Experimental Design for Direct Diagnostics of Flashover Plasma Propagation Velocity

During their operational lifetime spacecraft are subjected differential charging effects caused by the space weather environment. The differential charging of materials on s spacecraft eventually drives dielectrics, insulators and conductors used in spacecraft construction to develop differential potentials relative to the spacecraft ground. In areas known as triple junctions, the contact region between differentially biased, electrically dissimilar materials and the space plasma environment, the differential bias can reach breakdown conditions and primary arcs can occur. When a primary arc strike occurs near a charged surface, blown off material from the arc site generates a multi-species plasma that expands across the spacecraft surface. As the plasma expands, it collects the charge accumulated on the spacecraft, feeding it back into the arc site and contributing to the arc energy in an event known as a flashover discharge.