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Mk
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What are some reasons that the sky is blue?
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Why is the Sky Blue? Reasons Explained
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In summary: Water absorbs radiant energy ("light"). Water will more quickly absorb light with longer wavelengths. Water absorbs microwave and infra red wavelengths almost immediately, and visible red relatively quickly. If the red part of the spectrum is absorbed, then the gree/blue colors remain. This is why divers need flashlights that use the whole spectrum. Otherwise they would misidentify objects.The sky is blue due to scattering entirely. The blue light from the sun hits air molecules and is absorbed mometarily, then re-emitted in a random direction. REd light does not get so easily absorbed/re-emitted and thus maintains more of a straight line path, hence orange-red sun
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Cosmo16
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It is the way the light bends as it passes through the atomosphere. (Or somthinkg like that)
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stalefish
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http://en.wikipedia.org/wiki/Rayleigh_scattering
The amount of scattering depends on the frequency of the light. Blue light, having a higher frequency, scatters more than lower frequencies (Which pretty much pass straight through the atmosphere). This scattering of blue light more than the other visible frequencies results in us seeing the sky as blue.
The amount of scattering depends on the frequency of the light. Blue light, having a higher frequency, scatters more than lower frequencies (Which pretty much pass straight through the atmosphere). This scattering of blue light more than the other visible frequencies results in us seeing the sky as blue.
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Mk
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So is air blue? Water is generally blue, the greater the quantity the bluer it seems to get, is air the same way?
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stalefish
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Water itself isn't blue, really. Hey, it's the liquid we drink all the time!
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The_Thinker
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The reason water is blue, is because of the reflection of the blue sky on the water... that's all... water isn't blue...
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FredGarvin
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Why is the sky blue? If it were green we wouldn't know where to stop mowing.
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Conehead
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Answer
This peeling off of the lower frequencies in the spectrum (blues) is called Rayleigh scattering.
stalefish said:
This peeling off of the lower frequencies in the spectrum (blues) is called Rayleigh scattering.
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Conehead
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The_Thinker said:
No, actually Rayleigh scattering is at least partially responsible for water being blue too. The deeper you go in water the more of the spectrum is bounced out. At 33 feet you've lost the color red. At 66 feet you've lost orange.
This is the reason divers need flashlights that use the whole spectrum. Otherwise they would misidentify objects.
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Chi Meson
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Water absorbs radiant energy ("light"). Water will more quickly absorb light with longer wavelengths. Water absorbs microwave and infra red wavelengths almost immediately, and visible red relatively quickly. If the red part of the spectrum is absorbed, then the gree/blue colors remain.
gree-to-blue light is going to be scattered in the upper layers of water, so when viewed from above, water appers to be green-blue.
The sky is blue due to scattering entirely. The blue light from the sun hits air molecules and is absorbed mometarily, then re-emitted in a random direction. REd light does not get so easily absorbed/re-emitted and thus maintains more of a straight line path, hence orange-red sunsets.
The notion of water reflecting the sky is an oft-quoted misconception that is unfortunately still taught in grade-school "science" textbooks.
gree-to-blue light is going to be scattered in the upper layers of water, so when viewed from above, water appers to be green-blue.
The sky is blue due to scattering entirely. The blue light from the sun hits air molecules and is absorbed mometarily, then re-emitted in a random direction. REd light does not get so easily absorbed/re-emitted and thus maintains more of a straight line path, hence orange-red sunsets.
The notion of water reflecting the sky is an oft-quoted misconception that is unfortunately still taught in grade-school "science" textbooks.
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Mk
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So is water blue because water is blue? Or is it scattering? Or something else?
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Tide
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An important factor in the sky being blue is the presence of fluctuations in density and temperature (i.e. nonuniformity). Without such fluctuations the the Rayleigh fields will be canceled at every point.
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GENIERE
FredGarvin said:
You made me spill my coffee.
- #14
Mk
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Did it scatter? Or was it something else?GENIERE said:
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The best explanation (also with numerical values to get an idea) one can find in any of the 3 editions of J.D.Jackson's text on CED.
Daniel.
Daniel.
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Chi Meson
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Things are the color that they are due to teh frequencies of light that emerge from them. Ignoring whatever might be in the water (algae, mud, red tide etc) oceans are gree-blue because that is the light that scatters back out of the oceans.Mk said:
1. Why is the sky blue?
The sky appears blue because of the way sunlight interacts with Earth's atmosphere. When sunlight enters the atmosphere, it is scattered by the air molecules. The blue light has a shorter wavelength and is scattered more easily, making it more visible to our eyes.
2. Does the color of the sky change throughout the day?
Yes, the color of the sky can change throughout the day depending on the angle of the sun and the amount of particles in the air. During sunrise and sunset, the light travels through more of the atmosphere, causing longer wavelengths of light to be scattered and giving the sky a range of colors from red to orange.
3. Is the sky always blue on other planets?
No, the color of the sky on other planets depends on the composition of their atmospheres. For example, on Mars, the sky appears reddish due to the presence of iron oxide in the atmosphere. On Saturn's moon, Titan, the sky appears orange due to the presence of hydrocarbons.
4. Why is the sky sometimes a different shade of blue?
The color of the sky can vary based on the amount of moisture and particles in the air, as well as the time of day. The more water vapor and particles in the air, the more the blue light is scattered and the paler the sky appears. Additionally, during sunrise and sunset, the light must travel through more of the atmosphere, resulting in a deeper blue color.
5. Does the color of the sky have any impact on weather?
The color of the sky does not directly impact weather, but it can provide clues about the weather conditions. A bright blue sky can indicate clear and sunny weather, while a darker blue or gray sky can indicate the presence of clouds and possible rain or storms. However, it is important to note that the color of the sky is not always a reliable predictor of weather.
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