Northwestern astrophysicists and international researchers detected a gravitational-wave signal from a neutron star merger with a likely light black hole 650M ly away, within the mass gap.

Northwestern University astrophysicists and international researchers have detected a gravitational-wave signal caused by the merger of a neutron star and a mystery object, likely a light black hole. The detection occurred 650 million light-years away and falls within the "mass gap" between the heaviest neutron stars and the lightest black holes. This event could help scientists better understand the nature of objects in the mass gap and how they form.