Here's how it works:
* Light bends: When light passes through different mediums (like air and space), it bends. This bending is called refraction. The denser the medium, the more the light bends.
* Air density changes: Earth's atmosphere is denser near the ground and less dense higher up. This means that light from the sun bends more when it's near the horizon.
* Apparent position: As the sun is low on the horizon, its light passes through a greater amount of denser air. This causes the light to bend more, making the sun appear slightly higher and larger than it actually is.
In essence, the sun's rays are distorted by the atmosphere, making it look like it's closer and bigger when it's near the horizon.
This illusion also contributes to the sun appearing flattened at sunrise and sunset, as the bottom of the sun is bent more than the top.
