Radio reflection imaging of asteroid and comet interiors II: Results and recommendations

Radio reflection imaging of asteroid and comet interiors I: Acquisition and imaging theory

“…1. Of all factors influencing the imaging quality, the accuracy of the velocity model turns out to make the largest impact, as discussed in detail by Grimm et al (2014). In general, the velocity model inside the asteroid is not known a priori and has to be determined in an iterative tomographic process akin to the well-known waveform inversion.…”

“…The model accuracy and attenuation questions are addressed by Grimm et al, 2014. In our acquisition setup, the multi-offset experiment aperture depends on the acquisition duration, i.e. the total number of revolutions around the asteroid.…”

“…However, since our focus in this paper is on acquisition and imaging, we do not discuss in greater details the impact of attenuation on the reconstructed images. The impact of attenuation in radar imaging is discussed by Grimm et al (2014). In the following examples, we employ wave operator shown in Eq.…”

“…Our focus is mainly on the imaging aspects and the improved image quality due to the higher data volume obtained using the dual orbiter setup. More details and a quantitative analysis of imaging results are provided by Grimm et al (2014).…”

“…Our methodology expands on earlier studies Benna et al, 2002;Carley and Heggy, 2008 investigating the applicability of radar wave propagation through complex comet nuclei using time-domain finite-difference wave propagation (FDTD). A companion paper, Grimm et al, 2014, addresses issues related to acquisition and target parameters and gives quantitative measures of image reconstruction accuracy; this paper also discusses some assumptions related to model parameters characterizing electromagnetic wave propagation speed and attenuation.…”