Can I see the curvature of the earth at the shore or is it my imagination?

Question

Or maybe its another effect, such as optical. I understand that the horizon is proportional to the square root of the height of the observer relative to the sea level . So on the beach, lets say I am 20 feet high. That works out to something like 25 miles. Looking left to right rapidly, its true that the locus of lines from my eye to the horizon would be a cone. But only with a 20 foot drop in 25 miles. I would never see that. Has anyone seen this?

Answer 1

You can infer or measure it, but it's very hard to perceive it visually. That's why the world was considered flat for so long. But it's quite visible from the space shuttle, even at its lowest orbit of around 100 miles. Where is that perception threshold? Is it discernable from an airplane at 7 miles?

Answer 2

Its an optical illusion. You're not nearly high enough to see the curvature.

You're probably getting confused because your can actually see the horizon where earth meets sky at the shore, and that horizon could appear to change position based where you are sitting. But you can't see the curvature. You're simply too small and not high up enough.

Answer 3

Actually you can see the curvature of the Earth. If you have a clear view of about 20 miles ahead of you, the Earth will curve and you cannot see anything beyond that 20 mile marker.
Hope this helps!

Answer 4

I have the impression that I can detect a slight curve when I look at the surface of the Atlantic ocean from a twenty feet high hill.