An international team of astronomers have used the NASA/ESA/CSA James Webb Space Telescope to find evidence for an ongoing merger of two galaxies and their massive black holes when the Universe was only 740-million years old.
However, scientists still don’t fully understand how these objects grew to become so massive. The finding of gargantuan black holes already in place in the first billion years after the Big Bang indicates that such growth must have happened very rapidly, and very early. Massive black holes that are actively accreting matter have distinctive spectrographic features that allow astronomers to identify them. For very distant galaxies, like those in this study, these signatures are inaccessible from the ground and can only be seen with Webb.
“The mass of the other black hole is likely similar, although it is much harder to measure because this second black hole is buried in dense gas,” says team member Roberto Maiolino of the University of Cambridge and University College London in the UK.