Dusty Plasma near the Surface of Saturn’s Moon Enceladus

Abstract

It has been shown that a dusty plasma is formed in a layer over the illuminated surface of Saturn’s moon Enceladus due to photoelectric and electrostatic processes. Using a physicomathematical model to self-consistently describe the densities of photoelectrons and dust particles over the illuminated surface of Enceladus, distribution functions of photoelectrons near the surface, as well as the altitude dependences of electric fields and the density, charge, and size of dust particles, have been determined. It has been demonstrated that the photoelectric effect is an important process for the formation of the dusty plasma despite a large distance from Enceladus to the Sun. It has been shown that the density of photoelectrons over the surface of Enceladus can be an order of magnitude higher than the density of electrons and ions of the solar wind, and sizes of levitating dust particles exceed the characteristic sizes of dust particles rising over the surface of the Moon.