Table 4‑1: List of electrostatic and other plasma interaction effects on space systems

Spacecraft reference potential change (e.g. so-called spacecraft high voltage charging)

Differential surface charging

Internal surface charging

Deep-dielectric charging

Surface charging effects on e.g. plasma instruments

Charging interactions with thruster plumes

Charging induced sputtering

Charging induced contamination

Dust charging and sticking

Electrostatic sticking (SA, inflatables, solar sails, dusts)

Charging differences in docking procedures and EVA

Material modifications (e.g. electric field induced conductivity, plasma-contaminant modifications, cracking e.g. of ITO)

Tether systems and vxB induced voltages and currents

Interference induced by electrostatic sheath and induced plasma on EM systems

Spontaneous discharges

Triggered discharges:

- Thruster-triggered

- Low voltage discharges (e.g. Paschen and secondaries)

- Sunlit/shadow triggered discharges

- triggered by micro particles

- triggered by natural high density plasma

Synergistic secondary low-voltage discharges (e.g. on solar array)

Power loss and current flow from exposed elevated voltage systems

Photoelectron cloud induced charging and disturbance of plasma sensors

Plasma perturbation from microparticle impacts (e.g. antennas)

Active plasma sources (e.g. emitters, thrusters, contactors)

If a surface is maintained at high potential, it draws a current from the plasma, particularly in the dense LEO environment. This is an issue with exposed solar array interconnects because this leakage current drains power from the array. In addition the floating potential of the spacecraft can be altered as a result.

The magnitude of spacecraft plasma interaction effects varies greatly with the changes in the ambient plasma from one type of Earth orbit to another. Also the plasma environment can exhibit temporal changes along the orbit and as a result of so-called ‘Space Weather’. In addition, the spacecraft itself can modify the plasma environment e.g. via thruster firings, active experiments, or debris impacts. Other aspects of the space environment besides plasma can also influence the plasma interaction e.g. radiation, contamination, and temperature.

In any case, it is important to have access to a good quantitative description of the space environment. Suitable descriptions and models of the space environment, including aspects that control charging effects, can be found in ECSS-E-ST-10-04.