Spectral analysis and compositing techniques for the Near Earth Asteroid Rendezvous (NEAR Shoemaker), X-ray and Gamma-Ray Spectrometers (XGRS)

An X-ray and Gamma-Ray Spectrometer (XGRS) is on board the Near Earth Aster oid Rendezvous (NEAR) spacecraft to determine the elemental composition of the surface of the asteroid 433 Eros. The Eros asteroid is highly oblate an d irregular in shape. As a result, analysis methodologies are in many ways a divergence from comparable techniques. Complex temporal, spatial and inst rument performance relationships must be accounted for during the analysis process. Field of view and asteroid surface geometry measurements must be m odeled and then combined with real measurements of solar, spectral and inst rument calibration information to derive scientific results. NEAR is curren tly orbiting 433 Eros and is in the initial phases of its primary data inte gration and mapping phases. Initial results have been obtained and bulk che mistry assessments have been obtained through specialized background assess ment and data reduction techniques. (C) 2001 Published by Elsevier Science B.V.