  Significant advances in science inevitably occur when the state of the art in
instrumentation improves. NASA's newest Great Observatory, the Chandra X-Ray
Observatory (CXO) -- formally known as the Advanced X-Ray Astrophysics Facility
(AXAF) -- launched on July 23, 1999 and represents such an advance. The CXO is
designed to study the x-ray emission from all categories of astronomical
objects from normal stars to quasars.
