Surface Interactions

Surface Erosion

Every time a particle impacts a surface there is a chance that it will knock off or “sputter” some material from the surface. Over time this can cause noticeable degradation in high flux areas such as Hall thruster channels, electrostatic acceleration grids, etc. Even structures far downstream of a thruster can erode over time if they are near the main plume. This article explains the basic algorithms involved in determining how a surface will erode when exposed to a given flux.

Spacecraft Surface Charging

A spacecraft acts as an isolated probe and will become charged due to the presence of space plasma. Surface potential will change due to the thermal motion of electrons and ions. The potential will continue to change until the fluxes of the negative and positive charges perfectly balance each other. In this article we discuss the basics behind spacecraft charging and provide a simple spacecraft charging code example.