Dramatic Sunset

Sunset

It was the most amazing sunset tonight. The sun broke through the upper cloud layer above then set beneath the horizon below.

Have you ever wondered why sunsets are red?

It's the same reason the sky is blue: Rayleigh scattering.

In 1871, Lord Rayleigh derived the relationship between the percentage of light scattered, its wavelength and the saize of the particle the light dumps into.  He observed when light strikes small partials,  the percentage of scattering is inversely proportional to the 4th power of its wavelength.  This means shorter 400 nm  blue light is 10 times more likely to 'scatter' then longer 700 nm red light.

The color of the daylight sky is a result of incoming sunlight bouncing off Oxygen and Nitrogen molecules many times before it reaches our eyes.  Resulting in our azure sky.

So what happens at sunset?  White light containing all colors leaves the sun and goes through the earths atmosphere, the shorter blue wave lengths are scattered allowing mostly the longer red wave lengths to reach our retinas.  This in conjunction with larger dust particles creates the beautiful colors of the sunset.

Now, you can create this similar effect by shinning light through a glass of diluted milk!  Diluted white milk particles will give off blueish reflected light, but when same light is projected through the diluted milk, it will result in red color.  Not a brilliant sunset, but still an amazing thing: white light going into translucent white milk and producing color...