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4. Analytical techniques for retrieval of atmospheric composition with the quadrupole mass spectrometer of the Sample Analysis at Mars instrument suite on Mars Science Laboratory

Author

B. Franz, Heather, G. Trainer, Melissa, H. Wong, Michael, L.K. Manning, Heidi, C. Stern, Jennifer, R. Mahaffy, Paul, K. Atreya, Sushil, Benna, Mehdi, G. Conrad, Pamela, N. Harpold, Dan, A. Leshin, Laurie, A. Malespin, Charles, P. McKay, Christopher, Thomas Nolan, J., and Raaen, Eric

Published
2014
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7. Comet 81p/Wild 2 under a Microscope

Author

Brownlee, Don, Tsou, Peter, Aléon, Jérôme, Alexander, Conel M. O'D., Araki, Tohru, Bajt, Sasa, Baratta, Giuseppe A., Bastien, Ron, Bland, Phil, Bleuet, Pierre, Borg, Janet, Bradley, John P., Brearley, Adrian, Brenker, F., Brennan, Sean, Bridges, John C., Browning, Nigel D., Brucato, John R., Bullock, E., Burchell, Mark J., Busemann, Henner, Butterworth, Anna, Chaussidon, Marc, Cheuvront, Allan, Chi, Miaofang, Cintala, Mark J., Clark, B. C., Clemett, Simon J., Cody, George, Colangeli, Luigi, Cooper, George, Cordier, Patrick, Daghlian, C., Dai, Zurong, D'Hendecourt, Louis, Djouadi, Zahia, Dominguez, Gerardo, Duxbury, Tom, Dworkin, Jason P., Ebel, Denton S., Economou, Thanasis E., Fakra, Sirine, Fairey, Sam A. J., Fallon, Stewart, Ferrini, Gianluca, Ferroir, T., Fleckenstein, Holger, Floss, Christine, Flynn, George, Franchi, Ian A., Fries, Marc, Gainsforth, Z., Gallien, J.-P., Genge, Matt, Gilles, Mary K., Gillet, Philipe, Gilmour, Jamie, Glavin, Daniel P., Gounelle, Matthieu, Grady, Monica M., Graham, Giles A., Grant, P. G., Green, Simon F., Grossemy, Faustine, Grossman, Lawrence, Grossman, Jeffrey N., Guan, Yunbin, Hagiya, Kenji, Harvey, Ralph, Heck, Philipp, Herzog, Gregory F., Hoppe, Peter, Hörz, Friedrich, Huth, Joachim, Hutcheon, Ian D., Ignatyev, Konstantin, Ishii, Hope, Ito, Motoo, Jacob, Damien, Jacobsen, Chris, Jacobsen, Stein, Jones, Steven, Joswiak, David, Jurewicz, Amy, Kearsley, Anton T., Keller, Lindsay P., Khodja, H., Kilcoyne, A. L. David, Kissel, Jochen, Krot, Alexander, Langenhorst, Falko, Lanzirotti, Antonio, Le, Loan, Leshin, Laurie A., Leitner, J., Lemelle, L., Leroux, Hugues, Liu, Ming-Chang, Leuning, K., Lyon, Ian, MacPherson, Glen, Marcus, Matthew A., Marhas, Kuljeet, Marty, Bernard, Matrajt, Graciela, McKeegan, Kevin, Meibom, Anders, Mennella, Vito, Messenger, Keiko, Messenger, Scott, Mikouchi, Takeshi, Mostefaoui, Smail, Nakamura, Tomoki, Nakano, T., Newville, M., Nittler, Larry R., Ohnishi, Ichiro, Ohsumi, Kazumasa, Okudaira, Kyoko, Papanastassiou, Dimitri A., Palma, Russ, Palumbo, Maria E., Pepin, Robert O., Perkins, David, Perronnet, Murielle, Pianetta, P., Rao, William, Rietmeijer, Frans J. M., Robert, François, Rost, D., Rotundi, Alessandra, Ryan, Robert, Sandford, Scott A., Schwandt, Craig S., See, Thomas H., Schlutter, Dennis, Sheffield-Parker, J., Simionovici, Alexandre, Simon, Steven, Sitnitsky, I., Snead, Christopher J., Spencer, Maegan K., Stadermann, Frank J., Steele, Andrew, Stephan, Thomas, Stroud, Rhonda, Susini, Jean, Sutton, S. R., Suzuki, Y., Taheri, Mitra, Taylor, Susan, Teslich, Nick, Tomeoka, Kazu, Tomioka, Naotaka, Toppani, Alice, Trigo-Rodríguez, Josep M., Troadec, David, Tsuchiyama, Akira, Tuzzolino, Anthony J., Tyliszczak, Tolek, Uesugi, K., Velbel, Michael, Vellenga, Joe, Vicenzi, E., Vincze, L., Warren, Jack, Weber, Iris, Weisberg, Mike, Westphal, Andrew J., Wirick, Sue, Wooden, Diane, Wopenka, Brigitte, Wozniakiewicz, Penelope, Wright, Ian, Yabuta, Hikaru, Yano, Hajime, Young, Edward D., Zare, Richard N., Zega, Thomas, Ziegler, Karen, Zimmerman, Laurent, Zinner, Ernst, and Zolensky, Michael

Published
2006
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8. Isotopic Compositions of Cometary Matter Returned by Stardust

Author

McKeegan, Kevin D., Aléon, Jerome, Bradley, John, Brownlee, Donald, Busemann, Henner, Butterworth, Anna, Chaussidon, Marc, Fallon, Stewart, Floss, Christine, Gilmour, Jamie, Gounelle, Matthieu, Graham, Giles, Guan, Yunbin, Heck, Philipp R., Hoppe, Peter, Hutcheon, Ian D., Huth, Joachim, Ishii, Hope, Ito, Motoo, Jacobsen, Stein B., Kearsley, Anton, Leshin, Laurie A., Liu, Ming-Chang, Lyon, Ian, Marhas, Kuljeet, Marty, Bernard, Matrajt, Graciela, Meibom, Anders, Messenger, Scott, Mostefaoui, Smail, Mukhopadhyay, Sujoy, Nakamura-Messenger, Keiko, Nittler, Larry, Palma, Russ, Pepin, Robert O., Papanastassiou, Dimitri A., Robert, François, Schlutter, Dennis, Snead, Christopher J., Stadermann, Frank J., Stroud, Rhonda, Tsou, Peter, Westphal, Andrew, Young, Edward D., Ziegler, Karen, Zimmermann, Laurent, and Zinner, Ernst

Published
2006
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15. Evidence for Perchlorates and the Origin of Chlorinated Hydrocarbons Detected by SAM at the Rocknest Aeolian Deposit in Gale Crater

Author

Glavin, Daniel P, Freissinet, Caroline, Miller, Kristen E, Eigenbrode, Jennifer L, Brunner, Anna E, Buch, Arnaud, Sutter, Brad, Archer, P. Douglas, Jr, Atreya, Sushil K, Brinckerhoff, William B, Cabane, Michel, Coll, Patrice, Conrad, Pamela G, Coscia, David, Dworkin, Jason P, Franz, Heather B, Grotzinger, John P, Leshin, Laurie A, Martin, Mildred G, McKay, Christopher, Ming, Douglas W, Navarro-Gonzalez, Rafael, Pavlov, Alexander, Steele, Andrew, Summons, Roger E, Szopa, Cyril, Teinturier, Samuel, and Mahaffy, Paul R

Subjects
Lunar And Planetary Science And Exploration
Abstract

A single scoop of the Rocknest aeolian deposit was sieved (less than 150 micrometers), and four separate sample portions, each with a mass of approximately 50 mg, were delivered to individual cups inside the Sample Analysis at Mars (SAM) instrument by the Mars Science Laboratory rover's sample acquisition system. The samples were analyzed separately by the SAM pyrolysis evolved gas and gas chromatograph mass spectrometer analysis modes. Several chlorinated hydrocarbons including chloromethane, dichloromethane, trichloromethane, a chloromethylpropene, and chlorobenzene were identified by SAM above background levels with abundances of approximately 0.01 to 2.3 nmol. The evolution of the chloromethanes observed during pyrolysis is coincident with the increase in O2 released from the Rocknest sample and the decomposition of a product of N-methyl-N-(tert-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA), a chemical whose vapors were released from a derivatization cup inside SAM. The best candidate for the oxychlorine compounds in Rocknest is a hydrated calcium perchlorate (Ca(ClO4)2·nH2O), based on the temperature release of O2 that correlates with the release of the chlorinated hydrocarbons measured by SAM, although other chlorine-bearing phases are being considered. Laboratory analog experiments suggest that the reaction of Martian chlorine from perchlorate decomposition with terrestrial organic carbon from MTBSTFA during pyrolysis can explain the presence of three chloromethanes and a chloromethylpropene detected by SAM. Chlorobenzene may be attributed to reactions of Martian chlorine released during pyrolysis with terrestrial benzene or toluene derived from 2,6-diphenylphenylene oxide (Tenax) on the SAM hydrocarbon trap. At this time we do not have definitive evidence to support a nonterrestrial carbon source for these chlorinated hydrocarbons, nor do we exclude the possibility that future SAM analyses will reveal the presence of organic compounds native to the Martian regolith.

Published
2013
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24. Chemistry of fracture-filling raised ridges in Yellowknife Bay, Gale Crater: Window into past aqueous activity and habitability on Mars.

Author

Léveillé, Richard J., Bridges, John, Wiens, Roger C., Mangold, Nicolas, Cousin, Agnes, Lanza, Nina, Forni, Olivier, Ollila, Ann, Grotzinger, John, Clegg, Samuel, Siebach, Kirsten, Berger, Gilles, Clark, Ben, Fabre, Cécile, Anderson, Ryan, Gasnault, Olivier, Blaney, Diana, Deflores, Lauren, Leshin, Laurie, and Maurice, Sylvestre

Published
2014
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25. Abundances and implications of volatile-bearing species from evolved gas analysis of the Rocknest aeolian deposit, Gale Crater, Mars.

Author

Archer, Paul Douglas, Franz, Heather B., Sutter, Brad, Arevalo, Ricardo D., Coll, Patrice, Eigenbrode, Jennifer L., Glavin, Daniel P., Jones, John J., Leshin, Laurie A., Mahaffy, Paul R., McAdam, Amy C., McKay, Christopher P., Ming, Douglas W., Morris, Richard V., Navarro-González, Rafael, Niles, Paul B., Pavlov, Alex, Squyres, Steven W., Stern, Jennifer C., and Steele, Andrew

Published
2014
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27. Assessment of shock effects on amphibole water contents and hydrogen isotope compositions: 2. Kaersutitic amphibole experiments

Author

Minitti, Michelle E., Leshin, Laurie A., Dyar, M. Darby, Ahrens, Thomas J., Guan, Yunbin, and Luo, Sheng-Nian

Subjects
*PLANETS, *AMPHIBOLES, *HYDROGEN isotopes, *SOLAR system
Abstract

Abstract: To constrain the influence of impact shock on water and hydrogen isotope signatures of Martian meteorite kaersutites, we conducted shock recovery experiments on three terrestrial kaersutite crystals. Homogeneous impact shock to 32 GPa, commensurate with shock levels experienced by Martian meteorite kaersutites, led to increases in kaersutite water contents (ΔH2O=0.25–0.89 wt.%), decreases in Fe3+/ΣFe (4–20%), and enrichments in hydrogen isotope composition (ΔD=+66 to +87‰) relative to pre-shock values. The latter values represent the largest shock-induced hydrogen isotope fractionations measured to date. These observations are explained most completely by a two-step shock process. First, shock-induced devolatilization led to hydrogen isotope enrichment through preferential loss of H relative to D. Second, reaction of the kaersutite with the ambient atmosphere led to increased water contents and reduced Fe. Fe reduction and water addition via the reaction Fe2+ +OH− ↔Fe3+ +O2− +½H2 explain the Fe3+/ΣFe data and some of the water data. Further water addition mechanisms (irreversible adsorption, shock implantation) are necessary to fully explain the increased water contents. Addition of water from the terrestrial atmosphere, which is isotopically light relative to the experimental kaersutite compositions, means the measured hydrogen isotope enrichments are likely minima. The measured (minimum) levels of hydrogen isotope enrichment are relevant to the hydrogen isotope variability within and among Martian kaersutites, but are minor relative to their absolute δD values. Alternatively, addition of water from the enriched Martian atmosphere could explain both Martian kaersutite hydrogen isotope variability and absolute δD values. However, the low Martian kaersutite water contents leave little room for significant water addition. The importance of the ambient atmosphere to the outcome of the shock experiments makes it difficult to translate our results to Mars given the unknown influence of its more tenuous atmosphere on the processes observed in the experiments. Our results suggest that shock is a feasible mechanism for influencing Martian kaersutite water contents and hydrogen isotope compositions but that its complex signature precludes precise determination of that influence. [Copyright &y& Elsevier]

Published
2008
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29. Intercalibration of FTIR and SIMS for hydrogen measurements in glasses and nominally anhydrous minerals.

Author

Aubaud, Cyril, Withers, Anthony C., Hirschmann, Marc M., Yunbin Guan, Leshin, Laurie A., Mackwell, Stephen J., and Bell, David R.

Subjects
CALIBRATION, FOURIER transform infrared spectroscopy, SECONDARY ion mass spectrometry, HYDROGEN, GLASS, SPECTRUM analysis
Abstract

We present new Fourier Transform Infrared Spectroscopy (FTIR) and ion microprobe/secondary ion mass spectrometry (SIMS) analyses of ¹H in 61 natural and experimental geological samples. These samples include 8 basaltic glasses (0.17 to 7.65 wt% H2O), 11 rhyolitic glasses (0.143 to 6.20 wt% H2O), 17 olivines (∼0 to 910 wt. ppm H2O), 9 orthopyroxenes (∼0 to 263 wt. ppm H2O), 8 clinopyroxenes (∼0 to 490 wt. ppm H2O), and 8 garnets (∼0 to 189 wt. ppm H2O). By careful attention to vacuum quality, the use a Cs+ primary beam, and a resin-free mounting technique, we routinely achieve hydrogen backgrounds equivalent to less than 5 ppm by weight H2O in olivine. Compared to previous efforts, the new calibration extends to a wider range of H2O contents for the minerals and is more reliable owing to a larger number of standards and to characterization of anisotropic minerals by polarized FTIR on oriented crystals. When observed, discrepancies between FTIR and SIMS measurements are attributable to inclusions of hydrous minerals or fluid inclusions in the crystals. Inclusions more commonly interfere with FTIR analyses than with SIMS, owing to the much larger volume sampled by the former. Plots of H2O determined by FTIR vs. (¹H/30Si) x (SiO2), determined by SIMS and electron microprobe (EMP) yield linear arrays and for each phase appear to be insensitive to bulk composition. For example, basalt and rhyolite calibration slopes cannot be distinguished. On the other hand, calibration slopes of different phases vary by up to a factor of 4. This reflects either phase-specific behavior of ¹H/30Si secondary ion ratios excited by Cs+ ion beams or discrepancies between phase-specific FTIR absorption coeficient schemes. [ABSTRACT FROM AUTHOR]

Published
2007
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32. Short-lived chlorine-36 in a Ca- and Al-rich inclusion from the Ningqiang carbonaceous chondrite.

Author

Yangting Lin, Yunbin Guan, Leshin, Laurie A., Ziyuan Ouyang, and Daode Wang

Subjects
CHLORINE, CHONDRITES, CHONDRULES, SULFUR, ATOMS, CHRONOMETERS
Abstract

Excesses of sulfur-36 in sodalite, a chlorine-rich mineral, in a calcium- and aluminum-rich inclusion from the Ningqiang carbonaceous chondrite linearly correlate with chorine/sulfur ratios, providing direct evidence for the presence of short-lived chlorine-36 (with a half-life of 0.3 million years) in the early solar system. The best inferred (36C1/35Cl)0 ratios of the sodalite are ≈5 × 10-6. Different from other short-lived radionuclides, chlorine-36 was introduced into the inclusion by solid-gas reaction during secondary alteration. The alteration reaction probably took place at least 1.5 million years after the first formation of the inclusion, based on the correlated study of the 26A1-26Mg systems of the relict primary minerals and the alteration assemblages, from which we inferred an initial ratio of (36Cl/35C1)o ⩾ 1.6 × 10-4 at the time when calcium- and aluminum-rich inclusions formed. This discovery supports a supernova origin of short-lived nuclides [Cameron, A. G. W., Hoeflich, P., Myers, P. C. & Clayton, D. D. (1995) Astrophys. J. 447, L53; Wasserburg, G. J., Gallino, R. & Busso, M. (1998) Astrophys. J. 500, L189-L193], but presents a serious challenge for local irradiation models [Shu, F. H.., Shang, H., Glassgold, A. E. & Lee, T. (1997) Science 277, 1475-1479; Gounelle, M., Shu, F. H., Shang, H., Glass- gold, A. E., Rehm, K. E. & Lee, T. (2001) Astrophys. J. 548, 1051-1070]. Furthermore, the short-lived 36Cl may serve as a unique fine-scale chronometer for volatile-rock interaction in the early solar system because of its close association with aqueous and/or anhydrous alteration processes. [ABSTRACT FROM AUTHOR]

Published
2005
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34. Thermal and Evolved Gas Analyzer: Part of the Mars Volatile and Climate Surveyor integrated payload.

Author

Boynton, William V., Bailey, Samuel H., Hamara, David K., Williams, Michael S., Bode, Rolfe C., Fitzgibbon, Michael R., Ko, WenJeng, Ward, Michael G., Sridhar, K. R., Blanchard, Jeff A., Lorenz, Ralph D., May, Randy D., Paige, David A., Pathare, Asmin V., Kring, David A., Leshin, Laurie A., Ming, Douglas W., Zent, Aaron P., Golden, D. C., and Kerry, Kristopher E.

Published
2001
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43. Insights into the formation of Fe- and Mg-rich aqueous solutions on early Mars provided by the ALH 84001 carbonates

Author

Niles, Paul B., Zolotov, Mikhail Yu., and Leshin, Laurie A.

Subjects
*GEOLOGICAL formations, *SOLUTION (Chemistry), *IRON, *MAGNESIUM, *CARBONATES, *METEORITES, *WATER-rock interaction, *CHEMICAL equilibrium, *MARTIAN geology, *MARS (Planet)
Abstract

Abstract: The chemical and isotopic pattern of the zoned carbonate globules in the ALH 84001 meteorite reveals a unique aqueous environment on early Mars. If the evolution of the fluid composition was dictated primarily by carbonate precipitation, the zoning pattern of the carbonates can constrain the fluid to have had an Mg/Ca mole ratio>~5.3 and a Fe/Ca mole ratio>~1 prior to the formation of the carbonates. Chemical equilibrium modeling of water–rock interactions indicates that low temperatures and low pH favor the formation of an aqueous solution with elevated Mg and Fe concentrations. The modeling shows that a sufficiently Fe- and Mg-rich fluid could have formed through low-temperature (<100 °C) subsurface aqueous alteration of an ALH 84001-type rock at pH 5–7. This range of pH corresponds to an elevated CO2 fugacity (~0.1–1 bar). Formation of ALH 84001 carbonates could have been driven by degassing of CO2 and corresponding pH increase in near-surface environments during an upwelling of subsurface CO2-rich solutions. This scenario is consistent with the unaltered nature of the ALH 84001 rock and with chemical and isotopic composition of its carbonates. [Copyright &y& Elsevier]

Published
2009
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44. Existence of an [sup 16]O-Rich Gaseous Reservoir in the Solar Nebula.

Author

Krot, Alexander N., McKeegan, Kevin D., Leshin, Laurie A., MacPherson, Glenn J., and Scott, Edward R. D.

Subjects
*NEBULAE, *CHONDRULES
Abstract

Carbonaceous chondrite condensate olivine grains from two distinct petrographic settings, calcium-aluminum-rich inclusion (CAI) accretionary rims and amoeboid olivine aggregates (AOAs), are oxygen-16 ([sup 16]O) enriched at the level previously observed inside CAIs. This requires that the gas in the nebular region where these grains condensed was [sup 16]O-rich. This contrasts with an [sup 16]O-poor gas present during the formation of chondrules, suggesting that CAIs and AOAs formed in a spatially restricted region of the solar nebula containing [sup 16]O-rich gas. The [sup 16]O-rich gas composition may have resulted either from mass-independent isotopic chemistry or from evaporation of regions with enhanced dust/gas ratios, possibly in an X-wind environment near the young Sun. [ABSTRACT FROM AUTHOR]

Published
2002
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45. Isotope Ratios of H, C, and 0 in C02 and H20 of the Martian Atmosphere.

Author

Webster, Chris R., Mahaffy, Paul R., Flesch, Gregory J., Niles, Paul B., Jones, John H., Leshin, Laurie A., Atreya, Sushil K., Stern, Jennifer C., Christensen, Lance E., Owen, Tobias, Franz, Heather, Pepin, Robert O., and Steele, Andrew

Subjects
*MARTIAN atmosphere, *ISOTOPES, *STABLE isotopes, *CARBON dioxide, *TUNABLE lasers, *QUADRUPOLE ion trap mass spectrometry
Abstract

Stable isotope ratios of H, C, and 0 are powerful indicators of a wide variety of planetary geophysical processes, and for Mars they reveal the record of loss of its atmosphere and subsequent interactions with its surface such as carbonate formation. We report in situ measurements of the isotopic ratios of D/H and 180/160 in water and 13C/12C, 180/160,170/160, and 13C180/12C160 in carbon dioxide, made in the martian atmosphere at Gale Crater from the Curiosity rover using the Sample Analysis at Mars (SAM)'s tunable laser spectrometer (TLS). Comparison between our measurements in the modern atmosphere and those of martian meteorites such as ALH 84001 implies that the martian reservoirs of C02 and H20 were largely established ~4 billion years ago, but that atmospheric loss or surface interaction may be still ongoing. [ABSTRACT FROM AUTHOR]

Published
2013
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46. Preferential low-pH dissolution of pyroxene in plagioclase–pyroxene mixtures: Implications for martian surface materials

Author

McAdam, Amy C., Zolotov, Mikhail Yu., Sharp, Thomas G., and Leshin, Laurie A.

Subjects
*ASTRONOMICAL research, *PYROXENE, *MARS (Planet), *ATMOSPHERE
Abstract

Abstract: Acid weathering of plagioclase–pyroxene mixtures has been investigated with an open system kinetic dissolution model. The modeling reveals that elevated plagioclase/pyroxene ratios observed in some low-albedo martian regions and atmospheric dust could be partially caused by preferential dissolution of pyroxenes at pHs below ∼3–4. Surface materials with smaller grain sizes, affected by lower pH fluids, and/or exposed to longer durations of acid weathering would be enriched in plagioclase. If preferential dissolution is responsible for the observed mineral ratios, the dissolution process likely occurred on a large scale, such as weathering by acid atmospheric precipitates. If dissolution was continuous, modeled timeframes required to produce a high plagioclase/pyroxene ratio are short on geologic timescales; however, it is likely that acid weathering on Mars was episodic, possibly occurring over a longer period of time. [Copyright &y& Elsevier]

Published
2008
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