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2006-07-16 10:13:02 · 9 answers · asked by Lady Kagome 1 in Science & Mathematics Earth Sciences & Geology

9 answers

The atmosphere is the mixture of gas molecules and other materials surrounding the earth. It is made mostly of the gases nitrogen (78%), and oxygen (21%). Argon gas and water (in the form of vapor, droplets and ice crystals) are the next most common things. There are also small amounts of other gases, plus many small solid particles, like dust, soot and ashes, pollen, and salt from the oceans.

The composition of the atmosphere varies, depending on your location, the weather, and many other things. There may be more water in the air after a rainstorm, or near the ocean. Volcanoes can put large amounts of dust particles high into the atmosphere. Pollution can add different gases or dust and soot.

The atmosphere is densest (thickest) at the bottom, near the Earth. It gradually thins out as you go higher and higher up. There is no sharp break between the atmosphere and space.

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.

However, 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.







As 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.

2006-07-16 18:39:09 · answer #1 · answered by fzaa3's lover 4 · 0 0

Go here for the details
http://www.sciencemadesimple.com/sky_blue.html

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.

However, 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.

2006-07-16 17:18:16 · answer #2 · answered by Anonymous · 0 0

Diffuse sky radiation is solar radiation reaching the earth's surface after having been scattered from the direct solar beam by molecules or suspensoids in the atmosphere. Also called skylight, diffuse skylight, or sky radiation. Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25 percent of the incident radiation), about two-thirds ultimately reaches the earth as diffuse sky radiation.

Scattering is the process by which small particles suspended in a medium of a different index of refraction diffuse a portion of the incident radiation in all directions. In (elastic) scattering, no energy transformation results, only a change in the spatial distribution of the radiation. The science of optics usually uses the term to refer to the deflection of photons that occurs when they are absorbed and re-emitted by atoms or molecules.

The sky is blue partly because air scatters short-wavelength light in preference to longer wavelengths. Where the sunlight is nearly tangent to the Earth's surface, the light's path through the atmosphere is so long that much of the blue and even yellow light is scattered out, leaving the sun rays and the clouds it illuminates red, at sunrise and sunset.

Scattering and absorption are major causes of the attenuation of radiation by the atmosphere. Scattering varies as a function of the ratio of the particle diameter to the wavelength of the radiation. When this ratio is less than about one-tenth, Rayleigh scattering occurs in which the scattering coefficient varies inversely as the fourth power of the wavelength. At larger values of the ratio of particle diameter to wavelength, the scattering varies in a complex fashion described, for spherical particles, by the Mie theory; at a ratio of the order of 10, the laws of geometric optics begin to apply.

Individual gas molecules are too small to scatter light effectively. However, in a gas, the molecules move more or less independently of each-other, unlike in liquids and solids where the density is determined the molecule's sizes. So the densities of gases, such as pure air, are subject to statistical fluctuations. Significant fluctuations are much more common on a small scale. It is mainly these density fluctuations on a small (tens of nanometers) scale that cause the sky to be blue.

2006-07-16 17:23:05 · answer #3 · answered by duh 2 · 0 0

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.
The white light from the sun is a mixture of all colours of the rainbow. This was demonstrated by Isaac Newton, who used a prism to separate the different colours and so form a spectrum. The colours of light are distinguished by their different wavelengths. The visible part of the spectrum ranges from red light with a wavelength of about 720 nm, to violet with a wavelength of about 380 nm, with orange, yellow, green, blue and indigo between. The three different types of colour receptors in the retina of the human eye respond most strongly to red, green and blue wavelengths, giving us our colour vision

2006-07-16 17:18:24 · answer #4 · answered by Caidy 3 · 0 0

This question has been asked before, as I hope you saw in the "ask" page showing you what has been asked before. It has to do with the atmosphere scattering blue light more than red, so the blue light appears to come from all directions while the red is restricted to appearing to come from the sun. That is, except for sunsets when the red has to travel through more air to get to you.

2006-07-16 17:17:37 · answer #5 · answered by DakkonA 3 · 0 0

Because of oxygen and nitrogen around the earth, and since blue has the shortist wavelength, its diffused up to up to 10 times more than any other color.

2006-07-16 17:16:01 · answer #6 · answered by DT89ACE 6 · 0 0

So that people would ask the same question every two days.

2006-07-16 17:16:06 · answer #7 · answered by Anonymous · 0 0

the reflection of the ocean...

2006-07-17 06:32:20 · answer #8 · answered by Anonymous · 0 0

let me ask to my grandmom coz she is very close to sky...............

2006-07-16 17:20:03 · answer #9 · answered by gemglaze 2 · 0 0

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