Why are sunsets red

A sunset is one of the most beautiful natural phenomenons that exist on earth, and everybody has seen it at some point in their lives. While watching a sunset, many might wonder though, about why sometimes sunsets are red or orange. The reason lays in the fact that sunlight or “white light” as we call it, actually contains all colors. The position of the sun in the sky determines the color of the sky, which is why when the sun is on its journey from a low position, the shorter wavelengths of color, mainly blue is visible. The colors of longer wavelength like yellow, orange and red are visible clearly during the sunset. The distant position of the sun during a sunset makes it impossible for the shorter, color wavelengths like blue or green to reach the surface as they become scattered and thus only the longer wavelengths of color, namely red and orange reaches the earth’s surface. The sun and the surrounding sky therefore appears red to our eyes during the sunset.

A theory stating the reason behind red sunsets explain that the increased amount of red light seen from the earth’s surface is due to the presence of aerosols in the lower portion of our atmosphere. Aerosols reflect the red and the orange in the sunlight. The same red effect is not seen during the entire day in spite of the aerosol’s presence because the sun’s rays pass through a much longer aerosol filled path during sunsets because of the position of the sun, than during the day when the sun is positioned above head.

Aerosols are tiny particles of both manmade and natural matter found suspended in the earth’s lower atmosphere. They are found to be quite vital in cloud formation and are not seen purely as pollutants anymore. Aerosols are a mixture of soil, sea-salt, ash, dust particles, sand and a host of other solid and liquid substances.