AXAF and beyond - The long range future of X-ray astronomy

The Advanced X-ray Astrophysics Facility (AXAF) is a proposed long-lived orbiting national observatory comparable to the Space Telescope, scaled to fit within the cargo hold of the Space Shuttle. The AXAF configuration incorporates a nested grazing incidence mirror assembly and three optical telescopes for the spacecraft's attitude determination and control system. The AXAF concept is compared with the X-ray Timing Explorer and Large Area Modular Array of Reflectors concepts. It is shown that the AXAF system will achieve a hundredfold increase in sensitivity over current X-ray astronomy spaceborne instruments.