Exosat

The Exosat satellite was operational from May 1983 until April 1986 and in that time made 1780 observations in the X-ray band of most classes of astronomical object including active galactic nuclei, stellar coronae, cataclysmic variables, white dwarfs, X-ray binaries, clusters of galaxies, and supernova remnants. The payload consisted of three instruments that produced spectra, images and light curves in various energy bands.
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