Is The Opposition Effect of Saturn’s Rings Caused by Coherent Backscattering?

Abstract

Theoretical studies by Shkuratov (1988 and 1991), Muinonen (1989 and 1990), and Muinonen et al. (1991) have indicated the importance of coherent (or enhanced) backscattering for interpreting observations of the regoliths of atmosphereless solar system bodies. My work concentrated on scattering by two dipole particles (dipole ↔ dipole), scattering by a dipole particle close to an interface (dipole ↔ surface), and second-order external reflection from two spheres large compared to the wavelength (surface ↔ surface), and I showed that the coherent backscattering peak is unequivocally accompanied by a reversal of linear polarization. The calculations indicate the task of modeling: for all particle and surface roughness sizes, and for all volume densities, studies of electromagnetic scattering by single particles, their rough surface structures, and scattering by volumes consisting of such particles need to be carried out.