphic cross sections in the DLT playa. Na-, Ca-, Mg-, KCaMg-sulfates; Na-, K-, KMg-chlorides; mixed (K, Mg)-chloride-sulfate; and chlorate and perchlorate were identified in the collected samples. This mineral assemblage represents the last-stage precipitation products from Na-K-Mg-Ca-Cl-SO4 brine and the oxychlorine formation from photochemistry reaction similar to other hyperarid regions on Earth. The spatial distributions of these salts in both stratigraphic cross sections suggest very limited brine volumes during the precipitation episodes in the Holocene era. More importantly, sulfates and chlorides with a high degree of hydrations were found preserved within the subsurface salt-rich layers of DLT saline playa, where the environmental conditions at the surface are controlled by the hyperaridity in the Qaidam Basin on the Tibet Plateau. Our findings suggest a very different temperature and relative humidity environment maintained by the hydrous salts in a subsurface salty layer, where the climatic conditions at surface have very little or no influence. This observation bears some similarities with four observations on Mars, which implies not only a large humidity reservoir in midlatitude and equatorial regions on Mars but also habitability potential that warrants further investigation.
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Affiliation(s)
- Alian Wang
- 1 Department of Earth and Planetary Sciences, McDonnell Center for Space Sciences, Washington University in St. Louis , St. Louis, Missouri
| | - Pablo Sobron
- 2 SETI Institute , Mountain View, California
- 3 Impossible Sensing , St. Louis, Missouri
| | - Fanjing Kong
- 4 MLR Key Laboratory of Saline Lake Environments and Resources, Institute of Mineral Resources , Chinese Academy of Geological Sciences, Beijing, China
| | - Mianping Zheng
- 4 MLR Key Laboratory of Saline Lake Environments and Resources, Institute of Mineral Resources , Chinese Academy of Geological Sciences, Beijing, China
| | - Yu-Yan Sara Zhao
- 5 Institute of Geochemistry , Chinese Academy of Sciences, Guiyang, China
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78
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Oberlin EA, Claire MW, Kounaves SP. Evaluation of the Tindouf Basin Region in Southern Morocco as an Analogue Site for Soil Geochemistry on Noachian Mars. ASTROBIOLOGY 2018; 18:1318-1328. [PMID: 29424566 DOI: 10.1089/ast.2016.1557] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Locations on Earth that provide insights into processes that may be occurring or may have occurred throughout martian history are often broadly deemed "Mars analog environments." As no single locale can precisely represent a past or present martian environment, it is important to focus on characterization of terrestrial processes that produce analogous features to those observed in specific regions of Mars or, if possible, specific time periods during martian history. Here, we report on the preservation of ionic species in soil samples collected from the Tindouf region of Morocco and compare them with the McMurdo Dry Valleys of Antarctica, the Atacama Desert in Chile, the martian meteorite EETA79001, and the in situ Mars analyses from the Phoenix Wet Chemistry Laboratory (WCL). The Moroccan samples show the greatest similarity with those from Victoria Valley, Beacon Valley, and the Atacama, while being consistently depleted compared to University Valley and enriched compared to Taylor Valley. The NO3/Cl ratios are most similar to Victoria Valley and Atacama, while the SO4/Cl ratios are similar to those from Beacon Valley, Victoria Valley, and the Atacama. While perchlorate concentrations in the Moroccan samples are typically lower than those found in samples of other analog sites, conditions in the region are sufficiently arid to retain oxychlorines at detectable levels. Our results suggest that the Tindouf Basin in Morocco can serve as a suitable analogue for the soil geochemistry and subsequent aridification of the Noachian epoch on Mars.
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Affiliation(s)
| | - Mark W Claire
- 2 School of Earth and Environmental Sciences, University of St Andrews , UK
- 3 Centre for Exoplanet Science, University of St Andrews , UK
- 4 Blue Marble Space Institute of Science , Seattle, Washington, USA
| | - Samuel P Kounaves
- 1 Department of Chemistry, Tufts University , Medford, Massachusetts, USA
- 5 Department of Earth Science and Engineering, Imperial College London , UK
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79
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Huang T, Wang R, Xiao L, Wang H, Martínez JM, Escudero C, Amils R, Cheng Z, Xu Y. Dalangtan Playa (Qaidam Basin, NW China): Its microbial life and physicochemical characteristics and their astrobiological implications. PLoS One 2018; 13:e0200949. [PMID: 30067805 PMCID: PMC6070256 DOI: 10.1371/journal.pone.0200949] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 07/04/2018] [Indexed: 01/29/2023] Open
Abstract
Dalangtan Playa is the second largest salt playa in the Qaidam Basin, north-western China. The hyper saline deposition, extremely arid climate and high UV radiation make Dalangtan a Mars analogue both for geomorphology and life preservation. To better understand microbial life at Dalangtan, both culture-dependent and culture-independent methods were examined and simultaneously, environment conditions and the evaporitic mineral assemblages were investigated. Ten and thirteen subsurface samples were collected along a 595-cm deep profile (P1) and a 685-cm deep profile (P2) respectively, and seven samples were gathered from surface sediments. These samples are composed of salt minerals, minor silicate mineral fragments and clays. The total bacterial cell numbers are (1.54±0.49) ×10(5) g-1 for P1 and (3.22±0.95) ×10(5) g-1 for P2 as indicated by the CAtalyzed Reporter Deposition- Fluorescent in situ Hybridization (CARD-FISH). 76.6% and 75.7% of the bacteria belong to Firmicutes phylum respectively from P1 and P2. In total, 47 bacteria and 6 fungi were isolated from 22 subsurface samples. In contrast, only 3 bacteria and 1 fungus were isolated from 3 surface samples. The isolated bacteria show high homology (≥97%) with members of the Firmicutes phylum (47 strains, 8 genera) and the Actinobacteria phylum (3 strains, 2 genera), which agrees with the result of CARD-FISH. Isolated fungi showed ≥98% ITS1 homology with members of the phylum Ascomycota. Moisture content and TOC values may control the sediments colonization. Given the deliquescence of salts, evaporites may provide refuge for microbial life, which merits further investigation. Halotolerant and spore-forming microorganisms are the dominant microbial groups capable of surviving under extreme conditions. Our results offer brand-new information on microbial biomass in Dalangtan Playa and shed light on understanding the potential microbial life in the dried playa or paleo-lakes on Mars.
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Affiliation(s)
- Ting Huang
- State Key Laboratory of Geological Process and Mineral Resources, Planetary Science Institute, China University of Geosciences, Wuhan, Hubei, China
| | - Ruicheng Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei, China
| | - Long Xiao
- State Key Laboratory of Geological Process and Mineral Resources, Planetary Science Institute, China University of Geosciences, Wuhan, Hubei, China
- Space Science Institute, Macau University of Science and Technology, Macau, China
- * E-mail: (LX); (HW)
| | - Hongmei Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei, China
- * E-mail: (LX); (HW)
| | - José M. Martínez
- Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Madrid, Spain
| | - Cristina Escudero
- Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Madrid, Spain
| | - Ricardo Amils
- Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Madrid, Spain
- Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, Madrid, Spain
| | - Ziye Cheng
- State Key Laboratory of Geological Process and Mineral Resources, Planetary Science Institute, China University of Geosciences, Wuhan, Hubei, China
| | - Yi Xu
- Space Science Institute, Macau University of Science and Technology, Macau, China
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80
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Thompson SP, Kennedy H, Day SJ, Baker AR, Butler BM, Safi E, Kelly J, Male A, Potter J, Cobb T, Murray CA, Tang CC, Evans A, Mercado R. A slow-cooling-rate in situ cell for long-duration studies of mineral precipitation in cold aqueous environments on Earth and other planetary bodies. J Appl Crystallogr 2018; 51:1197-1210. [PMID: 30147638 PMCID: PMC6100201 DOI: 10.1107/s1600576718008816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 06/15/2018] [Indexed: 11/11/2022] Open
Abstract
Liquid oceans and ice caps, along with ice crusts, have long been considered defining features of the Earth, but space missions and observations have shown that they are in fact common features among many of the solar system's outer planets and their satellites. Interactions with rock-forming materials have produced saline oceans not dissimilar in many respects to those on Earth, where mineral precipitation within frozen seawater plays a significant role in both determining global properties and regulating the environment in which a complex ecosystem of extremophiles exists. Since water is considered an essential ingredient for life, the presence of oceans and ice on other solar system bodies is of great astrobiological interest. However, the details surrounding mineral precipitation in freezing environments are still poorly constrained, owing to the difficulties of sampling and ex situ preservation for laboratory analysis, meaning that predictive models have limited empirical underpinnings. To address this, the design and performance characterization of a transmission-geometry sample cell for use in long-duration synchrotron X-ray powder diffraction studies of in situ mineral precipitation from aqueous ice-brine systems are presented. The cell is capable of very slow cooling rates (e.g. 0.3°C per day or less), and its performance is demonstrated with the results from a year-long study of the precipitation of the hydrated magnesium sulfate phase meridianiite (MgSO4·11H2O) from the MgSO4-H2O system. Evidence from the Mars Rover mission suggests that this hydrated phase is widespread on the present-day surface of Mars. However, as well as the predicted hexagonal ice and meridianiite phases, an additional hydrated sulfate phase and a disordered phase are observed.
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Affiliation(s)
- Stephen P. Thompson
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Hilary Kennedy
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey LL59 5AB, UK
| | - Sarah J. Day
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Annabelle R. Baker
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Benjamin M. Butler
- Environmental and Biochemical Sciences, The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK
| | - Emmal Safi
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
- Astrophysics Group, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire ST5 5BG, UK
| | - Jon Kelly
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Andrew Male
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Jonathan Potter
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Tom Cobb
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Claire A. Murray
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Chiu C. Tang
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Aneurin Evans
- Astrophysics Group, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire ST5 5BG, UK
| | - Ronaldo Mercado
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
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81
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Curtis-Harper E, Pearson VK, Summers S, Bridges JC, Schwenzer SP, Olsson-Francis K. The Microbial Community of a Terrestrial Anoxic Inter-Tidal Zone: A Model for Laboratory-Based Studies of Potentially Habitable Ancient Lacustrine Systems on Mars. Microorganisms 2018; 6:microorganisms6030061. [PMID: 29966361 PMCID: PMC6165429 DOI: 10.3390/microorganisms6030061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 06/18/2018] [Accepted: 06/21/2018] [Indexed: 11/16/2022] Open
Abstract
Evidence indicates that Gale crater on Mars harboured a fluvio-lacustrine environment that was subjected to physio-chemical variations such as changes in redox conditions and evaporation with salinity changes, over time. Microbial communities from terrestrial environmental analogues sites are important for studying such potential habitability environments on early Mars, especially in laboratory-based simulation experiments. Traditionally, such studies have predominantly focused on microorganisms from extreme terrestrial environments. These are applicable to a range of Martian environments; however, they lack relevance to the lacustrine systems. In this study, we characterise an anoxic inter-tidal zone as a terrestrial analogue for the Gale crater lake system according to its chemical and physical properties, and its microbiological community. The sub-surface inter-tidal environment of the River Dee estuary, United Kingdom (53°21′15.40″ N, 3°10′24.95″ W) was selected and compared with available data from Early Hesperian-time Gale crater, and temperature, redox, and pH were similar. Compared to subsurface ‘groundwater’-type fluids invoked for the Gale subsurface, salinity was higher at the River Dee site, which are more comparable to increases in salinity that likely occurred as the Gale crater lake evolved. Similarities in clay abundance indicated similar access to, specifically, the bio-essential elements Mg, Fe and K. The River Dee microbial community consisted of taxa that were known to have members that could utilise chemolithoautotrophic and chemoorganoheterotrophic metabolism and such a mixed metabolic capability would potentially have been feasible on Mars. Microorganisms isolated from the site were able to grow under environment conditions that, based on mineralogical data, were similar to that of the Gale crater’s aqueous environment at Yellowknife Bay. Thus, the results from this study suggest that the microbial community from an anoxic inter-tidal zone is a plausible terrestrial analogue for studying habitability of fluvio-lacustrine systems on early Mars, using laboratory-based simulation experiments.
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Affiliation(s)
- Elliot Curtis-Harper
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
| | - Victoria K Pearson
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
| | - Stephen Summers
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore, Singapore.
| | - John C Bridges
- Space Research Centre, Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK.
| | - Susanne P Schwenzer
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
| | - Karen Olsson-Francis
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
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82
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Exploration of Planetary Hyperspectral Images with Unsupervised Spectral Unmixing: A Case Study of Planet Mars. REMOTE SENSING 2018. [DOI: 10.3390/rs10050737] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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83
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Gordon PR, Sephton MA. A Method for Choosing the Best Samples for Mars Sample Return. ASTROBIOLOGY 2018; 18:556-570. [PMID: 29443541 PMCID: PMC5962928 DOI: 10.1089/ast.2017.1744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/29/2017] [Indexed: 06/08/2023]
Abstract
Success of a future Mars Sample Return mission will depend on the correct choice of samples. Pyrolysis-FTIR can be employed as a triage instrument for Mars Sample Return. The technique can thermally dissociate minerals and organic matter for detection. Identification of certain mineral types can determine the habitability of the depositional environment, past or present, while detection of organic matter may suggest past or present habitation. In Mars' history, the Theiikian era represents an attractive target for life search missions and the acquisition of samples. The acidic and increasingly dry Theiikian may have been habitable and followed a lengthy neutral and wet period in Mars' history during which life could have originated and proliferated to achieve relatively abundant levels of biomass with a wide distribution. Moreover, the sulfate minerals produced in the Theiikian are also known to be good preservers of organic matter. We have used pyrolysis-FTIR and samples from a Mars analog ferrous acid stream with a thriving ecosystem to test the triage concept. Pyrolysis-FTIR identified those samples with the greatest probability of habitability and habitation. A three-tier scoring system was developed based on the detection of (i) organic signals, (ii) carbon dioxide and water, and (iii) sulfur dioxide. The presence of each component was given a score of A, B, or C depending on whether the substance had been detected, tentatively detected, or not detected, respectively. Single-step (for greatest possible sensitivity) or multistep (for more diagnostic data) pyrolysis-FTIR methods informed the assignments. The system allowed the highest-priority samples to be categorized as AAA (or A*AA if the organic signal was complex), while the lowest-priority samples could be categorized as CCC. Our methods provide a mechanism with which to rank samples and identify those that should take the highest priority for return to Earth during a Mars Sample Return mission. Key Words: Mars-Astrobiology-Search for Mars' organics-Infrared spectroscopy-Planetary habitability and biosignatures. Astrobiology 18, 556-570.
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Affiliation(s)
- Peter R Gordon
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London , UK
| | - Mark A Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London , UK
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84
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Fox-Powell MG, Cockell CS. Building a Geochemical View of Microbial Salt Tolerance: Halophilic Adaptation of Marinococcus in a Natural Magnesium Sulfate Brine. Front Microbiol 2018; 9:739. [PMID: 29713317 PMCID: PMC5911959 DOI: 10.3389/fmicb.2018.00739] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 03/29/2018] [Indexed: 11/13/2022] Open
Abstract
Current knowledge of life in hypersaline habitats is mostly limited to sodium and chloride-dominated environments. This narrow compositional window does not reflect the diversity of brine environments that exist naturally on Earth and other planetary bodies. Understanding the limits of the microbial biosphere and predicting extraterrestrial habitability demands a systematic effort to characterize ionic specificities of organisms from a representative range of saline habitats. Here, we investigated a strain of Marinococcus isolated from the magnesium and sulfate-dominated Basque Lakes (British Columbia, Canada). This organism was the sole isolate obtained after exposure to exceptionally high levels of Mg2+ and SO42- ions (2.369 and 2.840 M, respectively), and grew at extremes of ionic strength not normally encountered in Na+/Cl- brines (12.141 mol liter-1). Its association at the 16S rDNA level with bacterial halophiles suggests that ancestral halophily has allowed it to adapt to a different saline habitat. Growth was demonstrated in media dominated by NaCl, Na2SO4, MgCl2, and MgSO4, yet despite this plasticity the strain was still restricted; requiring either Na+ or Cl- to maintain short doubling times. Water activity could not explain growth rate differences between media, demonstrating the importance of ionic composition for dictating microbial growth windows. A new framework for understanding growth in brines is required, that accounts for the geochemical history of brines as well as the various stresses that ions impose on microbes. Studies such as this are required to gain a truly universal understanding of the limits of biological ion tolerance.
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Affiliation(s)
- Mark G Fox-Powell
- UK Centre for Astrobiology, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom.,School of Earth and Environmental Sciences, University of St Andrews, St Andrews, United Kingdom
| | - Charles S Cockell
- UK Centre for Astrobiology, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
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85
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Yesiltas M. Investigation of carbonates in the Sutter's Mill meteorite grains with hyperspectral infrared imaging micro-spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 194:92-101. [PMID: 29328955 DOI: 10.1016/j.saa.2018.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 12/25/2017] [Accepted: 01/05/2018] [Indexed: 06/07/2023]
Abstract
Synchrotron-based high spatial resolution hyperspectral infrared imaging technique provides thousands of infrared spectra with high resolution, thus allowing us to acquire detailed spatial maps of chemical molecular structures for many grains in short times. Utilizing this technique, thousands of infrared spectra were analyzed at once instead of inspecting each spectrum separately. Sutter's Mill meteorite is a unique carbonaceous type meteorite with highly heterogeneous chemical composition. Multiple grains from the Sutter's Mill meteorite have been studied using this technique and the presence of both hydrous and anhydrous silicate minerals have been observed. It is observed that the carbonate mineralogy varies from simple to more complex carbonates even within a few microns in the meteorite grains. These variations, the type and distribution of calcite-like vs. dolomite-like carbonates are presented by means of hyperspectral FTIR imaging spectroscopy with high resolution. Various scenarios for the formation of different carbonate compositions in the Sutter's Mill parent body are discussed.
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Affiliation(s)
- Mehmet Yesiltas
- Faculty of Aeronautics and Space Sciences, Kirklareli University, Kirklareli 39000, Turkey.
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86
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Shkolyar S, Eshelman EJ, Farmer JD, Hamilton D, Daly MG, Youngbull C. Detecting Kerogen as a Biosignature Using Colocated UV Time-Gated Raman and Fluorescence Spectroscopy. ASTROBIOLOGY 2018; 18:431-453. [PMID: 29624103 DOI: 10.1089/ast.2017.1716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Mars 2020 mission will analyze samples in situ and identify any that could have preserved biosignatures in ancient habitable environments for later return to Earth. Highest priority targeted samples include aqueously formed sedimentary lithologies. On Earth, such lithologies can contain fossil biosignatures as aromatic carbon (kerogen). In this study, we analyzed nonextracted kerogen in a diverse suite of natural, complex samples using colocated UV excitation (266 nm) time-gated (UV-TG) Raman and laser-induced fluorescence spectroscopies. We interrogated kerogen and its host matrix in samples to (1) explore the capabilities of UV-TG Raman and fluorescence spectroscopies for detecting kerogen in high-priority targets in the search for possible biosignatures on Mars; (2) assess the effectiveness of time gating and UV laser wavelength in reducing fluorescence in Raman spectra; and (3) identify sample-specific issues that could challenge rover-based identifications of kerogen using UV-TG Raman spectroscopy. We found that ungated UV Raman spectroscopy is suited to identify diagnostic kerogen Raman bands without interfering fluorescence and that UV fluorescence spectroscopy is suited to identify kerogen. These results highlight the value of combining colocated Raman and fluorescence spectroscopies, similar to those obtainable by SHERLOC on Mars 2020, to strengthen the confidence of kerogen detection as a potential biosignature in complex natural samples. Key Words: Raman spectroscopy-Laser-induced fluorescence spectroscopy-Mars Sample Return-Mars 2020 mission-Kerogen-Biosignatures. Astrobiology 18, 431-453.
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Affiliation(s)
- Svetlana Shkolyar
- 1 School of Earth and Space Exploration, Arizona State University , Tempe, Arizona
- 2 Current address: Geophysical Laboratory, Carnegie Institution of Washington , Washington, District of Columbia
| | - Evan J Eshelman
- 3 The Centre for Research in Earth and Space Science (CRESS), York University , Toronto, Ontario, Canada
| | - Jack D Farmer
- 1 School of Earth and Space Exploration, Arizona State University , Tempe, Arizona
| | - David Hamilton
- 3 The Centre for Research in Earth and Space Science (CRESS), York University , Toronto, Ontario, Canada
| | - Michael G Daly
- 3 The Centre for Research in Earth and Space Science (CRESS), York University , Toronto, Ontario, Canada
| | - Cody Youngbull
- 4 Flathead Lake Biological Station, University of Montana , Polson, Montana
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87
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Lewis JM, Najorka J, Watson JS, Sephton MA. The Search for Hesperian Organic Matter on Mars: Pyrolysis Studies of Sediments Rich in Sulfur and Iron. ASTROBIOLOGY 2018; 18:454-464. [PMID: 29298093 PMCID: PMC5910044 DOI: 10.1089/ast.2017.1717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/06/2017] [Indexed: 05/21/2023]
Abstract
Jarosite on Mars is of significant geological and astrobiological interest, as it forms in acidic aqueous conditions that are potentially habitable for acidophilic organisms. Jarosite can provide environmental context and may host organic matter. The most common extraction technique used to search for organic compounds on the surface of Mars is pyrolysis. However, thermal decomposition of jarosite releases oxygen into pyrolysis ovens, which degrades organic signals. Jarosite has a close association with the iron oxyhydroxide goethite in many depositional/diagenetic environments. Hematite can form by dehydration of goethite or directly from jarosite under certain aqueous conditions. Goethite and hematite are significantly more amenable than jarosite for pyrolysis experiments employed to search for organic matter. Analysis of the mineralogy and organic chemistry of samples from a natural acidic stream revealed a diverse response for organic compounds during pyrolysis of goethite-rich layers but a poor response for jarosite-rich or mixed jarosite-goethite samples. Goethite units that are associated with jarosite, but do not contain jarosite themselves, should be targeted for organic detection pyrolysis experiments on Mars. These findings are extremely timely, as exploration targets for Mars Science Laboratory include Vera Rubin Ridge (formerly known as "Hematite Ridge"), which may have formed from goethite precursors. Key Words: Mars-Pyrolysis-Jarosite-Goethite-Hematite-Biosignatures. Astrobiology 18, 454-464.
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Affiliation(s)
- James M.T. Lewis
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Jens Najorka
- Impacts and Astromaterials Research Centre, Department of Mineralogy, Natural History Museum, London, UK
| | - Jonathan S. Watson
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Mark A. Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, UK
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88
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Price A, Pearson VK, Schwenzer SP, Miot J, Olsson-Francis K. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism. Front Microbiol 2018; 9:513. [PMID: 29616015 PMCID: PMC5869265 DOI: 10.3389/fmicb.2018.00513] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 03/06/2018] [Indexed: 11/13/2022] Open
Abstract
This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1-3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate instrumentation.
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Affiliation(s)
- Alex Price
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, United Kingdom
| | - Victoria K. Pearson
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, United Kingdom
| | - Susanne P. Schwenzer
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, United Kingdom
| | - Jennyfer Miot
- CNRS, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Muséum National d’Histoire Naturelle, Université Pierre et Marie Curie – Sorbonne Universités, UMR 7590, Paris, France
| | - Karen Olsson-Francis
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, United Kingdom
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89
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Peretyazhko TS, Niles PB, Sutter B, Morris RV, Agresti DG, Le L, Ming DW. Smectite formation in the presence of sulfuric acid: Implications for acidic smectite formation on early Mars. GEOCHIMICA ET COSMOCHIMICA ACTA 2018; 220:248-260. [PMID: 32801388 PMCID: PMC7427815 DOI: 10.1016/j.gca.2017.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The excess of orbital detection of smectite deposits compared to carbonate deposits on the martian surface presents an enigma because smectite and carbonate formations are both favored alteration products of basalt under neutral to alkaline conditions. We propose that Mars experienced acidic events caused by sulfuric acid (H2SO4) that permitted phyllosilicate, but inhibited carbonate, formation. To experimentally verify this hypothesis, we report the first synthesis of smectite from Mars-analogue glass-rich basalt simulant (66 wt% glass, 32 wt% olivine, 2 wt% chromite) in the presence of H2SO4 under hydrothermal conditions (~200 °C). Smectites were analyzed by X-ray diffraction, Mossbauer spectroscopy, visible and near-infrared reflectance spectroscopy and electron microprobe to characterize mineralogy and chemical composition. Solution chemistry was determined by Inductively Coupled Plasma Mass Spectrometry. Basalt simulant suspensions in 11-42 mM H2SO4 were acidic with pH ≤ 2 at the beginning of incubation and varied from acidic (pH 1.8) to mildly alkaline (pH 8.4) at the end of incubation. Alteration of glass phase during reaction of the basalt simulant with H2SO4 led to formation of the dioctahedral smectite at final pH ~3 and trioctahedral smectite saponite at final pH ~4 and higher. Anhydrite and hematite formed in the final pH range from 1.8 to 8.4 while natroalunite was detected at pH 1.8. Hematite was precipitated as a result of oxidative dissolution of olivine present in Adirondack basalt simulant. Formation of secondary phases, including smectite, resulted in release of variable amounts of Si, Mg, Na and Ca while solubilization of Al and Fe was low. Comparison of mineralogical and solution chemistry data indicated that the type of smectite (i.e., dioctahedral vs trioctahedral) was likely controlled by Mg leaching from altering basalt and substantial Mg loss created favorable conditions for formation of dioctahedral smectite. We present a model for global-scale smectite formation on Mars via acid-sulfate conditions created by the volcanic outgassing of SO2 in the Noachian and early Hesperian.
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Affiliation(s)
| | - P B Niles
- NASA Johnson Space Center, Houston, TX 77058
| | - B Sutter
- Jacobs, NASA Johnson Space Center, Houston, TX 77058
| | - R V Morris
- NASA Johnson Space Center, Houston, TX 77058
| | - D G Agresti
- University of Alabama at Birmingham, Birmingham, AL 35294
| | - L Le
- Jacobs, NASA Johnson Space Center, Houston, TX 77058
| | - D W Ming
- NASA Johnson Space Center, Houston, TX 77058
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90
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Cabrol NA. The Coevolution of Life and Environment on Mars: An Ecosystem Perspective on the Robotic Exploration of Biosignatures. ASTROBIOLOGY 2018; 18:1-27. [PMID: 29252008 PMCID: PMC5779243 DOI: 10.1089/ast.2017.1756] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/27/2017] [Indexed: 05/09/2023]
Abstract
Earth's biological and environmental evolution are intertwined and inseparable. This coevolution has become a fundamental concept in astrobiology and is key to the search for life beyond our planet. In the case of Mars, whether a coevolution took place is unknown, but analyzing the factors at play shows the uniqueness of each planetary experiment regardless of similarities. Early Earth and early Mars shared traits. However, biological processes on Mars, if any, would have had to proceed within the distinctive context of an irreversible atmospheric collapse, greater climate variability, and specific planetary characteristics. In that, Mars is an important test bed for comparing the effects of a unique set of spatiotemporal changes on an Earth-like, yet different, planet. Many questions remain unanswered about Mars' early environment. Nevertheless, existing data sets provide a foundation for an intellectual framework where notional coevolution models can be explored. In this framework, the focus is shifted from planetary-scale habitability to the prospect of habitats, microbial ecotones, pathways to biological dispersal, biomass repositories, and their meaning for exploration. Critically, as we search for biosignatures, this focus demonstrates the importance of starting to think of early Mars as a biosphere and vigorously integrating an ecosystem approach to landing site selection and exploration. Key Words: Astrobiology-Biosignatures-Coevolution of Earth and life-Mars. Astrobiology 18, 1-27.
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91
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Dalai P, Pleyer HL, Strasdeit H, Fox S. The Influence of Mineral Matrices on the Thermal Behavior of Glycine. ORIGINS LIFE EVOL B 2017; 47:427-452. [PMID: 27757771 DOI: 10.1007/s11084-016-9523-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 08/27/2016] [Indexed: 10/20/2022]
Abstract
On the Hadean-Early Archean Earth, the first islands must have provided hot and dry environments for abiotically formed organic molecules. The heat sources, mainly volcanism and meteorite impacts, were also available on Mars during the Noachian period. In recent work simulating this scenario, we have shown that neat glycine forms a black, sparingly water-soluble polymer ("thermomelanoid") when dry-heated at 200 °C under pure nitrogen. The present study explores whether relevant minerals and mineral mixtures can change this thermal behavior. Most experiments were conducted at 200 or 250 °C for 2 or 7 days. The mineral matrices used were phyllosilicates (Ca-montmorillonites SAz-1 and STx-1, Na-montmorillonite SAz-1-Na, nontronite NAu-1, kaolinite KGa-1), salts (NaCl, NaCl-KCl, CaCl2, artificial sea salt, gypsum, magnesite), picritic basalt, and three Martian regolith simulants (P-MRS, S-MRS, JSC Mars-1A). The main analytical method employed was high-performance liquid chromatography (HPLC). Glycine intercalated in SAz-1 and SAz-1-Na was well protected against thermomelanoid formation and sublimation at 200 °C: after 2 days, 95 and 79 %, respectively, had either survived unaltered or been transformed into the cyclic dipeptide (DKP) and linear peptides up to Gly6. The glycine survival rate followed the order SAz-1 > SAz-1-Na > STx-1 ≈ NAu-1 > KGa-1. Very good protection was also provided by artificial sea salt (84 % unaltered glycine after 200 °C for 7 days). P-MRS promoted the condensation up to Gly6, consistent with its high phyllosilicate content. The remaining matrices were less effective in preserving glycine as such or as peptides.
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Affiliation(s)
- Punam Dalai
- Department of Bioinorganic Chemistry, Institute of Chemistry, University of Hohenheim, Garbenstr. 30, 70599, Stuttgart, Germany
| | - Hannes Lukas Pleyer
- Department of Bioinorganic Chemistry, Institute of Chemistry, University of Hohenheim, Garbenstr. 30, 70599, Stuttgart, Germany
| | - Henry Strasdeit
- Department of Bioinorganic Chemistry, Institute of Chemistry, University of Hohenheim, Garbenstr. 30, 70599, Stuttgart, Germany.
| | - Stefan Fox
- Department of Bioinorganic Chemistry, Institute of Chemistry, University of Hohenheim, Garbenstr. 30, 70599, Stuttgart, Germany
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92
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McKay CP, Andersen D, Davila A. Antarctic environments as models of planetary habitats: University Valley as a model for modern Mars and Lake Untersee as a model for Enceladus and ancient Mars. ACTA ACUST UNITED AC 2017. [DOI: 10.1080/2154896x.2017.1383705] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | - Dale Andersen
- Carl Sagan Center, SETI Institute, Mountain View, CA, USA
| | - Alfonso Davila
- Space Science Division, NASA Ames Research Center, Mountain View, CA, USA
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93
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Amador ES, Bandfield JL, Brazelton WJ, Kelley D. The Lost City Hydrothermal Field: A Spectroscopic and Astrobiological Analogue for Nili Fossae, Mars. ASTROBIOLOGY 2017; 17:1138-1160. [PMID: 28910143 DOI: 10.1089/ast.2016.1606] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Low-temperature serpentinization is a critical process with respect to Earth's habitability and the Solar System. Exothermic serpentinization reactions commonly produce hydrogen as a direct by-product and typically produce short-chained organic compounds indirectly. Here, we present the spectral and mineralogical variability in rocks from the serpentine-driven Lost City Hydrothermal Field on Earth and the olivine-rich region of Nili Fossae on Mars. Near- and thermal-infrared spectral measurements were made from a suite of Lost City rocks at wavelengths similar to those for instruments collecting measurements of the martian surface. Results from Lost City show a spectrally distinguishable suite of Mg-rich serpentine, Ca carbonates, talc, and amphibole minerals. Aggregated detections of low-grade metamorphic minerals in rocks from Nili Fossae were mapped and yielded a previously undetected serpentine exposure in the region. Direct comparison of the two spectral suites indicates similar mineralogy at both Lost City and in the Noachian (4-3.7 Ga) bedrock of Nili Fossae, Mars. Based on mapping of these spectral phases, the implied mineralogical suite appears to be extensive across the region. These results suggest that serpentinization was once an active process, indicating that water and energy sources were available, as well as a means for prebiotic chemistry during a time period when life was first emerging on Earth. Although the mineralogical assemblages identified on Mars are unlikely to be directly analogous to rocks that underlie the Lost City Hydrothermal Field, related geochemical processes (and associated sources of biologically accessible energy) were once present in the subsurface, making Nili Fossae a compelling candidate for a once-habitable environment on Mars. Key Words: Mars-Habitability-Serpentinization-Analogue. Astrobiology 17, 1138-1160.
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Affiliation(s)
- Elena S Amador
- 1 Department of Earth and Space Sciences, University of Washington , Seattle, Washington
| | | | | | - Deborah Kelley
- 4 School of Oceanography, University of Washington , Seattle, Washington
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94
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Abstract
Spectral remote sensing in the visible/near-infrared (VNIR) and mid-IR (MIR) regions has enabled detection and characterisation of multiple clays and clay minerals on Earth and in the Solar System. Remote sensing on Earth poses the greatest challenge due to atmospheric absorptions that interfere with detection of surface minerals. Still, a greater variety of clay minerals have been observed on Earth than other bodies due to extensive aqueous alteration on our planet. Clay minerals have arguably been mapped in more detail on the planet Mars because they are not masked by vegetation on that planet and the atmosphere is less of a hindrance. Fe/Mg-smectite is the most abundant clay mineral on the surface of Mars and is also common in meteorites and comets where clay minerals are detected.
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Affiliation(s)
- Janice L Bishop
- SETI Institute, Carl Sagan Center, 189 Bernardo Ave, Suite 200, Mountain View, CA 94043, USA
| | | | - John Carter
- Institut d'Astrophysique Spatiale, CNRS/Paris-Sud University, Orsay, France
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95
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Kölbl D, Pignitter M, Somoza V, Schimak MP, Strbak O, Blazevic A, Milojevic T. Exploring Fingerprints of the Extreme Thermoacidophile Metallosphaera sedula Grown on Synthetic Martian Regolith Materials as the Sole Energy Sources. Front Microbiol 2017; 8:1918. [PMID: 29062303 PMCID: PMC5640722 DOI: 10.3389/fmicb.2017.01918] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 09/20/2017] [Indexed: 12/04/2022] Open
Abstract
The biology of metal transforming microorganisms is of a fundamental and applied importance for our understanding of past and present biogeochemical processes on Earth and in the Universe. The extreme thermoacidophile Metallosphaera sedula is a metal mobilizing archaeon, which thrives in hot acid environments (optimal growth at 74°C and pH 2.0) and utilizes energy from the oxidation of reduced metal inorganic sources. These characteristics of M. sedula make it an ideal organism to further our knowledge of the biogeochemical processes of possible life on extraterrestrial planetary bodies. Exploring the viability and metal extraction capacity of M. sedula living on and interacting with synthetic extraterrestrial minerals, we show that M. sedula utilizes metals trapped in the Martian regolith simulants (JSC Mars 1A; P-MRS; S-MRS; MRS07/52) as the sole energy sources. The obtained set of microbiological and mineralogical data suggests that M. sedula actively colonizes synthetic Martian regolith materials and releases free soluble metals. The surface of bioprocessed Martian regolith simulants is analyzed for specific mineralogical fingerprints left upon M. sedula growth. The obtained results provide insights of biomining of extraterrestrial material as well as of the detection of biosignatures implementing in life search missions.
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Affiliation(s)
- Denise Kölbl
- Extremophiles Group, Department of Biophysical Chemistry, University of Vienna, Vienna, Austria
| | - Marc Pignitter
- Department of Nutritional and Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Veronika Somoza
- Department of Nutritional and Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Mario P Schimak
- Department of Symbiosis, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Oliver Strbak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Amir Blazevic
- Extremophiles Group, Department of Biophysical Chemistry, University of Vienna, Vienna, Austria
| | - Tetyana Milojevic
- Extremophiles Group, Department of Biophysical Chemistry, University of Vienna, Vienna, Austria
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96
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Olsson-Francis K, Pearson VK, Steer ED, Schwenzer SP. Determination of Geochemical Bio-Signatures in Mars-Like Basaltic Environments. Front Microbiol 2017; 8:1668. [PMID: 28943863 PMCID: PMC5596621 DOI: 10.3389/fmicb.2017.01668] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 08/17/2017] [Indexed: 11/28/2022] Open
Abstract
Bio-signatures play a central role in determining whether life existed on early Mars. Using a terrestrial basalt as a compositional analog for the martian surface, we applied a combination of experimental microbiology and thermochemical modeling techniques to identify potential geochemical bio-signatures for life on early Mars. Laboratory experiments were used to determine the short-term effects of biota on the dissolution of terrestrial basalt, and the formation of secondary alteration minerals. The chemoorganoheterotrophic bacterium, Burkholderia sp. strain B_33, was grown in a minimal growth medium with and without terrestrial basalt as the sole nutrient source. No growth was detected in the absence of the basalt. In the presence of basalt, during exponential growth, the pH decreased rapidly from pH 7.0 to 3.6 and then gradually increased to a steady-state of equilibrium of between 6.8 and 7.1. Microbial growth coincided with an increase in key elements in the growth medium (Si, K, Ca, Mg, and Fe). Experimental results were compared with theoretical thermochemical modeling to predict growth of secondary alteration minerals, which can be used as bio-signatures, over a geological timescale. We thermochemically modeled the dissolution of the basalt (in the absence of biota) in very dilute brine at 25°C, 1 bar; the pH was buffered by the mineral dissolution and precipitation reactions. Preliminary results suggested that at the water to rock ratio of 1 × 107, zeolite, hematite, chlorite, kaolinite, and apatite formed abiotically. The biotic weathering processes were modeled by varying the pH conditions within the model to adjust for biologic influence. The results suggested that, for a basaltic system, the microbially-mediated dissolution of basalt would result in “simpler” secondary alteration, consisting of Fe-hydroxide and kaolinite, under conditions where the abiotic system would also form chlorite. The results from this study demonstrate that, by using laboratory-based experiments and thermochemical modeling, it is possible to identify secondary alteration minerals that could potentially be used to distinguish between abiotic and biotic weathering processes on early Mars. This work will contribute to the interpretation of data from past, present, and future life detection missions to Mars.
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Affiliation(s)
- Karen Olsson-Francis
- School of Environment, Earth and Ecosystem Sciences, Open UniversityMilton Keynes, United Kingdom
| | - Victoria K Pearson
- School of Physical Sciences, Open UniversityMilton Keynes, United Kingdom
| | - Elisabeth D Steer
- School of Physical Sciences, Open UniversityMilton Keynes, United Kingdom.,Nanoscale and Microscale Research Centre, University of NottinghamNottingham, United Kingdom
| | - Susanne P Schwenzer
- School of Environment, Earth and Ecosystem Sciences, Open UniversityMilton Keynes, United Kingdom
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97
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Fairén AG, Gil‐Lozano C, Uceda ER, Losa‐Adams E, Davila AF, Gago‐Duport L. Mineral paragenesis on Mars: The roles of reactive surface area and diffusion. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2017; 122:1855-1879. [PMID: 29104844 PMCID: PMC5656915 DOI: 10.1002/2016je005229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 08/13/2017] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
Geochemical models of secondary mineral precipitation on Mars generally assume semiopen systems (open to the atmosphere but closed at the water-sediment interface) and equilibrium conditions. However, in natural multicomponent systems, the reactive surface area of primary minerals controls the dissolution rate and affects the precipitation sequences of secondary phases, and simultaneously, the transport of dissolved species may occur through the atmosphere-water and water-sediment interfaces. Here we present a suite of geochemical models designed to analyze the formation of secondary minerals in basaltic sediments on Mars, evaluating the role of (i) reactive surface areas and (ii) the transport of ions through a basalt sediment column. We consider fully open conditions, both to the atmosphere and to the sediment, and a kinetic approach for mineral dissolution and precipitation. Our models consider a geochemical scenario constituted by a basin (i.e., a shallow lake) where supersaturation is generated by evaporation/cooling and the starting point is a solution in equilibrium with basaltic sediments. Our results show that cation removal by diffusion, along with the input of atmospheric volatiles and the influence of the reactive surface area of primary minerals, plays a central role in the evolution of the secondary mineral sequences formed. We conclude that precipitation of evaporites finds more restrictions in basaltic sediments of small grain size than in basaltic sediments of greater grain size.
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Affiliation(s)
- Alberto G. Fairén
- Centro de Astrobiología (CSIC‐INTA)MadridSpain
- Department of AstronomyCornell UniversityIthacaNew YorkUSA
| | | | - Esther R. Uceda
- Facultad de CienciasUniversidad Autónoma de MadridMadridSpain
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98
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Vago JL, Westall F. Habitability on Early Mars and the Search for Biosignatures with the ExoMars Rover. ASTROBIOLOGY 2017; 17:471-510. [PMID: 31067287 PMCID: PMC5685153 DOI: 10.1089/ast.2016.1533] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 03/05/2017] [Indexed: 05/19/2023]
Abstract
The second ExoMars mission will be launched in 2020 to target an ancient location interpreted to have strong potential for past habitability and for preserving physical and chemical biosignatures (as well as abiotic/prebiotic organics). The mission will deliver a lander with instruments for atmospheric and geophysical investigations and a rover tasked with searching for signs of extinct life. The ExoMars rover will be equipped with a drill to collect material from outcrops and at depth down to 2 m. This subsurface sampling capability will provide the best chance yet to gain access to chemical biosignatures. Using the powerful Pasteur payload instruments, the ExoMars science team will conduct a holistic search for traces of life and seek corroborating geological context information. Key Words: Biosignatures-ExoMars-Landing sites-Mars rover-Search for life. Astrobiology 17, 471-510.
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99
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Hurowitz JA, Grotzinger JP, Fischer WW, McLennan SM, Milliken RE, Stein N, Vasavada AR, Blake DF, Dehouck E, Eigenbrode JL, Fairén AG, Frydenvang J, Gellert R, Grant JA, Gupta S, Herkenhoff KE, Ming DW, Rampe EB, Schmidt ME, Siebach KL, Stack-Morgan K, Sumner DY, Wiens RC. Redox stratification of an ancient lake in Gale crater, Mars. Science 2017; 356:356/6341/eaah6849. [PMID: 28572336 DOI: 10.1126/science.aah6849] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 04/19/2017] [Indexed: 11/02/2022]
Abstract
In 2012, NASA's Curiosity rover landed on Mars to assess its potential as a habitat for past life and investigate the paleoclimate record preserved by sedimentary rocks inside the ~150-kilometer-diameter Gale impact crater. Geological reconstructions from Curiosity rover data have revealed an ancient, habitable lake environment fed by rivers draining into the crater. We synthesize geochemical and mineralogical data from lake-bed mudstones collected during the first 1300 martian solar days of rover operations in Gale. We present evidence for lake redox stratification, established by depth-dependent variations in atmospheric oxidant and dissolved-solute concentrations. Paleoclimate proxy data indicate that a transition from colder to warmer climate conditions is preserved in the stratigraphy. Finally, a late phase of geochemical modification by saline fluids is recognized.
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Affiliation(s)
- J A Hurowitz
- Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, USA.
| | - J P Grotzinger
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - W W Fischer
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - S M McLennan
- Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, USA
| | - R E Milliken
- Department of Geological Sciences, Brown University, Providence, RI 02912, USA
| | - N Stein
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - A R Vasavada
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - D F Blake
- Department of Space Sciences, NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - E Dehouck
- Institut de Recherche en Astrophysique et Planétologie, University Paul Sabatier, 31028 Toulouse, France
| | - J L Eigenbrode
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - A G Fairén
- Centro de Astrobiología, Consejo Superior de Investigaciones Científicas-Instituto Nacional de Técnica Aeroespacial (CSIC-INTA), 28850 Madrid, Spain.,Department of Astronomy, Cornell University, Ithaca, NY 14853, USA
| | - J Frydenvang
- Space Remote Sensing, Los Alamos National Laboratory, Los Alamos, NM 87544, USA.,University of Copenhagen, 1350 Copenhagen, Denmark
| | - R Gellert
- Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - J A Grant
- Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC 20560, USA
| | - S Gupta
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
| | | | - D W Ming
- Astromaterials Research and Exploration Science Division, NASA Johnson Space Center, Houston, TX 77058, USA
| | - E B Rampe
- NASA Johnson Space Center, Houston, TX 77058, USA
| | - M E Schmidt
- Department of Earth Sciences, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - K L Siebach
- Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, USA.,Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - K Stack-Morgan
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - D Y Sumner
- Department of Earth and Planetary Sciences, University of California-Davis, Davis, CA 95616, USA
| | - R C Wiens
- Space Remote Sensing, Los Alamos National Laboratory, Los Alamos, NM 87544, USA
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100
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Chojnacki M, Urso A, Fenton LK, Michaels TI. Aeolian dune sediment flux heterogeneity in Meridiani Planum, Mars. AEOLIAN RESEARCH 2017; 26:73-88. [PMID: 29576818 PMCID: PMC5863747 DOI: 10.1016/j.aeolia.2016.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
It is now known unambiguously that wind-driven bedform activity is occurring on the surface of Mars today, including early detections of active sand dunes in Meridiani Planum's Endeavour crater. Many of these reports are only based on a few sets of observations of relatively isolated bedforms and lack regional context. Here, we investigate aeolian activity across central Meridiani Planum and test the hypothesis that dune sites surrounding Endeavour crater are also active and part of region-wide sediment migration driven by northwesterly winds. All 13 dune fields investigated clearly showed evidence for activity and the majority exhibited dune migration (average rates of 0.6 m/Earth-year). Observations indicate substantial geographic and temporal heterogeneity of dune crest fluxes across the area and per site. Locations with multiple time steps indicate dune sand fluxes can vary by a factor of five, providing evidence for short periods of rapid migration followed by near-stagnation. In contrast, measurements at other sites are nearly identical, indicating that some dunes are in a steady-state as they migrate. The observed sediment transport direction was consistent with a regional northeasterly-to-northwesterly wind regime, revealing more variations than were appreciated from earlier, more localized studies. Craters containing shallow, degraded, flat-floored interiors tended to have dunes with high sediment fluxes/activity, whereas local kilometer-scale topographic obstructions (e.g., central peaks, yardangs) were found to be inversely correlated with dune mobility. Finally, the previous, more limited detections of dune activity in Endeavour crater have been shown to be representative of a broader, region-wide pattern of dune motion.
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Affiliation(s)
- Matthew Chojnacki
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
- Corresponding author at: Lunar and Planetary Lab, University of Arizona, 1541 E. University Blvd, Tucson, AZ 85721-0063, USA. (M. Chojnacki)
| | - Anna Urso
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - Lori K. Fenton
- Carl Sagan Center at the SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043, USA
| | - Timothy I. Michaels
- Carl Sagan Center at the SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043, USA
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