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Hydrous carbonates on Mars?: Evidence from Mariner 6/7 infrared spectrometer and ground‐based telescopic spectra Hydrous carbonates on Mars?: Evidence from Mariner 6/7 infrared spectrometer and ground‐based telescopic spectra

Absorption features at 2.28 and 5.4 μm identified in Mariner 6/7 infrared spectrometer and terrestrial telescopic spectra are consistent with the spectra of hydrous magnesium carbonates such as hydromagnesite and artinite. Spectral characteristics of these hydrous carbonates are different from those of the anhydrous carbonates, as the former do not have the strong spectral features...
Authors
W. Calvin, T. King, Roger Clark

The U. S. Geological Survey, Digital Spectral Library: Version 1 (0.2 to 3.0um) The U. S. Geological Survey, Digital Spectral Library: Version 1 (0.2 to 3.0um)

We have developed a digital reflectance spectral library, with management and spectral analysis software. The library includes 498 spectra of 444 samples (some samples include a series of grain sizes) measured from approximately 0.2 to 3.0 um . The spectral resolution (Full Width Half Maximum) of the reflectance data is
Authors
Roger Clark, Gregg Swayze, Andrea Gallagher, Trude King, Wendy Calvin

SPECtrum Processing Routines User's Manual Version 3 (program SPECPR) SPECtrum Processing Routines User's Manual Version 3 (program SPECPR)

Introduction The SPECtrum Processing Routines (SPECPR) is a large-scale interactive program for general one-dimensional array processing and optimized for reflectance spectroscopy data and analysis. The program processes one-dimensional arrays up to 4852 data points and the operations include addition, subtraction, multiplication, division, trigonometric functions, logarithmic and...
Authors
Roger N. Clark

Spectral Distinctions between the Leading and Trailing Hemispheres of Callisto: New Observations Spectral Distinctions between the Leading and Trailing Hemispheres of Callisto: New Observations

An analysis of recent telescopic observations of Callisto results in new insights regarding spectral variations from the leading to the trailing hemisphere of Callisto. Examination of data in the wavelength range from 2.0 to 2.5 ??m indicates that previous suggestions of spectral differences are most likely the result of experimental uncertainty or error. Slight variations in the slope...
Authors
W. Calvin, R. Clark

Evidence for ammonium-bearing minerals on Ceres Evidence for ammonium-bearing minerals on Ceres

Spectra obtained from recent telescopic observation of 1-Ceres and laboratory measurements and theoretical calculations of three component mixtures of Ceres analog material suggest that an ammoniated phyllosilicate is present on the surface of the asteroid, rather than H2O frost as had been previously reported. The presence of an ammoniated phyllosilicate, most likely ammoniated saponite...
Authors
Trude V. V. King, Roger N. Clark, W. M. Calvin, David M. Sherman, R. H. Brown
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