The second global radar image coverage of Venus by Magellan included a 1 day experiment to produce a set of eight images along orbits that combined with the original nominal imagery into stereo image pairs suited for visual stereo interpretation and mapping of topographic elevations. Initial analysis shows excellent stereo radar data with good vertical exaggeration of six and more, parallax accuracies of ±0.6 pixels or ±45 m and a surface definition within ±30 m. The topographic relief can be very accentuated, with local elevation differences of 2.5 km and terrain slopes often in excess of 25°. This data set has proven the usefulness of global stereo coverage and marks the beginning of significant planetary stereo radargrammetric developments. Extensive mapping with this same stereo geometry is being carried out in cycle 3, and preparations are underway to develop a detailed stereo radargrammetric topographic model of the planet.

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We report on the analysis of unique coverage of the north pole of Venus using a subset of 13 images from a total of about 775 synthetic aperture radar orbits during cycle 1 of the Magellan mission. We present images at 13 distinctly different azimuths that range over 360° in longitude and that show the topographic relief at vastly different imaging geometries at intervals of about 20°. A pair of intersecting or crossing orbits is used to assess the topographic relief with stereo radargrammetric techniques, and to refine this assessment using a multi‐image clinometric approach. We show that the pole is located in accentuated topography with elevation differences in the range of no more than 1 km. We conclude that pinpointing the location of the pole from the overlapping images and standard mission data is accurate to within about 100 pixels or 8 km (RMS).

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