Data management and analysis techniques used in the near x-ray and gamma-ray spectrometer systems

The NEAR Earth Asteroid Rendezvous (NEAR) spacecraft will encounter the 433 Eros asteroid for a one year orbital mission in December 1998. Its on-board remote sensing instrumentation includes X-ray and gamma-ray (XGRS) spectro meters. NEAR is an orbital mission and long integrations over spatially spe cific asteroid regions are generally not possible. A methodology for simula ting longer integrations has been developed for XGRS and uses unique manage ment, correlative and analytical ground systems to render mapping data prod ucts. Evaluation of the spatial environment is accomplished through virtual renderings of the asteroid surface giving incidence, emission and surface roughness factors. Extended computer plate modeling information is employed to optimize ground computer systems processing time. Interactive visualiza tion systems have been developed to manage close to a million spectra that will be collected during the encounter. Feedback systems are employed to in spect, tag and calibrate spectral data products. Mission planning, systems development and managerial responsibilities have been distributed to cooper ating science organizations at The Goddard Space Flight Center, The Univers ity of Arizona, Cornell University, The Applied Physics Laboratory and The Max Plank Institute. (C) 1999 Elsevier Science B.V. All rights reserved.