Hubble found a narrow ribbon of stars apparently stripped from a globular cluster in a galaxy 115 million light-years away—the first evidence of such a stream beyond the Milky Way, opening a new way to map dark matter in distant galaxies.
A narrow ribbon next to an ultra-diffuse galaxy has become the strongest evidence yet for a globular cluster stellar stream beyond the Milky Way. The feature appears in deep Hubble images of UGC 9050-Dw1, a faint galaxy about 115 million light-years away, and extends from a compact object that is likely the cluster that is … Read more