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51. Atacama Rover Astrobiology Drilling Studies Project: Second Year

Author

Glass, B., primary, Davila, A., additional, Parro, V., additional, Quinn, R., additional, Willis, P., additional, Brinckherhoff, W., additional, Zacny, K., additional, DiRuggiero, J., additional, Williams, M., additional, Fong, T., additional, Bergman, D., additional, Stucky, T., additional, Seitz, S., additional, Paulsen, G., additional, McKay, C., additional, and Stoker, C., additional

Published
2018
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52. Microbial metabolism of Tholin

Author

Stoker, C. R, Mancinelli, R. L, Boston, P. J, Segal, W, and Khare, B. N

Subjects
Life Sciences (General)
Abstract

Tholin, a class of complex organic heteropolymers hypothesized to possess wide solar system distribution, is shown to furnish the carbon and energy requirements of a wide variety of common soil bacteria which encompasses aerobic, anaerobic, and facultatively anaerobic bacteria. Some of these bacteria are able to derive not merely their carbon but also their nitrogen requirements from tholin. The palatability of tholins to modern microbes is speculated to have implications for the early evolution of microbial life on earth; tholins may have formed the base of the food chain for an early heterotrophic biosphere, prior to the evolution of autotrophy on the early earth.

Published
1990
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55. Jasmonate signalling drives time-of-day differences in susceptibility of Arabidopsis to the fungal pathogen Botrytis cinerea

Author

Ingle, R.A., Stoker, C., Stone, W., Adams, N., Smith, R.W., Grant, M., Carré, I., Roden, L.C., and Denby, K.J.

Subjects
Systeem en Synthetische Biologie, disease resistance, Arabidopsis thaliana, plant-pathogen interaction, fungi, food and beverages, defence response, jasmonate, Botrytis cinerea, circadian clock, Systems and Synthetic Biology, defence gene expression, VLAG
Abstract

The circadian clock, an internal timekeeping mechanism, allows plants to anticipate regular changes in the environment, such as light and dark, and biotic challenges such as pathogens and herbivores. Here, we demonstrate that the plant circadian clock influences susceptibility to the necrotrophic fungal pathogen, Botrytis cinerea. Arabidopsis plants show differential susceptibility to B. cinerea depending on the time of day of inoculation. Decreased susceptibility after inoculation at dawn compared to night persists under constant light conditions and is disrupted in dysfunctional clock mutants, demonstrating the role of the plant clock in driving time-of-day susceptibility to B. cinerea. The decreased susceptibility to B. cinerea following inoculation at subjective dawn was associated with faster transcriptional reprogramming of the defence response with gating of infection-responsive genes apparent. Direct target genes of core clock regulators were enriched among the transcription factors that responded more rapidly to infection at subjective dawn than subjective night, suggesting an influence of the clock on the defence-signalling network. In addition, jasmonate signalling plays a crucial role in the rhythmic susceptibility of Arabidopsis to B. cinerea with the enhanced susceptibility to this pathogen at subjective night lost in a jaz6 mutant.

Published
2015

57. Field astrobiology research instruments and methods in moon-mars analogue site

Author

Foing, B.H., Stoker, C., Zavaleta, J., Ehrenfreund, P., Sarrazin, P., Blake, D., Page, J., Pletser, V., Hendrikse, J., Oliveira Lebre Direito, M.S., Kotler, M., Martins, Z., Orzechowska, G., Thiel, C.S., Clarke, J., Gross, J., Wendt, L., Borst, A., Peters, S., Wilhelm, M.-B., Davies, G.R., EuroGeoMars 2009 Team, ILEWG, Petrology, Student Lab and Education, Molecular Cell Physiology, and AIMMS

Abstract

We describe the field demonstration of astrobiology instruments and research methods conducted in and from the Mars Desert Research Station (MDRS) in Utah during the EuroGeoMars campaign 2009 coordinated by ILEWG, ESA/ESTEC and NASA Ames, with the contribution of academic partners. We discuss the entire experimental approach from determining the geological context using remote sensing, in situ measurements, sorties with sample collection and characterization, analysis in the field laboratory, to the post sample analysis using advanced laboratory facilities. We present the rationale for terrestrial field campaigns to strengthen astrobiology research and the link between in situ and orbital remote sensing data. These campaigns are supporting the preparation for future missions such as Mars Science Laboratory, ExoMars or Mars Sample Return. We describe the EuroGeoMars 2009 campaign conducted by MDRS crew 76 and 77, focused on the investigation of surface processes in their geological context. Special emphasis was placed on sample collection and pre-screening using in-situ portable instruments. Science investigations included geological and geochemical measurements as well as detection and diagnostic of water, oxidants, organic matter, minerals, volatiles and biota. EuroGeoMars 2009 was an example of a Moon-Mars field research campaign dedicated to the demonstration of astrobiology instruments and a specific methodology of comprehensive measurements from selected sampling sites. We discuss in sequence: the campaign objectives and trade-off based on science, technical or operational constraints. This includes remote sensing data and maps, and geological context; the monitoring of environmental parameters; the geophysical context and mineralogy studies; geology and geomorphology investigations; geochemistry characterization and subsurface studies. We describe sample handling (extraction and collection) methods, and the sample analysis of soils and rocks performed in the MDRS laboratory using close inspection, initial petrological characterization, microscopy, Visible-NIR spectrometry, Raman spectrometry, X-ray diffraction/X-ray fluorescence spectrometry, soil analysis, electrochemical and biological measurements. The results from post-mission analysis of returned samples using advanced facilities in collaborator institutes are described in companion papers in this issue. We present examples of in-situ analysis, and describe an example investigation on the exploration and analysis of endolithic microbial mats (from reconnaissance, in-situ imaging, sampling, local analysis to post-mission sample analysis). © 2011 Cambridge University Press.

Published
2011

58. Astrobiology field research in Moon/Mars Analogue

Author

Foing, B.H., Stoker, C., Ehrenfreund, P., Petrology, and Student Lab and Education

Abstract

Extreme environments on Earth often provide similar terrain conditions to landing/operation sites on Moon and Mars. Several field campaigns (EuroGeoMars2009 and DOMMEX/ILEWG EuroMoonMars from November 2009 to March 2010) were conducted at the Mars Desert Research Station (MDRS) in Utah. Some of the key astrobiology results are presented in this special issue on 'Astrobiology field research in Moon/Mars analogue environments' relevant to investigate the link between geology, minerals, organics and biota. Preliminary results from a multidisciplinary field campaign at Rio Tinto in Spain are presented. © 2011 Cambridge University Press.

Published
2011

60. H20 at the Phoenix Landing Site

Author

Smith, P.H., Tamppari, L.K., Arvidson, R.E., Bass, D., Blaney, D., Boynton, W.V., Carswell, A., Catling, D.C., Clark, B.C., Duck, T., DeJong, E., Fisher, D., Goetz, W., Gunnlaugsson, Haraldur Pall, Hecht, M.H., Hipkin, V., Hoffman, J., Hviid, S.F., Keller, H.U., Kounaves, S.P., Lange, C.F., Lemmon, M.T., Madsen, M.B., Markiewicz, W.J., Marshall, J., McKay, C.P., Mellon, M.T., Ming, D.W., Morris, R.W., Pike, W.T., Renno, N., Staufer, U., Stoker, C., Taylor, P., Whiteway, J.A., and Zent, A.P.

Published
2009

61. Introduction to special section on the Phoenix Mission: Landing Site Characterization Experiments, Mission Overviews, and Expected Science

Author

Smith, P.H., Tamppari, L., Arvidson, R.E., Bass, D., Blaney, D., Boynton, W., Carswell, A., Catling, D., Clark, B., Duck, T., DeJong, E., Fisher, D., Goetz, W., Gunnlaugsson, Haraldur Pall, Hecht, M., Hipkin, V., Hoffman, J., Hviid, S., Keller, H., Kounaves, S., Lange, C.F., Lemmon, M., Madsen, M., Malin, M., Markiewicz, W., Marshall, J., McKay, C., Mellon, M., Michelangeli, D., Ming, D., Morris, R., Renno, N., Pike, W.T., Staufer, U., Stoker, C., Taylor, P., Whiteway, J., Young, S., and Zent, A.

Published
2008

64. The eggshell features and clutch viability of the broad-snouted caiman (Caiman latirostris) are associated with the egg burden of organochlorine compounds

Author

Stoker, C., primary, Zayas, M.A., additional, Ferreira, M.A., additional, Durando, M., additional, Galoppo, G.H., additional, Rodríguez, H.A., additional, Repetti, M.R., additional, Beldoménico, H.R., additional, Caldini, E.G., additional, Luque, E.H., additional, and Muñoz-de-Toro, M., additional

Published
2013
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65. Reaching 1 m Deep on Mars: The Icebreaker Drill

Author

Zacny, K., primary, Paulsen, G., additional, McKay, C.P., additional, Glass, B., additional, Davé, A., additional, Davila, A.F., additional, Marinova, M., additional, Mellerowicz, B., additional, Heldmann, J., additional, Stoker, C., additional, Cabrol, N., additional, Hedlund, M., additional, and Craft, J., additional

Published
2013
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66. Astrobiology and habitability studies in preparation for future Mars missions: Trends from investigating minerals, organics and biota

Author

Ehrenfreund, P. (author), Röling, W.F.M. (author), Thiel, C.S. (author), Quinn, R. (author), Sephton, M.A. (author), Stoker, C. (author), Kotler, J.M. (author), Direito, S.O.L. (author), Martins, Z. (author), Orzechowska, G.E. (author), Kidd, R.D. (author), Van Sluis, C.A. (author), Foing, B.H. (author), Ehrenfreund, P. (author), Röling, W.F.M. (author), Thiel, C.S. (author), Quinn, R. (author), Sephton, M.A. (author), Stoker, C. (author), Kotler, J.M. (author), Direito, S.O.L. (author), Martins, Z. (author), Orzechowska, G.E. (author), Kidd, R.D. (author), Van Sluis, C.A. (author), and Foing, B.H. (author)

Abstract

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

Published
2011
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67. Deep subsurface sulfate reduction and methanogenesis in the Iberian Pyrite Belt revealed through geochemistry and molecular biomarkers

Author

Puente-Sánchez, F., primary, Moreno-Paz, M., additional, Rivas, L. A., additional, Cruz-Gil, P., additional, García-Villadangos, M., additional, Gómez, M. J., additional, Postigo, M., additional, Garrido, P., additional, González-Toril, E., additional, Briones, C., additional, Fernández-Remolar, D., additional, Stoker, C., additional, Amils, R., additional, and Parro, V., additional

Published
2013
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69. Astrobiology and habitability studies in preparation for future Mars missions: trends from investigating minerals, organics and biota

Author

Ehrenfreund, P., primary, Röling, W.F.M., additional, Thiel, C.S., additional, Quinn, R., additional, Sephton, M.A., additional, Stoker, C., additional, Kotler, J.M., additional, Direito, S.O.L., additional, Martins, Z., additional, Orzechowska, G.E., additional, Kidd, R.D., additional, van Sluis, C.A, additional, and Foing, B.H., additional

Published
2011
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70. H 2 O at the Phoenix Landing Site

Author

Smith, P. H., primary, Tamppari, L. K., additional, Arvidson, R. E., additional, Bass, D., additional, Blaney, D., additional, Boynton, W. V., additional, Carswell, A., additional, Catling, D. C., additional, Clark, B. C., additional, Duck, T., additional, DeJong, E., additional, Fisher, D., additional, Goetz, W., additional, Gunnlaugsson, H. P., additional, Hecht, M. H., additional, Hipkin, V., additional, Hoffman, J., additional, Hviid, S. F., additional, Keller, H. U., additional, Kounaves, S. P., additional, Lange, C. F., additional, Lemmon, M. T., additional, Madsen, M. B., additional, Markiewicz, W. J., additional, Marshall, J., additional, McKay, C. P., additional, Mellon, M. T., additional, Ming, D. W., additional, Morris, R. V., additional, Pike, W. T., additional, Renno, N., additional, Staufer, U., additional, Stoker, C., additional, Taylor, P., additional, Whiteway, J. A., additional, and Zent, A. P., additional

Published
2009
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71. Experimental simulations of oxidizing conditions and organic decomposition on the surface of Mars

Author

Stoker, C. R, Mancinelli, Rocco L, and Mckay, Christopher P

Subjects
Inorganic And Physical Chemistry
Abstract

One important scientific objective of a Mars Rover Sample Return mission would be to look for traces of living and extinct life on Mars. An instrument to search for organic carbon may be the simplest instrument that could screen samples which are interesting from a biological point of view. An experimental program is described which would help to understand the nature of the oxidizing soil on Mars and the mechanism responsible for organic degradation on the Martian surface. This is approached by lab simulations of the actual conditions that occur on Mars, particularly the oxidant production by atmospheric photochemistry, and the combined effects of UV light and oxidants in decomposing organic compounds. The results will be used to formulate models of the photochemistry of the atmospheric, the atmosphere-soil interaction, and the diffusion of reactive compounds into the soils. This information will provide insights and constraints on the design of a sampling strategy to search for organic compounds on Mars.

Published
1988

72. Moisture driven convection on Jupiter: A mechanism to produce the equatorial plumes

Author

Stoker, C

Subjects
Lunar And Planetary Exploration
Abstract

Possible roles are explored for moist convection in the production of bright plume features in the Jupiter atmosphere. The features have been observed at least since 1881. A one-dimensional model is developed for a Jovian cloud and the conditions necessary for convection to occur on Jupiter are defined. The model is used to predict the vertical velocity and maximum altitude of moist clouds that are convected over a vertical extent of 100, 10 and 1 km. Convection within the ammonia layer would not produce sufficient buoyancy to sublime from the rising air parcel. Water rising from the 5 bar to 1 bar level could carry enough ammonia to the cooler region to form plume anvils in the stable layer above 700 mbar. If unpolluted during the convection, the water could be the source of high altitude haze above the entire equatorial zone.

Published
1986

73. Moist convection - A mechanism for producing the vertical structure of the Jovian equatorial plumes

Author

Stoker, C. R

Subjects
Lunar And Planetary Exploration
Abstract

Possible roles are explored for moist convection in the production of bright plume features in the Jupiter atmosphere. The features have been observed at least since 1881. A one-dimensional model is developed for a Jovian cloud and the conditions necessary for convection to occur on Jupiter are defined. The model is used to predict the vertical velocity and maximum altitude of moist clouds that are convected over a vertical extent of 100, 10 and 1 km. Convection within the ammonia layer would not produce sufficient buoyancy to sublime from the rising air parcel. Water rising from the 5 bar to 1 bar level could carry enough ammonia to the cooler region to form plume anvils in the stable layer above 700 mbar. If unpolluted during the convection, the water could be the source of high altitude haze above the entire equatorial zone.

Published
1986
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74. The case for Mars: Concept development for a Mars research station

Author

Welch, S. M and Stoker, C. R

Subjects
Lunar And Planetary Exploration
Abstract

A program to establish a permanent scientific research base on Mars is described. A Mars base as the much needed long-term focus for the space program is presented. A permanent base was chosen rather than the more conventional concept of a series of individual missions to different sites because the permanent base offers much greater scientific return plus greater crew safety and the potential for eventual growth into a settlement. The Mars base will strive for self-sufficiency and autonomy from Earth. Martian resources will be used to provide life support materials and consumables. The Martian atmosphere will provide a convenient source of volatiles: CO2, N2, and water. Rocket propellant (for returning vehicles), fuels, breathable air, and fertilizers will be manufactured from Mars air. Food will be grown on Mars using Martian materials as plant nutrients. A permanent human presence will be maintained on Mars beginning with the first manned landing via a strategy of crew overlap. This permanent presence will ensure safety and reliability of systems through continuous tending, maintenance, and expansion of the base's equipment and systems. A permanent base will allow the development of a substantial facility on Mars for the same cost (in terms of Earth departure mass) as a series of temporary camps. A base equipped with surface rovers, airplanes, and the ability to manufacture consumables and return propellant will allow far more extensive planetary exploration over a given period of years than would approaches featuring a series of short exploration missions such as the Apollo Moon program.

Published
1986

75. Vertical cloud structure of Jupiter's equatorial plumes

Author

Stoker, C. R and Hord, C

Subjects
Lunar And Planetary Exploration
Abstract

Multiple-scattering radiative transfer calculations were used to deduce the vertical cloud structure (VCS) of Jupiter's equatorial region. The VCS model of the equatorial plumes is obtained through an analysis of Voyager images of the 6190-A methane band and the 6000-A continuum, and ground-based 8900-A methane band images. The VCS of the equatorial plumes is found to be consistent with the hypothesis that the plumes are caused by upwelling at the ammonia condensation level produced by buoyancy due to latent heat release from the condensation of water clouds nearly three scale heights below the plumes.

Published
1985
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76. Space Station gas-grain simulation facility - Application to exobiology

Author

Mckay, C. P, Stoker, C. R, Morris, J, Conley, G, and Schwartz, D

Subjects
Space Biology
Abstract

The technical issues involved in performing experiments on the behavior and properties of aerosols in a microgravity environment provided by the Space Station are reviewed. The displacement of a particle resulting from g-jitter for ballistic, Knudsen, and Stokes flow regimes is examined in detail, and the radiation, acoustic, electrostatic, and electromagnetic mechanisms for the control of this motion are described. The simulation of organic haze production on Titan has been selected as an example experiment for detailed study. The purpose of this experiment was to simulate the photolysis of methane and the subsequent formation of the organic haze particles in the Titan upper atmosphere.

Published
1986
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77. Electronics systems test laboratory testing of shuttle communications systems

Author

Stoker, C. J and Bromley, L. K

Subjects
Communications And Radar
Abstract

Shuttle communications and tracking systems space to space and space to ground compatibility and performance evaluations are conducted in the NASA Johnson Space Center Electronics Systems Test Laboratory (ESTL). This evaluation is accomplished through systems verification/certification tests using orbiter communications hardware in conjunction with other shuttle communications and tracking external elements to evaluate end to end system compatibility and to verify/certify that overall system performance meets program requirements before manned flight usage. In this role, the ESTL serves as a multielement major ground test facility. The ESTL capability and program concept are discussed. The system test philosophy for the complex communications channels is described in terms of the major phases. Results of space to space and space to ground systems tests are presented. Several examples of the ESTL's unique capabilities to locate and help resolve potential problems are discussed in detail.

Published
1985

78. Introduction to special section on the Phoenix Mission: Landing Site Characterization Experiments, Mission Overviews, and Expected Science

Author

Smith, P. H., primary, Tamppari, L., additional, Arvidson, R. E., additional, Bass, D., additional, Blaney, D., additional, Boynton, W., additional, Carswell, A., additional, Catling, D., additional, Clark, B., additional, Duck, T., additional, DeJong, E., additional, Fisher, D., additional, Goetz, W., additional, Gunnlaugsson, P., additional, Hecht, M., additional, Hipkin, V., additional, Hoffman, J., additional, Hviid, S., additional, Keller, H., additional, Kounaves, S., additional, Lange, C. F., additional, Lemmon, M., additional, Madsen, M., additional, Malin, M., additional, Markiewicz, W., additional, Marshall, J., additional, McKay, C., additional, Mellon, M., additional, Michelangeli, D., additional, Ming, D., additional, Morris, R., additional, Renno, N., additional, Pike, W. T., additional, Staufer, U., additional, Stoker, C., additional, Taylor, P., additional, Whiteway, J., additional, Young, S., additional, and Zent, A., additional

Published
2008
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79. Drilling Systems for Extraterrestrial Subsurface Exploration

Author

Zacny, K., primary, Bar-Cohen, Y., additional, Brennan, M., additional, Briggs, G., additional, Cooper, G., additional, Davis, K., additional, Dolgin, B., additional, Glaser, D., additional, Glass, B., additional, Gorevan, S., additional, Guerrero, J., additional, McKay, C., additional, Paulsen, G., additional, Stanley, S., additional, and Stoker, C., additional

Published
2008
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80. Space shuttle data handling and communications considerations.

Author

Stoker, C. J and Minor, R. G

Subjects
Communications
Abstract

Operational and development flight instrumentation, data handling subsystems and communication requirements of the space shuttle orbiter are discussed. Emphasis is made on data gathering methods, crew display data, computer processing, recording, and telemetry by means of a digital data bus. Also considered are overall communication conceptual system aspects and design features allowing a proper specification of telemetry encoders and instrumentation recorders. An adaptive bit rate concept is proposed to handle the telemetry bit rates which vary with the amount of operational and experimental data to be transmitted. A split-phase encoding technique is proposed for telemetry to cope with the excessive bit jitter and low bit transition density which may affect television performance.

Published
1971

82. Microbial metabolism of tholin

Author

Stoker, C. R., Boston, P. J., Mancinelli, R. L., Segal, W., Khare, B. N., and Sagan, C.

Abstract

n/a

Published
1990

86. Overview of the Mars Pathfinder Mission: Launch Through Landing, Surface Operations, Data Sets, and Science Results

Author

Golombek, M.P., Anderson, R.C., Barnes, Jacob Roland, Bell III, J.F., Bridges, N.T., Britt, D.T., Brückner, J., Cook, R.A., Crisp, D., Crisp, J., Economou, T., Folkner, W.M., Greeley, R., Haberle, R.M., Hargraves, R.B., Harris, J.A., Haldemann, A.F.C., Hviid, S.F., Jaumann, R., Johnson, J.R., Herkenhoff, K.E., Kallemeyn, P. H.ry W., Keller, H.U., Kirk, R.L., Knudsen, Jens Martin, Larsen, S., Lemmon, M., Madsen, M.B., Magelhäes, J.A., Manning, R.M., Maki, J.N., Malin, M.C., Matijevic, J., McSween Jr., H.Y., Moore, H.J., Murchie, S.L., Murphy, J.R., Parker, T.J., Rieder, R., Schofield, J.T., Seiff, A., Singer, R.B., Smith, P.H., Soderblom, L.A., Spencer, D.A., Stoker, C., Sullivan, R.P., Thomas, N., Thurman, S.W., Tomasko, M.G., Vaughan, R.M., Wänke, H., Ward, W., Wilson, G., Golombek, M.P., Anderson, R.C., Barnes, Jacob Roland, Bell III, J.F., Bridges, N.T., Britt, D.T., Brückner, J., Cook, R.A., Crisp, D., Crisp, J., Economou, T., Folkner, W.M., Greeley, R., Haberle, R.M., Hargraves, R.B., Harris, J.A., Haldemann, A.F.C., Hviid, S.F., Jaumann, R., Johnson, J.R., Herkenhoff, K.E., Kallemeyn, P. H.ry W., Keller, H.U., Kirk, R.L., Knudsen, Jens Martin, Larsen, S., Lemmon, M., Madsen, M.B., Magelhäes, J.A., Manning, R.M., Maki, J.N., Malin, M.C., Matijevic, J., McSween Jr., H.Y., Moore, H.J., Murchie, S.L., Murphy, J.R., Parker, T.J., Rieder, R., Schofield, J.T., Seiff, A., Singer, R.B., Smith, P.H., Soderblom, L.A., Spencer, D.A., Stoker, C., Sullivan, R.P., Thomas, N., Thurman, S.W., Tomasko, M.G., Vaughan, R.M., Wänke, H., Ward, W., and Wilson, G.

Published
1998

89. Nomad Rover Field Experiment, Atacama Desert, Chile: 2. Identification of paleolife evidence using a robotic vehicle: Lessons and recommendations for a Mars sample return mission

Author

Cabrol, N. A., primary, Bettis, E. A., additional, Glenister, B., additional, Chong, G., additional, Herrera, C., additional, Jensen, A., additional, Pereira, M., additional, Stoker, C. R., additional, Grin, E. A., additional, Landheim, R., additional, Thomas, G., additional, Golden, J., additional, Saville, K., additional, Ludvigson, G., additional, and Witzke, B., additional

Published
2001
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90. The 1999 Marsokhod rover mission simulation at Silver Lake, California: Mission overview, data sets, and summary of results

Author

Stoker, C. R., primary, Cabrol, N. A., additional, Roush, T. R., additional, Moersch, J., additional, Aubele, J., additional, Barlow, N., additional, Bettis, E. A., additional, Bishop, J., additional, Chapman, M., additional, Clifford, S., additional, Cockell, C., additional, Crumpler, L., additional, Craddock, R., additional, De Hon, R., additional, Foster, T., additional, Gulick, V., additional, Grin, E., additional, Horton, K., additional, Hovde, G., additional, Johnson, J. R., additional, Lee, P. C., additional, Lemmon, M. T., additional, Marshall, J., additional, Newsom, H. E., additional, Ori, G. G., additional, Reagan, M., additional, Rice, J. W., additional, Ruff, S. W., additional, Schreiner, J., additional, Sims, M., additional, Smith, P. H., additional, Tanaka, K., additional, Thomas, H. J., additional, Thomas, G., additional, and Yingst, R. A., additional

Published
2001
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91. Nomad Rover Field Experiment, Atacama Desert, Chile: 1. Science results overview

Author

Cabrol, N. A., primary, Chong-Diaz, G., additional, Stoker, C. R., additional, Gulick, V. C., additional, Landheim, R., additional, Lee, P., additional, Roush, T. L., additional, Zent, A. P., additional, Lameli, C. Herrera, additional, Iglesia, A. Jensen, additional, Arrerondo, M. Pereira, additional, Dohm, J. M., additional, Keaten, R., additional, Wettergreen, D., additional, Sims, M. H., additional, Schwher, K., additional, Bualat, M. G., additional, Thomas, H. J., additional, Zbinden, E., additional, Christian, D., additional, Pedersen, L., additional, Bettis, A., additional, Thomas, G., additional, and Witzke, B., additional

Published
2001
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92. Deep subsurface sulfate reduction and methanogenesis in the Iberian Pyrite Belt revealed through geochemistry and molecular biomarkers.

Author

Puente‐Sánchez, F., Moreno‐Paz, M., Rivas, L. A., Cruz‐Gil, P., García‐Villadangos, M., Gómez, M. J., Postigo, M., Garrido, P., González‐Toril, E., Briones, C., Fernández‐Remolar, D., Stoker, C., Amils, R., and Parro, V.

Subjects
PYRITES, SULFATE-reducing bacteria, BIOMARKERS, GEOCHEMISTRY, OXIDATION, METHANE
Abstract

The Iberian Pyrite Belt ( IPB, southwest of Spain), the largest known massive sulfide deposit, fuels a rich chemolithotrophic microbial community in the Río Tinto area. However, the geomicrobiology of its deep subsurface is still unexplored. Herein, we report on the geochemistry and prokaryotic diversity in the subsurface (down to a depth of 166 m) of the Iberian Pyritic belt using an array of geochemical and complementary molecular ecology techniques. Using an antibody microarray, we detected polymeric biomarkers (lipoteichoic acids and peptidoglycan) from Gram-positive bacteria throughout the borehole. DNA microarray hybridization confirmed the presence of members of methane oxidizers, sulfate-reducers, metal and sulfur oxidizers, and methanogenic Euryarchaeota. DNA sequences from denitrifying and hydrogenotrophic bacteria were also identified. FISH hybridization revealed live bacterial clusters associated with microniches on mineral surfaces. These results, together with measures of the geochemical parameters in the borehole, allowed us to create a preliminary scheme of the biogeochemical processes that could be operating in the deep subsurface of the Iberian Pyrite Belt, including microbial metabolisms such as sulfate reduction, methanogenesis and anaerobic methane oxidation. [ABSTRACT FROM AUTHOR]

Published
2014
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93. Overview of the Mars Pathfinder Mission: Launch through landing, surface operations, data sets, and science results

Author

Golombek, M. P., primary, Anderson, R. C., additional, Barnes, J. R., additional, Bell, J. F., additional, Bridges, N. T., additional, Britt, D. T., additional, Brückner, J., additional, Cook, R. A., additional, Crisp, D., additional, Crisp, J. A., additional, Economou, T., additional, Folkner, W. M., additional, Greeley, R., additional, Haberle, R. M., additional, Hargraves, R. B., additional, Harris, J. A., additional, Haldemann, A. F. C., additional, Herkenhoff, K. E., additional, Hviid, S. F., additional, Jaumann, R., additional, Johnson, J. R., additional, Kallemeyn, P. H., additional, Keller, H. U., additional, Kirk, R. L., additional, Knudsen, J. M., additional, Larsen, S., additional, Lemmon, M. T., additional, Madsen, M. B., additional, Magalhães, J. A., additional, Maki, J. N., additional, Malin, M. C., additional, Manning, R. M., additional, Matijevic, J., additional, McSween, H. Y., additional, Moore, H. J., additional, Murchie, S. L., additional, Murphy, J. R., additional, Parker, T. J., additional, Rieder, R., additional, Rivellini, T. P., additional, Schofield, J. T., additional, Seiff, A., additional, Singer, R. B., additional, Smith, P. H., additional, Soderblom, L. A., additional, Spencer, D. A., additional, Stoker, C. R., additional, Sullivan, R., additional, Thomas, N., additional, Thurman, S. W., additional, Tomasko, M. G., additional, Vaughan, R. M., additional, Wänke, H., additional, Ward, A. W., additional, and Wilson, G. R., additional

Published
1999
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95. Field astrobiology research in Moon–Mars analogue environments: instruments and methods.

Author

Foing, B.H., Stoker, C., Zavaleta, J., Ehrenfreund, P., Thiel, C., Sarrazin, P., Blake, D., Page, J., Pletser, V., Hendrikse, J., Direito, S., Kotler, J.M., Martins, Z., Orzechowska, G., Gross, C., Wendt, L., Clarke, J., Borst, A.M., Peters, S.T.M., and Wilhelm, M.-B.

Subjects
*SPACE biology, *REMOTE sensing, *FIELD research, *MICROBIAL mats, *GEOMORPHOLOGY, *MARTIAN geology, *MARTIAN exploration, *MARS (Planet)
Abstract

We describe the field demonstration of astrobiology instruments and research methods conducted in and from the Mars Desert Research Station (MDRS) in Utah during the EuroGeoMars campaign 2009 coordinated by ILEWG, ESA/ESTEC and NASA Ames, with the contribution of academic partners. We discuss the entire experimental approach from determining the geological context using remote sensing, in situ measurements, sorties with sample collection and characterization, analysis in the field laboratory, to the post sample analysis using advanced laboratory facilities.We present the rationale for terrestrial field campaigns to strengthen astrobiology research and the link between in situ and orbital remote sensing data. These campaigns are supporting the preparation for future missions such as Mars Science Laboratory, ExoMars or Mars Sample Return. We describe the EuroGeoMars 2009 campaign conducted by MDRS crew 76 and 77, focused on the investigation of surface processes in their geological context. Special emphasis was placed on sample collection and pre-screening using in-situ portable instruments. Science investigations included geological and geochemical measurements as well as detection and diagnostic of water, oxidants, organic matter, minerals, volatiles and biota.EuroGeoMars 2009 was an example of a Moon–Mars field research campaign dedicated to the demonstration of astrobiology instruments and a specific methodology of comprehensive measurements from selected sampling sites. We discuss in sequence: the campaign objectives and trade-off based on science, technical or operational constraints. This includes remote sensing data and maps, and geological context; the monitoring of environmental parameters; the geophysical context and mineralogy studies; geology and geomorphology investigations; geochemistry characterization and subsurface studies.We describe sample handling (extraction and collection) methods, and the sample analysis of soils and rocks performed in the MDRS laboratory using close inspection, initial petrological characterization, microscopy, Visible-NIR spectrometry, Raman spectrometry, X-ray diffraction/X-ray fluorescence spectrometry, soil analysis, electrochemical and biological measurements.The results from post-mission analysis of returned samples using advanced facilities in collaborator institutes are described in companion papers in this issue. We present examples of in-situ analysis, and describe an example investigation on the exploration and analysis of endolithic microbial mats (from reconnaissance, in-situ imaging, sampling, local analysis to post-mission sample analysis). [ABSTRACT FROM AUTHOR]

Published
2011
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99. EUROMOONMARS HIGHLIGHTS FROM TERRESTRIAL ANALOGUES.

Author

Foing, B., Stoker, C., Rogers, H., Musilova, M., Weert, A., Mulder, S., Kerber, S., Castro, A., Pouwels, C., Rajkakati, P. Das, Heemskerk, M., Heemskerk, R., Sirikan, N., Boross, H., Kolodziejczyk, A., Perrier, I. R., Laffont, M., Landolina, R., Spilkin, A., and Tavernier, A.

Subjects
BASALT
Published
2021

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