Early Universe Witnesses Merger of Two Supermassive Black Holes.

Astronomers have discovered two quasars lighting up the mutual heart of colliding galaxies during a period in the universe's early history known as "cosmic noon." The energetic quasars are powered by feeding supermassive black holes and are seen as they were just three billion years after the Big Bang, during a period of intense galactic growth and star formation. Such a closely bound pair of energetic quasars are characteristic of merging galaxies, which go on to form massive elliptical galaxies. By investigating such events, astronomers can learn more about the evolution of galaxies and how the universe took the shape we see today.