or the first time, the mass of a binary pulsar pair has been precisely measured, but it was a race against time before the extreme gravitational warping of spacetime caused one of the dense objects to blip out of view.

Pulsars are rapidly-spinning neutron stars that generate powerful beams of radiation from their poles. Neutron stars are the stellar husks of long-dead stars that ran out of hydrogen fuel and collapsed under gravity to create a mass of degenerate matter.