Author: Matthew J. Hayes, Associate Professor of Astrophysics, Stockholm University

Supermassive black holes are some of the most impressive (and scary) objects in the universe – with masses around one billion times more than that of the Sun. And we know the’ve been around for a long time. In fact, astronomers have detected the extremely luminous compact sources that are located at the centres of galaxies, known as quasars (rapidly growing supermassive black holes), when the universe was less than 1 billion years old. Now our new study, published in Astrophysical Journal Letters, has used observations from the Hubble Space Telescope to show that there were many more (much less…