This Massive Black Hole Is Mysteriously Quiet, And Astronomers Don’t Know Why
“Messier 51, the Whirlpool Galaxy, is one of astronomy’s most spectacular objects. This enormous, face-on galaxy was the first one ever to reveal its spiral structure. The small object alongside it, the galaxy NGC 5195, is interacting and merging with the Whirlpool galaxy. Such mergers trigger new waves of star formation, create grand spiral arms, and activate supermassive black holes.”
That’s the theory, at any rate. Yet when we look at Messier 51, located just outside of the Big Dipper in the night sky, we find that the X-rays being emitted from it are spectacularly minimal. After the Chandra X-ray telescope made its observations, we simply assumed the higher-energy X-rays would make up for the missing radiation, but they show an extreme shortage as well, with neutron stars on the outskirts outshining them.