Beskrivning : Numbered cover, ESA Command Center seal. Tracking of OTS 2, an experimental satellite inherited by ESA in 1975 from its predecessor, the European Space Research Organization (ESRO). The first of the pair of OTS satellites was lost at launch in September 1977. OTS 2 became one the the first GEO communications satellites to carry six Ku-band (14/11 GHz) transponders and was capable of handling 7,200 telephone circuits.