ELECTRIC-FIELD MEASUREMENTS DURING THE MAC EPSILON CAMPAIGN

As part of the MAC/EPSILON campaign in northern Norway during October and November 1987, five rocket-borne payloads made three-axis electric field measurements of the middle atmosphere. Flights 31.066 and 31.067 consisted of large multi-experiment packages, while the other three flights (30.036, 30.037 and 30.038) were devoted primarily to electrical measurements. Simultaneous measurements of the horizontal electric field made by flights 31.066 and 30.036 were in general agreement in their limited altitude region of overlap. A simultaneous small temporal feature was observed in both datasets. The relatively more extensive horizontal E-field datasets from 31.066 and 31.067 both exhibited a decreasing mapping function with decreasing altitude, which is an indication of the observation of field from a local auroral patch. Small-scale variations in the horizontal fields of the flights were similar to observed wave-like variations in the neutral wind field. No unusual features were observed at high altitudes in the measured E[[ field. Two of the payloads observed small vertical layer structures between 40 and 50 km. No electric field structure was observed in association with the presence of a sudden sodium layer.