Supermassive black holes halt rapid construction in an ancient celestial city

Galaxy clusters -- the big cities of the universe -- are home to many giant elliptical galaxies that have completed their growth and are not forming stars. However, it is still unclear what has shut down star formation. In a new study, researchers utilized the James Webb Space Telescope to observe an ancestor of galaxy clusters, revealing the role of supermassive black holes in slowing star formation and allowing them to evolve into giant elliptical galaxies.