English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

I have always wondered

2006-09-14 06:44:49 · 27 answers · asked by AlOnEiNtHeRaIn 3 in Environment

27 answers

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.
Blue light has has a shorter optical path length (around 49 km/30.6 miles) than red light (around 180 km/112.5 miles). Therefore, the diffusion process of blue light is more efficient. On the other hand, sunrise and sunset are red because light has to cover a longer distance through high-density areas within the atmosphere. Blue light is substantially diffused, so the sky turns red.

This question has been asked several times here in Y!Q&A.Check out this link to review different versions of the answers.:http://answers.yahoo.com/search/search_result;_ylt=AtIGB7daFjvICisAzCY2MywezKIX?p=Why+is+the+sky+blue

2006-09-14 06:54:46 · answer #1 · answered by ♥ lani s 7 · 0 0

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.

2006-09-14 13:47:27 · answer #2 · answered by CJM 3 · 0 0

The color of the sky is a result of diffuse sky radiation and the fact that air is actually a very transparent blue color. 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.

The sky is blue partly because air scatters short-wavelength light in preference to longer wavelengths. Combined, these effects scatter (bend away in all directions) some short, blue light waves while allowing almost all longer, red light waves to pass straight through. When we look toward a part of the sky not near the sun, the blue color we see is blue light waves scattered down toward us from the white sunlight passing through the air overhead. Near sunrise and sunset, most of the light we see comes in nearly tangent to the Earth's surface, so that 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.

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.

2006-09-14 13:48:57 · answer #3 · answered by GoodGuy 3 · 0 0

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.

2006-09-14 13:47:11 · answer #4 · answered by Bedroom Celebrity 3 · 0 0

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.

2006-09-14 13:46:34 · answer #5 · answered by Miss Mouse 6 · 1 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.

The color of the sky is a result of diffuse sky radiation and the fact that air is actually a very transparent blue color.

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.

2006-09-14 13:45:58 · answer #6 · answered by Anonymous · 0 0

Because of the way the sun reflects off the atmospheric particles flying around the sky.

Or something like that.

2006-09-14 13:46:07 · answer #7 · answered by Anonymous · 0 0

Rayleigh scattering (named after Lord Rayleigh) 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.

2006-09-14 20:01:12 · answer #8 · answered by Anonymous · 0 0

The wavelength of the sun hitting the atmosphere. look at sunset and you could give the same question and answer then too. Blue is shortest on the visible light scale; when the sun is overhead. and longest on the red end; evening the sun is more of an angle to above.

2006-09-14 13:47:58 · answer #9 · answered by SST 6 · 0 0

The sky is blue and the grass is green. God made it that way, I'm sure glad he didn't give us gloomy colors.

2006-09-14 13:47:41 · answer #10 · answered by Tyranus 3 · 0 0

fedest.com, questions and answers