Black holes of ’all shapes and sizes’ in new gravitational wave catalogue

Credit: Carl Knox, OzGrav/Swinburne - The largest catalogue of gravitational wave events ever assembled has been released today, with dozens of ripples in space time captured by a global network of detectors. The aftershocks of huge astronomical events, including rare mergers of neutron stars and black holes, were picked up by an international team of scientists, include experts from Cardiff University's Gravity Exploration Institute. A total of 35 new gravitational wave events have been detailed in today's paper, published in XX, bringing the total number of observed events to 90 since the first detection was made in 2015. The catalogue documents detections made between November 2019 and March 2020, using the two Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors in Louisiana and Washington state in the US, and the Advanced Virgo detector in Italy. Of the 35 events detected, 32 of those were most likely to be black hole mergers - two black holes spiralling around each other and finally joining together, an event which emits a burst of gravitational waves. Two of the 35 events spotted were likely to be neutron stars and black holes merging - a much rarer event, and one that was only discovered in the most recent observing run of LIGO and Virgo. Of these rare neutron star and black hole mergers, one event seems to show a massive black hole (about 33 times the mass of our Sun) with a very low-mass neutron star (about 1.17 times the mass of our Sun).