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Name: Abdul C.
Status: other
Age: 60s
Location: N/A
Country: N/A
Date: Thursday, June 06, 2002


Question:
It is known that nothing can escape the event horizon of a black hole even light. How gravity can escape the event horizon and affects the space surrounding the event horizon?


Replies:
Abdul,

Gravity can escape the event horizon because it is gravity that holds everything in. Gravity pulls on everything, giving everything, even light. But gravity is the weakest force in the universe. In most cases, things are not affected much by gravity. A black hole, however, exerts a very large gravitational force on the universe. An average star can hold a slow-moving planet in orbit forever. A black hole can hold objects traveling at the speed of light in orbit. The event horizon is the distance at which the black hole can no longer pull hard enough to keep an object moving as fast as the speed of light. It can keep slower things in orbit, but not light. As you go further out, the gravitational pull gets weaker and weaker. A black hole is just a super-massive, super-strong star. We cannot know for a fact what happens inside a black hole because we have know way to explore it. It might be very similar to a solar system with even light being held in orbits. It might be something very different. Until we can find some way to measure inside a black hole, everything is just theories based on a few observations and the opinions of scientists.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College



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