'A new way to study the edge of a black hole': Physicists just got the closest-ever look at a black hole's event horizon

Scientists have detected a new type of gravitational wave signal from a black hole merger that may carry information from the very edge of a black hole's event horizon. By analyzing a strong gravitational wave event from January 2025, researchers identified a "direct wave" — a faint but distinct signal shaped by the region just outside the point of no return — opening a potential new way to study one of the universe's most extreme environments.