The X-ray Astronomy Satellite ASTRO-C

The Astro-C satellite, which is due for launch in 1987 and which is designed to investigate the time variability of galactic and extragalactic compact X-ray sources in the 1.5-30 keV energy range, is described. The large-area low-background proportional counter has a 45 sq cm total effective area, and it can detect a 0.1 mCrab source in about 10 minutes. The all-sky X-ray monitor, with a 400 sq cm total effective area, can determine source position with an accuracy of better than 1 x 1 deg. The high time-resolution gamma-ray burst detector can detect bursts as small as 0.000003 erg/sq cm sec.