Broad Band X-ray Telescope
The Broad Band X-ray Telescope was flown on the Space Shuttle Columbia from December 2 through December 11, 1990 as part of the ASTRO-1 payload. The flight of BBXRT marked the first opportunity for performing X-ray observations over a broad energy range with a moderate energy resolution.
BBXRT was co-mounted with three ultraviolet telescopes HUT, WUPPE, and HIT for Astro-1 in 1990.
This was, "..the first focusing X-ray telescope operating over a broad energy range 0.3-12 keV with a moderate energy resolution." according to NASA.