Why is the sky and deep clean water blue ?

Answer 1

As for the sky (according to Wikipedia):
"During daylight the sky has the appearance of an opaque blue surface, but this is the result of the air scattering sunlight. [1]There is no "blue object" above the earth in any normal sense, so it is hard to say what object the sky is. The sky is thus sometimes defined as the denser gaseous zone of a planet's atmosphere. At night the sky has the appearance of a black surface or region scattered with stars. But if we then say that the sky is the entire visible universe, it would not be the same thing we see during the day. The color of the sky is a result of diffuse sky radiation. On a sunny day the Earth sky usually looks as a blue gradient — dark in the zenith, light near the horizon (due to Rayleigh scattering). It turns orange and red during sunrise and sunset, and becomes black at night."

As for water, it reflects the light from the sky. For a more technical answer, according to Wikipedia again, "Because water absorbs strongly in the infrared portion of the light spectrum, a small amount of visible red light is absorbed as well, resulting in water's slightly blue color when seen in mass quantities such as a lake or ocean." The water absorbs the red light and leaving bluish light to be reflected to our eyes.

Answer 2

Light from the sun is composed of waves of different lengths. These lengths are rendered by the human eye as different colours. Some of these wavelengths are scattered more as light passes through the atmosphere. Blue light is scattered more than the other colours so more light from that end of the spectrum reaches the surface and causes the sky to appear blue. The sea appears blue for a similar reason, blue light is refracted more readily from the surface than other colours. The reflection of the sky in the water is an additional factor.

Answer 3

calxaed and campbelp2002 are the most accurate. Wikipedia's article on Rayleigh scattering does a pretty good job of explaining it. http://en.wikipedia.org/wiki/Rayleigh_scattering

Deep water is blue for the same reason the sky is blue: Rayleigh scattering. it's not becasue the water is reflecting the color of the sky, this should be obvious since deep water is still blue on a cloudy day.

a related question is: why is snow white if it's made of water? or Why are clouds white?

the answers to those questions are something called Mie scattering http://en.wikipedia.org/wiki/Mie_scattering In the case of mie scattering, the particles which scatter the light are larger than the wavelength of light.

Answer 4

It has to do with the way the light is refracted. White light is a combination of the rainbow colours (red, orange, yellow, green, blue, indigo, violet). When the light hits gas molecules in the atmosphere, the light refracts into the separate colours like when you shine a light through a prism. The longer wavelengths can pass through easier (red, orange) whereas the smaller wavelengths (blue, violet) bounce off the gas molecules a lot. Because of this, it's more visible and the sky appears to be blue.

The water appears blue because it's reflecting the blue of the sky.

Answer 5

Small particles in the sky cause the light to scatter. The actually wavelength of the scattered light is closer to violet than it is to blue, but because of the human eye's sensativity to the blue wavelength and the fading of the color by water vapor, it appears sky blue. Water appears blue because it simply reflects the sky, hence why water looks dark gray when it is cloudy and such.

Answer 6

i'm not sure what you're asking. Why the sea is blue? That because of the incontrovertible fact that the water has a tendency to soak up the purple gentle, and mirror greater blue gentle. something of the colour variations are by way of algae, and sediments interior the water. additionally shallow water will mirror greater gentle reckoning on what shade the sea floor is.

Answer 7

the sky-i think is has to do with the molecules
the deep clean water-i think its a reflection of the color of the sky and since its so clean and so deep, it makes it seem darker than the sky and you can see the color to the bottom

Answer 8

It is due to Rayleigh scattering (named after Lord Rayleigh), which is the scattering of light, or other electromagnetic radiation, by particles much smaller than the wavelength of the light. It occurs when light travels in transparent solids and liquids, but is most prominently seen in gases. Rayleigh scattering of sunlight by the atmosphere is the main reason light from the sky is blue.

Answer 9

It is the reflection of sky on water, that looks blue.

Answer 10

It really isn't. It's just an optical illusion brought on by the vastness of what you're looking at/through. Is the sky/air right around you blue? Uh, no, it has no color...same thing.