Measurement of the electrostatic field in the stratosphere

The electrostatic field in the altitude range 10 to 30 km was measured. In a field radiosonde which is based on the collector principle large disks were used in place of the usual radioactive probes, and many of the disadvantages of probes were eliminated. Results of three balloon releases made from Melbourne, Australia, showed that the potential gradient decreased from about 4 v/m at 10-km altitude to about 0.5 v/m at 25 km. The transient behavior of the apparatus provides a means also of measuring the conductivity of the air, though no results on conductivity have been obtained so far.