Middle atmosphere measurements of small-scale electron density irregularities and ion properties during the MAC/Epsilon Campaign

Abstract

Rocket payloads designed to measure small-scale electron density irregularities and ion properties in the middle atmosphere were flown with each of the three main salvos of the MAC/Epsilon Campaign conducted at the Andøya Rocket Range, Norway, during October to November 1987. Fixed-bias, hemispheric nose tip probes measured small-scale electron density irregularities, indicative of neutral air turbulence, during the rocket's ascent; and subsequently, parachute-borne Gerdien condensers measured the region's polar electrical conductivity, ion mobility and density. One rocket was launched during daylight (15 October, 1052:20 UT), and the other two launches occurred at night (21 October, 2134 UT; 12 November, 0021:40 UT) under moderately disturbed conditions which enhanced the detection and measurement of turbulence structures. A preliminary analysis of the data indicates the presence of small-scale electron density irregularities in the general altitude range of 60 to 90 km. Ongoing data reduction will determine turbulence parameters and also the region's electrical properties below 90 km.