Black hole quantum effects are usually thought to be too small to have any observable signatures. This is indeed the case for heavy black holes, such as the ones detected via gravitational waves ...
Besides stars, the United States Navy uses quasars as beacons. Quasars are distant galaxies with supermassive black holes, surrounded by ... X-Ray Flashes from a Nearby Supermassive Black Hole ...
"Our measurements imply that the supermassive black hole mass is 10% of the stellar mass in the galaxies we studied." Using the James Webb Space Telescope (JWST), astronomers have discovered ...