The International Ultraviolet Explorer (IUE)

The International Ultraviolet Explorer (IUE) was launched into a geosynchronous orbit on 26 January 1978. It is equipped with a 45-cm mirror and spectrographs operating in the far-ultraviolet (1150-2000 A) and the midultraviolet (1900-3200 A) wavelength regions. In a low-dispersion mode, the spectral resolution is some 6-7 A. In a high-dispersion echelle mode, the resolution is about 0.1 Aat the shortest wavelength and about 0.3 A at the longest. It is a collaborative program among NASA, ESA, and the British SERC. The IUE is operated in real time 16 hours a day from NASA Goddard Space Flight Center near Washington, D.C. and 8 hours daily from ESA's Villafranca groundstation near Madrid, Spain. By the end of 1989, 1870 papers, using IUE observations, have been published in referred journals. During the same period, over 1700 different astronomers from all over the world used the IUE for their research.