Eli5: why does the sun appear a bit flattened while the sunset is happening ?

Question

Eli5: why does the sun appear a bit flattened while the sunset is happening ?

In: Physics

Answer 1

Light refraction. The sun’s light “bends” as it passes through the atmosphere at an angle. Near sunrise and sunset, this makes the sun appear a bit higher above the horizon than it actually is. Because light from the “bottom” of the sun is hitting the atmosphere at a shallower angle than light from the “top” that part of the sun appears a bit more elevated, giving the sun a slightly flattened appearance.