Gravitational waves from the merger of two neutron stars were observed by the LIGO Livingston detector on 25 April 2019 – according to an international team of astrophysicists in the LIGO and Virgo collaborations. This is the second time that a signal from such an event has been seen and the merger is puzzling astrophysicists because it appears to have created an object with “unusually high mass”.
In a paper that has been submitted to The Astrophysical Journal Letters, the researchers say that the merger occurred about 500 million light-years away. The above video is a simulation of the merger process and the gravitational waves it produced.
The signal (dubbed GW 190425) was not recorded by the LIGO Hanford detector, which was not operating at the time, nor was it detected by the Virgo detector.
A recent preprint from an independent team of astronomers in Russia suggests that two gamma-ray pulses were also emitted during the April 2019 merger.
LIGO comprises two 4 km long interferometers in the US – one in Livingston, Louisiana and the other in Hanford, Washington. The Virgo interferometer stretches over 3 km in the Italian countryside near Pisa. In August 2017 ...