(Advanced Satellite for Cosmology and Astrophysics, Astro-D)
(1990s Japanese space X-ray telescope)
ASCA (for Advanced Satellite for Cosmology and Astrophysics)
was a space X-ray observatory launched by the Japan Aerospace Exploration Agency (JAXA) in
1993 and observing from 1994 to 2000. It carried four telescopes,
operating simultaneously, two with gas imaging spectrometers (termed
GIS) and two with solid-state imaging spectrometers (termed
SIS) the former with a larger field of view and the latter with a
better spectral resolution. Angular resolution was
on the order of an arcminute.
Among its surveys was the ASCA Galactic Plane Survey (AGPS).