Electrostatic dust transport on the terminator of atmosphereless bodies

Abstract

Small dust particles may levitate over the surface of atmosphereless bodies, but to study electrostatic dust transport during a complete rotational period it is necessary to evaluate the surface potential at the terminator zone. We simulate the photo-electron layer and the dust charging process according to previously used models for dust levitation, but we propose a modification of the models to add the effects produced by surface roughness for low solar elevation angles. The correction for surface roughness on the model showed that a positive value for the surface potential and the electric field appear at the terminator. We found that submicron particles could be in stable levitation for small gravity fields. Our results also showed that the finest regolith grains can be lost into space due to the electrostatic repulsion.