Preparing IUE's solar array for a thermal-vacuum test at ESTEC. The International Ultraviolet Explorer was launched on 26 January 1978 as a joint ESA/NASA/UK project to study the UV spectra of celestial objects. Operations continued until 30 September 1996 - making it the longest-lived spaceborne astronomy mission - after returning more than 104,000 spectra. [Image Date: 1975] [75.06.407-005]