why is the sky blue?

Answer 1

Its due to the gases in the atmosphere absorbing wavelengths of light. and blue is absorbed the least so it shows up blue.

Answer 2

To start of with we must understand what light is.

Light isnt just made up of 1 colour, it contains a number of different colours each of which has a different wavelength. Light is split up into the following colours with the first having the longest wavelenght and the last having the shortest.

Red
Orange
Yellow
Green
Blue
Indico
Violet

An easy way to rememeber this is ROY G BIV (my year 12 geology teacher taught me that about 8 years ago)

As light moves through the atmosphere, most of the longer wavelengths are able to pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules in the atmosphere which is mainly nitrogen (78%) and oxygen (21%). The absorbed blue light is then scattered in all different directions. Since you see the blue light from everywhere overhead, the sky looks blue.

On Earth, the sun appears yellow. If you were out in space, or on the moon, the sun would look white. In space, there is no atmosphere to scatter the sun's light. On Earth, some of the shorter wavelength light (the blues and violets) are removed from the direct rays of the sun by scattering. The remaining colors together appear yellow.

You didnt ask about sunsets, but what the heck it may come in handy some day :)

What happens during sunsets is that as the sun begins to go down, the light must travel farther through the atmosphere before it gets to you. More of the light is reflected and scattered. As less light reaches you directly, the sun appears less bright. The color of the sun itself appears to change, first to orange and then to red. This is because even more of the short wavelength blues and greens are now scattered. Only the longer wavelengths are left in the direct beam that reaches your eyes.

Hope this helped you out a bit.

Answer 3

Here's why. Our sky is colored because our atmosphere makes blue light when sunlight passes through it. This phenomenon is called "scattering." It is similar to when sunbeams reveal themselves in the presence of dust, most spectacularly in cathedrals. The atmosphere causes the sky to be colored. If there were no atmosphere, the sky would appear black, like the lunar sky in Apollo pictures taken from the moon. But even a black sky has some lightness... Even at night, the sky always has a faint color, called "skyglow" by astronomers. Atmospheres also cause skyglow from faint airglow in the upper atmosphere (a permanent, low-grade aurora), and starlight scattered in the atmosphere. Even if there were no atmosphere, faint skyglow is caused by sunlight reflected off interplanetary dust (zodiacal light), and background light from faint, unresolved stars and nebulosity. Blue wavelengths are generally scattered down toward the earth. This makes the sky appear blue wherever it is daytime (and the sun is high in the sky).

Answer 4

I think you will find your answer here: http://www.why-is-the-sky-blue.tv/why-is-the-sky-blue.htm

My understanding is mainly because of the massive reflection of the sun off the blue the oceans creating a blue sky.

Answer 5

It is because of the refraction of light through the atmosphere and the wavelength caused by the thickness and purity of the atmosphere. Notice it is red in the evening when sunlight has to pass through a greater thickness due to the angle.

Pollution will alter the wavelength.

Answer 6

i'm not sure specifically why, but I think it's something to do with o-zone, I think it's a blue gas and the suns rays reflecting back off the earth make the colour more obvious. I think!

Answer 7

Rayleigh Scattering of photons is the cause for the sky being blue!

See - http://hyperphysics.phyastr.gsu.edu/hbase/atmos/blusky.html

Answer 8

It's not. its a optical illusion. And it looks a gloomy grey here with rain falling from it

Answer 9

Due to scattering of light.

Answer 10

It lost its job, its wife is leaving, and its dog bit it.