DeMeo taxonomy : categorization of asteroids in the near-infrared

Abstract

This work presents the DeMeo taxonomy, an asteroid taxonomy with 24 classes based on Principal Component Analysis of spectral data over the visible and near-infrared wavelengths, specifically the 0.45 to 2.45 micron range. Principal Component Analysis was used by both Tholen (1984) and Bus (1999) to create taxonomies on visible data. There is no pre-existing taxonomic system for the entire suite of asteroid characteristics because only in the current decade has spectral data collection become available in the near-infrared for asteroids down to relatively faint (V= 17) limiting magnitudes. (Rayner et al. 2003) With a larger data range, which includes important absorption features at one and two microns suggesting the presence of minerals, there is a need for an extended system to encompass this range of information. In this work we explain the process of creating the taxonomy, the method for finding an object's taxonomic class under this system, and present spectral types for the 365 objects that were used to create the system.