Red Sunset Wallpaper 800 x 600
As sunrise and sunset are calculated from the leading and trailing edges of the Sun, and not the centre, this slightly increases the duration of "day" relative to "night". Further, because the light from the Sun is bent by the atmospheric refraction, the Sun is still seen after it is below the horizon. This effect is a daily illusion along with sunrise. The sun also appears larger on the horizon, which is another optical illusion, similar to the moon illusion.