Study on data aquisition and modeling for identifying the ordinary chondrite type through visible and near-infrared reflectance spectroscopy.

Abstract

In order to Identify the surface mineral composition, meteorite type, and the degree of space weathering of the surface of the S-type asteroid Itokawa by the Hayabusa Spacecraft, we have started a research project of data acquisition and modeling of visible and near-infrared reflectance spectra of L and LL chondrite samples which are candidate materials for Itokawa. Although derivation of absorption band parameters using the modified Gaussian model with space weathering is a powerful method, the stability of its solutions with limited data poses a problem. Curve fitting using a mixing model may provide stable and reliable results depending on the quality and quantity of laboratory data. Especially, how to deal with three absorption bands of olivine in the 1-mm region will become a key to solve problems.