Black Holes 2

Part I of Essay
What are black holes? Black holes are the remains of a massive star that has collapsed and shrunk to a tiny point in space. They have all of the gravity of the star concentrated into a miniscule point many times smaller than the original. Black holes are difficult to see ....

Part II of Essay
.... would require a velocity greater than the speed of light. No object can reach the speed of light. The distance from the black hole at which the escape velocity is just equal to the speed of light is called the event horizon. Anything, including light, that passes across the event horizon toward the black hole is forever trapped. Using a small black marble as an example to represent the size that the Earth would become if it collapsed and became a black hole, Todd R. Lauer, of the National Optical Astronomy Observatories said, " Black hole ....