Neutral air density and temperature measurements by the TOTAL instrument aboard the ROSE payloads

Four ROSE payloads, launched from November 1988 to February 1989 from northern Scandinavia, carried ionization gauges (‘TOTAL’ instruments) for neutral air density measurements in the altitude range 90–105 km. Temperature profiles are derived by integrating the number density profiles. Density and temperature data are presented. The limitations of the measurement technique as well as instrumental errors are discussed. In one of the flights (F1) a significant temperature enhancement was observed at an altitude where plasma instabilities were detected by independent measurements.