When the air is clear, the sunset will appear yellow, because the light 1 the sun has passed a long distance 2 air, and the blue light has been scattered away. If the air is polluted 3 small particles, natural or otherwise, the sunset will be more red. Sunsets 4 the sea may also be orange, due to salt particles in the air. The sky 5 the sun is seen reddened, as well as the light coming directly from the sun. This is because all light is scattered relatively well through small angles, but blue light is then more likely to be scattered twice over the greater distances, leaving the yellow, red and orange colors.