Radar scattering by planetary surfaces modeled with laboratory-characterized particles

• Simulations of radar scattering using a model of a realistic planetary surface are presented.
• The effects of various chemical and geometric compositions of the surface on radar scattering are shown.
• The surface properties of asteroids, comets, and Europa are discussed based on the model.

We model radar scattering by planetary surfaces using a ray-optics algorithm that includes Fresnelian reflection and refraction, diffuse scattering, and coherent backscattering. We enhance the realism of the ray-optics algorithm by using scattering particles that are geometrically representative of the surfaces and interiors of planetary bodies. The shapes as well as the dielectric properties of the scattering particles have been characterized in laboratory. The results demonstrate the effects of various physical parameters on radar scattering with an emphasis on asteroids. We present the effects of number density, size distribution, and dielectric and geometric properties of scattering particles on the radar reflectivity and circular-polarization ratio of planetary surfaces. We also briefly discuss applications to the Galilean Moon Europa and comets.