The use of probing electrodes in the study of the ionosphere

The Langmuir probe and its developments provide a means whereby such important ionospheric quantities as electron concentration and temperature, and ion mass spectrum, concentration and temperature may be measured. These quantities are of fundamental importance in any consideration of the ion and electron equilibrium in the ionosphere. The problems involved arise largely because the vehicle is isolated from Earth and because of the varying aspect of the vehicle. They thus require very careful study before any instrumentation is built and their solution involves the use of special techniques which are not needed in the laboratory. The ways in which the problems have been tackled will be discussed and special reference will be made to the instrumentation planned for the first Anglo-U.S. satellite.