Gravitational waves from the merger of a black hole and a neutron star may have been detected for the first time. That is the claim of scientists working on the LIGO and Virgo observatories, who have reported seeing five possible gravitational-wave signals since the upgraded detectors switched-on on 1 April 2019.
Speaking at a press conference today, representatives of the team said that they were also investigating whether a neutron-star merger was detected in April. If confirmed, this would be the second such event observed by LIGO and Virgo. The three other potential events are of merging pairs of black holes. Electromagnetic radiation was not detected from any of the five potential events.
LIGO first hit the headlines in February 2016, when scientists announced that the two interferometers – each with 4 km-long arms – had made the first-ever detection of gravitational waves. That signal came from the merger of two black holes and since then the observatories – located in Louisiana and the state of Washington – have spotted nine more black-hole mergers.
The Virgo gravitational-wave detector is in Italy and an upgraded version of the observatory joined the hunt in 2017 – just in time to ...