The Universe

Black Holes

What happens when a black hole spins?

When a black hole rotates, the shape and structure of the event horizon can change. If a black hole is not rotating, then the event horizon is a perfect sphere centered on its singularity. As a black hole spins, the event horizon flattens into a sort of thick doughnut shape, and a structure called the ergosphere can develop. Here, light beams do not escape the black hole but instead orbit around the singularity.


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