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  • JOURNAL ARTICLE
    Court RW, Tan J, 2016,

    Insights into secondary reactions occurring during atmospheric ablation of micrometeoroids

    , METEORITICS & PLANETARY SCIENCE, Vol: 51, Pages: 1163-1183, ISSN: 1086-9379
  • JOURNAL ARTICLE
    Gordon PR, Sephton MA, 2016,

    Rapid habitability assessment of Mars samples by pyrolysis-FTIR

    , Planetary and Space Science, Vol: 121, Pages: 60-75, ISSN: 1873-5088

    Pyrolysis Fourier transform infrared spectroscopy (pyrolysis FTIR) is a potential sample selection method for Mars Sample Return missions. FTIR spectroscopy can be performed on solid and liquid samples but also on gases following preliminary thermal extraction, pyrolysis or gasification steps. The detection of hydrocarbon and non-hydrocarbon gases can reveal information on sample mineralogy and past habitability of the environment in which the sample was created. The absorption of IR radiation at specific wavenumbers by organic functional groups can indicate the presence and type of any organic matter present. Here we assess the utility of pyrolysis-FTIR to release water, carbon dioxide, sulphur dioxide and organic matter from Mars relevant materials to enable a rapid habitability assessment of target rocks for sample return. For our assessment a range of minerals were analysed by attenuated total reflectance FTIR. Subsequently, the mineral samples were subjected to single step pyrolysis and multi step pyrolysis and the products characterised by gas phase FTIR.Data from both single step and multi step pyrolysis-FTIR provide the ability to identify minerals that reflect habitable environments through their water and carbon dioxide responses. Multi step pyrolysis-FTIR can be used to gain more detailed information on the sources of the liberated water and carbon dioxide owing to the characteristic decomposition temperatures of different mineral phases. Habitation can be suggested when pyrolysis-FTIR indicates the presence of organic matter within the sample. Pyrolysis-FTIR, therefore, represents an effective method to assess whether Mars Sample Return target rocks represent habitable conditions and potential records of habitation and can play an important role in sample triage operations.

  • JOURNAL ARTICLE
    Montgomery W, Sephton MA, 2016,

    PRESSURE EFFECTS IN POLYCYCLIC AROMATIC NITROGENATED HETEROCYCLES (PANHs): DIAGNOSTIC QUALITIES AND COSMOBAROMETRY POTENTIAL

    , ASTROPHYSICAL JOURNAL, Vol: 819, ISSN: 0004-637X
  • JOURNAL ARTICLE
    Myrgorodska I, Meinert C, Martins Z, le Sergeant d'Hendecourt L, Meierhenrich UJet al., 2016,

    Quantitative enantioseparation of amino acids by comprehensive two-dimensional gas chromatography applied to non-terrestrial samples.

    , J Chromatogr A, Vol: 1433, Pages: 131-136

    This work presents an improved analytical procedure for the resolution and quantification of amino acid enantiomers by multidimensional gas chromatography. The procedure contains a derivatization step, by which amino acids were transformed into N(O,S)-ethoxycarbonylheptafluorobutyl esters. It was optimized for the resolution of non-proteinogenic amino acids in the matrix of complex non-terrestrial samples. The procedure has proven to be highly sensitive and shows a wide linearity range with 0.005-3 pmol detection limits for quantitative determinations. The developed procedure was tested on a sample of the Murchison meteorite, for which obtained chromatograms show excellent peak resolution, minimal co-elution and peak overlap. We conclude that comprehensive two dimensional chromatography, in combination with the optimized derivatization method is a highly suitable technique for the analysis of samples with very limited quantities and containing potentially prebiotic molecules, such as interstellar ice analogs and meteorites.

  • JOURNAL ARTICLE
    Najorka J, Lewis JMT, Spratt J, Sephton MAet al., 2016,

    Single-crystal X-ray diffraction study of synthetic sodium-hydronium jarosite

    , PHYSICS AND CHEMISTRY OF MINERALS, Vol: 43, Pages: 377-386, ISSN: 0342-1791
  • CONFERENCE PAPER
    Abubakar R, Muxworthy AR, Sephton M, Fraser A, Heslop D, Paterson G, Southern Pet al., 2015,

    Mapping Petroluem Migration Pathways Using Magnetics and Seismic Interpretations (poster)

    , AGU Fall 2015
  • JOURNAL ARTICLE
    Abubakar R, Muxworthy AR, Sephton MA, Southern P, Watson JS, Fraser AJ, Almeida TPet al., 2015,

    Formation of magnetic minerals at hydrocarbon-generation conditions

    , MARINE AND PETROLEUM GEOLOGY, Vol: 68, Pages: 509-519, ISSN: 0264-8172
  • JOURNAL ARTICLE
    Cottin H, Kotler JM, Bartik K, Cleaves HJ, Cockell CS, de Vera JPP, Ehrenfreund P, Leuko S, Ten Kate IL, Martins Z, Pascal R, Quinn R, Rettberg P, Westall Fet al., 2015,

    Astrobiology and the Possibility of Life on Earth and Elsewhere…

    , Space Science Reviews, ISSN: 0038-6308

    © 2015 Springer Science+Business Media DordrechtAstrobiology is an interdisciplinary scientific field not only focused on the search of extraterrestrial life, but also on deciphering the key environmental parameters that have enabled the emergence of life on Earth. Understanding these physical and chemical parameters is fundamental knowledge necessary not only for discovering life or signs of life on other planets, but also for understanding our own terrestrial environment. Therefore, astrobiology pushes us to combine different perspectives such as the conditions on the primitive Earth, the physicochemical limits of life, exploration of habitable environments in the Solar System, and the search for signatures of life in exoplanets. Chemists, biologists, geologists, planetologists and astrophysicists are contributing extensively to this interdisciplinary research field. From 2011 to 2014, the European Space Agency (ESA) had the initiative to gather a Topical Team of interdisciplinary scientists focused on astrobiology to review the profound transformations in the field that have occurred since the beginning of the new century. The present paper is an interdisciplinary review of current research in astrobiology, covering the major advances and main outlooks in the field. The following subjects will be reviewed and most recent discoveries will be highlighted: the new understanding of planetary system formation including the specificity of the Earth among the diversity of planets, the origin of water on Earth and its unique combined properties among solvents for the emergence of life, the idea that the Earth could have been habitable during the Hadean Era, the inventory of endogenous and exogenous sources of organic matter and new concepts about how chemistry could evolve towards biological molecules and biological systems. In addition, many new findings show the remarkable potential life has for adaptation and survival in extreme environments. All those results fr

  • JOURNAL ARTICLE
    Lewis JMT, Watson JS, Najorka J, Duy L, Sephton MAet al., 2015,

    Sulfate Minerals: A Problem for the Detection of Organic Compounds on Mars?

    , ASTROBIOLOGY, Vol: 15, Pages: 247-258, ISSN: 1531-1074
  • JOURNAL ARTICLE
    Luong D, Sephton MA, Watson JS, 2015,

    Subcritical water extraction of organic matter from sedimentary rocks

    , ANALYTICA CHIMICA ACTA, Vol: 879, Pages: 48-57, ISSN: 0003-2670
  • JOURNAL ARTICLE
    Martins Z, Modica P, Zanda B, D'Hendecourt LLSet al., 2015,

    The amino acid and hydrocarbon contents of the Paris meteorite: Insights into the most primitive CM chondrite

    , METEORITICS & PLANETARY SCIENCE, Vol: 50, Pages: 926-943, ISSN: 1086-9379
  • JOURNAL ARTICLE
    Matthewman R, Court RW, Crawford IA, Jones AP, Joy KH, Sephton MAet al., 2015,

    The Moon as a Recorder of Organic Evolution in the Early Solar System: A Lunar Regolith Analog Study

    , ASTROBIOLOGY, Vol: 15, Pages: 154-168, ISSN: 1531-1074
  • CONFERENCE PAPER
    Montgomery W, Sephton MA, Watson JS, Zeng Het al., 2015,

    The Effects of Minerals on Heavy-Oil and Bitumen Chemistry When Recovered by Steam-Assisted Methods

    , Publisher: SPE-SOC PETROLEUM ENGINEERS, CANADA, Pages: 15-17, ISSN: 0021-9487
  • JOURNAL ARTICLE
    Montgomery W, Sephton MA, Watson JS, Zeng H, Rees ACet al., 2015,

    Minimising hydrogen sulphide generation during steam assisted production of heavy oil

    , SCIENTIFIC REPORTS, Vol: 5, ISSN: 2045-2322
  • JOURNAL ARTICLE
    Mustafa KA, Sephton MA, Watson JS, Spathopoulos F, Krzywiec Pet al., 2015,

    Organic geochemical characteristics of black shales across the Ordovician-Silurian boundary in the Holy Cross Mountains, central Poland

    , MARINE AND PETROLEUM GEOLOGY, Vol: 66, Pages: 1042-1055, ISSN: 0264-8172
  • JOURNAL ARTICLE
    Myrgorodska I, Meinert C, Martins Z, Le Sergeant D'Hendecourt L, Meierhenrich UJet al., 2015,

    Molecular chirality in meteorites and interstellar ices, and the chirality experiment on board the ESA cometary rosetta mission

    , Angewandte Chemie - International Edition, Vol: 54, Pages: 1402-1412, ISSN: 1433-7851

    © 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.Life, as it is known to us, uses exclusively L-amino acid and D-sugar enantiomers for the molecular architecture of proteins and nucleic acids. This Minireview explores current models of the original symmetry-breaking influence that led to the exogenic delivery to Earth of prebiotic molecules with a slight enantiomeric excess. We provide a short overview of enantiomeric enhancements detected in bodies of extraterrestrial origin, such as meteorites, and interstellar ices simulated in the laboratory. Data are interpreted from different points of view, namely, photochirogenesis, parity violation in the weak nuclear interaction, and enantioenrichment through phase transitions. Photochemically induced enantiomeric imbalances are discussed more specifically in the topical context of the "chirality module" on board the cometary Rosetta spacecraft of the ESA. This device will perform the first enantioselective in situ analyses of samples taken from a cometary nucleus.

  • JOURNAL ARTICLE
    Sephton MA, Carter JN, 2015,

    The chances of detecting life on Mars

    , PLANETARY AND SPACE SCIENCE, Vol: 112, Pages: 15-22, ISSN: 0032-0633
  • JOURNAL ARTICLE
    Sephton MA, Jiao D, Engel MH, Looy CV, Visscher Het al., 2015,

    Terrestrial acidification during the end-Permian biosphere crisis?

    , GEOLOGY, Vol: 43, Pages: 159-162, ISSN: 0091-7613
  • JOURNAL ARTICLE
    Sephton MA, Watson JS, Meredith W, Love GD, Gilmour I, Snape CEet al., 2015,

    Multiple Cosmic Sources for Meteorite Macromolecules?

    , ASTROBIOLOGY, Vol: 15, Pages: 779-786, ISSN: 1531-1074
  • JOURNAL ARTICLE
    Torokova L, Watson J, Krcma F, Mazankova V, Mason NJ, Horvath G, Matejcik Set al., 2015,

    Gas Chromatography Analysis of Discharge Products in N2-CH4 Gas Mixture at Atmospheric Pressure: Study of Mimic Titan's Atmosphere

    , Contributions to Plasma Physics, Vol: 55, Pages: 470-480, ISSN: 0863-1042

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

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