What % of the sky can i see?

[dkatwa]

Can't find answer on Google...
I was wondering, as an average 5'8" man, if I was in the middle of the sea (calm conditions, so I can see the horizon in all directions), what % of the sky can I see? OK, ignore the fact that I can't stand in the middle of the sea, but you get the picture?
My brain does not allow me to even attempt a useful answer...hence, why the brains on this site can surely answer this?
cheers

[dkatwa]

This is doing my head in...I mean, if we can see 50% of the sky, then by the time a plane is over the horizon, perhaps in 5 mins, it would be seen over the horizon by someone standing on the other side of the Earth...so that does not make sense to me.


Maybe if I elaborated a bit...imagine the Earth was at the centre of the Sun..so we would see an area of x sq Km on the 'surface' of the Sun....so this would be y% of the total area of the Sun...now, from what I know of maths (CSE grade D and A level grade E!!), is that if there was a bigger sphere put there instead of the Sun, then the ratio would not change i.e. we would still see the same % of the area of the sphere...


Dunno if the question makes sense....head hurts just thinking about it