Black Holes: Gravity's Relentless Pull

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Black Holes: Gravity's Relentless Pull

Can I safely orbit a black hole?

It is possible to be near a black hole without falling into it, provided you move rapidly. This is similar to what happens in the solar system: Earth does not fall into the Sun because we move around it at a speed of some 67 thousand miles per hour. But the orbits near a black hole can have various interesting shapes, whereas those in the solar system are always elliptical (and almost circular).

Suppose that you are near a black hole and launch a spaceship to study it up close. If you start too slow, you will spiral into the black hole. If you start too fast, you will fly into the far off distance. At intermediate speeds you will orbit the black hole in a complicated pattern. There is exactly one launch speed that will put you on a circular orbit. This provides a stable vantage point if you start far from the black hole, but it is like playing Russian roulette if you start too close. In that case, even the smallest movement on your ship will drastically change your orbit. You might drift away from the black hole, but if you are unlucky you will spiral into it.