Solved cryptogram

A black hole's edge is not a surface. It is the boundary past which nothing can ever turn back.

Astronomy Facts, sourced to NASA.

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What it means

The event horizon is a place where the geometry of space and time has tipped over, so that every possible path leads inward. Crossing it, an astronaut would notice nothing special at the moment of passage, at least for a sufficiently large hole. It is not a wall and there is nothing there to touch. What is there is a one way condition on the future.

The claim comes from NASA.

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