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Today's VIS image shows part of Karzok Crater. This crater is one of two located on the flanks of Olympus Mons. Karzok Crater is 15.6km (9.7 mi) in diameter.

Olympus Mons is the largest volcano in the solar system, reaching heights over 40 km (25 miles) tall from base to summit, with the base covering an area as large as the state of Arizona. For comparison, Mauna Loa is 9 km (5.5 miles) tall measured from its base on the sea floor.

The THEMIS VIS camera is capable of capturing color images of the Martian surface using five different color filters. In this mode of operation, the spatial resolution and coverage of the image must be reduced to accommodate the additional data volume produced from using multiple filters. To make a color image, three of the five filter images (each in grayscale) are selected. Each is contrast enhanced and then converted to a red, green, or blue intensity image. These three images are then combined to produce a full color, single image. Because the THEMIS color filters don't span the full range of colors seen by the human eye, a color THEMIS image does not represent true color. Also, because each single-filter image is contrast enhanced before inclusion in the three-color image, the apparent color variation of the scene is exaggerated. Nevertheless, the color variation that does appear is representative of some change in color, however subtle, in the actual scene. Note that the long edges of THEMIS color images typically contain color artifacts that do not represent surface variation.

Orbit Number: 86755 Latitude: 18.2292 Longitude: 228.192 Instrument: VIS Captured: 2021-07-05 17:12

Please see the THEMIS Data Citation Note for details on crediting THEMIS images.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Science Mission Directorate, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.