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How Do Scientists Know What the Inside of a Black Hole Looks Like?
An Elementry View of What We Do and Don’t Know About Black Holes
I asked my 10-year-old son, “What do you think is inside a black hole?”
“Nothing,” he said. “Just the void of space and time.”
When I asked how he knew this, he said that he just guessed.
“Are you sure you didn’t learn this on YouTube or something?”
“No, I just guessed,” he said — there was a slight tension to his voice.
Clearly, my 10 second inquisition about one of the biggest secrets of the universe annoyed him.
While scientists have never been able to directly observe the interior of a black hole, they have been able to infer its structure by studying the way that matter and energy interact with it.
One of the most important pieces of evidence comes from the way that light behaves as it enters a black hole.
As light approaches the event horizon — or point of no return — it becomes stretched out and distorted. This effect, known as gravitational lensing, allows scientists to map the contours of the black hole’s interior.
In addition, scientists have also been able to track the motion of stars that orbit around black holes.
