Statement of the problem and experimental study of the secondary arcing in the conditions of orbital space

The problem of breakdowns in equipment of spacecrafts operating on the Earth´s orbit is based on multifactor physics involving vacuum electronics, plasma physics, and gas discharge physics. The problem was strongly escalated with increase of operating voltages from 27 V to 100 V followed by even higher voltages in the future. The problem is studied intensively in the course of last ten years, and the present state of art came to standards regulating approaches to reduce the risks of secondary arcing and to regulate the test protocols. Nevertheless, the research work on the matter must be continued as far as a lot of factors are still omitted in the mentioned above standards. The present work contains results of measurements of threshold conditions of secondary arcing in various insulating gaps as the residual gas pressure goes down from atmosphere to high vacuum, and the primary discharge is similar to the fuse-triggered, low-current arc discharge. In such conditions, the results indicate the breakdown strength to correspond to the cathode voltage drop rather than the Paschen curve minimum. Experimental results are compared with results of computer simulation.