ESA Science & Technology - Cos-B
Cos-B was ESA's first satellite dedicated to a single experiment. Its scientific mission was to study in detail the sources of extra-terrestrial gamma radiation at energies above about 30 MeV. The originally foreseen duration of the mission was two years, but in fact Cos-B functioned successfully for 6 years and 8 months. During this time an extensive survey of the Galaxy was made in the energy range 50 MeV to 5 GeV.