Here's why:
* The Earth is curved: Because of the Earth's curvature, the horizon is actually below eye level for most observers.
* Perspective: Our eyes perceive the horizon as a flat line, but it's actually curved along with the Earth.
* Height: The higher you are, the further away the horizon appears, and the lower it will be relative to your eye level. If you were on a mountaintop, the horizon would be significantly below your eyes.
* Atmospheric effects: The atmosphere can also make the horizon appear slightly higher than it actually is due to refraction (bending of light).
So, why does it *feel* like the horizon is always at eye level?
This is a trick of our brains! We are used to seeing the world in a flat, two-dimensional perspective. Our brains instinctively flatten out the curved surface of the Earth, making the horizon seem to be at eye level.
Here's an experiment to prove it:
1. Stand up and look at the horizon.
2. Now, bend down and look again. The horizon will appear lower.
3. Next, climb onto a chair or something that raises you up. The horizon will appear higher.
This experiment shows that the horizon's position changes relative to your eye level, and it's not always at the same point.
