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Name: N Grey
Status: N/A
Age: N/A
Location: N/A
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Date: Around 1999

What is a 'black hole'?

It is a phenomenon that comes out of general relativity. If a mass, like a star, can be squeezed down into a small enough size then there is a radius below which an amazing thing happens. If the mass is all squeezed into this small size (for the earth mass the size is about the size of a basketball) then it turns out that the gravity is so strong that nothing, no light, or anything can every escape outside of this radius. Since no light can escape, physicists have called it a "black Hole" partly because that's what it would look like if you could see it. We think that very massive stars can collapse under their own "weight" down into a small enough size to be inside their Schwartzchild radius ( the special radius I mentioned above). After they collapse then they continue to suck other near by matter into the space so black holes continue to get more massive as time passes. IT is now believed that the center of most galaxies must have a black hole there. Recently several scientists have thought they measured a black hole. The book called the History of Time by ...I can't remember this famous person ... Hawkins, Steven .... really explains this well, but it is a hard read if you have not had some mathematics and physics. On the other hand trying to read it can give a glimpse of some beautiful astro physics. Good luck.

Sam B

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