Ultraviolet spectra obtained by the Hubble Space Telescope have confirmed that a pair of stars in the Milky Way galaxy are in fact one binary star. A research team at the University of Washington used a faint object spectrograph to detect a powerful x-ray source and a previously observed ultraviolet radiation source, revealing that a dead white-dwarf star orbiting a more exotic neutron star constitutes one binary system. Previously, scientists recorded 11-min changes in x-ray emission from the binary, corresponding to one orbit of the binary pair, and predicted corresponding variations in ultraviolet light.