Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8137972 | Icarus | 2014 | 16 Pages |
Abstract
We have discovered an absorption band centered at 0.72 μm in localities of DM that show the lowest albedo values by using FC data as well as spectral information from Dawn's imaging spectrometer VIR. Such localities are contained within impact-exposed outcrops on inner crater walls and ejecta material. Comparisons between spectral FC in-flight data, and laboratory spectra of meteorites and mineral mixtures in the wavelength range 0.4-1.0 μm, revealed that the absorption band can be attributed to the mineral serpentine, which is typically present in CM chondrites. Dark material in its purest form is rare on Vesta's surface and is distributed globally in a non-uniform manner. Our findings confirm the hypothesis of an exogenic origin of the DM by the infall of carbonaceous chondritic material, likely of CM type. It further confirms the hypothesis that most of the DM was deposited by the Veneneia impact.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Space and Planetary Science
Authors
Andreas Nathues, Martin Hoffmann, Edward A. Cloutis, Michael Schäfer, Vishnu Reddy, Ulrich Christensen, Holger Sierks, Guneshwar Singh Thangjam, Lucille Le Corre, Kurt Mengel, Jean-Baptist Vincent, Christopher T. Russell, Tom Prettyman,