Interesting how gravity works - even from space.
Indeed. A lot of people think that in zero-g there is no graviation anymore, which is just fundamentally wrong. What is missing just is the counterforce which results in what we call weight. But graviation does not stop above the mesosphere. The graviation always is "active" and keeps the station in earth orbit (and everything as well, and not to mention the massive moon). You constantly "fall" within orbit or space. There is always graviation, if not from the earth you'll get it from the sun or another body. In earth orbit you don't fall vertically (like you also do when you fly to the moon for example), but instead horizontally around the earth. That's the entire myth of weightlessness. It does not happen in space or at a certain place (and remember that mass is location-independent: 1kg on earth remains 1kg in earth orbit or on the surface of the moon as well). It just happens whenever you or somethings falls. Just jump and you'll experience weightlessness everywhere at any time, although it's just a very short moment
Graviation also causes orbits not to be circular, and not even to be properly/100% elliptic. Like airholes, in orbit/space you also have irregularities (speed and altitude variations) due to different earth graviational forces and also correlation with the moon and other bodies. But it's just tiny irregularities that are not really noticeable, well, until you need something to do where graviational effects become noticable: docking.
