(02/28/2001) --- Two solid rocket boosters, in the background, are lifted up the gantry on Launch Pad 17-A, Cape Canaveral Air Force Station, for stacking with a Delta 7925 rocket. The rocket, scheduled to launch April 7, 2001, will carry the 2001 Mars Odyssey Orbiter, containing three science instruments: THEMIS, the Gamma Ray Spectrometer (GRS), and the Mars Radiation Environment Experiment (MARIE). THEMIS will map the mineralogy and morphology of the Martian surface using a high-resolution camera and a thermal infrared imaging spectrometer. The GRS will achieve global mapping of the elemental composition of the surface and determine the abundance of hydrogen in the shallow subsurface. The MARIE will characterize aspects of the near-space radiation environment with regards to the radiation-related risk to human explorers