Galaxy clusters are collections of hundreds to thousands of galaxies bound together by gravity. Elucidating the internal dynamics of these exceptional structures is key to understanding how they formed, and thus to gaining insights into the matter and energy content of the wider Universe. In a paper in Nature, Audard et al.¹ take a crucial step forwards with the most detailed observations yet of internal motions in the Centaurus cluster of galaxies, which lies approximately 36.8 megaparsecs (120 million light years) from Earth.