Mineralogically Testing the Bus-DeMeo Taxonomy Using Meteorite Spectra

Asteroids are currently classified by the shapes of their reflectance spectra in the visible and near-infrared wavelength regions using the Bus-DeMeo taxonomy. However, very little is known about whether the asteroid classes are mineralogically distinct. To test the taxonomy, ~2,000 meteorite reflectance spectra from the RELAB database were categorized using the Bus-DeMeo classification system. All asteroid classes appear to be represented among the meteorite spectra. Approximately 40% of the meteorite spectra had to be visually classified because the Bus-DeMeo classification program produced ambiguous results. As expected, we find the HED (howardites, eucrites, diogenites) spectra to be classified primarily as V-types while ureilite spectra fall under a wide variety of asteroid classes that range from C- to S- to X-complex plus K- and Q-types. Ordinary chondrite spectra tend to be classified as S-complex bodies. Iron meteorite spectra tend to be grouped into either the X-complex or D-type classes. We are now investigating the possible range of mineral and compositional diversity in each asteroid class. This work will give insight on the reliability of each taxonomic class in grouping bodies with similar mineralogies.