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Black Hole Reality

StarDate: 
July 26, 2017

Black holes are among the most popular objects in the universe. But they’re also among the most misunderstood. Among many misconceptions, they’re not as voracious as they’re often portrayed.

A black hole is an object with such powerful gravity that nothing can escape from it, including light. Some were born from the collapse of supergiant stars, and are several times as massive as the Sun. Millions of these objects may speckle the Milky Way galaxy.

When a star becomes a black hole, though, it doesn’t automatically suck up all the planets and other objects around it.

If the Sun were to become a black hole, for example — something that’s not possible, by the way — Earth and the other planets wouldn’t “feel” anything different. Even though the black-hole Sun would be just a few miles in diameter, Earth would continue to orbit at the same speed and distance as it does today. So would Mars and Jupiter and Halley’s Comet.

The point is that while the Sun’s size and energy output would change dramatically, its mass would remain the same, and it’s mass that determines an object’s gravitational pull, not its size.

Objects that got too close to the black hole would be torn apart, and their remains would form a hot disk. As this material spiraled into the black hole, it would get extremely hot, so it would glow brightly. Beyond that close range, though, the rest of the solar system would go on as before — undisturbed by the nearby black hole.

 

Script by Damond Benningfield

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