A Japanese X-ray astronomy satellite, known as Astro-D before its launch in 1993 February; also known in Japanese as Asuka. The satellite had four grazing-incidence telescopes each covering the energy range 0.5–12 keV (0.10–2.5 nm). ASCA (Advanced Satellite for Cosmology and Astrophysics) was the first X-ray mission to use CCD spectrometers. It operated until 2000 July and re-entered in 2001 March.

http://heasarc.gsfc.nasa.gov/docs/asca/ Information page at Goddard Space Flight Center.