Charging and Discharge in Vacuum and Space

Success of vacuum electronic devices often depends on secure electrical insulation of the components. The presence of solid insulator significantly decreases the insulation strength of the vacuum apparatus. Charging of solid insulator in the pre-breakdown process enhances the electric field near the triple junction and leads to electrical discharge. Electrostatic discharge (ESD) on spacecraft surface is similar to other vacuum electronics devices with insulator bridge but differs in two points that there is no secure electrical ground and no distinct anode. ESD phenomena on spacecraft solar array are reviewed as typical example of discharge in space.