Visible and near-infrared multispectral analysis of geochemically measured rock fragments at the Opportunity landing site in Meridiani Planum

Journal of Geophysical Research E: Planets
By: , and 

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Abstract

We have used visible and near‐infrared Panoramic Camera (Pancam) spectral data acquired by the Opportunity rover to analyze 15 rock fragments at the Meridiani Planum landing site. These spectral results were then compared to geochemistry measurements made by the in situ instruments Mössbauer (MB) and Alpha Particle X‐ray Spectrometer (APXS) to determine the feasibility of mineralogic characterization from Pancam data. Our results suggest that dust and alteration rinds coat many rock fragments, which limits our ability to adequately measure the mineralogy of some rocks from Pancam spectra relative to the different field of view and penetration depths of MB and APXS. Viewing and lighting geometry, along with sampling size, also complicate the spectral characterization of the rocks. Rock fragments with the same geochemistry of sulfate‐rich outcrops have similar spectra, although the sulfate‐rich composition cannot be ascertained based upon Pancam spectra alone. FeNi meteorites have spectral characteristics, particularly ferric oxide coatings, that generally differentiate them from other rocks at the landing site. Stony meteorites and impact fragments with unknown compositions have a diverse range of spectral properties and are not well constrained nor diagnostic in Pancam data. Bounce Rock, with its unique basalt composition, is easily differentiated in the Pancam data from all other rock types at Meridiani Planum. Our Pancam analyses of small pebbles adjacent to these 15 rock fragments suggests that other rock types may exist at the landing site but have not yet been geochemically measured.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Visible and near-infrared multispectral analysis of geochemically measured rock fragments at the Opportunity landing site in Meridiani Planum
Series title Journal of Geophysical Research E: Planets
DOI 10.1029/2010JE003660
Volume 115
Issue E7
Year Published 2010
Language English
Publisher American Geophysical Union
Contributing office(s) Astrogeology Science Center
Description 29 p.
Other Geospatial Meridiani Planum, Mars