X-RAY
HEAO A-1 X-ray Source Catalog 1984:
Full sky coverage of 842 X-ray sources detected with the NRL Large Area Sky Survey Experiment on the High Energy Astronomical Obsrvatory 1 satellite. The catalog is considered 90% complete at the 250 mJy level.
Einstein X-Ray Observatory Extended Medium Sensitivity Survey:
835 sources detected by the Einstein X-Ray Observatory). Covers a total area of 778 square degrees of the high galactic latitude sky (|b|>>20). Objects include active galactic nuclei (QSO's, quasars and Seyfert), 51.1%; BL Lacertae objects, 4.3%; clusters of galaxies, 12.2%; normal galaxies, 2.1%; cooling flow galaxies, 0.6%; Galactic stars 25.8%; and unidentified, 3.9.