Environment of a Black Hole
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Transcript: Contrary to common belief, black holes are not vacuum cleaners that suck up everything in sight. If the Sun were instantly replaced by a black hole of the same mass, life on Earth would of course die because there would be no energy coming from the star, but the orbit of the Earth would continue essentially uninterrupted. A parsec away from a black hole the mass of the Sun, the escape velocity is a mere 94 meters per second. Forty AU away from such a black hole, the escape velocity is four kilometers per second. At the Earth’s orbit distance, one AU, the escape velocity is forty-two kilometers per second. At a distance of the Earth radius from the black hole, 6,300 kilometers, the escape velocity rises to 6,500 kilometers per second. But all the extreme effects of General Relativity on time and space occur relatively close to the event horizon. Within 1.5 Schwarzschild radii, 4.5 kilometers, the distance called the photon sphere, half the light is trapped, and at the event horizon, 1 Schwarzschild radius or 3 kilometers, all light and radiation is trapped.
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