Now showing items 1-20 of 31

    • Calibrations of phase abundance, composition, and particle size distribution for olivine-orthopyroxene mixtures from reflectance spectra 

      Cloutis, Edward A.; Gaffey, Michael J.; Jackowski, Timothy L.; Reed, Kevin L. (American Geophysical Union, 1986-10-10)
      Spectral reflectance measurements of characterized (phase abundance, particle size) mixtures of olivine and orthopyroxene were utilized to define the correlations between spectral and albedo parameters of such assemblages ...
    • Reflectance spectra of "featureless" materials and the surface mineralogies of M- and E-class asteroids 

      Cloutis, Edward A.; Gaffey, Michael J.; Smith, Dorian G.W.; St. J. Lambert, Richard (Journal of Geophysical Research, 1990-01-10)
      The 0.3- to 2.6-μm reflectance spectra of meteoritic enstatite (nearly pure MgSiO3), iron meteorite metal, magnetite and amorphous carbon, and various mixtures of these materials with mafic silicates have been measured in ...
    • Metal-silicate mixtures: Spectral properties and applications to asteroid taxonomy. 

      Cloutis, Edward A.; Gaffey, Michael J.; Smith, Dorian G. W.; St. J. Lambert, Richard (Journal of Geophysical Research, 1990-06-10)
      The reflectance spectra of combinations of olivine, orthopyroxene, and iron meteorite metal show systematic variations in spectral properties which can be used to constrain many of the physical and chemical properties of ...
    • Pyroxene spectroscopy revisited: Spectral-compositional correlations and relationship to geothermometry. 

      Cloutis, Edward A.; Gaffey, Michael J. (Journal of Geophysical Research, 1991-12-25)
      Pyroxene reflectance and transmittance spectra have been examined in a search for systematic relationships between spectral features and compositional variations and to assess the applicability of reflectance spectroscopy ...
    • Manganese-rich olivines: Identification from spectral reflectance properties 

      Cloutis, Edward A. (Journal of Geophysical Research, 1997-11-25)
      Reflectance spectra of manganese-rich olivines were examined to determine which spectral features allow these minerals to be distinguished from forsteritic-fayalitic olivines. The results indicate that manganese-rich ...
    • Diaspores and related hydroxides' Spectral-compositional properties and implications for Mars 

      Cloutis, Edward A; Bell, James F. III (Journal of Geophysical Research, 2000-03-25)
      Differences in spectral reflectance properties (0.3-26 μm) of a suite of metal hydroxides (gibbsite, böhmite, diaspore, goethite, and manganite) have been found to be a function of both structural and compositional differences ...
    • Pyroxene reflectance spectra: Minor absorption bands and effects of elemental substitutions 

      Cloutis, Edward A. (Journal of Geophysical Research, 2002-06-13)
      Reflectance spectra of a suite of compositionally diverse pyroxenes exhibit variable spectral properties which are associated with various elemental substitutions. Those associated with transition series elements, such as ...
    • Statement on Spectroscopic Imaging in Art Conservation: A New Tool for Materials Investigations 

      Attas, Michael; Cloutis, Edward; Collins, Catherine; Goltz, Douglas; Majzels, Claudine; Mansfield, James R.; Mantscha, Henry H. (Leonardo Electronic Archive, 2002-09)
    • Spectral reflectance properties of zeolites and remote sensing implications 

      Cloutis, Edward A.; Asher, Pranoti M.; Mertzman, Stanley A. (Journal of Geophysical Research, 2002-09-25)
      The 0.3- to 26-μm reflectance spectra of a suite of 28 zeolites were measured and analyzed to derive spectral-compositional-structural relationships. Below ~7 μm, the spectra are largely dominated by absorption features ...
    • Spectroscopic Imaging in Art Conservation: A New Tool for Materials Investigations 

      Attas, Michael; Cloutis, Edward; Collins, Catherine; Goltz, Douglas; Majzels, Claudine; Mansfield, James R.; Mantsch, Henry H. (The MIT Press, 2003-08-01)
    • Mineralogic constraints on sulfur-rich soils from Pancam spectra at Gusev crater, Mars 

      Johnson, J. R.; Bell, J. F. III; Cloutis, E.; Staid, M.; Farrand, W. H.; McCoy, T.; Rice, M.; Wang, A.; Yen, A. (Geophysical Research Letters, 2007-07-06)
      The Mars Exploration Rover (MER) Spirit excavated sulfur-rich soils exhibiting high albedo and relatively white to yellow colors at three main locations on and south of Husband Hill in Gusev crater, Mars. The multispectral ...
    • Stability of hydrated minerals on Mars 

      Cloutis, Edward A.; Craig, Michael A.; Mustard, John F.; Kruzelecky, Roman V.; Jamroz, Wes R.; Scott, Alan; Bish, David L.; Poulet, François; Bibring, Jean-Pierre; King, Penelope L. (Geophysical Research Letters, 2007-10-20)
      The validity of recent identification of various hydrated minerals (kieserite, gypsum, hexahydrite, nontronite, chamosite, and montmorillonite) on Mars was assessed by exposing these minerals to simulated Martian surface ...
    • Light-toned salty soils and coexisting Si-rich species discovered by the Mars Exploration Rover Spirit in Columbia Hills 

      Wang, Alian; Bell, J. F. III; Li, Ron; Johnson, J. R.; Farrand, W. H.; Cloutis, E. A.; Arvidson, R. E.; Crumpler, L.; Squyres, S. W.; McLennan, S. M.; Herkenhoff, K. E.; Ruff, S. W.; Knudson, A. T.; Chen, Wei; Greenberger, R. (Journal of Geophysical Research, 2008-12-19)
      Light-toned soils were exposed, through serendipitous excavations by Spirit Rover wheels, at eight locations in the Columbia Hills. Their occurrences were grouped into four types on the basis of geomorphic settings. At ...
    • Distribution of hydrated minerals in the north polar region of Mars 

      Horgan, B. H.; Bell, J. F. III; Noe Dobrea, E. Z.; Cloutis, E. A.; Bailey, D. T.; Craig, M. A.; Roach, L. H.; Mustard, J. F. (Journal of Geophysical Research, 2009-01-28)
      The previous discovery of extensive deposits of hydrated minerals in Olympia Planum in the north polar region of Mars by the Mars Express OMEGA instrument raises important questions about the origin and subsequent ...
    • Temporal observations of bright soil exposures at Gusev crater, Mars 

      Rice, M. S.; Bell, J. F. III; Cloutis, E. A.; Wray, J. J.; Herkenhoff, K. E.; Sullivan, R.; Johnson, J. R.; Anderson, R. B (Journal of Geophysical Research, 2011-01-27)
      The Mars Exploration Rover Spirit has discovered bright soil deposits in its wheel tracks that previously have been confirmed to contain ferric sulfates and/or opaline silica. Repeated Pancam multispectral observations ...
    • Small-scale methane dispersion modelling for possible plume sources on the surface of Mars 

      Olsen, K. S.; Cloutis, E.; Strong, K. (Geophysical Research Letters, 2012-10-11)
      Intense interest in the characteristics of a methane source on Mars has been spurred by recent observations of a plume structure. The current NASA Mars Science Laboratory and future landers and orbiters will be tasked with ...
    • Spectroscopic approaches for studying faint text on a wooden tally from Invincible (1758) 

      Goltz, Douglas M.; Piniuta, Brent; Huebner, Erwin; Attas, Michael; Cloutis, Edward; Broomhead, John (International Journal of Conservation Science, 2013-01-01)
      In this study we describe the application of X-ray fluorescence, variable pressure scanning electron microscopy and visible (420-720 nm) hyperspectral imaging to assess the surface properties of a wood tally stick that was ...
    • Optical and radiometric models of the NOMAD instrument part I: the UVIS channel 

      Vandaele, Ann C.; Willame, Yannick; Depiesse, Cédric; Thomas, Ian R.; Robert, Séverine; Bolsée, David; Patel, Manish R.; Mason, Jon P.; Leese, Mark; Lesschaeve, Stefan; Antoine, Philippe; Daerden, Frank; Delanoye, Sofie; Drummond, Rachel; Neefs, Eddy; Ristic, Bojan; Lopez-Moreno, José-Juan; Bellucci, Giancarlo; NOMAD Team, NOMAD Team (Optics Express, 2015-11-09)
      The NOMAD instrument has been designed to best fulfil the science objectives of the ExoMars Trace Gas Orbiter mission that will be launched in 2016. The instrument is a combination of three channels that cover the UV, ...
    • Imaging spectroscopy of geological samples and outcrops: Novel insights from microns to meters 

      Greenberger, Rebecca N.; Mustard, John F.; Ehlmann, Bethany L.; Blaney, Diana L.; Cloutis, Edward A.; Wilson, Janette H.; Green, Robert O.; Fraeman, Abigail A. (GSA Today, 2015-12-01)
      Imaging spectroscopy is a powerful, non-destructive mineralogic tool that provides insights into a variety of geological processes. This remote measurement technique has been used for decades from orbital or aerial platforms ...
    • Surface albedo and spectral variability of Ceres 

      Li (李荐扬), Jian-Yang; Reddy, Vishnu; Nathues, Andreas; Le Corre, Lucille; Izawa, Matthew R. M.; Cloutis, Edward A.; Sykes, Mark V.; Carsenty, Uri; Castillo-Rogez, Julie C.; Hoffmann, Martin; Jaumann, Ralf; Krohn, Katrin; Mottola, Stefano; Prettyman, Thomas H.; Schaefer, Michael; Schenk, Paul; Schröder, Stefan E.; Williams, David A.; Smith, David E.; Zuber, Maria T.; Konopliv, Alexander S.; Park, Ryan S.; Raymond, Carol A.; Russell, Christopher T. (The Astrophysical Journal Letters, 2016-01-29)
      Previous observations suggested that Ceres has active, but possibly sporadic, water outgassing as well as possibly varying spectral characteristics over a timescale of months. We used all available data of Ceres collected ...