Why is the......?

Question

the sky blue? Now wait a minuite this is not just one of those dumb questions to get points. So please NO STUPID ANSWERS PLEASE!!!! I have heard from one source that it is becuse of the oxygen in the air but others say its blue from some form of reflection. I would really like to know.

Answer 1

Molecules of nitrogen and oxygen, which account for more than 98 percent of the gases that make up air, are just the right size to scatter blue light. The light from the sun is “white;” that is, it has all of the colors. But the blue colors “bounce” off of molecules of air, going in all directions. No matter what direction you look in during the day, blue light is coming toward you from the sky, unless clouds hide the sky.

Answer 2

I'm sure this question has been asked lots. The previous answers are completely right and this is just an addition to answer a specific point. The gases in the upper atmosphere scatter or, another word would be, reflects blue light. Other colours of light are not reflected, so we see a blue colour sky.

Answer 3

One of the most commom questions.
Here is my explanation, with limited physics:

The correct answer is that the molecules in the air scatter the blue wavelength of the spectrum (known as the Tyndall effect, or Rayleigh scattering), allowing the other wavelengths to pass through.That is fine, but I know science graduates who still don't understand this explanation.
Here is my explanation, with a limited amount of physics involved:

I think most people know that white light is made up of a spectrum of different colours, which can be broken down with a prism (or in a rainbow), showing a range of different colours, from red to blue. Technically, the red light has the longer wavelength, and the blue the shorter wavelegth (there are other wavelengths such as infrared and ultraviolet that our eyes cannot see).

When the light passes through the atmosphere, the red and yellow wavelengths pass right through, because their wavelength is larger than the size of the air molecules, and they don't interact. However, the blue wavelength is just the right size to hit the air molecules, and they bounce off in all directions (ie, they are scattered). (To understand this, imagine you are walking through a cloud of fine mist. It might be a bit unpleasant, but the tiny mist droplets are too small to cause you to slow down, and you can pass straight through. However, if you were walking through a packed crowd of people the same size as you, you couldn't pass through without colliding with and bouncing off some of the people. An elephant however, would have no trouble passing through).

That is why, when we look up at the sky, the sky seems blue, and the blue colour seems to be coming from all directions. We are seeing that scattered blue light (closer to the sun, the blue colour is not as strong. because of the red and yellow light passing straight through). When the light reaches us on the ground, we see the combined effect of the red and yellow wavelength light passing straight though, mixed with the blue light reaching us from the sky.

If you see a sun beam passing through a narrow space into a dark room (eg through a slit in a blind) it will look more yellow, because it lacks the scattered blue part of the spectrum.

That is a simplified answer, and not scientifically accurate, but is the best explanation I can think of, without using physics.

Answer 4

Because the sun emits white light, which contains all of the colors. The composition of our atmosphere scaters more of the blue than the others, thereby making the sky look blue.

Answer 5

due to atmospheric reflection blue life is reflected more than other colours so it looks blue