Discrimination of Lunar Rock and Soil Types by Simulated Multispectral SSI Data.

Abstract

During the Earth-Moon encounter 1 of the Galileo mission, the SSI Experiment will acquire multispectral images in 7 colors of the lunar surface. A Major goal in evaluating these data is the mapping of spectral surface units and their interpretation in terms of lithology and composition. In order to assess the discrimination of different lunar rock and soil types from the SSI multispectral data, laboratory reflectance measurements with high spectral resolution of lunar samples were used to simulate possible SSI reflectance values. The results are compared with the reflectance values received by applying the spectral response mathematical model. The SSI signatures determined for the lunar samples are analyzed by using the relative reflectance values and reflectance data normalized at 0.56 ym. The normalized data deserve special interest because the transformation of the SSI multispectral imaging data into spectral reflectance data remains unresolved so far. The separability of lunar spectra and hence, lunar samples, is examined by means of a principal component analysis.