An Italian X-ray astronomy mission with participation from the Netherlands and ESA, launched in 1996 April. It was named after the Italian astronomer Giuseppe (‘Beppo’) Paolo Stanislao Occhialini (1907–93); SAX is the acronym for ‘Satellite per Astronomia a raggi X’. The satellite carried a range of instruments for broad-band timing and spectroscopy over the energy range 0.1–300 keV. BeppoSAX made spectroscopic studies of X-ray sources and looked for gamma-ray bursts (GRB), observing the first GRB X-ray afterglow. It ceased operation in 2002 April and re-entered the atmosphere a year later.
http://www.asdc.asi.it/bepposax/ Official mission website.