Oh, I did not know that this 'last mile' often makes the difference between collisions and close approaches! Interesting. Indeed, I have to remember that atmosp

Oh, I did not know that this 'last mile' often makes the difference between collisions and close approaches! Interesting. Indeed, I have to remember that atmosphere is a scale and not a hard boundary. Like, I kinda know that, but just how far up there are still particles that are of significance...