How come the sky is blue?
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If you want a very simple answer, here it is:\n\nThe white light from the sun is a mixture of all colours of the rainbow.\n\nA 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.
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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Neither is blue. \n\nThe SKY\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\nHowever, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. \n\nThe Sea.\nParticles and solutes can absorb light, as in tea or coffee. Green algae in rivers and streams often lend a blue-green color. The red sea has occasional blooms of red Trichodesmium erythraeum algae. \nParticles in water can scatter light. The Colorado river is often muddy red because of suspended reddish silt in the water. Some mountain lakes and streams with finely gound rock, such as glacial flour, are tourquise. Light scattering by suspended matter is required in order that the blue light produced by water's absorption can return to the surface and be observed. Such scattering can also shift the spectrum of the emerging photons toward the green, a color often seen when water laden with suspended particles is observed. \nThe surface of seas and lakes often reflect blue skylight, making them appear bluer. [[[ Montana reflection.]]] The relative contribution of reflected skylight and the light scattered back from the depths is strongly dependent on observation angle.
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When 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.\n\nIt is because blue light from the sun strikes the air molecules and scatters and our eyes perceive it as blue.\n\nBlue in sunlight collides with air molecules and our eyes see it as blue.
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I answer this question nearly every day.  *sigh*  :) :)\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\nHowever, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. \n\nAs you look closer to the horizon, the sky appears much paler in color. To reach you, the scattered blue light must pass through more air. Some of it gets scattered away again in other directions. Less blue light reaches your eyes. The color of the sky near the horizon appears paler or white.
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The light during the day comes from our star, the sun. The sunlight has to travel through air to get to us. The sunlight looks white, but it has many colors in it (for example, a prism or a rainbow breaks the sunlight into its colors so we can see them). \n\nSome of the blue part of the sunlight cannot go through the air without getting bounced around first by the air, and so it makes it look like the blue is coming from the air in the sky instead of the sun. That is why the sky looks blue.
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Possibly because you are colorblind and can not see the color blue.\n\nOr because you are blind and can not see.\n\nOr, how about because it is night time, and the increase of light from our sun isn't exciting particles of water to make the spectrum blue.  Instead, the absence of such light allows us to not see this type of distortion and see into space properly. \n\nOr, because the density of the clouds has reached a critical point and it is about to storm or rain.\n\nOr because you are weating sunglasses that distort your view.\n\nLOL this is a very subjective question witout the proper context.
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First off why is the sky any color at all and not black?\nThe answer -- the presence of the atmosphere -- oxygen molecules absorb energy and release at pretty much a random angle(Rayleigh scattering). So the light from the sun is "diffused" around the atmosphere and when it reaches our eyes it come in from all directions -- creating the colored sky effect.\n\nNow on to the 2nd question why is the sky specifically blue. Blue is high energy color(it is created by high frequency waves) so it does not spread as much as other colors. In fact the sky is not uniform blue -- Come out of your house on a clear sunny day and you will see that the sky is the bluest directly above your head but it gets more and more white as you look toward horizon. This means that blue light diffuses the least creating blue appearance around the sun -- but as you look further from the sun more colors are visible creating the white effect. \nThe Sky may also be seen in weird colors like red and orange when the sun is at the sharp angle with the atmosphere(dusk and dawn).
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Rayleight Scattering.\n\nThe blue color of the sky is caused by the scattering of sunlight off the molecules of the atmosphere. This scattering, called Rayleigh scattering, is more effective at short wavelengths (the blue end of the visible spectrum). Therefore the light scattered down to the earth at a large angle with respect to the direction of the sun's light is predominantly in the blue end of the spectrum.
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The sky is blue due to the way that light is bent, it's called Rayleigh Scattering.  Sunlight is white and white light consists of all colors but when it hits our atmosphere the light is broken up into it's component colors by the particles in the atmosphere.  The shortest wavelengths don't make it through the particles but the blue light does - hence the sky appears blue when in fact it has no color ro it (it is after all, nothing but air and water).\n\nAs others have said - grass is green because of chlorophyll - the chemical in all plants and it just happens to be green.
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The sky is blue to us beause of Rayleigh scattering.  From outer space, you don't have that atmosphere effect, so it's black.
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The water particles,mixed in the air ( sky ), are responsible for this.The sunlight is refracted by those water molecules and thus we see the colour of the sky as blue.As you may remember,in the rainbow colours,Blue comes just after Violet and Indigo which are not that prominent as Blue. \nThus we see the sky blue.
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because of water vapor (in the air...gives it a blueish hue.  not much to due with physics... maybe chemistry.
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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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because the atmosphere absorbs most of the other colors of the spectrum so all you see is mainly blue.
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Ocean's colour seems to be blue because it gets the sky's reflection over it.\nAnd the colour of the sky is blue bcuz of the various gases present in the atmosphere\nMainly nitogen and oxygen.
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The 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\nHowever, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. \nAs you look closer to the horizon, the sky appears much paler in color. To reach you, the scattered blue light must pass through more air. Some of it gets scattered away again in other directions. Less blue light reaches your eyes. The color of the sky near the horizon appears paler or white.