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## Main Question or Discussion Point

Black holes irresistibly suck things in. That is a common misconception in science fiction. In fact, a spherical black hole of mass M attracts exterior mass no more strongly than a spherical star of mass M. Their exterior spacetimes are the same Schwarzschild geometry. But there is a sense in which it is more difficult to escape from close to a black hole than from a Newtonian center of acctraction of the same mass. Imagine using the thrust of a rocket to hover at a constant Schwarzschild coordinate radius R outside a spherical black hole of mass M. How much thrust would the rocket of mass m need to exert? Would it be infinitely larger as the radius R approaches 2M?

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