Observation of double‐layer‐like structures at rocket altitudes

We have observed 230 large amplitude electric field pulses in a rocket flight to an apogee of 585 km over an aurora. While the limitations of the instrumentation only allow limits to be set on the characteristics of these pulses, the limits are nevertheless significant. A typical lower limit on the potential jump of the pulses (see Figure 3) is about .4 volts. Many of the pulses show structure at a frequency very close (<2%) to the proton‐cyclotron frequency.