Daily read: Black hole
Black hole
Wikipedia featured article
This article explains one of physics' most mind-bending phenomena in accessible terms—how gravity can become so extreme that it warps spacetime itself and traps light forever—which fundamentally challenges how we understand the universe. It's a featured Wikipedia article, meaning it's been rigorously fact-checked and synthesizes the current scientific consensus on black holes, making it reliable background for understanding recent discoveries like gravitational waves and the first photographed black hole shadow.
A black hole is an astronomical body so compact that its gravity prevents anything, including light, from escaping. Albert Einstein's theory of general relativity, which describes gravitation as the curvature of spacetime, predicts that any sufficiently compact mass will form a black hole. The boundary of no escape is called the event horizon. In general relativity, crossing a black hole's event horizon traps an object inside but produces no locally detectable change. General relativity also predicts that every black hole should have a central singularity, where the curvature of spacetime is infinite.