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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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9. The Sample Analysis at Mars Investigation and Instrument Suite

Author

Mahaffy, Paul R., Webster, Christopher R., Cabane, Michel, Conrad, Pamela G., Coll, Patrice, Atreya, Sushil K., Arvey, Robert, Barciniak, Michael, Benna, Mehdi, Bleacher, Lora, Brinckerhoff, William B., Eigenbrode, Jennifer L., Carignan, Daniel, Cascia, Mark, Chalmers, Robert A., Dworkin, Jason P., Errigo, Therese, Everson, Paula, Franz, Heather, Farley, Rodger, Feng, Steven, Frazier, Gregory, Freissinet, Caroline, Glavin, Daniel P., Harpold, Daniel N., Hawk, Douglas, Holmes, Vincent, Johnson, Christopher S., Jones, Andrea, Jordan, Patrick, Kellogg, James, Lewis, Jesse, Lyness, Eric, Malespin, Charles A., Martin, David K., Maurer, John, McAdam, Amy C., McLennan, Douglas, Nolan, Thomas J., Noriega, Marvin, Pavlov, Alexander A., Prats, Benito, Raaen, Eric, Sheinman, Oren, Sheppard, David, Smith, James, Stern, Jennifer C., Tan, Florence, Trainer, Melissa, Ming, Douglas W., Morris, Richard V., Jones, John, Gundersen, Cindy, Steele, Andrew, Wray, James, Botta, Oliver, Leshin, Laurie A., Owen, Tobias, Battel, Steve, Jakosky, Bruce M., Manning, Heidi, Squyres, Steven, Navarro-González, Rafael, McKay, Christopher P., Raulin, Francois, Sternberg, Robert, Buch, Arnaud, Sorensen, Paul, Kline-Schoder, Robert, Coscia, David, Szopa, Cyril, Teinturier, Samuel, Baffes, Curt, Feldman, Jason, Flesch, Greg, Forouhar, Siamak, Garcia, Ray, Keymeulen, Didier, Woodward, Steve, Block, Bruce P., Arnett, Ken, Miller, Ryan, Edmonson, Charles, Gorevan, Stephen, and Mumm, Erik

Published
2012
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11. 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
Mars (Planet) -- Analysis, Astronomy, Earth sciences
Abstract

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2008.01.008 Byline: Amy C. McAdam (a), Mikhail Yu. Zolotov (a), Thomas G. Sharp (a), Laurie A. Leshin (b) Keywords: Mars; surface; Mineralogy 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 [approximately equal to]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. Author Affiliation: (a) School of Earth and Space Exploration, Arizona State University, Box 871404, Tempe, AZ 85287-1404, USA (b) Sciences and Exploration Directorate, Code 600, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA Article History: Received 5 June 2007; Revised 29 December 2007

Published
2008

12. The Deuterium to Hydrogen Ratio in the Water that Formed the Yellowknife Bay Mudstones in Gale Crater

Author

Mahaffy, Paul R, Brunner, Anna E, Webster, Chris R, Atreya, Sushil K, Mcadam, Amy Catherine, Stern, Jennifer Claire, Leshin, Laurie Ann, Navarro-Gonzales, Rafael, Jones, J, and Kashyap, Srishti

Subjects
Lunar And Planetary Science And Exploration, Astrophysics
Abstract

A suite of isotope ratios of light elements in the present martian atmosphere (13C/12C, 15N/14N, 18O/16O, 38Ar/36Ar, and D/H) are all substantially enriched in the heavy element suggesting atmospheric loss to space over the past billions of years with preferential loss of the lighter isotope from each pair. In situ measurements from MSL's Sample Analysis at Mars (SAM) instrument [e.g. 1,2,3] have considerably refined previous measurements from the Viking mass spectrometers [e.g. 4], from remote spectroscopic observations [e.g. 5,6], and from martian meteorite studies [e.g. 7,8]. The persistence of habitable environments such as the ancient Yellowknife Bay lake recently revealed by measurements from the Curiosity rover [9] depends on the surface temperatures and the duration of an atmosphere thicker than that at present. Current and planned measurements from orbit with the Mars Express and MAVEN missions respectively intend to study the processes of atmospheric escape including solar wind interaction, sputtering, thermal escape, and dissociative recombination, and determine or refine the current rate of atmospheric loss caused by these and other mechanisms. The goal of these programs is to understand the physical processes sufficiently well so that robust extrapolations over the past billions of years can be made D/H is measured by both the Tunable Laser Spectrometer (TLS) and the Quadrupole Mass Spectrometer (QMS) of the SAM suite. to predict the atmospheric and surface conditions on early Mars. However, the study of the history of martian atmospheric evolution will be greatly facilitated if we are able to also directly measure the isotopic composition of volatiles captured in rocks that are representative of the ancient atmosphere. To date, D/H is one of the most promising candidates for this study since water is the most abundant volatile thermally released from the Yellowknife Bay phylosilicates discovered by the SAM and CheMin experiments of MSL and its

Published
2014

13. Intercalibration of FTIR and SIMS for hydrogen measurements in glasses and nominally anhydrous minerals

Author

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

Subjects
Fourier transform infrared spectroscopy -- Usage, Microprobe analysis -- Usage, Hydrogen -- Measurement, Minerals -- Chemical properties, Earth sciences
Abstract

We present new Fourier Transform Infrared Spectroscopy (FTIR) and ion microprobe/secondary ion mass spectrometry (SIMS) analyses of [sup.1]H in 61 natural and experimental geological samples. These samples include 8 basaltic glasses (0.17 to 7.65 wt% [H.sub.2]O), 11 rhyolitic glasses (0.143 to 6.20 wt% [H.sub.2]O), 17 olivines (~0 to 910 wt. ppm [H.sub.2]O), 9 orthopyroxenes (~0 to 263 wt. ppm [H.sub.2]O), 8 clinopyroxenes (~0 to 490 wt. ppm [H.sub.2]0), and 8 garnets (~0 to 189 wt. ppm [H.sub.2]O). By careful attention to vacuum quality, the use a [Cs.sup.+] primary beam, and a resin-free mounting technique, we routinely achieve hydrogen backgrounds equivalent to less than 5 ppm by weight [H.sub.2]O in olivine. Compared to previous efforts, the new calibration extends to a wider range of [H.sub.2]O 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 [H.sub.2]O determined by FTIR vs. ([sup.1]H/[sup.30]Si) x (Si[O.sub.2]), 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 [sup.1]H/[sup.30]Si secondary ion ratios excited by [Cs.sup.+] ion beams or discrepancies between phase-specific FTIR absorption coefficient schemes. Keywords: Spectroscopy, infrared, water, mantle, ion microprobe

Published
2007

15. The Sample Analysis at Mars Investigation and Instrument Suite

Author

Mahaffy, Paul R., primary, Webster, Christopher R., additional, Cabane, Michel, additional, Conrad, Pamela G., additional, Coll, Patrice, additional, Atreya, Sushil K., additional, Arvey, Robert, additional, Barciniak, Michael, additional, Benna, Mehdi, additional, Bleacher, Lora, additional, Brinckerhoff, William B., additional, Eigenbrode, Jennifer L., additional, Carignan, Daniel, additional, Cascia, Mark, additional, Chalmers, Robert A., additional, Dworkin, Jason P., additional, Errigo, Therese, additional, Everson, Paula, additional, Franz, Heather, additional, Farley, Rodger, additional, Feng, Steven, additional, Frazier, Gregory, additional, Freissinet, Caroline, additional, Glavin, Daniel P., additional, Harpold, Daniel N., additional, Hawk, Douglas, additional, Holmes, Vincent, additional, Johnson, Christopher S., additional, Jones, Andrea, additional, Jordan, Patrick, additional, Kellogg, James, additional, Lewis, Jesse, additional, Lyness, Eric, additional, Malespin, Charles A., additional, Martin, David K., additional, Maurer, John, additional, McAdam, Amy C., additional, McLennan, Douglas, additional, Nolan, Thomas J., additional, Noriega, Marvin, additional, Pavlov, Alexander A., additional, Prats, Benito, additional, Raaen, Eric, additional, Sheinman, Oren, additional, Sheppard, David, additional, Smith, James, additional, Stern, Jennifer C., additional, Tan, Florence, additional, Trainer, Melissa, additional, Ming, Douglas W., additional, Morris, Richard V., additional, Jones, John, additional, Gundersen, Cindy, additional, Steele, Andrew, additional, Wray, James, additional, Botta, Oliver, additional, Leshin, Laurie A., additional, Owen, Tobias, additional, Battel, Steve, additional, Jakosky, Bruce M., additional, Manning, Heidi, additional, Squyres, Steven, additional, Navarro-González, Rafael, additional, McKay, Christopher P., additional, Raulin, Francois, additional, Sternberg, Robert, additional, Buch, Arnaud, additional, Sorensen, Paul, additional, Kline-Schoder, Robert, additional, Coscia, David, additional, Szopa, Cyril, additional, Teinturier, Samuel, additional, Baffes, Curt, additional, Feldman, Jason, additional, Flesch, Greg, additional, Forouhar, Siamak, additional, Garcia, Ray, additional, Keymeulen, Didier, additional, Woodward, Steve, additional, Block, Bruce P., additional, Arnett, Ken, additional, Miller, Ryan, additional, Edmonson, Charles, additional, Gorevan, Stephen, additional, and Mumm, Erik, additional

Published
2012
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18. The origin of water on Mars

Author

Lunine, Jonathan I., Chambers, John, Morbidelli, Alessandro, and Leshin, Laurie A.

Subjects
Planet formation -- Models, Planetesimals, Astronomy, Earth sciences
Abstract

This paper considers the origin of water on Mars, in the context of a dynamical model that accounts for most of the Earth's water as a product of collisions between the growing Earth and planet-sized 'embryos' from the asteroid belt. Mars' history is found to be different; to explain the present mass of Mars requires that it suffer essentially no giant collisions and the bulk of its growth is through addition of smaller bodies. Asteroids and comets from beyond 2.5 AU provide the source of Mars' water, which totals 6-27% of the Earth's present ocean (1 Earth ocean [equivalent to] 1.5 x [10.sup.21] kg), equivalent to 600-2700-m depth on the martian surface. The D/H ratio of this material is 1.2-1.6 times Standard Mean Ocean Water, the smaller value obtaining for the larger amount of water accreted. The upper half of the range of total water accreted, while many times less than that acquired by the Earth, is consistent with geological data on Mars, and the D/H value is that derived for martian magmatic water from SNC meteorites. Both together are consistent with published interpretations of the high D/H in present-day martian atmospheric water in terms of water loss through atmospheric escape. Keywords: Origin, Solar System; Mars, interior; Mars, atmosphere; Planetesimals

Published
2003

21. The Search for Nitrates on Mars by the Sample Analysis at Mars (SAM) Instrument

Author

Navarro-Gonzalez, Rafael, Stern, Jennifer C, Freissinet, Caroline, McKay, Chirstopher P, Sutter, Brad, Archer, P. Douglas, Jr, McAdam, Amy, Franz, Heather, Coll, Partice J, Glavin, Daniel Patrick, Eigenbrode, Jennifer L, Wong, Mike, Atreya, Sushiil K, Wray, James J, Steele, Andrew, Prats, Benito D, Szopa, Cyril, Coscia, David, Teinturier, Samuel, Buch, Arnaud, Leshin, Laurie A, Ming, Douglas W, Conrad, Pamela Gales, Cabane, Michel, Mahaffy, Paul R, and Grotzinger, John P

Subjects
Lunar And Planetary Science And Exploration
Abstract

Planetary models suggest that nitrogen was abundant in the early Martian atmosphere as N2 but it was lost by sputtering and photochemical loss to space, impact erosion, and chemical oxidation to nitrates. A nitrogen cycle may exist on Mars where nitrates, produced early in Mars' history, may have been later decomposed back into N2 by the current impact flux. Nitrates are a fundamental source of nitrogen for terrestrial microorganisms, and they have evolved metabolic pathways to perform both oxidation and reduction to drive a complete biological nitrogen cycle. Therefore, the characterization of nitrogen in Martian soils is important to assess habitability of the Martian environment, particularly with respect to the presence of nitrates. The only previous mission that was designed to search for soil nitrates was the Phoenix mission but N-containing species were not detected by TEGA or the MECA WCL. Nitrates have been tentatively identified in Nakhla meteorites, and if nitrogen was oxidized on Mars, this has important implications for the habitability potential of Mars. Here we report the results from the Sample Analysis at Mars (SAM) instrument suite aboard the Curiosity rover during the first year of surface operations in Gale Crater. Samples from the Rocknest aeolian deposit and sedimentary rocks (John Klein) were heated to approx 835degC under helium flow and the evolved gases were analyzed by MS and GC-MS. Two and possibly three peaks may be associated with the release of m/z 30 at temperatures ranging from 180degC to 500degC. M/z 30 has been tentatively identified as NO; other plausible contributions include CH2O and an isotopologue of CO, 12C18O. NO, CH2O, and CO may be reaction products of reagents (MTBSTFA/DMF) carried from Earth for the wet chemical derivatization experiments with SAM and/or derived from indigenous soil nitrogenated organics. Laboratory analyses indicate that it is also possible that <550degC evolved NO is produced via reaction of HCl with nitrates arising from the decomposition of perchlorates. All sources of m/z 30 whether it be martian or terrestrial will be considered and their implications for Mars will be discussed.

Published
2013

22. 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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23. Existence of an [sup.16]O-rich gaseous reservoir in the solar nebula. (Reports)

Author

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

Subjects
Nebulae -- Discovery and exploration, Science and technology, Discovery and exploration
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 [16.sup.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., Chondrite meteorites (chondrites) preserve records of physical and chemical processes that occurred during the earliest stages of solar system evolution. Chondrites are made up of three major components: refractory CAIs, [...]

Published
2002

24. Abundance and Isotopic Composition of Gases in the Martian Atmosphere: First Results from the Mars Curiosity Rover

Author

Mahaffy, Paul, Webster, Chris R, Atreya, Sushil K, Franz, Heather, Wong, Michael, Conrad, Pamela G, Harpold, Dan, Jones, John J, Leshin, Laurie, A, Manning, Heidi, Owen, Tobias, Pepin, Robert O, Squyres, Steven, and Trainer, Melissa

Subjects
Inorganic, Organic And Physical Chemistry, Lunar And Planetary Science And Exploration
Abstract

Repeated measurements of the composition of the Mars atmosphere from Curiosity Rover yield a (40)Ar/N2 ratio 1.7 times greater and the (40)Ar/(36)Ar ratio 1.6 times smaller than the Viking Lander values in 1976. The unexpected change in (40)Ar/N2 ratio probably results from different instrument characteristics although we cannot yet rule out some unknown atmospheric process. The new (40)Ar/(36)Ar ratio is more aligned with Martian meteoritic values. Besides Ar and N2 the Sample Analysis at Mars instrument suite on the Curiosity Rover has measured the other principal components of the atmosphere and the isotopes. The resulting volume mixing ratios are: CO2 0.960(+/- 0.007); (40)Ar 0.0193(+/- 0.0001); N2 0.0189(+/- 0.0003); O2 1.45(+/- 0.09) x 10(exp -3); and CO 5.45(+/- 3.62) x 10(exp 4); and the isotopes (40)Ar/(36)Ar 1.9(+/- 0.3) x 10(exp 3), and delta (13)C and delta (18)O from CO2 that are both several tens of per mil more positive than the terrestrial averages. Heavy isotope enrichments support the hypothesis of large atmospheric loss. Moreover, the data are consistent with values measured in Martian meteorites, providing additional strong support for a Martian origin for these rocks.

Published
2013

25. Support U.S. research during COVID-19

Author

Crow, Michael M., additional, Alger, Jonathan, additional, Amiridis, Michael, additional, Assanis, Dennis, additional, Barron, Eric, additional, Becker, Mark P., additional, Blank, Rebecca M., additional, Block, Gene D., additional, Bollinger, Lee C., additional, Brown, Robert A., additional, Burwell, Sylvia M., additional, Cassidy, C. Michael, additional, Clements, James P., additional, Currall, Steven, additional, DeGioia, John J., additional, Frenk, Julio, additional, Fuchs, W. Kent, additional, Gabel, Joan T. A., additional, Gallagher, Patrick D., additional, Gee, E. Gordon, additional, Isaacs, Eric, additional, Jacobs, Lloyd A., additional, Jahanian, Farnam, additional, Jenkins, John, additional, Johnson, Kristina M., additional, Kanter, Martha, additional, Kearns, Paul K., additional, Kennedy, Mark, additional, Khosla, Pradeep K., additional, Leshin, Laurie, additional, Lovell, Michael, additional, May, Gary S., additional, Morehead, Jere, additional, Myers, Richard B., additional, Proenza, Luis M., additional, Rose, Clayton, additional, Rudd, M. David, additional, Sands, Timothy D., additional, Schlissel, Mark S., additional, Stephens, Elisa, additional, Stroble, Elizabeth, additional, Subbaswamy, Kumble, additional, Tripathi, Satish, additional, Watkins, Ruth, additional, Weinberg, Adam, additional, Wilcox, Kim, additional, Wince-Smith, Deborah, additional, Wintersteen, Wendy, additional, Woodson, W. Randolph, additional, and Zimmer, Robert J., additional

Published
2020
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32. Investigation of Nebular Processes Through Oxygen Isotopic Analysis of Primitive Meteorite Materials

Author

Leshin, Laurie

Subjects
Lunar And Planetary Science And Exploration
Abstract

As a direct result of support provided by this grant, precise and accurate determination of delta(18)O and delta(17)O in silicates (and other minerals) by ion microprobe (both IMS 6f and IMS 1270) are now being carried out in several laboratories, and these analyses, combined with application of laser fluorination techniques, have led to a proliferation of oxygen isotopic data in the past approx. 3 years. The applications of these techniques in cosmochemical research have been myriad, from understanding the most refractory objects in the nebula (CAIs) to the low temperature alteration processes on meteorite parent bodies. Here, we describe our progress in understanding the oxygen isotopic microdistributions in primitive meteorite materials, as directly supported by this Origins grant.

Published
2002

33. Los Angeles: The Most Differentiated Basaltic Martian Meteorite

Author

Rubin, Alan E, Warren, Paul H, Greenwood, James P, Verish, Robert S, Leshin, Laurie A, Hervig, Richard L, Clayton, Robert N, and Mayeda, Toshiko K

Subjects
Astrophysics
Abstract

Los Angeles is a new martian meteorite that expands the compositional range of basaltic shergottites. Compared to Shergotty, Zagami, QUE94201, and EET79001-B, Los Angeles is more differentiated, with higher concentrations of incompatible elements (e.g., La) and a higher abundance of late-stage phases such as phosphates and K-rich feldspathic glass. The pyroxene crystallization trend starts at compositions more ferroan than in other martian basaits. Trace elements indicate a greater similarity to Shergotty and Zagami than to QUE94201 or EET79001-B, but the Mg/Fe ratio is low even compared to postulated parent melts of Shergotty and Zagami. Pyroxene in Los Angeles has 0.7-4-microns-thick exsolution lamellae, approx. 10 times thicker than those in Shergotty and Zaganii. Opaque oxide compositions suggest a low equilibration temperature at an oxygen fugacity near the fayafite-magnetitequartz buffer. Los Angeles cooled more slowly than Shergotty and Zagami. Slow cooling, coupled with the ferroan bulk composition, produced abundant fine-grained intergrowths of fayalite, hedenbergite, and silica, by the breakdown of pyroxferroite. Shock effects in Los Angeles include maskelynitized plagioclase, pyroxene with mosaic extinction, and rare fault zones. One such fault ruptured a previously decomposed zone of pyroxferroite. Although highly differentiated, the bulk composition of Los Angeles is not close to the low-Ca/Si composition or the globally wind-stirred soil of Mars.

Published
2000
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34. Isotopic Constraints on the Genesis of Carbonates in Martian Meteorite ALH 84001

Author

Leshin, Laurie A

Subjects
Astrophysics
Abstract

Oxygen isotopic analyses in approximately 20 micrometer spots in a chemically diverse suite of carbonates from ALH 84001 show highly variable delta(exp 18)O values from +5.4 to +25.3%. The isotopic data are correlated with the major element composition of the carbonate. The earliest forming (Ca-rich) carbonates have the lowest delta(exp 18)O values and the late-forming Mg-rich carbonates have the highest delta(exp 18)O values. Two models that can explain the isotopic variation were investigated. The carbonates could have formed in a water-rich environment at relatively low, but highly variable temperatures. In this open-system case the lower limit to the temperature variation is approximately 125 C, with fluctuations of over 250 C possible within the constraints of the model, depending on fluid composition. Alternatively the data can be explained by a closed-system model in which carbonates precipitated from a limited amount of a CO2-rich fluid. This scenario can reproduce the range of isotopic values observed, even at relatively high temperatures (greater than 500 C). Thus, the oxygen isotopic compositions do not provide unequivocal evidence for formation of the carbonates at low temperature. Neither of these scenarios is consistent with a biological origin of the carbonates and their associated features. Olivine from ALH 84001 occurs as clusters within orthopyroxene adjacent to fractures containing disrupted carbonate globules and feldspathic shock glass. The inclusions are irregular in shape and range in size from approximately 40 micrometers to submicrometer. The olivine exhibits a limited range of chemical composition from Fo(sub 65) to Fo(sub 66). We measured delta(exp 18)O values of the olivine to be +5.1 +/- 1.4%, indistinguishable within uncertainty from the host orthopyroxene. The data suggest that the olivine formed at high temperature (greater than 800 C), and is probably unrelated to carbonate formation. Instead the olivine probably formed by metamorphic reactions involving either dehydration of hydrous silicates or reduction of opx + spinel. If the reactions took place after carbonate formation, they could have caused devolatilization of siderite, producing the magnetite in the ALH carbonate globules. This scenario is also inconsistent with a biological origin for the features in ALH 84001.

Published
1999

35. Oxygen Isotopic Constraints on the Genesis of Carbonates from Martian Meteorite ALH84001

Author

Leshin, Laurie A, McKeegan, Kevin D, Carpenter, Paul K, and Harvey, Ralph P

Subjects
Lunar And Planetary Science And Exploration
Abstract

Ion microprobe oxygen isotopic measurements of a chemically diverse suite of carbonates from Martian meteorite ALH84001 are reported. The delta(sup 18)O values are highly variable, ranging from +5.4 to + 25.3%, and are correlated with major element compositions of the carbonate. The earliest forming (Ca-rich) carbonates have the lowest delta(sup 18)O values and the late-forming (Mg-rich) carbonates have the highest delta(sup 18)O values. Two models are presented which can explain the isotopic variations. The carbonates could have formed in a water rich environment at relatively low, but highly variable temperatures. In this open-system case the lower limit to the temperature variation is approx. 125 C, with fluctuations of over 250 C possible within the constraints of the model. Alternatively, the data can be explained by a closed-system model in which the carbonates precipitated from a limited amount of CO2-rich fluid. This scenario can reproduce the isotopic variations observed at a range of temperatures, including relatively high temperatures (less than 500 C). Thus the oxygen isotopic compositions do not provide unequivocal evidence for formation of the carbonates at low temperature. Although more information is needed in order to distinguish between the models, neither of the implied environments is consistent with biological activity. Thus, we suggest that features associated with the carbonates which have been interpreted to be the result of biological activity were most probably formed by inorganic processes.

Published
1998
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38. Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars

Author

Stern, Jennifer C., Sutter, Brad, Freissinet, Caroline, Navarro-González, Rafael, McKay, Christopher P., Archer, P. Douglas, Buch, Arnaud, Brunner, Anna E., Coll, Patrice, Eigenbrode, Jennifer L., Fairen, Alberto G., Franz, Heather B., Glavin, Daniel P., Kashyap, Srishti, McAdam, Amy C., Ming, Douglas W., Steele, Andrew, Szopa, Cyril, Wray, James J., Martín-Torres, F. Javier, Zorzano, Maria-Paz, Conrad, Pamela G., Mahaffy, Paul R., Kemppinen, Osku, Bridges, Nathan, Johnson, Jeffrey R., Minitti, Michelle, Cremers, David, Bell, James F., Edgar, Lauren, Farmer, Jack, Godber, Austin, Wadhwa, Meenakshi, Wellington, Danika, McEwan, Ian, Newman, Claire, Richardson, Mark, Charpentier, Antoine, Peret, Laurent, King, Penelope, Blank, Jennifer, Weigle, Gerald, Schmidt, Mariek, Li, Shuai, Milliken, Ralph, Robertson, Kevin, Sun, Vivian, Baker, Michael, Edwards, Christopher, Ehlmann, Bethany, Farley, Kenneth, Griffes, Jennifer, Grotzinger, John, Miller, Hayden, Newcombe, Megan, Pilorget, Cedric, Rice, Melissa, Siebach, Kirsten, Stack, Katie, Stolper, Edward, Brunet, Claude, Hipkin, Victoria, Léveillé, Richard, Marchand, Geneviève, Sánchez, Pablo Sobrón, Favot, Laurent, Cody, George, Flückiger, Lorenzo, Lees, David, Nefian, Ara, Martin, Mildred, Gailhanou, Marc, Westall, Frances, Israël, Guy, Agard, Christophe, Baroukh, Julien, Donny, Christophe, Gaboriaud, Alain, Guillemot, Philippe, Lafaille, Vivian, Lorigny, Eric, Paillet, Alexis, Pérez, René, Saccoccio, Muriel, Yana, Charles, Armiens-Aparicio, Carlos, Rodríguez, Javier Caride, Blázquez, Isaías Carrasco, Gómez, Felipe Gómez, Gómez-Elvira, Javier, Hettrich, Sebastian, Malvitte, Alain Lepinette, Jiménez, Mercedes Marín, Martínez-Frías, Jesús, Martín-Soler, Javier, Torres, F. Javier Martín, Jurado, Antonio Molina, Mora-Sotomayor, Luis, Caro, Guillermo Muñoz, López, Sara Navarro, Peinado-González, Verónica, Pla-García, Jorge, Manfredi, José Antonio Rodriguez, Romeral-Planelló, Julio José, Fuentes, Sara Alejandra Sans, Martinez, Eduardo Sebastian, Redondo, Josefina Torres, Urqui-O'Callaghan, Roser, Mier, María-Paz Zorzano, Chipera, Steve, Lacour, Jean-Luc, Mauchien, Patrick, Sirven, Jean-Baptiste, Manning, Heidi, Fairén, Alberto, Hayes, Alexander, Joseph, Jonathan, Squyres, Steven, Sullivan, Robert, Thomas, Peter, Dupont, Audrey, Lundberg, Angela, Melikechi, Noureddine, Mezzacappa, Alissa, DeMarines, Julia, Grinspoon, David, Reitz, Günther, Prats, Benito, Atlaskin, Evgeny, Genzer, Maria, Harri, Ari-Matti, Haukka, Harri, Kahanpää, Henrik, Kauhanen, Janne, Paton, Mark, Polkko, Jouni, Schmidt, Walter, Siili, Tero, Fabre, Cécile, Wray, James, Wilhelm, Mary Beth, Poitrasson, Franck, Patel, Kiran, Gorevan, Stephen, Indyk, Stephen, Paulsen, Gale, Gupta, Sanjeev, Bish, David, Schieber, Juergen, Gondet, Brigitte, Langevin, Yves, Geffroy, Claude, Baratoux, David, Berger, Gilles, Cros, Alain, d’Uston, Claude, Forni, Olivier, Gasnault, Olivier, Lasue, Jérémie, Lee, Qiu-Mei, Maurice, Sylvestre, Meslin, Pierre-Yves, Pallier, Etienne, Parot, Yann, Pinet, Patrick, Schröder, Susanne, Toplis, Mike, Lewin, Éric, Brunner, Will, Heydari, Ezat, Achilles, Cherie, Oehler, Dorothy, Cabane, Michel, Coscia, David, Dromart, Gilles, Robert, François, Sautter, Violaine, Le Mouélic, Stéphane, Mangold, Nicolas, Nachon, Marion, Stalport, Fabien, François, Pascaline, Raulin, François, Teinturier, Samuel, Cameron, James, Clegg, Sam, Cousin, Agnès, DeLapp, Dorothea, Dingler, Robert, Jackson, Ryan Steele, Johnstone, Stephen, Lanza, Nina, Little, Cynthia, Nelson, Tony, Wiens, Roger C., Williams, Richard B., Jones, Andrea, Kirkland, Laurel, Treiman, Allan, Baker, Burt, Cantor, Bruce, Caplinger, Michael, Davis, Scott, Duston, Brian, Edgett, Kenneth, Fay, Donald, Hardgrove, Craig, Harker, David, Herrera, Paul, Jensen, Elsa, Kennedy, Megan R., Krezoski, Gillian, Krysak, Daniel, Lipkaman, Leslie, Malin, Michael, McCartney, Elaina, McNair, Sean, Nixon, Brian, Posiolova, Liliya, Ravine, Michael, Salamon, Andrew, Saper, Lee, Stoiber, Kevin, Supulver, Kimberley, Van Beek, Jason, Van Beek, Tessa, Zimdar, Robert, French, Katherine Louise, Iagnemma, Karl, Miller, Kristen, Summons, Roger, Goesmann, Fred, Goetz, Walter, Hviid, Stubbe, Johnson, Micah, Lefavor, Matthew, Lyness, Eric, Breves, Elly, Dyar, M. Darby, Fassett, Caleb, Blake, David F., Bristow, Thomas, DesMarais, David, Edwards, Laurence, Haberle, Robert, Hoehler, Tori, Hollingsworth, Jeff, Kahre, Melinda, Keely, Leslie, McKay, Christopher, Bleacher, Lora, Brinckerhoff, William, Choi, David, Conrad, Pamela, Dworkin, Jason P., Eigenbrode, Jennifer, Floyd, Melissa, Garvin, James, Glavin, Daniel, Harpold, Daniel, Mahaffy, Paul, Martin, David K., McAdam, Amy, Pavlov, Alexander, Raaen, Eric, Smith, Michael D., Stern, Jennifer, Tan, Florence, Trainer, Melissa, Meyer, Michael, Posner, Arik, Voytek, Mary, Anderson, Robert C, Aubrey, Andrew, Beegle, Luther W., Behar, Alberto, Blaney, Diana, Brinza, David, Calef, Fred, Christensen, Lance, Crisp, Joy A., DeFlores, Lauren, Feldman, Jason, Feldman, Sabrina, Flesch, Gregory, Hurowitz, Joel, Jun, Insoo, Keymeulen, Didier, Maki, Justin, Mischna, Michael, Morookian, John Michael, Parker, Timothy, Pavri, Betina, Schoppers, Marcel, Sengstacken, Aaron, Simmonds, John J., Spanovich, Nicole, Juarez, Manuel de la Torre, Vasavada, Ashwin R., Webster, Christopher R., Yen, Albert, Archer, Paul Douglas, Cucinotta, Francis, Jones, John H., Ming, Douglas, Morris, Richard V., Niles, Paul, Rampe, Elizabeth, Nolan, Thomas, Fisk, Martin, Radziemski, Leon, Barraclough, Bruce, Bender, Steve, Berman, Daniel, Dobrea, Eldar Noe, Tokar, Robert, Vaniman, David, Williams, Rebecca M. E., Yingst, Aileen, Lewis, Kevin, Leshin, Laurie, Cleghorn, Timothy, Huntress, Wesley, Manhès, Gérard, Hudgins, Judy, Olson, Timothy, Stewart, Noel, Sarrazin, Philippe, Grant, John, Vicenzi, Edward, Wilson, Sharon A., Bullock, Mark, Ehresmann, Bent, Hamilton, Victoria, Hassler, Donald, Peterson, Joseph, Rafkin, Scot, Zeitlin, Cary, Fedosov, Fedor, Golovin, Dmitry, Karpushkina, Natalya, Kozyrev, Alexander, Litvak, Maxim, Malakhov, Alexey, Mitrofanov, Igor, Mokrousov, Maxim, Nikiforov, Sergey, Prokhorov, Vasily, Sanin, Anton, Tretyakov, Vladislav, Varenikov, Alexey, Vostrukhin, Andrey, Kuzmin, Ruslan, Clark, Benton, Wolff, Michael, McLennan, Scott, Botta, Oliver, Drake, Darrell, Bean, Keri, Lemmon, Mark, Schwenzer, Susanne P., Anderson, Ryan B., Herkenhoff, Kenneth, Lee, Ella Mae, Sucharski, Robert, Hernández, Miguel Ángel de Pablo, Ávalos, Juan José Blanco, Ramos, Miguel, Kim, Myung-Hee, Malespin, Charles, Plante, Ianik, Muller, Jan-Peter, Ewing, Ryan, Boynton, William, Downs, Robert, Fitzgibbon, Mike, Harshman, Karl, Morrison, Shaunna, Dietrich, William, Kortmann, Onno, Palucis, Marisa, Sumner, Dawn Y., Williams, Amy, Lugmair, Günter, Wilson, Michael A., Rubin, David, Jakosky, Bruce, Balic-Zunic, Tonci, Frydenvang, Jens, Jensen, Jaqueline Kløvgaard, Kinch, Kjartan, Koefoed, Asmus, Madsen, Morten Bo, Stipp, Susan Louise Svane, Boyd, Nick, Campbell, John L., Gellert, Ralf, Perrett, Glynis, Pradler, Irina, VanBommel, Scott, Jacob, Samantha, Owen, Tobias, Rowland, Scott, Savijärvi, Hannu, Boehm, Eckart, Böttcher, Stephan, Burmeister, Sönke, Guo, Jingnan, Köhler, Jan, García, César Martín, Mueller-Mellin, Reinhold, Wimmer-Schweingruber, Robert, Bridges, John C., McConnochie, Timothy, Benna, Mehdi, Franz, Heather, Bower, Hannah, Brunner, Anna, Blau, Hannah, Boucher, Thomas, Carmosino, Marco, Atreya, Sushil, Elliott, Harvey, Halleaux, Douglas, Rennó, Nilton, Wong, Michael, Pepin, Robert, Elliott, Beverley, Spray, John, Thompson, Lucy, Gordon, Suzanne, Newsom, Horton, Ollila, Ann, Williams, Joshua, Vasconcelos, Paulo, Bentz, Jennifer, Nealson, Kenneth, Popa, Radu, Kah, Linda C., Moersch, Jeffrey, Tate, Christopher, Day, Mackenzie, Kocurek, Gary, Hallet, Bernard, Sletten, Ronald, Francis, Raymond, McCullough, Emily, Cloutis, Ed, ten Kate, Inge Loes, Arvidson, Raymond, Fraeman, Abigail, Scholes, Daniel, Slavney, Susan, Stein, Thomas, Ward, Jennifer, Berger, Jeffrey, Moores, John E., NASA Goddard Space Flight Center (GSFC), NASA Johnson Space Center (JSC), NASA, Laboratorio de Química de Plasmas y Estudios Planetarios [Mexico], Instituto de Ciencias Nucleares [Mexico], Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM)-Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), NASA Ames Research Center (ARC), Laboratoire de Génie des Procédés et Matériaux - EA 4038 (LGPM), CentraleSupélec, ASU School of Earth and Space Exploration (SESE), Arizona State University [Tempe] (ASU), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy [Ithaca], Cornell University [New York], Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Center for Research and Exploration in Space Science and Technology [GSFC] (CRESST), Centre de Recherche Public Henri Tudor [Technoport] (CRP Henri Tudor), Centre de Recherche Public Henri-Tudor [Luxembourg] (CRP Henri-Tudor), Department of Microbiology [Amherst], University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS)-University of Massachusetts System (UMASS), Astromaterials Research and Exploration Science (ARES), NASA-NASA, Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], Instituto Andaluz de Ciencias de la Tierra (IACT), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de Granada (UGR), Department of Computer Science, Electrical and Space Engineering [Luleå], Luleå University of Technology (LUT), Universidad Nacional Autónoma de México (UNAM)-Universidad Nacional Autónoma de México (UNAM), Carnegie Institution for Science [Washington], Universidad de Granada (UGR)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Cornell University, Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Department of Microbiology, IMPEC - LATMOS, Universidad de Granada (UGR)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), and Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de Granada = University of Granada (UGR)

Subjects
Martian, Multidisciplinary, 010504 meteorology & atmospheric sciences, Water on Mars, nitrates, astrobiology, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Mars, Mars Exploration Program, 01 natural sciences, nitrogen, Astrobiology, Curiosity, 13. Climate action, Rocknest, 0103 physical sciences, Sample Analysis at Mars, Physical Sciences, Aeolian processes, Composition of Mars, 010303 astronomy & astrophysics, Nitrogen cycle, Geology, 0105 earth and related environmental sciences
Abstract

International audience; The Sample Analysis at Mars (SAM) investigation on the Mars Science Laboratory (MSL) Curiosity rover has detected oxidized nitrogen-bearing compounds during pyrolysis of scooped aeolian sediments and drilled sedimentary deposits within Gale crater. Total N concentrations ranged from 20 to 250 nmol N per sample. After subtraction of known N sources in SAM, our results support the equivalent of 110–300 ppm of nitrate in the Rocknest (RN) aeolian samples, and 70–260 and 330–1,100 ppm nitrate in John Klein (JK) and Cumberland (CB) mudstone deposits, respectively. Discovery of indigenous martian nitrogen in Mars surface materials has important implications for habitability and, specifically, for the potential evolution of a nitrogen cycle at some point in martian history. The detection of nitrate in both wind-drifted fines (RN) and in mudstone (JK, CB) is likely a result of N2 fixation to nitrate generated by thermal shock from impact or volcanic plume lightning on ancient Mars. Fixed nitrogen could have facilitated the development of a primitive nitrogen cycle on the surface of ancient Mars, potentially providing a biochemically accessible source of nitrogen.

Published
2015
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39. Chemistry of fracture-filling raised ridges in Yellowknife Bay, Gale Crater: Window into past aqueous activity and habitability on Mars

Author

Leveille, 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, Maurice, Sylvestre, Newsom, Horton, Canadian Space Agency (CSA), Space Research Centre [Leicester], University of Leicester, Los Alamos National Laboratory (LANL), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institute of Meteoritics [Albuquerque] (IOM), The University of New Mexico [Albuquerque], Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Faculté de Pharmacie [Bruxelles] (ULB), Université libre de Bruxelles (ULB), GeoRessources, Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Institut national des sciences de l'Univers (INSU - CNRS), Astrogeology Science Center [Flagstaff], United States Geological Survey [Reston] (USGS), Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Rensselaer Polytechnic Institute (RPI), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), and NASA-California Institute of Technology (CALTECH)

Subjects
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract

International audience; The ChemCam instrument package on the Curiosity rover was used to characterize distinctive raised ridges in the Sheepbed mudstone, Yellowknife Bay formation, Gale Crater. The multilayered, fracture-filling ridges are more resistant to erosion than the Sheepbed mudstone rock in which they occur. The bulk average composition of the raised ridges is enriched in MgO by 1.2-1.7 times (average of 8.3-11.4 wt %; single-shot maximum of 17.0 wt %) over that of the mudstone. Al2O3 is anticorrelated with MgO, while Li is somewhat enriched where MgO is highest. Some ridges show a variation in composition with different layers on a submillimeter scale. In particular, the McGrath target shows similar high-MgO resistant outer layers and a low-MgO, less resistant inner layer. This is consistent with the interpretation that the raised ridges are isopachous fracture-filling cements with a stratigraphy that likely reveals changes in fluid composition or depositional conditions over time. Overall, the average composition of the raised ridges is close to that of a Mg- and Fe-rich smectite, or saponite, which may also be the main clay mineral constituent of the host mudstone. These analyses provide evidence of diagenesis and aqueous activity in the early postdepositional history of the Yellowknife Bay formation, consistent with a low salinity to brackish fluid at near-neutral or slightly alkaline pH. The fluids that circulated through the fractures likely interacted with the Sheepbed mudstone and (or) other stratigraphically adjacent rock units of basaltic composition and leached Mg from them preferentially.

Published
2014
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40. Primordial argon isotope fractionation in the atmosphere of Mars measured by the SAM instrument on Curiosity and implications for atmospheric loss

Author

Atreya, Sushil K., Trainer, Melissa G., Franz, Heather B., Wong, Michael H., Manning, Heidi L. K., Malespin, Charles A., Mahaffy, Paul R., Conrad, Pamela G., Brunner, Anna E., Leshin, Laurie A., Jones, John H., Webster, Christopher R., Owen, Tobias C., Pepin, Robert O., and Navarro-González, R.

Abstract

The quadrupole mass spectrometer of the Sample Analysis at Mars (SAM) instrument on Curiosity rover has made the first high-precision measurement of the nonradiogenic argon isotope ratio in the atmosphere of Mars. The resulting value of ³⁶Ar/³⁸Ar = 4.2 ± 0.1 is highly significant for it provides excellent evidence that “Mars” meteorites are indeed of Martian origin, and it points to a significant loss of argon of at least 50% and perhaps as high as 85–95% from the atmosphere of Mars in the past 4 billion years. Taken together with the isotopic fractionations in N, C, H, and O measured by SAM, these results imply a substantial loss of atmosphere from Mars in the posthydrodynamic escape phase.

Published
2013

41. Isotope ratios of H, C, and O in CO₂ and H₂O 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, Steele, Andrew and the MSL Science Team, Achilles, Cherie, Agard, Christophe, Alves Verdasca, José Alexandre, Anderson, Robert, Anderson, Ryan, Archer, Doug, Armiens-Aparicio, Carlos, Arvidson, Ray, Atlaskin, Evgeny, Aubrey, Andrew, Baker, Burt, Baker, Michael, Balic-Zunic, Tonci, Baratoux, David, Baroukh, Julien, Barraclough, Bruce, Bean, Keri, Beegle, Luther, Behar, Alberto, Bell, James, Bender, Steve, Benna, Mehdi, Bentz, Jennifer, Berger, Gilles, Berger, Jeff, Berman, Daniel, Bish, David, Blake, David F, Blanco Avalos, Juan J, Blaney, Diana, Blank, Jen, Blau, Hannah, Bleacher, Lora, Boehm, Eckart, Botta, Oliver, Böttcher, Stephan, Boucher, Thomas, Bower, Hannah, Boyd, Nick, Boynton, Bill, Breves, Elly, Bridges, John, Bridges, Nathan, Brinckerhoff, William, Brinza, David, Bristow, Thomas, Brunet, Claude, Brunner, Anna, Brunner, Will, Buch, Arnaud, Bullock, Mark, Burmeister, Sönke, Cabane, Michel, Calef, Fred, Cameron, James, Campbell, John, Cantor, Bruce, Caplinger, Michael, Caride Rodríguez, Javier, Carmosino, Marco, Carrasco Blázquez, Isaías, Charpentier, Antoine, Chipera, Steve, Choi, David, Clark, Benton, Clegg, Sam, Cleghorn, Timothy, Cloutis, Ed, Cody, George, Coll, Patrice, Conrad, Pamela, Coscia, David, Cousin, Agnès, Cremers, David, Crisp, Joy, Cros, Alain, Cucinotta, Frank, d'Uston, Claude, Davis, Scott, Day, Mackenzie, de la Torre Juarez, Manuel, DeFlores, Lauren, DeLapp, Dorothea, DeMarines, Julia, DesMarais, David, Dietrich, William, Dingler, Robert, Donny, Christophe, Downs, Bob, Drake, Darrell, Dromart, Gilles, Dupont, Audrey, Duston, Brian, Dworkin, Jason, Dyar, M Darby, Edgar, Lauren, Edgett, Kenneth, Edwards, Christopher, Edwards, Laurence, Ehlmann, Bethany, Ehresmann, Bent, Eigenbrode, Jen, Elliott, Beverley, Elliott, Harvey, Ewing, Ryan, Fabre, Cécile, Fairén, Alberto, Farley, Ken, Farmer, Jack, Fassett, Caleb, Favot, Laurent, Fay, Donald, Fedosov, Fedor, Feldman, Jason, Feldman, Sabrina, Fisk, Marty, Fitzgibbon, Mike, Floyd, Melissa, Flückiger, Lorenzo, Forni, Olivier, Fraeman, Abby, Francis, Raymond, François, Pascaline, Freissinet, Caroline, French, Katherine Louise, Frydenvang, Jens, Gaboriaud, Alain, Gailhanou, Marc, Garvin, James, Gasnault, Olivier, Geffroy, Claude, Gellert, Ralf, Genzer, Maria, Glavin, Daniel, Godber, Austin, Goesmann, Fred, Goetz, Walter, Golovin, Dmitry, Gómez Gómez, Felipe, Gómez-Elvira, Javier, Gondet, Brigitte, Gordon, Suzanne, Gorevan, Stephen, Grant, John, Griffes, Jennifer, Grinspoon, David, Grotzinger, John, Guillemot, Philippe, Guo, Jingnan, Gupta, Sanjeev, Guzewich, Scott, Haberle, Robert, Halleaux, Douglas, Hallet, Bernard, Hamilton, Vicky, Hardgrove, Craig, Harker, David, Harpold, Daniel, Harri, Ari-Matti, Harshman, Karl, Hassler, Donald, Haukka, Harri, Hayes, Alex, Herkenhoff, Ken, Herrera, Paul, Hettrich, Sebastian, Heydari, Ezat, Hipkin, Victoria, Hoehler, Tori, Hollingsworth, Jeff, Hudgins, Judy, Huntress, Wesley, Hurowitz, Joel, Hviid, Stubbe, Iagnemma, Karl, Indyk, Steve, Israël, Guy, Jackson, Ryan, Jacob, Samantha, Jakosky, Bruce, Jensen, Elsa, Jensen, Jaqueline Kløvgaard, Johnson, Jeffrey, Johnson, Micah, Johnstone, Steve, Jones, Andrea, Joseph, Jonathan, Jun, Insoo, Kah, Linda, Kahanpää, Henrik, Kahre, Melinda, Karpushkina, Natalya, Kasprzak, Wayne, Kauhanen, Janne, Keely, Leslie, Kemppinen, Osku, Keymeulen, Didier, Kim, Myung-Hee, Kinch, Kjartan, King, Penny, Kirkland, Laurel, Kocurek, Gary, Koefoed, Asmus, Köhler, Jan, Kortmann, Onno, Kozyrev, Alexander, Krezoski, Jill, Krysak, Daniel, Kuzmin, Ruslan, Lacour, Jean Luc, Lafaille, Vivian, Langevin, Yves, Lanza, Nina, Lasue, Jeremie, Le Mouélic, Stéphane, Lee, Ella Mae, Lee, Qiu-Mei, Lees, David, Lefavor, Matthew, Lemmon, Mark, Lepinette Malvitte, Alain, Léveillé, Richard, Lewin-Carpintier, Éric, Lewis, Kevin, Li, Shuai, Lipkaman, Leslie, Little, Cynthia, Litvak, Maxim, Lorigny, Eric, Lugmair, Guenter, Lundberg, Angela, Lyness, Eric, Madsen, Morten, Maki, Justin, Malakhov, Alexey, Malespin, Charles, Malin, Michael, Mangold, Nicolas, Manhes, Gérard, Manning, Heidi, Marchand, Geneviève, Marín Jiménez, Mercedes, Martín García, César, Martin, Dave, Martin, Mildred, Martínez-Frías, Jesús, Martín-Soler, Javier, Martín-Torres, F Javier, Mauchien, Patrick, Maurice, Sylvestre, McAdam, Amy, McCartney, Elaina, McConnochie, Timothy, McCullough, Emily, McEwan, Ian, McKay, Christopher, McLennan, Scott, McNair, Sean, Melikechi, Noureddine, Meslin, Pierre-Yves, Meyer, Michael, Mezzacappa, Alissa, Miller, Hayden, Miller, Kristen, Milliken, Ralph, Ming, Douglas, Minitti, Michelle, Mischna, Michael, Mitrofanov, Igor, Moersch, Jeff, Mokrousov, Maxim, Molina Jurado, Antonio, Moores, John, Mora-Sotomayor, Luis, Morookian, John Michael, Morris, Richard, Morrison, Shaunna, Mueller-Mellin, Reinhold, Muller, Jan-Peter, Muñoz Caro, Guillermo, Nachon, Marion, Navarro López, Sara, Navarro-González, Rafael, Nealson, Kenneth, Nefian, Ara, Nelson, Tony, Newcombe, Megan, Newman, Claire, Newsom, Horton, Nikiforov, Sergey, Nixon, Brian, Noe Dobrea, Eldar, Nolan, Thomas, Oehler, Dorothy, Ollila, Ann, Olson, Timothy, de Pablo Hernández, Miguel Ángel, Paillet, Alexis, Pallier, Etienne, Palucis, Marisa, Parker, Timothy, Parot, Yann, Patel, Kiran, Paton, Mark, Paulsen, Gale, Pavlov, Alex, Pavri, Betina, Peinado-González, Verónica, Peret, Laurent, Perez, Rene, Perrett, Glynis, Peterson, Joe, Pilorget, Cedric, Pinet, Patrick, Pla-García, Jorge, Plante, Ianik, Poitrasson, Franck, Polkko, Jouni, Popa, Radu, Posiolova, Liliya, Posner, Arik, Pradler, Irina, Prats, Benito, Prokhorov, Vasily, Purdy, Sharon Wilson, Raaen, Eric, Radziemski, Leon, Rafkin, Scot, Ramos, Miguel, Rampe, Elizabeth, Raulin, François, Ravine, Michael, Reitz, Günther, Rennó, Nilton, Rice, Melissa, Richardson, Mark, Robert, François, Robertson, Kevin, Rodriguez Manfredi, José Antonio, Romeral-Planelló, Julio J, Rowland, Scott, Rubin, David, Saccoccio, Muriel, Salamon, Andrew, Sandoval, Jennifer, Sanin, Anton, Sans Fuentes, Sara Alejandra, Saper, Lee, Sarrazin, Philippe, Sautter, Violaine, Savijärvi, Hannu, Schieber, Juergen, Schmidt, Mariek, Schmidt, Walter, Scholes, Daniel, Schoppers, Marcel, Schröder, Susanne, Schwenzer, Susanne, Sebastian Martinez, Eduardo, Sengstacken, Aaron, Shterts, Ruslan, Siebach, Kirsten, Siili, Tero, Simmonds, Jeff, Sirven, Jean-Baptiste, Slavney, Susie, Sletten, Ronald, Smith, Michael, Sobrón Sánchez, Pablo, Spanovich, Nicole, Spray, John, Squyres, Steven, Stack, Katie, Stalport, Fabien, Stein, Thomas, Stewart, Noel, Stipp, Susan Louise Svane, Stoiber, Kevin, Stolper, Ed, Sucharski, Bob, Sullivan, Rob, Summons, Roger, Sumner, Dawn, Sun, Vivian, Supulver, Kimberley, Sutter, Brad, Szopa, Cyril, Tan, Florence, Tate, Christopher, Teinturier, Samuel, ten Kate, Inge, Thomas, Peter, Thompson, Lucy, Tokar, Robert, Toplis, Mike, Torres Redondo, Josefina, Trainer, Melissa, Treiman, Allan, Tretyakov, Vladislav, Urqui-O'Callaghan, Roser, Van Beek, Jason, Van Beek, Tessa, VanBommel, Scott, Vaniman, David, Varenikov, Alexey, Vasavada, Ashwin, Vasconcelos, Paulo, Vicenzi, Edward, Vostrukhin, Andrey, Voytek, Mary, Wadhwa, Meenakshi, Ward, Jennifer, Weigle, Eddie, Wellington, Danika, Westall, Frances, Wiens, Roger Craig, Wilhelm, Mary Beth, Williams, Amy, Williams, Joshua, Williams, Rebecca, Williams, Richard B, Wilson, Mike, Wimmer-Schweingruber, Robert, Wolff, Mike, Wong, Mike, Wray, James, Wu, Megan, Yana, Charles, Yen, Albert, Yingst, Aileen, Zeitlin, Cary, Zimdar, Robert, and Zorzano Mier, María-Paz

Subjects
isotope ratios, MSL-Radiation, Mars
Published
2013

42. 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, Douglas Archer Jr., P., 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-González, Rafael, Pavlov, Alexander, Steele, Andrew, Summons, Roger E., Szopa, Cyril, Teinturier, Samuel, Mahaffy, Paul R., NASA Goddard Space Flight Center (GSFC), Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), Center for Research and Exploration in Space Science and Technology [GSFC] (CRESST), Laboratoire de Génie des Procédés et Matériaux - EA 4038 (LGPM), CentraleSupélec, NASA Johnson Space Center (JSC), NASA, Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), California Institute of Technology (CALTECH), Rensselaer Polytechnic Institute (RPI), Catholic University of America, NASA Ames Research Center (ARC), Laboratorio de Química de Plasmas y Estudios Planetarios [Mexico], Instituto de Ciencias Nucleares [Mexico], Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM)-Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México (UNAM)-Universidad Nacional Autónoma de México (UNAM), Carnegie Institution for Science [Washington], IMPEC - LATMOS, and Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Sample Analysis at Mars, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Mars Science Laboratory, MTBSTFA, perchlorates, chlorohydrocarbons, Rocknest soil
Abstract

International audience; A single scoop of the Rocknest aeolian deposit was sieved (2 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
Full Text
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44. LAURIE LESHIN.

Author

Leshin, Laurie

Subjects
*PLANETARY exploration
Abstract

The article discusses U.S. National Aeronautics & Space Administration's Europa Clipper mission, which aims to explore Jupiter's moon Europa for signs of life in its subsurface ocean, featuring an original poem by U.S. Poet Laureate Ada Limón engraved on the spacecraft.

Published
2023

45. Comet 81P/Wild 2 Under a Microscope

Author

Brownlee, Don, Tsou, Peter, Aleon, Jerome, 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, Horz, 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, Luening, 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, Takashi, Mostefaoui, Smail, Nakamura, Tomoki, Nakano, T., Newville, M., ittler, Larry R., Ohnishi, Ichiro, Ohsumi, Kazumasa, 奥平, 恭子, Papanastassiou, Dimitri A., Palma, Russ, Palumbo, Maria E., Pepin, Robert O., Perkins, David, Perronnet, Murielle, Pianetta, P., Rao, William, Rietmeijer, Frans J. M., Robert, Francois, 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-Rodriguez, 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, 矢野, 創, Young, Edward D., Zare, Richard N., Zega, Thomas, Ziegler, Karen, Zimmerman, Laurent, Zinner, Ernst, Zolensky, Michael, Okudaira, Kyoko, Yano, Hajime, Brownlee, Don, Tsou, Peter, Aleon, Jerome, 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, Horz, 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, Luening, 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, Takashi, Mostefaoui, Smail, Nakamura, Tomoki, Nakano, T., Newville, M., ittler, Larry R., Ohnishi, Ichiro, Ohsumi, Kazumasa, 奥平, 恭子, Papanastassiou, Dimitri A., Palma, Russ, Palumbo, Maria E., Pepin, Robert O., Perkins, David, Perronnet, Murielle, Pianetta, P., Rao, William, Rietmeijer, Frans J. M., Robert, Francois, 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-Rodriguez, 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, 矢野, 創, Young, Edward D., Zare, Richard N., Zega, Thomas, Ziegler, Karen, Zimmerman, Laurent, Zinner, Ernst, Zolensky, Michael, Okudaira, Kyoko, and Yano, Hajime

Abstract

著者人数: 183名

Published
2015

47. ³⁶Cl,²⁶Al, and O isotopes in an Allende type B2 CAI: Implications for multiple secondary alteration events in the early solar system

Author

Ushikubo, Takayuki, Guan, Yunbin, Hiyagon, Hajime, Sugiura, Naoji, and Leshin, Laurie A.

Abstract

We measured ³⁶Cl-36³⁶S and ²⁶Al-²⁶Mg systematics and O isotopes of secondary phases in a moderately altered type B2 CAI (CAI#2) from the Allende CV3 chondrite. CAI#2 has two distinct alteration domains: the anorthite-grossular (An-Grs) domain that mostly consists of anorthite and grossular, and the Na-rich domain that mostly consists of sodalite, anorthite, and Fe-bearing phases. Large ³⁶S excesses (up to ∼400‰) corresponding to an initial ³⁶Cl/³⁵Cl ratio of (1.4 ± 0.3) × 10⁻⁶ were observed in sodalite of the Na-rich domain, but no resolvable ²⁶Mg excesses were observed in anorthite and sodalite of the Na-rich domain (the initial ²⁶Al/²⁷Al ratio < 4.4 × 10⁻⁷). If we assume that the ³⁶Cl-³⁶S and the ²⁶Al-²⁶Mg systematics were closed simultaneously, the ³⁶Cl/³⁵Cl ratio would have to be on the order of ∼10⁻² when CAIs were formed. In contrast to sodalite in Na-rich domain, significant ²⁶Mg excesses (up to ∼35‰) corresponding to an initial ²⁶Al/²⁷Al ratio of (1.2 ± 0.2) × 10⁻⁵ were identified in anorthite of the An-Grs domain. The ²⁶Al-²⁶Mg systematics of secondary phases in CAI#2 suggest that CAIs experienced multiple alteration events. Some of the alteration processes occurred while ³⁶Cl (half-life is 0.3 Myr) and ²⁶Al (half-life is 0.72 Myr) were still alive, whereas others took place much later. Assuming that ²⁶Al was homogeneously distributed in the solar nebula, our study implies that alteration of CAIs occurred as early as within 1.5 Myr of CAI formation and as late as 5.7 Myr after.

Published
2007

48. Oxygen isotope and ²⁶Al-²⁶Mg systematics of aluminum-rich chondrules from unequilibrated enstatite chondrites

Author

Guan, Yunbin, Huss, Gary R., Leshin, Laurie A., MacPherson, Glenn J., and McKeegan, Kevin D.

Abstract

Correlated in situ analyses of the oxygen and magnesium isotopic compositions of aluminum-rich chondrules from unequilibrated enstatite chondrites were obtained using an ion microprobe. Among eleven aluminum-rich chondrules and two plagioclase fragments measured for ²⁶Al-²⁶Mg systematics, only one aluminum-rich chondrule contains excess ²⁶Mg from the in situ decay of ²⁶Al; the inferred initial ratio (²⁶Al/²⁷Al)ₒ = (6.8 ± 2.4) × 10⁻⁶ is consistent with ratios observed in chondrules from carbonaceous chondrites and unequilibrated ordinary chondrites. The oxygen isotopic compositions of five aluminum-rich chondrules and one plagioclase fragment define a line of slope ˜0.6 ± 0.1 on a three-oxygen-isotope diagram, overlapping the field defined by ferromagnesian chondrules in enstatite chondrites but extending to more ¹⁶O-rich compositions with a range in δ¹⁸O of about ˜12‰. Based on their oxygen isotopic compositions, aluminum-rich chondrules in unequilibrated enstatite chondrites are probably genetically related to ferromagnesian chondrules and are not simple mixtures of materials from ferromagnesian chondrules and calcium-aluminum-rich inclusions (CAIs). Relative to their counterparts from unequilibrated ordinary chondrites, aluminum-rich chondrules from unequilibrated enstatite chondrites show a narrower oxygen isotopic range and much less resolvable excess ²⁶Mg from the in situ decay of ²⁶Al, probably resulting from higher degrees of equilibration and isotopic exchange during post-crystallization metamorphism. However, the presence of ²⁶Al-bearing chondrules within the primitive ordinary, carbonaceous, and now enstatite chondrites suggests that ²⁶Al was at least approximately homogeneously distributed across the chondrite-forming region.

Published
2006

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