At the heart of almost every galaxy, including our own, is a monstrously large black hole with mass millions or billions of times that of the sun. These supermassive black holes are generally lonely ...

Take a journey to 89 million light-years away from Earth to the NGC 7727 galaxy. It harbors the closest pair of supermassive black holes discovered yet. Credit: ESO/L. Calçada ; N. Risinger (skysurvey ...