The final dance of mixed neutron star-black hole pairs

Artist's view of a black hole-neutron star merger. Carl Knox, OzGrav - Swinburne University Gravitational wave detectors have observed a new type of cataclysmic event in the cosmos: the merger of a neutron star with a black hole. The phenomenon was detected twice in January 2020. Several hypotheses could explain the existence of such mixed pairs. Further observations will be needed in order to settle the question. Another missing piece has just been added to our knowledge of cosmic phenomena. The LIGO, Virgo and KAGRA collaborations have announced the first detection of gravitational waves 1 resulting from the 'mixed' merger between a black hole and a neutron star 2 .