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Contrary to popular myth, a black hole is not a cosmic vacuum cleaner. In other words, a one-solar-mass black hole is no better than any other one-solar-mass object (such as, for example, the Sun) at "sucking in" distant objects. However, a one-solar-mass black hole has the same amount of matter as any other one-solar-mass object but compressed into a much smaller space, making it impossible to move fast enough to leave a black hole once there.  If a spaceship could land on a black hole, it would never be able to take off again.

Contrary to popular myth, a black hole is not a cosmic vacuum cleaner. In other words, a one-solar-mass black hole is no better than any other one-solar-mass object (such as, for example, the Sun) at "sucking in" distant objects. However, a one-solar-mass black hole has the same amount of matter as any other one-solar-mass object but compressed into a much smaller space, making it impossible to move fast enough to leave a black hole once there.  If a spaceship could land on a black hole, it would never be able to take off again.

The term "black hole" is also used as a metaphor for a place that it is hard to get out of, generally containing a high concentration of something unpleasant.  Ex: "The inner city is a black hole of crime and drug use." Note that the Black Hole of Calcutta is ''not'' a reference to the celestial object; the name of the place predates the discovery of black holes in space and the Black Hole of Calcutta was a horrible underground prison in Calcutta, India.

The term "black hole" is also used as a metaphor for a place that it is hard to get out of, generally containing a high concentration of something unpleasant.  Ex: "The inner city is a black hole of crime and drug use." Note that the Black Hole of Calcutta is ''not'' a reference to the celestial object; the name of the place predates the discovery of black holes in space and the Black Hole of Calcutta was a horrible underground prison in [[Calcutta]], India.

{{Relativity}}

{{Relativity}}