A Japanese X-ray astronomy satellite, known as Astro-C before its launch in 1987 February. It carried an exceptionally large array (0.4 m2) of proportional counters provided by the UK, covering the energy range 1.5–37 keV (0.034–0.83 nm). An X-ray all-sky monitor and US gamma-ray burst detector were also carried. Ginga operated until late 1990 and re-entered in 1991 November.
http://heasarc.gsfc.nasa.gov/docs/ginga/ginga.html Information page at Goddard Space Flight Center.