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Orbit is unintuitive. Objects in orbit are not just floating up there. They are constantly falling under the influence of gravity, just as objects here on Earth. The reason they don't hit the Earth when they fall is that they are traveling sideways at 25,000+ km/h. This is so fast that they miss hitting the Earth, and simply fall forever.

When a rocket launches to orbit, it only goes up a little bit, just to get out of the atmosphere, and then spends most of its time/fuel on going sideways to reach orbital velocity. If you watch a rocket launch you can see that the rocket starts to tip over and go sideways soon after leaving the pad. This is also why launching from a plane doesn't help you very much, because going up is the easy part of getting to orbit. A plane can't help you with the hard part of getting to 25,000 km/h sideways.

For an object in orbit to stop missing the Earth as it falls, it must slow down that sideways velocity, and gravity doesn't help with that.



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