Spatially Resolved Mid-IR Spectra from Meteorites; Linking Composition, Crystallographic Orientation and Spectra on the Micro-Scale

Abstract

Spectral data from spacecraft are often used to infer the surface mineralogy of a body by unmixing the bulk spectrum into constituent components and comparing these to spectral databases [e.g. 1, 2]. It is widely accepted that mineral spectra derived from meteorites can provide a more accurate match to their parent body than terrestrial databases alone [3, 4]. Recent work has sought to resolve mid-IR spectra in Martian pyroxenes in terms of crystallographic orientation [3] and zonation [5], and more generally for Martian meteorites using the increased spatial resolution of synchrotron-source µFT-IR [6]. Linking these studies together, one can extract a suite of Martian-specific mineral spectra with respect to various Martian meteorites, both Shergottites and Nakhlites, which should provide a more precise match to the phases observed on the Martian surface. This study looks further than Martian meteorites alone, to also include both HEDs for comparison to Vesta and LL Chondrites to Itokawa, in order to define comparable mineral spectra throughout the solar system