THEMIS infrared camera was designed to be used in conjunction with data from the Thermal Emission Spectrometer (TES), a similar instrument on Mars Global Surveyor. While THEMIS has a very high spatial resolution (100 m) with a low spectral resolution of only 10 bands between 6 and 15 micrometers, TES has a low spatial resolution (3×6 km) with very high spectral resolution of 143 bands between 5 and 50 micrometers. The instrument's approach provides data on localized deposits associated with volcanoes, hydrothermal processes, and the alteration of minerals by surface and/or subsurface water. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), an Earth orbiting instrument on the Terra spacecraft, has used a similar approach to map the distribution of minerals on Earth. Variations in the thermal infrared false-color image are due to differences in the minerals that make up rocks and soil. Discovery of a variety of rocks THEMIS found a wide range of igneous rocks and minerals. Some of the rocks were low-silica basalts, high silica dacite, olivine basalts, ultramafic (picritic) basalts, and quartz-bearing granitoid rocks. The olivine basalts were present in a variety of locations, such as on crater floors and in some canyon wall layers. The mineral olivine is important because it is common in more primitive magmas from the mantle and it weathers quickly when moisture is present. So, if olivine is present, the climate must have been dry since the time that olivine was exposed. Quartz-bearing rocks were found in the central uplifts in craters. Rocks in the central uplifts were probably once buried several kilometers beneath the surface, but raised by the impact process. Rocks of dacite composition show that, within magma chambers, fractional crystallization occurred. In this process, some minerals form crystals, then settle to the bottom of the chamber. Having a variety of rocks increases the chances that some useful/valuable minerals may be found on Mars. Visible camera THEMIS has a visible imaging camera that acquires data in five spectral bands, takes images with a spatial resolution of 18 m (59'), and can resolve objects about the size of a semi-trailer. This resolution is intermediate between large-scale images from the Viking Orbiters (150 to 300 meters per pixel) and the high-resolution images from the Mars Orbiter Camera (MOC) on board Mars Global Surveyor (1.5 to 3 meters per pixel). Visible images from THEMIS are usually close to 20 km wide (12