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Why Does The Sky Look Blue?
When we look up into the sky during a clear day we see a sky that is blue. But why is it that the sky is Blue?
The light that lights up the sky comes from the Sun and the Suns light is actually made up of different colors that would under normal circumstances look white to us. However there are lots of different factors that cause the Suns light to turn the Sky Blue.
The only time you will see all the colors is when the light travels through raindrops and creates a rainbow.
Rainbows and light refraction
Rainbows are a great example of what happens on the light from the sun once it enters our atmosphere.
When the suns rays enter a rain drop they are bent downward slightly before being bounced off the back surface of it. It then gets bent upward slightly as it leaves the raindrop. This bending and bouncing of the light causes it to separate into its individual colors which causes the rainbow to form.
The reason the colors are always in the same order is to to with the wavelength of each color. Red had the longest wavelength and so is bent the leased and indigo has the shortest wavelength an so is bent the most.
Each color that we see is emitted from a different raindrop not the same one even thought each raindrop will emit all the colors. This is because only one color coming out of each raindrop is at the correct angle to hit you in the eye. This is also the reason we see an arc.
(See Image Above)
It is this refraction and reflection of light that tuns the Sky blue.
When the suns rays reach the earth they have to enter the atmosphere and travel through it. The Earths atmosphere is made up of lots of different gases and full of all sorts of different particles. As the light passes through the air the particles that it hits cause it to scatter.
Because blue light has a short wavelength it gets scattered more than the other colors. It is because of the way that the light is scattered that we see a blue sky.