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Have to hold multiple concepts in head at the same time.

If you're "far away" with gravitational potential energy and get "close" to the atmosphere that potential will have to go somewhere and it'll go into speed. Its like how, without a parachute on earth, falling 40 M means about 100 KM/h impact speed. And parachutes don't work outside the atmosphere so its retrorockets or hit pretty fast. Going from up there to down here means a certain velocity on the fall in.

Conceptually there is a calculatable difference between the speed "from infinity if the earth were not orbiting the sun" vs "from entering the earth's sphere of influence where the earth gravity matters more than the sun's gravity" but it turns out not to matter much. You're probably going to be coming in very fast from falling into the sun's gravity well. But even if the stars align and you hit the earth's influence at zero m/s (LOL good luck) you'll still hit the atmosphere "around escape velocity" after some rounding.




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