(01/05/2001) --- In the Spacecraft Assembly & Encapsulation Facility –2, workers help guide the 2001 Mars Odyssey Orbiter to a workstand (left). The spacecraft carries three science instruments: the Thermal Emission Imaging System (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 GRS is a rebuild of the instrument lost with the Mars Observer mission.] The MARIE will characterize aspects of the near-space radiation environment as related to the radiation-related risk to human explorers. The Mars Odyssey Orbiter is scheduled for launch on April 7, 2001, aboard a Delta 7925 rocket from Launch Pad 17-A, Cape Canaveral Air Force Station