Mysterious origins of Universe’s biggest black holes

The mysterious origins of Universe's biggest black holes Most observations of this type rely on ground-based telescopes that use a technology called "adaptive optics". Observers analyse a bright star (or human-generated laser beam) to measure atmospheric distortions that would otherwise reduce image quality. Computer controlled signals correct for these distortions through tiny adjustments to the physical shape of the telescope's mirror. The results are precise observations of the hearts of galaxies billions of light years away, and a wealth of data on their supermassive black holes. Neumayer was one of the first scientists to use adaptive optics to study galactic cores. "It was just mind-blowing that you could have better resolution from the Earth than from the Hubble Space Telescope," she says. "I worked on measuring specific black hole masses. There is a tight correlation: the more mass a galaxy has, the more massive its central supermassive black hole is. Somehow these objects grow in step." Despite this correlation, there's no clear evidence that massive galaxies create massive black holes, or vice versa. They are connected, but the nature of that connection remains a mystery. One piece of the explanation might involve collisions between galaxies. Most of the observable Universe's two trillion galaxies are accelerating away from one another, but many collisions occur, creating opportunities for two very large central black holes to merge into something even bigger. Some scientists believe this could be how the truly monstrous supermassive black holes are formed. When comparatively tiny stellar black holes collide, they release huge amounts of energy for a fraction of a second, producing a flash so bright that it briefly outshines everything else in the sky. If we were to see a similar event involving supermassive black holes, it would be one of the most cataclysmic events to be detected in the night's sky. But, while scientists suspect mergers between supermassive black holes do occur, they may be made less common due to another problematic aspect of black hole dynamics. Black holes on a collision course spin around one another with increasing speed as they draw closer. But very large black holes reach a point at about one parsec (3.26 light years) apart where their orbital velocity starts to balance out gravitational attraction. The decay of their orbits would happen so slowly that the actual merger could not happen within the current age of the Universe.