Revealing the properties of Chuyurmov-Gerasimenko's shallow sub-surface through CONSERT's measurements at grazing angles

Abstract

International audienceThe aim of the Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT) is the characterization of the inner structure and electrical properties of the Chuyurmov-Gerasimenko's nucleus. The instrument will sound the comet's nucleus between the lander Philae at the comet's surface and the Rosetta main spacecraft. A coarse three-dimensional model of the complex dielectric permittivity inside the nucleus will be reconstructed from the whole set of data obtained during the first science phase [3]. The work presented here show how a limited set of data acquired at grazing angles during a single low altitude fly-by can be used to characterize the shallow sub-surface of the nucleus. The study is based on simulated data obtained by two different electromagnetic models: the accurate pseudo spectral time-domain method and a much faster ray-based approximation taking into account material and path-loss