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PIP’S STARHAVEN · FIELD NOTES · PARENTS & TEACHERS

Black holes: an extreme boundary

The event horizon is a boundary in spacetime, not a solid surface. Light from outside it can still reach us, including radiation from very hot material near a black hole.

A black hole’s pull at a large distance depends on its mass, just as for other objects. Stable orbits can exist outside it. Not every star becomes a black hole, and the Sun does not have enough mass to end that way.

Wonder about this

Does being near a black hole mean every distant object must fall into it?

A science clue

No. Objects far enough away can orbit; mass, distance, and motion matter.