Perception relative to gravity?
I was discussing in another forum the idea of one's perception relative to gravity. It is know that a person standing on the South Pole would not feel "upside down" due to gravity and perception. The Earth is too large to be viewed as a sphere...and gravity gives us a natural sense of up and down...with down always being towards the ground.
The debate is how tall must a person be to realize that he/she IS upside down. If a person was so tall that his head reached the upper stratosphere, would he have a sense of being "upside down" if standing at the south pole. If not, let's say that his height reached into the mesosphere, thermosphere, or exosphere...he could see the curvature of the Earth at any of those levels. Would he begin feeling that he is "upside down"? If not, what if his height grew to where his feet covered the entire soutern hemisphere...and his head soured halfway to the moon? Place another man at the North Pole with an equivalent height...and they would see each other from space. One man would look upside down from the point of view of the other.
In essence, it was being argued that even at such vast heights, a person would still not have a sense of being "upside down". If that was the case, you'd have to argue the way astronauts in space see the Earth. If they could identify individual humans at that height, the majority of them would appear sideways, being closer to the Equator. If the astronauts could see scientists in Anarctica, they would appear upside down to an astronaut in space. With that said, I believe that it is obvious that height can counter gravity's perception...only if the height is at a magnitude where you can see the curvature of the Earth.