Multiple images of a distant quasar are visible in this undated combined view from NASAís Chandra X-ray Observatory and the Hubble Space Telescope. For the first time, scientists have measured the spin of a distant supermassive black hole and found that its rate of rotation is about 3.5 trillion mph – roughly half the speed of light. The finding provides insights into how the black hole and its host galaxy formed. (Photo by Reuters/NASA)
