Local time variation of equatorial thermospheric composition determined by the San Marco 3 Nace

Abstract

The results of the Neutral Atmospheric Composition Experiment (Nace) on the Italian San Marco 3 satellite are analyzed. The analysis provides a comprehensive description of the daily variations in the densities of O, N2, Ar, and He in composition of the lower thermosphere, and also indicates that transport processes (possibly occurring elsewhere in the atmosphere) play an important part in the daily variation of the thermospheric composition at altitudes between 220 and 250 km.