This handout artist's impression obtained on June 18, 2024 from the European Southern Observatory (ESO) shows two stages in the formation of a disc of gas and dust around the massive black hole at the centre of the galaxy SDSS1335+0728. In late 2019, the galaxy SDSS1335+0728 suddenly started shining brighter than ever before and was classified as having an active galactic nucleus, powered by a massive black hole in the galaxy's core. This is the first time the awakening of a massive black hole has been observed in real time. (Photo by ESO/M. Kornmesser / European Southern Observatory / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / European Southern Observatory / ESO/M. Kornmesser " - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS (Photo by ESO/M. KORNMESSER/European Southern Observatory/AFP via Getty Images)