Satellite Differential Charging Driven by Photoelectron Currents in Disturbed Plasma Environments

This study examines how photoemission affects the differential charging of satellite structures during the transition between eclipse and sunlit phases under a turbulent plasma environment. The absence and presence of solar flux during an eclipse and during sunlight conditions induce a positive potential leading to differential charging between sunlit and shaded areas. Despite this, spacecraft can still achieve a significant negative potential in sunlight conditions. The presented investigation focuses on the primary photoemission effect of surface reflective properties through analytical methods and numerical simulations. The disparity in charging generates an electric field on shaded surfaces that extends to sunlit sides, forming a potential barrier that curtails photoemission. This paper is focused on the effect of direct consequences of photoemission on satellite charging in both normal and worst-case GEO environmental conditions. The obtained results will be helpful in satellite design and operation under challenging space conditions.