Gravitational waves from the merger of a black hole and a neutron star may have been spotted for the first time by the LIGO and Virgo detectors. The signal was detected on 14 August and appears to come from an event that occurred about 900 million light-years away.
The detection has been logged on the Gravitational-Wave Candidate Event Database, where the LIGO–Virgo team say that there is a greater than 99% probability that the source of the gravitational waves are from a black-hole–neutron-star merger. It is likely that the larger object was heavier than five solar masses and the smaller object lighter than three solar masses.
There is no indication so far that any electromagnetic observations of the object have been made by any other telescopes. This will come as a disappointment to the astronomy community because “multimessenger” observations across the electromagnetic spectrum could provide important insights into black holes, neutron stars and how they merge. So far, the only multimessenger observations to involve gravitational waves were made in 2017 when LIGO–Virgo spotted a signal from the merger of two neutron stars.
A new cosmic messenger