Engineering topics

Maurice, Kelly E.

Publications and source records attributed to Maurice, Kelly E..

3 records

NASA NTRS1994

Venus surface roughness and Magellan stereo data

Presented are results of some studies to develop tools useful for the analysis of Venus surface shape and its roughness. Actual work was focused on Maxwell Montes. The analyses employ data acquired by means of NASA's Magellan satellite. The work is primarily concerned with deriving measurements of the Venusian surface using Magellan stereo SAR. Roughness was considered by means of a theoretical analyses based on digital elevation models (DEM's), on single Magellan radar images combined with radiometer data, and on the use of multiple overlapping Magellan radar images from cycles 1, 2, and 3, again combined with collateral radiometer data.

Maurice, Kelly E.↗

NASA NTRS1992

Images and topographic relief at the north pole of Venus

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 is reported. Images at 13 distinctly different azimuths are reported that range over 360 deg in longitude and that show the topographic relief at vastly different imaging geometries at intervals of about 20 deg. 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 multiimage clinometric approach. It is shown that the pole is located in accentuated topography with elevation differences in the range of no more than 1 km. It is concluded 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).

Leberl, Franz W.↗

NASA NTRS1992

Initial results from the Magellan stereo experiment

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 with +/- 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 deg. 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.

Leberl, Franz W.↗