Measurements of the thermospheric meridional wind from the S85‐1 spacecraft

Abstract

The upper atmosphere composition spectrometer (UACS) was flown on the Department of Defense Space Test Program mission S85‐1. UACS was designed to measure neutral composition, temperature, and the in‐track wind component in the lower thermosphere. In the high inclination orbit of S85‐1, UACS measured the meridional component of wind at all but the highest latitudes. While techniques to measure cross‐track neutral wind have been successfully demonstrated by other investigators, in situ measurements of the in‐track wind component have not been published before. UACS obtained a small but significant set of wind data for 2 days in July 1984 at altitudes between 200 and 235 km, at local solar times of 1030 and 2230 hours. The measured winds compare favorably with published results from ground‐based incoherent scatter radar and Fabry‐Perot interferometer experiments and with satellite‐based cross‐track measurements of the meridional wind.