evidenceobservational
The event horizon is the boundary around a black hole beyond which nothing can escape.
30% confidence
A black hole’s gravity is so strong that it creates a point of no return — the event horizon. If anything crosses this boundary, whether it’s light, gas, or a spaceship, it can’t get back out. That’s why black holes seem invisible and why they are called 'black.' The event horizon marks the edge of the black hole’s influence.
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