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Introduction to selecting a reference surface The surface of any celestial body can be anything but uniform. The oceans, where existing, can be treated as reasonably uniform, but the surface or topography of the land masses can exhibit large vertical variations between mountains and valleys. These variations make it impossible to approximate the shape of ...


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Mars Reconnaissance Orbiter has a camera called HiRISE (High Resolution Imaging Science Experiment), launched in 2005-08-12, which is the highest resolution camera in orbit of Mars at an altitude that varies from 200 to 400 kilometers (about 125 to 250 miles) above the martian surface by Carrier rocket Atlas V-401. The High Resolution Imaging Science ...


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For Mars, the current definition of 0 km is derived from data from the Mars Orbiting Laser Altimeter (MOLA) data from Mars Global Surveyor. In fact the altitude reference is referred to as "MOLA altitude". You would say for example: "minus 1.4 km MOLA". From the paper: Zero elevation on Mars from MOLA is defined as the equipotential surface (...


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The article contains several bits of information that will be useful: Extensive fields of large fractured plate-like features on a horizontal surface are visible near the south end of the High Resolution Stereo Camera (HRSC) imaging strip taken on 19 January 2004 (Fig. 1). This area has previously been covered by NASA high-resolution Mars Orbiter Camera (...


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NASA confirms the latter - 2600m: The depth of the crater -- about 2.6 kilometers (1.6 miles) -- also demonstrates that Mojave has experienced little infilling or erosion. The terrain was mapped using stereo pairs of images from the HiRISE imager on the Mars Reconnaissance Orbiter. I believe the confusion is from comparing depth vs elevation. Mojave ...


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The Planetary Data System (PDS, pds.nasa.gov) contains data (including imagery) collected from all NASA planetary missions, including, of course, Mars. The PDS repositories include an entire archive (they call it a "node") devoted to Cartography and Imaging Sciences (the IMG node). Visit PDS: The Planetary Data System. Select the Data Search tab. In the "...


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The reference datum is usually chosen to be about the average altitude. For example, on Mars, the datum, known as the Mars areoid, is very close to the average radius of Mars, as measured round the equator. (It was defined by the height at which the pressure corresponds to the triple point of water.) In reality it wouldn't matter very much what the ...


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