Spacecraft Charge Monitor

Electrostatic charging can damage spacecraft, cause instrument biases that limit the accuracy of scientific measurements, and poses a direct hazard to personnel during extravehicular activity. There are now few options available for monitoring spacecraft charge. An inexpensive, compact, reliable, easily deployed spacecraft charge monitor is needed. Goembel Instruments has developed just such an instrument - the Spacecraft Charge Monitor (SCM). In Phase I we built and tested a prototype SCM. Results from Phase I show that the SCM will revolutionize the field of spacecraft charge detection. The 500 gram, 1 Watt, instrument will be able to determine spacecraft floating potential to within 0.1 volt for each second in flight. The SCM's performance represents an order of magnitude improvement over what is available now. In Phase II we will advance the SCM from laboratory prototype to flight prototype. We will develop flight electronics, a flight sensor head, calibrate the instrument, put it through a series of tests for flight worthiness, and deliver the fully tested flight instrument and documentation to NASA. The Phase II work will produce an SCM for flight tests, and will prepare us for the Phase III production of instruments.