It is well known that spacecrafts on orbits are charged up due to the interaction with space plasma and high energy charged particles. Those charging phenomena are categorized into two. One is “surface charging” and the other is “internal charging”. The surface charging involves absolute charging of the conductive satellite body and differential charging occurring on different surface materials on the satellite. On the other hand, the internal charging occurs on the insulating materials and/or electrically floating conductors installed inside the spacecraft body. When the level of the differential charging and/or internal charging reaches some threshold, ESD's (Electrostatic Discharges) will possibly occur. The author reviewed these ESD phenomena based on the ground experiments simulating space environments.
