This week, Catriona tells us about the brightest-known object in the universe, a quasar 12 billion light years away that’s in fact a supermassive black hole that gobbles an entire sun every day; and we replay Claire’s story about new evidence for another theorised cosmic event, the Moon’s formation through a collision of the early Earth with the Mars-sized protoplanet Theia. Wolf et al. 2024. The accretion of a solar mass per day by a 17-billion solar mass black hole. https://doi.org/10.1038/s41550-024-02195-xQian Yuan et al. 2023. Moon-forming impactor as a source of Earth’s basal mantle anomalies. https://doi.org/10.1038/s41586-023-06589-1