what makes the sky appear blue?
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The sun's rays hit the Earth's atmosphere, where the light is scattered by nitrogen and oxygen molecules in the air. The blue wavelength of this light is affected more than the red and green wavelengths, causing the surrounding air to appear blue. At sunset, the sun's light passes farther through the atmosphere, deflecting and decreasing the blue in the air. Scattering by dust particles and pollution in the air causes the sunset to appear red.
505255
The sky is air.  Air is transparent, mostly.  However, air does slightly bend very high frequencies of visible light.  These frequencies include purple and blue.  This makes the sky appear blue.\n\nWhen the Sun is near the horizon at sunrise and sunset, its light is passing through much more air (about 4000 miles' worth, instead of the overhead air that is about 50 miles thick), and much more light is bent out.  This is why the sky turns red.
476620
The sky is blue because it would be ugly red....JK. The sky is blue because of all the mixes of gases in the atmosphere.  ;)
1015359
using simple physics\n\nThe blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air.\n\nthe grass is green because the other colors are absorbed and only green is reflected. Grass and most other plants are green because they contain a pigment known as chlorophyll.\n\nSun isn't really yellow. The color yellow is a purely human interpretation of a collection of radiation that hits the retinae of our eyes and gets processed by our visual cortex.
278514
The sky is colourless. It is black. Scientifically at least.\n\nThe sun's rays of light reflect off water and those coloured rays are reflected onto the sky. That is why the sky looks blue. \n\nWhen it changes to other colours it depends on how much light the sun gives off and what colour that makes the surface of the water. That is also why, at night, when the sun is gone, the sky is black.
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1. Why the sky is blue.\nWhen light passes through a medium with molecules much smaller than the wavelength, it is scattered. You can understand it so: the light begins by going as a beam "forward". It gets absorbed for a moment by a molecule and then emitted again in whatever direction. This effect is more effective when the wavelength is shorter. Blue light has a wavelength ~2 times shorter than red light and gets scattered 16 times as effectively. So the beam coming directly from the sun is deprived of blue =>thus it is yellow (or red if it is sunset and it has passed a thick layer of atmosphere (geometry)). From all other directions we see the light that was going towards other points on the Earth. The yellows and reds went on and the blue was sent in other directions, including towards us.\n\n2. Why the grass is green.\nGreen plants use light to make food. The light is absorbed by chlorophyll (two types of it, too and a bit different, but no matter). Chlorophyll absorbs violet, blue, orange and red light. What we see is what was not absorbed, but reflected. If you take the aforementioned colours out of the white light spectrum, you get a mixtureof green and yellow. And green is the colour our eyes see best. Thus - green grass.\n\nI hope I've been clear
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Blue is the color that is reflected from the atmosphere--alll over colors are absorbed...Light is divided into the colors of the spectrum and each color has it's own specific wavelength.....so the wavelength for "blue light" is reflected and not absorbed and that is why you see a blue sky.
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They know the sky is blue because the verrrrrry small particles up there refract blue light from the sun the best, and thus the overall color of the sky is blue.
124021
A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light.  When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.
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reflection of light\n\nDuring daylight the sky has the appearance of a deep 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.
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Why is the sky blue: Discussion \nTransmitted light (from the sun, light bulbs, fire, etc) is made up of a spectrum of colors. The longest wavelengths of light are on the red end of the spectrum and the shortest wavelengths are on the blue/violet end of the spectrum.\nWhen transmitted light such as sunlight enters our atmosphere it collides with the oxygen and nitrogen atoms. The color with the shorter wavelength is scattered more by this collision. Because violet and blue are the shortest wavelengths the sky appears to be violet / blue. But because our eyes are more sensitive to blue light than they are violet light, we perceive the sky as blue.\nOur eyes contain thousand of rods and cones, which are the receptors for light. Whenever one of the 3 Stooges pokes you in the eye you see a giant blue spot. This is because the blue receptors have been activated. Blue is one of the primary colors and thus more easily activated and seen by our eyes.
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When the light from the sun hits the earth some of the light (The higher frequency or blue light) gets trapped or rather scattered by the smaller molecules in the atmosphere.  This scattering makes the sky blue because these particles reflect this blue light.\nAt night the light we are seeing is  the light of  the sun reflected off of the moon and it is much less intense.
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there are defferent sphares of light.   White light comes from the sun and when it hits the atmospher it splits into different colors of the rainbow.  Blue being the fastest light is the only light that escapes the atmospher and that is what makes a blue sky.  Blue skies also mean clear skies.  now a red sky means lots of deferent types of air in the sky.  in the morning the sun is just starting to warm up the atmospher.  so you have a lot of defferent types of air going to get charged up.   Think of it like starting all the appliences  in your kitchen starting up but you don't know what they are gonna do.  basically you get speratic weather.  As apposed to a blue sky getting warmed up.  All it does is warm up the air.    \n \nhope this helps\n-David-
28059
because it reflect the color of the sky? what happens to a blue ocean wehn the sky turns dark. The ocean turns dark. Simple
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it's all about water\nwater in the atmosphere is like a beam splitter to the light, and at the angle we're at to the beams of light, the sky looks blue
672709
To answer this question, you should know that the white light is made up of seven different colors (violet, indigo, blue, green, yellow, orange and red). When sunlight (which is white colored) hits the Earth's atmosphere the blue components of the white light bend so much that it seems like they surround the Earth causing the sky to look blue. \nThe seas llok blue because they act like a mirror and they reflect the sky. The sea color is darker than the sky because of the depth of the seas (Beer-Lambert's Law). The rivers are not suppose to be deep and that's why they don't appear blue. If human eyes were really strong then we could have seen that the rivers are slightly blue.
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The sky appears blue due to the scattering of sunlight by dust particles in the air.\n\nSunlight is comprised of light in different wavelengths and can easily be split with a prism.  The dust particles in the air are of the right size that they scatter blue light preferentially.  As a result, we see the sky blue.\n\nThe sky is black at night simply because there isn't any blue light to be scattered.\n\nIncidentally, moonlight is yellow because that is the generally reflected colour off the moon's surface.  It is reflected light strongly in the yellow waveband. The yellow light is not affected by atmospheric scattering.