Black Hole
A region of spacetime where gravity is so strong that nothing — not even light — can escape. Formed when massive stars collapse at the end of their lives.
A black hole is a region of spacetime where gravity becomes so intense that nothing — not even light — can escape once it crosses the event horizon. Black holes form when massive stars (typically more than 20 solar masses) exhaust their fuel and collapse under their own gravity.
In Einstein's general relativity, a black hole is fully described by just three properties: mass, electric charge, and angular momentum (spin). At the centre lies a singularity, where current physics predicts infinite density — though this is widely believed to indicate that general relativity breaks down at extreme scales.
The first direct image of a black hole was captured in 2019 by the Event Horizon Telescope, showing the supermassive black hole at the centre of galaxy M87. The black hole at the centre of our own Milky Way, Sagittarius A*, was imaged in 2022.