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1. Gas phase Elemental abundances in Molecular cloudS (GEMS) VII. Sulfur elemental abundance

Author

Fuente, A., Rivière-Marichalar, P., Beitia-Antero, L., Caselli, P., Wakelam, V., Esplugues, G., Rodríguez-Baras, M., Navarro-Almaida, D., Gerin, M., Kramer, C., Bachiller, R., Goicoechea, J. R., Jiménez-Serra, I., Loison, J. C., Ivlev, A., Martín-Doménech, R., Spezzano, S., Roncero, O., Muñoz-Caro, G., Cazaux, S., and Marcelino, N.

Subjects
Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics
Abstract

Gas phase Elemental abundances in molecular CloudS (GEMS) is an IRAM 30m large program aimed at determining the elemental abundances of carbon (C), oxygen (O), nitrogen (N), and sulfur (S) in a selected set of prototypical star-forming filaments. In particular, the elemental abundance of S remains uncertain by several orders of magnitude and its determination is one of the most challenging goals of this program. We have carried out an extensive chemical modeling of the fractional abundances of CO, HCO$^+$, HCN, HNC, CS, SO, H$_2$S, OCS, and HCS$^+$ to determine the sulfur depletion toward the 244 positions in the GEMS database. These positions sample visual extinctions from A$_V$ $\sim$ 3 mag to $>$50 mag, molecular hydrogen densities ranging from a few 10$^3$~cm$^{-3}$ to 3$\times$10$^6$~cm$^{-3}$, and T$_k$ $\sim$ 10$-$35 K. Most of the positions in Taurus and Perseus are best fitted assuming early-time chemistry, t=0.1 Myr, $\zeta_{H_2}$$\sim$ (0.5$-$1)$\times$10$^{-16}$ s$^{-1}$, and [S/H]$\sim$1.5$\times$10$^{-6}$. On the contrary, most of the positions in Orion are fitted with t=1~Myr and $\zeta_{H_2}$$\sim$ 10$^{-17}$ s$^{-1}$. Moreover, $\sim$40% of the positions in Orion are best fitted assuming the undepleted sulfur abundance, [S/H]$\sim$1.5$\times$10$^{-5}$. Our results suggest that sulfur depletion depends on the environment. While the abundances of sulfur-bearing species are consistent with undepleted sulfur in Orion, a depletion factor of $\sim$20 is required to explain those observed in Taurus and Perseus. We propose that differences in the grain charge distribution in the envelopes of the studied clouds might explain these variations. The shocks associated with past and ongoing star formation could also contribute to enhance [S/H] in Orion., Comment: 22 pages, 15 figures, Astronomy and Astrophysics, in press

Published
2022
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2. Gas phase Elemental abundances in Molecular cloudS (GEMS). IV. Observational results and statistical trends

Author

Rodríguez-Baras, M., Fuente, A., Riviére-Marichalar, P., Navarro-Almaida, D., Caselli, P., Gerin, M., Kramer, C., Roueff, E., Wakelam, V., Esplugues, G., García-Burillo, S., Gal, R. Le, Spezzano, S., Alonso-Albi, T., Bachiller, R., Cazaux, S., Commercon, B., Goicoechea, J. R., Loison, J. C., Treviño-Morales, S. P., Roncero, O., Jiménez-Serra, I., Laas, J., Hacar, A., Kirk, J., Lattanzi, V., Martín-Doménech, R., Muñoz-Caro, G., Pineda, J. E., Tercero, B., Ward-Thompson, D., Tafalla, M., Marcelino, N., Malinen, J., Friesen, R., and Giuliano, B. M.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

Gas phase Elemental abundances in Molecular CloudS (GEMS) is an IRAM 30m Large Program designed to estimate the S, C, N, and O depletions and gas ionization degree, X(e-), in a set of star-forming filaments of Taurus, Perseus and Orion. Our immediate goal is to build up a complete database of molecular abundances that can serve as an observational basis for estimating X(e-) and the C, O, N, and S depletions through chemical modeling. We observed and derived the abundances of 14 species (13CO, C18O, HCO+, H13CO+, HC18O+, HCN, H13CN, HNC, HCS+, CS, SO, 34SO, H2S, and OCS) in 244 positions, covering the AV 3 to 100 mag, n(H2) a few 10$^{3}$ to 10$^6$ cm$^{-3}$, and Tk 10 to 30 K ranges in these clouds, avoiding protostars, HII regions, and outflows. A statistical analysis is carried out to identify general trends between different species and with physical parameters. Relations between molecules reveal strong linear correlations which define three different families: (1) 13CO and C18O; (2) H13CO+, HC18O+, H13CN, and HNC; and (3) the S-bearing molecules. The abundances of the CO isotopologs increase with the gas kinetic temperature until TK 15 K. For higher temperatures, the abundance remains constant with a scatter of a factor of 3. The abundances of H13CO+, HC18O+, H13CN, and HNC are well correlated with each other, and all of them decrease with molecular hydrogen density, following the law n(H2)$^{-0.8\pm0.2}$. The abundances of S-bearing species also decrease with n(H2) at a rate of (S-bearing/H)gas n(H2)$^{-0.6\pm0.1}$. The abundances of molecules belonging to groups 2 and 3 do not present any clear trend with gas temperature. At scales of molecular clouds, the C18O abundance is the quantity that better correlates with the cloud mass. We discuss the utility of the 13CO/C18O, HCO+/H13CO+, and H13CO+/H13CN abundance ratios as chemical diagnostics of star formation in external galaxies., Comment: 28 pages, 22 figures. Accepted for publication in A&A

Published
2021
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3. Gas-phase Elemental abundances in Molecular cloudS (GEMS) III. Unlocking the CS chemistry: the CS+O reaction

Author

Bulut, N., Roncero, O., Aguado, A., Loison, J. -C., Navarro-Almaida, D., Wakelam, V., Fuente, A., Roueff, E., Gal, R. Le, Caselli, P., Hickson, M. Gerinm K. M., Spezzano, S., Riviere-Marichalar, P., Alonso-Albi, T., Bachiller, R., Jimenez-Serra, I., Kramer, C., Tercero, B., Rodriguez-Baras, M., Garcia-Burillo, S., Goicoechea, J. R., Treviño-Morales, S. P., Esplugues, G., Cazaux, S., Commercon, B., Laas, J., Kirk, J., Lattanzi, V., Martin-Domenech, R., Muñoz-Caro, G., Pineda, J., Ward-Thompson, D., Tafalla, M., Marcelino, N., Malinen, J., Friesen, R., Giuliano, B. M., Agundez, M., and Hacar, A.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

CS is among the most abundant gas-phase S-bearing molecules in cold dark molecular clouds. It is easily observable with several transitions in the millimeter wavelength range, and has been widely used as a tracer of the gas density in the interstellar medium in our Galaxy and external galaxies. Chemical models fail to account for the observed CS abundances when assuming the cosmic value for the elemental abundance of sulfur. The CS+O -> CO + S reaction has been proposed as a relevant CS destruction mechanism at low temperatures, and could explain the discrepancy between models and observations. Its reaction rate has been experimentally measured at temperatures of 150-400 K, but the extrapolation to lower temperatures is doubtful. Here we calculate the CS+O reaction rate at temperatures <150 K which are prevailing in the interstellar medium. We performed ab initio calculations to obtain the three lowest PES of the CS+O system. These PESs are used to study the reaction dynamics, using several methods to eventually calculate the CS+O thermal reaction rates. We compare the results of our theoretical calculations for 150-400 K with those obtained in the laboratory. Our detailed theoretical study on the CS+O reaction, which is in agreement with the experimental data obtained at 150-400 K, demonstrates the reliability of our approach. After a careful analysis at lower temperatures, we find that the rate constant at 10 K is negligible, which is consistent with the extrapolation of experimental data using the Arrhenius expression. We use the updated chemical network to model the sulfur chemistry in TMC1 based on molecular abundances determined from GEMS project observations. In our model, we take into account the expected decrease of the cosmic ray ionization rate along the cloud. The abundance of CS is still overestimated when assuming the cosmic value for the sulfur abundance., Comment: 11 pages, 10 figures, accepted in Astronomy & Astrophysics

Published
2020
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5. Gas phase Elemental abundances in Molecular cloudS (GEMS) I. The prototypical dark cloud TMC 1

Author

Fuente, A., Navarro, D., Caselli, P., Gerin, M., Kramer, C., Roueff, E., Alonso-Albi, T., Bachiller, R., Cazaux, S., Commercon, B., Friesen, R., García-Burillo, S., Giuliano, B. M., Goicoechea, J. R., Gratier, P., Hacar, A., Jiménez-Serra, I., Kirk, J., Lattanzi, V., Loison, J. C., Malinen, P. J., Marcelino, N., Martín-Doménech, R., Muñoz-Caro, G., Pineda, J., Tafalla, M., Tercero, B., Ward-Thompson, D., Treviño-Morales, S., Riviére-Marichalar, P., Roncero, O., Vidal, T., and Ballester, Maikel Y.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

GEMS is an IRAM 30m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud TMC 1. Extensive millimeter observations have been carried out with the IRAM 30m telescope (3mm and 2mm) and the 40m Yebes telescope (1.3cm and 7mm) to determine the fractional abundances of CO, HCO+, HCN, CS, SO, HCS+, and N2H+ in three cuts which intersect the dense filament at the well-known positions TMC 1-CP, TMC 1-NH3, and TMC 1-C, covering a visual extinction range from Av~3 to ~20mag. Two phases with differentiated chemistry can be distinguished: i) the translucent envelope with molecular hydrogen densities of (1-5)x10$^3$ cm$^{-3}$; and ii) the dense phase, located at Av>10mag, with molecular hydrogen densities >10$^4$ cm$^{-3}$. Observations and modeling show that the gas phase abundances of C and O progressively decrease along the C+/C/CO transition zone where C/H~8x10$^{-5}$ and C/O~0.8-1, until the beginning of the dense phase at Av~10 mag. This is consistent with the grain temperatures being below the CO evaporation temperature in this region. In the case of sulfur, a strong depletion should occur before the translucent phase where we estimate a S/H~(0.4 - 2.2) x10$^{-6}$, an abundance ~7-40 times lower than the solar value. A second strong depletion must be present during the formation of the thick icy mantles to achieve the values of S/H measured in the dense cold cores (S/H~8x10$^{-8}$). Based on our chemical modeling, we constrain the value of $\zeta_{\rm H_2}$ to ~(0.5 - 1.8) x10$^{-16}$ s$^{-1}$ in the translucent cloud., Comment: 26 pages, 20 figures, A&A in press

Published
2018
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6. Organic matter in Seyfert2 nuclei : comparison with our Galactic center lines of sight

Author

Dartois, E., Marco, O., Muñoz-Caro, G. M., Brooks, K., Deboffle, D., and d'Hendecourt, L.

Subjects
Astrophysics
Abstract

We present ESO - Very Large Telescope and ESA - Infrared Space Observatory 3 to 4 $\mu$m spectra of Seyfert 2 nuclei as compared to our galactic center lines of sight. The diffuse interstellar medium probed in both environments displays the characteristic 3.4 $\mu$m aliphatic CH stretch absorptions of refractory carbonaceous material. The profile of this absorption feature is similar in all sources, indicating the CH$_2$/CH$_3$ ratios of the carbon chains present in the refractory components of the grains are the same in Seyfert 2 inner regions. At longer wavelengths the circumstellar contamination of most of the galactic lines of sight precludes the identification of other absorption bands arising from the groups constitutive of the aliphatics seen at 3.4 $\mu$m. The clearer continuum produced by the Seyfert 2 nuclei represents promising lines of sight to constrain the existence or absence of strongly infrared active chemical groups such as the carbonyl one, important to understand the role of oxygen insertion in interstellar grains. The Spitzer Space Telescope spectrometer will soon allow one to investigate the importance of aliphatics on a much larger extragalactic sample., Comment: 10 pages. Accepted for publication on April 30th 2004 in Astronomy and Astrophysics

Published
2004
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7. Gas phase Elemental abundances in Molecular cloudS (GEMS): III. Unlocking the CS chemistry: the CS plus O reaction

Author

Bulut, N., Roncero, O., Aguado, A., Loison, J-C, Navarro-Almaida, D., Wakelam, V, Fuente, A., Roueff, E., Le Gal, R., Caselli, P., Gerin, M., Hickson, K. M., Spezzano, S., Riviere-Marichalar, P., Alonso-Albi, T., Bachiller, R., Jimenez-Serra, I, Kramer, C., Tercero, B., Rodriguez-Baras, M., Garcia-Burillo, S., Goicoechea, J. R., Trevino-Morales, S. P., Esplugues, G., Cazaux, S., Commercon, B., Laas, J., Kirk, J., Lattanzi, V, Martin-Domenech, R., Munoz-Caro, G., Pineda, J., Ward-Thompson, D., Tafalla, M., Marcelino, N., Malinen, J., Friesen, R., Giuliano, B. M., Agundez, M., Hacar, A., Bulut, N., Roncero, O., Aguado, A., Loison, J-C, Navarro-Almaida, D., Wakelam, V, Fuente, A., Roueff, E., Le Gal, R., Caselli, P., Gerin, M., Hickson, K. M., Spezzano, S., Riviere-Marichalar, P., Alonso-Albi, T., Bachiller, R., Jimenez-Serra, I, Kramer, C., Tercero, B., Rodriguez-Baras, M., Garcia-Burillo, S., Goicoechea, J. R., Trevino-Morales, S. P., Esplugues, G., Cazaux, S., Commercon, B., Laas, J., Kirk, J., Lattanzi, V, Martin-Domenech, R., Munoz-Caro, G., Pineda, J., Ward-Thompson, D., Tafalla, M., Marcelino, N., Malinen, J., Friesen, R., Giuliano, B. M., Agundez, M., and Hacar, A.

Abstract

Context. Carbon monosulphide (CS) is among the most abundant gas-phase S-bearing molecules in cold dark molecular clouds. It is easily observable with several transitions in the millimeter wavelength range, and has been widely used as a tracer of the gas density in the interstellar medium in our Galaxy and external galaxies. However, chemical models fail to account for the observed CS abundances when assuming the cosmic value for the elemental abundance of sulfur. Aims. The CS+O -> CO + S reaction has been proposed as a relevant CS destruction mechanism at low temperatures, and could explain the discrepancy between models and observations. Its reaction rate has been experimentally measured at temperatures of 150-400 K, but the extrapolation to lower temperatures is doubtful. Our goal is to calculate the CS+O reaction rate at temperatures <150 K which are prevailing in the interstellar medium. Methods. We performed ab initio calculations to obtain the three lowest potential energy surfaces (PES) of the CS+O system. These PESs are used to study the reaction dynamics, using several methods (classical, quantum, and semiclassical) to eventually calculate the CS + O thermal reaction rates. In order to check the accuracy of our calculations, we compare the results of our theoretical calculations for T similar to 150-400 K with those obtained in the laboratory. Results. Our detailed theoretical study on the CS+O reaction, which is in agreement with the experimental data obtained at 150-400 K, demonstrates the reliability of our approach. After a careful analysis at lower temperatures, we find that the rate constant at 10 K is negligible, below 10(-15) cm(3) s(-1), which is consistent with the extrapolation of experimental data using the Arrhenius expression. Conclusions. We use the updated chemical network to model the sulfur chemistry in Taurus Molecular Cloud 1 (TMC 1) based on molecular abundances determined from Gas phase Elemental abundances in Molecular CloudS (GEMS)

Published
2021

8. Amino acids from ultraviolet irradiation of interstellar ice analogues

Author

Munoz Caro, G. M., Meierhenrich, U. J., Schutte, W. A., Barbier, B., Arcones Segovia, A., Rosenbauer, H., Thiemann, W. H.-P., Brack, A., and Greenberg, J. M.

Subjects
Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): G. M. Muñoz Caro [1]; U. J. Meierhenrich (corresponding author) [2, 3]; W. A. Schutte [1]; B. Barbier [2]; A. Arcones Segovia [1]; H. Rosenbauer [4]; W. H.-P. Thiemann [...]

Published
2002
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9. Gas phase Elemental abundances in Molecular cloudS (GEMS) I. The prototypical dark cloud TMC 1

Author

Fuente, A., Navarro, D. G., Caselli, P., Gerin, M., Kramer, C., Roueff, E., Alonso-Albi, T., Bachiller, R., Cazaux, S., Commercon, B., Friesen, R., Garcia-Burillo, S., Giuliano, B. M., Goicoechea, J. R., Gratier, P., Hacar, A., Jimenez-Serra, I, Kirk, J., Lattanzi, V, Loison, J. C., Malinen, J., Marcelino, N., Martin-Domenech, R., Munoz-Caro, G., Pineda, J., Tafalla, M., Tercero, B., Ward-Thompson, D., Trevino-Morales, S. P., Riviere-Marichalar, P., Roncero, O., Vidal, T., Ballester, M. Y., Fuente, A., Navarro, D. G., Caselli, P., Gerin, M., Kramer, C., Roueff, E., Alonso-Albi, T., Bachiller, R., Cazaux, S., Commercon, B., Friesen, R., Garcia-Burillo, S., Giuliano, B. M., Goicoechea, J. R., Gratier, P., Hacar, A., Jimenez-Serra, I, Kirk, J., Lattanzi, V, Loison, J. C., Malinen, J., Marcelino, N., Martin-Domenech, R., Munoz-Caro, G., Pineda, J., Tafalla, M., Tercero, B., Ward-Thompson, D., Trevino-Morales, S. P., Riviere-Marichalar, P., Roncero, O., Vidal, T., and Ballester, M. Y.

Abstract

GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud Taurus molecular cloud (TMC) 1. Extensive millimeter observations have been carried out with the IRAM 30 m telescope (3 and 2mm) and the 40 m Yebes telescope (1.3 cm and 7 mm) to determine the fractional abundances of CO, HCO+, HCN, CS, SO, HCS+, and N2H+ in three cuts which intersect the dense filament at the well-known positions TMC 1-CP, TMC 1-NH3, and TMC 1-C, covering a visual extinction range from A(v) similar to 3 to similar to 20 mag. Two phases with differentiated chemistry can be distinguished: (i) the translucent envelope with molecular hydrogen densities of 1-5 x 10(3) cm(-3); and (ii) the dense phase, located at A(v) > 10 mag, with molecular hydrogen densities >10(4) cm(-3). Observations and modeling show that the gas phase abundances of C and O progressively decrease along the C+/C/CO transition zone (A(v) similar to 3 mag) where C/H similar to 8 x 10(-5) and C/O similar to 0.8-1, until the beginning of the dense phase at A(v) similar to 10 mag. This is consistent with the grain temperatures being below the CO evaporation temperature in this region. In the case of sulfur, a strong depletion should occur before the translucent phase where we estimate an S/H similar to (0.4-2.2) x 10(-6), an abundance similar to 7-40 times lower than the solar value. A second strong depletion must be present during the formation of the thick icy mantles to achieve the values of S/H measured in the dense cold cores (S/H similar to 8 x 10(-8)). Based on our chemical modeling, we constrain the value of zeta(H2) to similar to(0.5-1.8) x 10(-16) s(-1) in the translucent cloud.

Published
2019

10. Organic Compounds on the Nucleus of Comet 67/Churyumov-Gerasimenko as Revealed by COSAC Mass Spectrometry

Author

Goesmann , Fred, Rosenbauer , Helmut, Bredehoeft , Jan Hendrik, Cabane , Michel, Ehrenfreund , Pascale, Gauthier , Thomas, Giri , Chaitanya, Krueger , Harald, Le Roy , Léna, Mc Dermott , Alexandra, McKenna Lawlor , Susan, Meierhenrich , U., Munoz Caro , G., Raulin , François, Roll , R., Steele , A., Steininger , H., Sternberg , R., Szopa , Cyril, Thiemann , W., Ulamec , S., Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Institute for Applied and Physical Chemistry [Bremen] (IAPC), University of Bremen, 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), Leiden Observatory [Leiden], Universiteit Leiden, Space Policy Institute [Washington], The George Washington University (GW), NASA Goddard Space Flight Center (GSFC), Institut de Chimie de Nice (ICN), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Center for Space and Habitability (CSH), University of Bern, University of Houston [Clear Lake], Space Technology Ireland Limited, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), 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), Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science, German Aerospace Center (DLR), USRA Houston, Max Planck Institute for Solar System Research (MPS), Universiteit Leiden [Leiden], Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Carnegie Institution for Science [Washington], Cardon, Catherine, Max Planck Institute for Solar System Research ( MPS ), Institute for Applied and Physical Chemistry [Bremen] ( IAPC ), IMPEC - 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 ), George Washington University ( GW ), NASA Goddard Space Flight Center ( GSFC ), Institut de Chimie de Nice ( ICN ), Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Center for Space and Habitability ( CSH ), University of Houston-Clear Lake, Centro de Astrobiologia [Madrid] ( CAB ), Instituto Nacional de Técnica Aeroespacial ( INTA ) -Consejo Superior de Investigaciones Científicas [Spain] ( CSIC ), Laboratoire inter-universitaire des systèmes atmosphèriques ( LISA ), 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 ), German Aerospace Center ( DLR ), George Washington University (GW), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), 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
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [ SDU.ASTR.EP ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; The evolved gas analyzer COmetary SAmplingand Composition experiment (COSAC) aboardthe Philae Lander of ESA’s Rosetta mission was designedto make unique in situ chemical analyses ofnucleus material from comet 67P/Churyumov-Gerasimenko, with an emphasis on organic molecules.Twenty-five minutes after Philae’s initial touchdown,the COSAC mass spectrometer took a spectrum insniffing mode, which displayed an interesting suite oforganic compounds. The sampled material is likely tohave originated from the dust cloud produced by Philae’sfirst contact with the ground. Analysis of themass spectrum shows 16 compounds, among them sixdistinct organic homologous series: alcohols, carbonyls,amines, nitriles, amides and isocyanates. Nearlyall the molecules inferred from our data are potentialprecursors, products, adducts or by-products of eachother that can be formed either by surface reactions orby thermal and/or radiation processing of icy surfaces.A relatively abundant nitrogen source, such as NH3, isrequired to form the suite of N-bearing species. Severalorganic compounds have not been identified in cometsbefore or only upper limits have been derived. Overallthe identified compounds provide indications of severalpossible links between interstellar chemistry, cometaryorganic chemistry and terrestrial prebiotic chemistry.These unique COSAC measurements from a cometarysurface provide an unprecedented glimpse intothe early origins of our solar system, 4.6 billion yearsago.

Published
2015

11. Rosetta - les investigations de Philae-COSAC sur la chiralité de molécules cométaire

Author

Meierhenrich, U., Goesmann, F., Rosenbauer, H., Bredehöft, J., Cabane, M., Ehrenfreund, P., Gautier, T., Giri, C., Krüger, H., Le Roy, J., MacDermott, A. J., McKenna-Lawlor, S., Munoz-Caro, G., Raulin, F., Roll, R., Steele, A., Steininger, H., Sternberg, R., Szopa, C., Thiemann, W., and Ulamec, S.

Subjects
COSAC, Rosetta, Philae
Published
2015

13. An overview of the measurements made by the COSAC instrument at comet 67/P Churyumov-Gerasimenko

Author

Goesmann, F., Bredehöft, J, Cabane, M., Ehrenfreund, P., Gautier, T., Giri, C., Krüger, H., McKenna-Lawlor, S., Meierhenrich, U., Munoz-Caro, G., Raulin, F., Steele, A., Steininger, H., Sternberg, R., Szopa, C., Thiemann, W., and Ulamec, S.

Subjects
Nutzerzentrum für Weltraumexperimente (MUSC), COSAC instrument
Abstract

In this paper data recorded by the Cometary Sampling and Composition experiment (COSAC), a pyrolysis - gas-chromatograph - mass-spectrometer (pyr GC-MS) aboard Philae are presented. After landing in a somewhat non-nominal way on the cometary nucleus of 67/P, Philae carried out its First Science Sequence. As part of these activities COSAC acquired seven mass-spectra in sniffing mode, the first while still flying, the other at the final landing site. In addition, since drilling of a soil sample was attempted at the final site, a combined GC-MS measurement was performed on the sample transferred to COSAC. In the MS measurement made after the first touch- down a wide range of mass peaks was observed. These are ascribed to a variety of organic compounds, quite a few of them oxygen and nitrogen bearing species. However, no sulfur compounds were detected. The following six MS sniffings showed peaks of decreasing signal intensity mostly, but not completely, following the temperature drop pertaining aboard Philae. The results of the GC-MS measurement were, if at all, only marginally different from an empty run performed by COSAC in April 2014 when Rosetta was still far from the comet. The implications of this result namely: (1) was a sample delivered at all? (2) what do the small signals mean?) will each be discussed.

Published
2015

14. The sulfur depletion problem: upper limits on the H2S2, HS2 center dot, and S-2 gas-phase abundances toward the low-mass warm core IRAS 16293-2422

Author

Martin-Domenech, R., Jimenez-Serra, I., Munoz Caro, G. M., Mueller, H. S. P., Occhiogrosso, A., Testi, L., Woods, P. M., Viti, S., Martin-Domenech, R., Jimenez-Serra, I., Munoz Caro, G. M., Mueller, H. S. P., Occhiogrosso, A., Testi, L., Woods, P. M., and Viti, S.

Abstract

Context. A fraction of the missing sulfur in dense clouds and circumstellar regions could be in the form of three species not yet detected in the interstellarmedium: H2S2, HS2 center dot, and S-2 according to experimental simulations performed under astrophysically relevant conditions. These S-S bonded molecules can be formed by the energetic processing of H2S-bearing ice mantles on dust grains, and subsequently desorb to the gas phase. Aims. The detection of these species could partially solve the sulfur depletion problem, and would help to improve our knowledge of the poorly known chemistry of sulfur in the interstellar medium. To this purpose we calculated the frequencies and expected intensities of the rotational transitions not previously reported, and performed dedicated ground-based observations toward the low-mass warm core IRAS 16293-2422, a region with one of the highest measured gas-phase H2S abundances. Methods. Observations in the submillimeter regime were obtained with the APEX 12 m telescope during 15 h of observation. A total of similar to 16 GHz were covered in a range of about 100 GHz, targeting a wide selection of the predicted rotational transitions of the three molecules. Results. The 1 sigma noise rms values were extracted in the spectral regions where the targeted species should have been detected. These values were a factor of 2-7 lower than those reached by previous observations toward the same source, and allowed us to estimate a 1 sigma upper limit to their molecular abundances of <= 8.1 x 10(-9), <= 1.1 x 10(-8), and <= 2.9 x 10(-7) relative to H-2, for H2S2, HS2 center dot, and S-2, respectively. Conclusions. The upper limit abundances of the three molecules containing the S-2 unit are up to two orders of magnitude lower than the H2S abundance in the source, and one order of magnitude lower than the expected abundances from the experimental simulations using ice analogs. Subsequent gas-phase chemistry after desorption could lower the abu

Published
2016

15. Martian fluvial conglomerates at gale crater

Author

Williams, R. M. E., Grotzinger, J. P., Dietrich, W. E., Gupta, S., Sumner, D. Y., Wiens, R. C., Mangold, N., Malin, M. C., Edgett, K. S., Maurice, S., Forni, O., Gasnault, O., Ollila, A., Newsom, H. E., Dromart, G., Palucis, M. C., Yingst, R. A., Anderson, R. B., Herkenhoff, K. E., Le Mouelic, S., Goetz, W., Madsen, M. B., Koefoed, A., Jensen, J. K., Bridges, J. C., Schwenzer, S. P., Lewis, K. W., Stack, K. M., Rubin, D., Kah, L. C., Bell, J. F., Farmer, J. D., Sullivan, R., Van Beek, T., Blaney, D. L., Pariser, O., Deen, R. G., Kemppinen, O., Bridges, N., Johnson, J. R., Minitti, M., Cremers, D., Edgar, L., Godber, A., Wadhwa, M., Wellington, D., McEwan, I., Newman, C., Richardson, M., Charpentier, A., Peret, L., King, P., Blank, J., Weigle, G., Schmidt, M., Li, S., Milliken, R., Robertson, K., Sun, V., Baker, M., Edwards, C., Ehlmann, B., Farley, K., Griffes, J., Miller, H., Newcombe, M., Pilorget, C., Rice, M., Siebach, K., Stolper, E., Brunet, C., Hipkin, V., Leveille, R., Marchand, G., Sobron Sanchez, P., Favot, L., Cody, G., Steele, A., Fluckiger, L., Lees, D., Nefian, A., Martin, M., Gailhanou, M., Westall, F., Israel, G., Agard, C., Baroukh, J., Donny, C., Gaboriaud, A., Guillemot, P., Lafaille, V., Lorigny, E., Paillet, A., Perez, R., Saccoccio, M., Yana, C., Aparicio, C. A., Caride Rodriguez, J., Carrasco Blazquez, I., Gomez Gomez, F., Elvira, J. G., Hettrich, S., Lepinette Malvitte, A., Marin Jimenez, M., Frias, J. M., Soler, J. M., Torres, F. J. M., Molina Jurado, A., Sotomayor, L. M., Munoz Caro, G., Navarro Lopez, S., Gonzalez, V. P., Garcia, J. P., Rodriguez Manfredi, J. A., Planello, J. J. R., Alejandra Sans Fuentes, S., Sebastian Martinez, E., Torres Redondo, J., O'Callaghan, R. U., Zorzano Mier, M.-P., Chipera, S., Lacour, J.-L., Mauchien, P., Sirven, J.-B., Manning, H., Fairen, A., Hayes, A., Joseph, J., Squyres, S., Thomas, P., Dupont, A., Lundberg, A., Melikechi, N., Mezzacappa, A., DeMarines, J., Grinspoon, D., Reitz, G., Prats, B., Atlaskin, E., Genzer, M., Harri, A.-M., Haukka, H., Kahanpaa, H., Kauhanen, J., Paton, M., Polkko, J., Schmidt, W., Siili, T., Fabre, C., Wray, J., Wilhelm, M. B., Poitrasson, F., Patel, K., Gorevan, S., Indyk, S., Paulsen, G., Bish, D., Schieber, J., Gondet, B., Langevin, Y., Geffroy, C., Baratoux, D., Berger, G., Cros, A., Uston, C. d., Lasue, J., Lee, Q.-M., Meslin, P.-Y., Pallier, E., Parot, Y., Pinet, P., Schroder, S., Toplis, M., Lewin, E., Brunner, W., Heydari, E., Achilles, C., Oehler, D., Sutter, B., Cabane, M., Coscia, D., Szopa, C., Robert, F., Sautter, V., Nachon, M., Buch, A., Stalport, F., Coll, P., Francois, P., Raulin, F., Teinturier, S., Cameron, J., Clegg, S., Cousin, A., DeLapp, D., Dingler, R., Jackson, R. S., Johnstone, S., Lanza, N., Little, C., Nelson, T., Williams, R. B., Jones, A., Kirkland, L., Treiman, A., Baker, B., Cantor, B., Caplinger, M., Davis, S., Duston, B., Fay, D., Hardgrove, C., Harker, D., Herrera, P., Jensen, E., Kennedy, M. R., Krezoski, G., Krysak, D., Lipkaman, L., McCartney, E., McNair, S., Nixon, B., Posiolova, L., Ravine, M., Salamon, A., Saper, L., Stoiber, K., Supulver, K., Van Beek, J., Zimdar, R., French, K. L., Iagnemma, K., Miller, K., Summons, R., Goesmann, F., Hviid, S., Johnson, M., Lefavor, M., Lyness, E., Breves, E., Dyar, M. D., Fassett, C., Blake, D. F., Bristow, T., DesMarais, D., Edwards, L., Haberle, R., Hoehler, T., Hollingsworth, J., Kahre, M., Keely, L., McKay, C., Bleacher, L., Brinckerhoff, W., Choi, D., Conrad, P., Dworkin, J. P., Eigenbrode, J., Floyd, M., Freissinet, C., Garvin, J., Glavin, D., Harpold, D., Mahaffy, P., Martin, D. K., McAdam, A., Pavlov, A., Raaen, E., Smith, M. D., Stern, J., Tan, F., Trainer, M., Meyer, M., Posner, A., Voytek, M., Anderson, R. C., Aubrey, A., Beegle, L. W., Behar, A., Brinza, D., Calef, F., Christensen, L., Crisp, J. A., DeFlores, L., Feldman, J., Feldman, S., Flesch, G., Hurowitz, J., Jun, I., Keymeulen, D., Maki, J., Mischna, M., Morookian, J. M., Parker, T., Pavri, B., Schoppers, M., Sengstacken, A., Simmonds, J. J., Spanovich, N., de la Torre Juarez, M., Vasavada, A. R., Webster, C. R., Yen, A., Archer, P. D., Cucinotta, F., Jones, J. H., Ming, D., Morris, R. V., Niles, P., Rampe, E., Nolan, T., Fisk, M., Radziemski, L., Barraclough, B., Bender, S., Berman, D., Dobrea, E. N., Tokar, R., Vaniman, D., Leshin, L., Cleghorn, T., Huntress, W., Manhes, G., Hudgins, J., Olson, T., Stewart, N., Sarrazin, P., Grant, J., Vicenzi, E., Wilson, S. A., Bullock, M., Ehresmann, B., Hamilton, V., Hassler, D., Peterson, J., Rafkin, S., Zeitlin, C., Fedosov, F., Golovin, D., Karpushkina, N., Kozyrev, A., Litvak, M., Malakhov, A., Mitrofanov, I., Mokrousov, M., Nikiforov, S., Prokhorov, V., Sanin, A., Tretyakov, V., Varenikov, A., Vostrukhin, A., Kuzmin, R., Clark, B., Wolff, M., McLennan, S., Botta, O., Drake, D., Bean, K., Lemmon, M., Lee, E. M., Sucharski, R., Hernandez, M. A. d. P., Blanco Avalos, J. J., Ramos, M., Kim, M.-H., Malespin, C., Plante, I., Muller, J.-P., Gonzalez, R. N., Ewing, R., Boynton, W., Downs, R., Fitzgibbon, M., Harshman, K., Morrison, S., Kortmann, O., Williams, A., Lugmair, G., Wilson, M. A., Jakosky, B., Zunic, T. B., Frydenvang, J., Kinch, K., Stipp, S. L. S., Boyd, N., Campbell, J. L., Gellert, R., Perrett, G., Pradler, I., VanBommel, S., Jacob, S., Owen, T., Rowland, S., Savijarvi, H., Boehm, E., Bottcher, S., Burmeister, S., Guo, J., Kohler, J., Garcia, C. M., Mellin, R. M., Schweingruber, R. W., McConnochie, T., Benna, M., Franz, H., Bower, H., Brunner, A., Blau, H., Boucher, T., Carmosino, M., Atreya, S., Elliott, H., Halleaux, D., Renno, N., Wong, M., Pepin, R., Elliott, B., Spray, J., Thompson, L., Gordon, S., Williams, J., Vasconcelos, P., Bentz, J., Nealson, K., Popa, R., Moersch, J., Tate, C., Day, M., Kocurek, G., Hallet, B., Sletten, R., Francis, R., McCullough, E., Cloutis, E., ten Kate, I. L., Arvidson, R., Fraeman, A., Scholes, D., Slavney, S., Stein, T., Ward, J., Berger, J., Moores, J. E., NWO-NSO: The role of perchlorates in the preservation of organic compounds on Mars, Petrology, GeoRessources, and 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)

Subjects
MSL Mars Gale Crater Fluvial Activity, Martian, Multidisciplinary, 010504 meteorology & atmospheric sciences, Outcrop, Curiosity rover, Geochemistry, Mars, Sediment, Fluvial, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mars Exploration Program, 01 natural sciences, Abrasion (geology), martian fluvial conglomerates, 13. Climate action, Rocknest, 0103 physical sciences, MSL, Sedimentary rock, 010303 astronomy & astrophysics, Geology, 0105 earth and related environmental sciences
Abstract

Going to Mars The Mars Science Laboratory spacecraft containing the Curiosity rover, was launched from Earth in November 2011 and arrived at Gale crater on Mars in August 2012. Zeitlin et al. (p. 1080 ) report measurements of the energetic particle radiation environment inside the spacecraft during its cruise to Mars, confirming the hazard likely to be posed by this radiation to astronauts on a future potential trip to Mars. Williams et al. (p. 1068 , see the Perspective by Jerolmack ) report the detection of sedimentary conglomerates (pebbles mixed with sand and turned to rock) at Gale crater. The rounding of the rocks suggests abrasion of the pebbles as they were transported by flowing water several kilometers or more from their source.

Published
2013
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16. Curiosity at Gale Crater, Mars: Characterization and analysis of the rocknest sand shadow

Author

Blake, D. F., Morris, R. V., Kocurek, G., Morrison, S. M., Downs, R. T., Bish, D., Ming, D. W., Edgett, K. S., Rubin, D., Goetz, W., Madsen, M. B., Sullivan, R., Gellert, R., Campbell, I., Treiman, A. H., McLennan, S. M., Yen, A. S., Grotzinger, J., Vaniman, D. T., Chipera, S. J., Achilles, C. N., Rampe, E. B., Sumner, D., Meslin, P.- Y., Maurice, S., Forni, O., Gasnault, O., Fisk, M., Schmidt, M., Mahaffy, P., Leshin, L. A., Glavin, D., Steele, A., Freissinet, C., Navarro-Gonzalez, R., Yingst, R. A., Kah, L. C., Bridges, N., Lewis, K. W., Bristow, T. F., Farmer, J. D., Crisp, J. A., Stolper, E. M., Des Marais, D. J., Sarrazin, P., Agard, C., Alves Verdasca, J. A., Anderson, R., Archer, D., Armiens-Aparicio, C., Arvidson, R., Atlaskin, E., Atreya, S., Aubrey, A., Baker, B., Baker, M., Balic-Zunic, T., Baratoux, D., Baroukh, J., Barraclough, B., Bean, K., Beegle, L., Behar, A., Bell, J., Bender, S., Benna, M., Bentz, J., Berger, G., Berger, J., Berman, D., Blanco Avalos, J. J., Blaney, D., Blank, J., Blau, H., Bleacher, L., Boehm, E., Botta, O., Bottcher, S., Boucher, T., Bower, H., Boyd, N., Boynton, B., Breves, E., Bridges, J., Brinckerhoff, W., Brinza, D., Brunet, C., Brunner, A., Brunner, W., Buch, A., Bullock, M., Burmeister, S., Cabane, M., Calef, F., Cameron, J., Cantor, B., Caplinger, M., Rodriguez, J. C., Carmosino, M., Blazquez, I. C., Charpentier, A., Choi, D., Clark, B., Clegg, S., Cleghorn, T., Cloutis, E., Cody, G., Coll, P., Conrad, P., Coscia, D., Cousin, A., Cremers, D., Cros, A., Cucinotta, F., d'Uston, C., Davis, S., Day, M., Juarez, M. d. l. T., DeFlores, L., DeLapp, D., DeMarines, J., Dietrich, W., Dingler, R., Donny, C., Drake, D., Dromart, G., Dupont, A., Duston, B., Dworkin, J., Dyar, M. D., Edgar, L., Edwards, C., Edwards, L., Ehlmann, B., Ehresmann, B., Eigenbrode, J., Elliott, B., Elliott, H., Ewing, R., Fabre, C., Fairen, A., Farley, K., Fassett, C., Favot, L., Fay, D., Fedosov, F., Feldman, J., Feldman, S., Fitzgibbon, M., Flesch, G., Floyd, M., Fluckiger, L., Fraeman, A., Francis, R., Francois, P., Franz, H., French, K. L., Frydenvang, J., Gaboriaud, A., Gailhanou, M., Garvin, J., Geffroy, C., Genzer, M., Godber, A., Goesmann, F., Golovin, D., Gomez, F. G., Gomez-Elvira, J., Gondet, B., Gordon, S., Gorevan, S., Grant, J., Griffes, J., Grinspoon, D., Guillemot, P., Guo, J., Gupta, S., Guzewich, S., Haberle, R., Halleaux, D., Hallet, B., Hamilton, V., Hardgrove, C., Harker, D., Harpold, D., Harri, A.-M., Harshman, K., Hassler, D., Haukka, H., Hayes, A., Herkenhoff, K., Herrera, P., Hettrich, S., Heydari, E., Hipkin, V., Hoehler, T., Hollingsworth, J., Hudgins, J., Huntress, W., Hurowitz, J., Hviid, S., Iagnemma, K., Indyk, S., Israel, G., Jackson, R., Jacob, S., Jakosky, B., Jensen, E., Jensen, J. K., Johnson, J., Johnson, M., Johnstone, S., Jones, A., Jones, J., Joseph, J., Jun, I., Kahanpaa, H., Kahre, M., Karpushkina, N., Kasprzak, W., Kauhanen, J., Keely, L., Kemppinen, O., Keymeulen, D., Kim, M.-H., Kinch, K., King, P., Kirkland, L., Koefoed, A., Kohler, J., Kortmann, O., Kozyrev, A., Krezoski, J., Krysak, D., Kuzmin, R., Lacour, J. L., Lafaille, V., Langevin, Y., Lanza, N., Lasue, J., Le Mouelic, S., Lee, E. M., Lee, Q.-M., Lees, D., Lefavor, M., Lemmon, M., Lepinette Malvitte, A., Leveille, R., Lewin-Carpintier, E., Li, S., Lipkaman, L., Little, C., Litvak, M., Lorigny, E., Lugmair, G., Lundberg, A., Lyness, E., Maki, J., Malakhov, A., Malespin, C., Malin, M., Mangold, N., Manning, H., Marchand, G., Marin Jimenez, M., Martin Garcia, C., Martin, D., Martin, M., Martinez-Frias, J., Martin-Soler, J., Martin-Torres, F. J., Mauchien, P., McAdam, A., McCartney, E., McConnochie, T., McCullough, E., McEwan, I., McKay, C., McNair, S., Melikechi, N., Meyer, M., Mezzacappa, A., Miller, H., Miller, K., Milliken, R., Minitti, M., Mischna, M., Mitrofanov, I., Moersch, J., Mokrousov, M., Molina Jurado, A., Moores, J., Mora-Sotomayor, L., Morookian, J. M., Mueller-Mellin, R., Muller, J.-P., Munoz Caro, G., Nachon, M., Navarro Lopez, S., Nealson, K., Nefian, A., Nelson, T., Newcombe, M., Newman, C., Newsom, H., Nikiforov, S., Niles, P., Nixon, B., Dobrea, E. N., Nolan, T., Oehler, D., Ollila, A., Olson, T., Owen, T., Pablo, H., Paillet, A., Pallier, E., Palucis, M., Parker, T., Parot, Y., Patel, K., Paton, M., Paulsen, G., Pavlov, A., Pavri, B., Peinado-Gonzalez, V., Pepin, R., Peret, L., Perez, R., Perrett, G., Peterson, J., Pilorget, C., Pinet, P., Pla-Garcia, J., Plante, I., Poitrasson, F., Polkko, J., Popa, R., Posiolova, L., Pradler, I., Prats, B., Prokhorov, V., Purdy, S. W., Raaen, E., Radziemski, L., Rafkin, S., Ramos, M., Raulin, F., Ravine, M., Reitz, G., Renno, N., Rice, M., Richardson, M., Robert, F., Rodriguez Manfredi, J. A., Romeral-Planello, J. J., Rowland, S., Saccoccio, M., Salamon, A., Sandoval, J., Sanin, A., Sans Fuentes, S. A., Saper, L., Sautter, V., Savijarvi, H., Schieber, J., Schmidt, W., Scholes, D., Schoppers, M., Schroder, S., Sebastian Martinez, E., Sengstacken, A., Shterts, R., Siebach, K., Siili, T., Simmonds, J., Sirven, J.-B., Slavney, S., Sletten, R., Smith, M., Sobron Sanchez, P., Spanovich, N., Spray, J., Squyres, S., Stack, K., Stalport, F., Stein, T., Stern, J., Stewart, N., Stipp, S. L. S., Stoiber, K., Sucharski, B., Summons, R., Sun, V., Supulver, K., Sutter, B., Szopa, C., Tate, C., Teinturier, S., ten Kate, I. L., Thomas, P., Thompson, L., Tokar, R., Toplis, M., Torres Redondo, J., Trainer, M., Tretyakov, V., Urqui-O'Callaghan, R., Van Beek, J., Van Beek, T., VanBommel, S., Varenikov, A., Vasavada, A., Vasconcelos, P., Vicenzi, E., Vostrukhin, A., Voytek, M., Wadhwa, M., Ward, J., Webster, C., Weigle, E., Wellington, D., Westall, F., Wiens, R. C., Wilhelm, M. B., Williams, A., Williams, J., Williams, R., Williams, R. B., Wilson, M., Wimmer-Schweingruber, R., Wolff, M., Wong, M., Wray, J., Wu, M., Yana, C., Zeitlin, C., Zimdar, R., Zorzano Mier, M.-P., GeoRessources, 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), NASA Ames Research Center (ARC), NASA Johnson Space Center (JSC), NASA, Department of Geological Sciences [Austin], Jackson School of Geosciences (JSG), University of Texas at Austin [Austin]-University of Texas at Austin [Austin], Department of Geology [Tucson], University of Arizona, Department of Geological Sciences [Bloomington], Indiana University [Bloomington], Indiana University System-Indiana University System, Malin Space Science Systems (MSSS), NASA Goddard Space Flight Center (GSFC), NWO-NSO: The role of perchlorates in the preservation of organic compounds on Mars, and Petrology

Subjects
Basalt, Meridiani Planum, Multidisciplinary, 010504 meteorology & atmospheric sciences, Curiosity rover, Geochemistry, Mars, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mars Exploration Program, Exploration of Mars, 01 natural sciences, Astrobiology, Impact crater, 13. Climate action, MSL Mars Gale Crater Rocknest, Rocknest, 0103 physical sciences, Sample Analysis at Mars, Aeolian processes, MSL, Rocknest aeolian deposit, 010303 astronomy & astrophysics, Geology, 0105 earth and related environmental sciences
Abstract

The Rocknest aeolian deposit is similar to aeolian features analyzed by the Mars Exploration Rovers (MERs) Spirit and Opportunity. The fraction of sand

Published
2013
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19. Soft X-Ray Irradiation of Methanol Ice: Implication for H2CO Formation in Interstellar Regions

Author

S. Giarrusso, G. M. Muñoz Caro, Alfonso Collura, Marco Barbera, Cesare Cecchi-Pestellini, Angela Ciaravella, A. Jimenez Escobar, Ciaravella, A, Munoz Caro, G, Jimenez Escobar, A, Cecchi-Pestellini, C, Giarrusso, S, Barbera, M, and Collura, A

Subjects
Physics, Photodissociation, Formaldehyde, Astronomy and Astrophysics, Radiation, Photochemistry, Chemical reaction, Decomposition, chemistry.chemical_compound, ISM: molecules – methods: laboratory – X-rays: ISM, Settore FIS/05 - Astronomia E Astrofisica, chemistry, Space and Planetary Science, Molecule, Irradiation, Methanol, Atomic physics
Abstract

We performed 0.3 keV soft X-ray irradiation of a methanol ice at 8 K under ultra-high vacuum conditions. To the best of our knowledge, this is the first time that soft X-rays are used to study photolysis of ice analogs. Despite the low irradiation dose of 10{sup -6} photons molecule{sup -1}, the formation of formaldehyde has been observed. The results of our experiments suggest that X-rays may be a promising candidate to the formation of complex molecules in regions where UV radiation is severely inhibited.

Published
2010

20. Simulated cometary matter as a test for enantiomer separating chromatography for use on comet 46P/Wirtanen.

Author

Meierhenrich UJ, Thiemann WH, Munoz Caro GM, Schutte WA, and Greenberg JM

Subjects
Ammonia chemistry, Carbon Dioxide chemistry, Carbon Isotopes, Carbon Monoxide chemistry, Evaluation Studies as Topic, Evolution, Chemical, Exobiology, Extraterrestrial Environment, Hot Temperature, Methanol chemistry, Methenamine analysis, Spacecraft instrumentation, Stereoisomerism, Water chemistry, Gas Chromatography-Mass Spectrometry instrumentation, Ice analysis, Meteoroids, Methenamine chemical synthesis, Space Flight instrumentation
Abstract

The Cometary Sampling and Composition Experiment on board of European Space Agency's cornerstone mission ROSETTA is designed to identify organic molecules in cometary matter in situ by a combined pyrolysis gas chromatographic and mass spectrometric technique. Its capillary columns coated with chiral stationary phases received considerable attention, because they are designed for separations of non-complex enantiomers to allow the determination of enantiomeric ratios of cometary chiral organic compounds and consequently to provide information about the origin of molecular parity violation in biomolecules. To get gas chromatographic access to organic compounds on the comet, where macromolecules and complex organic polymers of low volatility are expected to make up the main organic ingredients, the combination of two injection techniques will be applied. The pyrolysis technique performed by heating cometary samples stepwise to defined temperatures in specific ovens resulting in thermochemolysis reactions of polymers and a chemical derivatization technique, in which the reagent dimethylformamide dimethylacetal assists pyrolysis derivatization reactions in producing methyl esters of polar monomers. The combination of the reagent assisted pyrolysis gas chromatographic technique with enantiomer separating chromatography was tested with laboratory-produced simulated cometary matter., (c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.)

Published
2001
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