6. Quasars: Beacons of Growth
Among the brightest objects in the universe, quasars are powered by rapidly growing supermassive black holes. Their dazzling luminosity signals periods of intense accretion, when enormous amounts of matter spiral into the black hole’s grasp. Quasars play a key role in shaping early galaxies, driving energetic outflows that regulate star formation and sculpt galactic structure. As detailed by Harvard, studying quasars unlocks clues about the formative years of galaxies and black hole growth across cosmic time.