A collaboration of researchers including UBC scientists have observed gravitational waves from the collision of what is most likely a neutron star and an object likely to be a light black hole, 650 million light-years from Earth.

The mass of the black hole is 2.5 to 4.5 times the mass of Earth’s sun, meaning it falls in the so-called ‘mass gap’: heavier than heaviest known and theorized neutron stars but lighter than the lightest black holes in our galaxy.

The collision, reported in a preprint paper, was detected by one part of an international network of gravitational wave detectors, comprised of the Laser Interferometer Gravitational-Wave Observatory (LIGO), the Virgo Gravitational Wave Interferometer, and the Kamioka Gravitational Wave Detector (KAGRA).

“This detection, the first of our exciting results from the fourth LIGO-Virgo-KAGRA observing run, reveals that there may be a higher rate of similar collisions between neutron stars and low mass black holes than we previously thought,” says Dr. Jess McIver, assistant professor at UBC and deputy spokesperson of the LIGO scientific collaboration.