Interstellar matter research with the Copernicus satellite

Abstract

The use of the Copernicus satellite in an investigation of interstellar matter makes it possible to study absorption lines in the ultraviolet range which cannot be observed on the ground because of atmospheric absorption effects. A brief description is given of the satellite and the instrument used in the reported studies of interstellar matter. The results of the studies are discussed, giving attention to interstellar molecular hydrogen, the chemical composition of the interstellar gas, the coronal gas between the stars, and the interstellar abundance ratio of deuterium to hydrogen.