By combining forefront X-ray observations with state-of-the-art supercomputer simulations of the buildup of galaxies over cosmic history, researchers have provided the best modeling to date of the growth of the supermassive black holes found in the centers of galaxies. Using this hybrid approach, a research team led by Penn State astronomers has derived a complete picture of black-hole growth over 12 billion years, from the universe s infancy at around 1.8 billion years old to now at 13.8 billion years old.