why is the sky blue?

Answer 1

Because God wanted to use his most beautiful shade of blue, and the sky was next on his list to be painted.

Answer 2

This question has been asked over 4000 times, and I've prepared a simple answer, without too much science:

The correct answer is that the blue light is scattered by the air molecules in the atmosphere (referred to as Rayleigh scattering). The blue wavelength is scattered more, because the scatteing effect increases with the inverse of the fourth power of the incident wavelength.

OK, but I've known science graduates who don't understand what this means.
Here's my attempt at an answer without too much physics:

I think most people know that sunlight is made up of light of several different wavelengths, and can be split up into the colours of the rainbow. Blue light has the shorter wavelength, and red the longest wavelength.

When sunlight hits the molecules in the atmosphere, the light strikes the molecules and is absorbed, causing the molecules to vibrate and give off, or 're-emit' the lightt.

Because the blue wavelength is shorter and more energetic, it reacts much more with the air molecules than the red and yellow wavelengths; which tend to pass straight through.

Because the blue radiation is re-emitted from the air molecules in all directions ('scattered'), it seems to us looking from the ground that the blue light is coming from everywhere; hence the sky seems blue.

Near sunset, because of the low angle of the sunlight, we see more of the red and yellow wavelendth passing straight through, hence the colours of the setting sun.

BTW: The sky isn't blue because of a reflection of the sea; its the other way round, although the blue colour of the sea is mostly caused by the water molecules scattering the blue light, in a similar way. This effect is even stronger with ice; which results in the intense blue colour we see if we look down a crevasse in a glacier, or down a hole in the snow made by a ski stock..

For a complete, scientific explqanation, look up 'blue sky' in Wikipedia.

Answer 3

The molecules in earth's atmosphere scatter blue light more than the other colors. While most light passes in a more or less straight line from the sun to your eye, the blue light is scattered and comes from all directions to your eye rather than just from the sun. Thus the sun is yellow-orangish and the sky is blue even though the sun in space appears white.

The fact that clean water is blue is the exact same effect. Also, the sky being blue has absolutely nothing to do with reflection off water. If that were true, then it should be green if you live deep inside a forrest or a grassy plain.

Answer 4

There is a physical phenomenon called Rayleigh scattering that causes light to scatter when it passes through particles that have a diameter one-tenth that of the wavelength (color) of the light. Sunlight is made up of all different colors of light, but because of the elements in the atmosphere the color blue is scattered much more efficiently than the other colors.

So when you look at the sky on a clear day, you can see the sun as a bright disk. The blueness you see everywhere else is all of the atoms in the atmosphere scattering blue light toward you. (Because red light, yellow light, green light and the other colors aren't scattered nearly as well, you see the sky as blue.)

Answer 5

The molecules in the atmosphere bounce off of the sun's rays which in turn reflect from the ocean. Since the world is made up mostly of water, the tinted hugh of the sky reflects the water and makes an illusion of a Blue sky.

Answer 6

according to what i have read, the light that comes from the sun is composed of the red, orange, yellow, green ,blue , indigo, and violet lights, when the light from the sun (white light) radiates, the first light which strikes the atmosphere is th blue light thats why the sky is blue

Answer 7

Agree with 1st answer - this planet is blue (mostly) so the light reflected back into space is blue from the spectrum of colours provided to us by the sun

http://www.sciencemadesimple.com/sky_blue.html <<< will help you understand better & there is pictures - WoW!

Answer 8

it;s because of the scattering of the light. light has colors ROYGBIV. viloet is teh most scattered and next is blue but our eyes are not sensitive to color violet, it is the blue that our eyes are sensitive that's why we see the sky as blue.

Answer 9

The water in the sea or ocean water extends to wherever you can see up there

Answer 10

ive been answering this for a million times..
just joking.. people always ask this question..

ok.. here's your answer
go to http://www.math.ucr.edu/home/baez/physics/General/BlueSky/blue_sky.html