Challenges in detecting olivine on the surface of 4 Vesta
Article first published online: 30 JUL 2013
Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Meteoritics & Planetary Science
Volume 48, Issue 11, pages 2155–2165, November 2013
How to Cite
Beck, A. W., McCoy, T. J., Sunshine, J. M., Viviano, C. E., Corrigan, C. M., Hiroi, T. and Mayne, R. G. (2013), Challenges in detecting olivine on the surface of 4 Vesta. Meteoritics & Planetary Science, 48: 2155–2165. doi: 10.1111/maps.12160
- Issue published online: 16 DEC 2013
- Article first published online: 30 JUL 2013
- Manuscript Accepted: 14 JUN 2013
- Manuscript Received: 25 NOV 2012
- NASA Dawn at Vesta Participating Scientist
Identifying and mapping olivine on asteroid 4 Vesta are important components to understanding differentiation on that body, which is one of the objectives of the Dawn mission. Harzburgitic diogenites are the main olivine-bearing lithology in the howardite-eucrite-diogenite (HED) meteorites, a group of samples thought to originate from Vesta. Here, we examine all the Antarctic harzburgites and estimate that, on scales resolvable by Dawn, olivine abundances in putative harzburgite exposures on the surface of Vesta are likely at best in the 10–30% range, but probably lower due to impact mixing. We examine the visible/near-infrared spectra of two harzburgitic diogenites representative of the 10–30% olivine range and demonstrate that they are spectrally indistinguishable from orthopyroxenitic diogenites, the dominant diogenitic lithology in the HED group. This suggests that the visible/near-infrared spectrometer onboard Dawn (VIR) will be unable to resolve harzburgites from orthopyroxenites on the surface of Vesta, which may explain the current lack of identification of harzburgitic diogenite on Vesta.