Statistical topography of PHOBOS
Abstract
Two statistical photoclinometric methods were developed to recover information on the small scale topography of an atmosphereless solar system body. The methods are applicable if the area under consideration does not exhibit dominating features such as large hills or craters, but shows clearly defined shadowed portions (shadow method) or variations in the surface brightness (brightness method). The shadow method is independent of any albedo variations on the illuminated fraction of the surface. On the other hand, when the scattering law is well known and the amount of shadows on the surface is negligible, the brightness method can be utilized to recover the surface statistics. The statistical methods are especially meant for studies where the detailed reconstruction of the surface is not nescessarily needed. Both methods were verified through numerical simulations of Gaussian surfaces. Preliminary results were obtained for the statistical topography of Phobos using the brightness method. On the investigated parts of Phobos' surface the standard deviation of slopes, the standard deviation of heights and the correlation length are of the order of 0.2, 10 m, and 50 m, respectively.
 Publication:

Finnish Space Researchers Meeting
 Pub Date:
 1990
 Bibcode:
 1990fnsr.meet...33M
 Keywords:

 Brightness;
 Photogrammetry;
 Shadows;
 Statistical Analysis;
 Terrain Analysis;
 Topography;
 Digital Simulation;
 Phobos;
 Standard Deviation;
 Surface Properties;
 Lunar and Planetary Exploration