Guido Risaliti/NuStar

The best evidence yet that some supermassive black holes (SMBH) rotate at extremely high rates has been found by an international team of astronomers. Made using the recently launched NuStar space telescope, the study suggests that a huge black hole at the centre of a distant galaxy acquired a huge amount of rotational energy as it formed. The discovery could provide important information about how SMBHs and their associated galaxies form and evolve.