Aerospace: Neutralizing charged-up spacecraft: Electrical charge gathered from space plasma can cause malfunctions or failure, but techniques for minimizing its effects are available

As early as 1969, telemetered data from the National Aeronautics and Space Administration's ATS-5 satellite suggested that the satellite was charging to potentials of more than 10 000 volts relative to the ambient space environment. In 1971, several U.S. Air Force satellites again showed the effects of high surface charges. The symptoms, in all cases: logic circuits switched erratically, sensor signals grew noisy, heat-control mechanisms lost efficiency, and attitude control faltered. The satellites recorded false data and initiated unplanned actions. In 1973, a satellite in the U.S. Defense Communications System actually failed because its power supply malfunctioned.