Answer:

The sun appears red at sunrise and sunset because the sun is closer to the horizon during these times of the year. During its journey to our eyes, sunlight passes through a denser layer of air and travels a greater distance than usual. The majority of the blue light is dispersed. Furthermore, we are exposed to the red colour, which causes the sun to appear red at sunrise.

The sun is directly overhead at midday. The sunlight travels a shorter distance before reaching our eyes because it passes through layers of air and covers a lesser distance. As a result, nearly all colours of light are distributed equally. As a result, the sun seems white.