------------------------------------------------------------------------- Explanation by Grzegorz DudziƄski (g.p.dudzinski@gmail.com), May 6, 2016: ------------------------------------------------------------------------- Intensity of a pixel corresponds to the flux/echo strength for a given frequency and time delay, so it corresponds to sum of surface area at given distance and radial velocity. I found an animations I did some time ago; hope they're useful. * https://www.youtube.com/watch?v=9J8RV0UIVtc * https://www.youtube.com/watch?v=1YrAkEvuCpg bottom right: velocities of surface elements, blue - towards observer, red - away from observer; more colour = bigger velocity top right: view of asteroid as if it was observed with photometric telescope top left: top view of asteroid (perpendicular to the line of sight) bottom left: radar image (direction to observer is upwards) The red line in the middle of echo image is just an artefact. Red colour on the echo means that signal is really strong. It was impossible to show the range of values just with grey scale. In the second video asteroid is assumed to be spinning normally about spin axis, but this motion is not shown. Instead I rolled it (changed beta) to show how the echo image looks like for different aspects. ----------------------------------------------------------------------- explanation for the mp4 movies on Aemilia and Ostro(GD, June 28, 2016): ----------------------------------------------------------------------- The colours correspond to the error of the shape. Green represents lowest error value on the surface, red the highest. The difference is we used two algorithms, for single and binary objects. The family of solutions for binary object is more consistent (the models are more alike)