The accretion of a solar mass per day by a 17-billion solar mass black hole
Nature Astronomy, Published online: 19 February 2024; doi:10.1038/s41550-024-02195-x A black hole at the centre of a quasar at a redshift of z = 4 is accreting the mass of the Sun every day. The quasar’s extreme luminosity is equivalent to 50,000 times