Why does the sun appear red at sunrise and sunset?
Answer: Sunlight is scattered by dust particles floating in the atmosphere. As we know, the longer the wavelength of the light, the less the diffraction. Of the seven colours of sunlight, red has the longest wavelength; So the red light rays are less deflected. The sun is near the horizon during sunrise and sunset. As a result, light from the sun has to travel much longer through the atmosphere. During this long journey, the rays of other colours except red are deflected more, so the lights of those colours go in the other direction. Only red light reaches our eyes in greater quantities. So the sun appears red at sunrise and sunset.