why is the sky blue?

Question

is it really blue or does light from the ocean ,sky , sun etc make it that way? how long is the sky or sky line is long or a circle

Answer 1

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.

Answer 2

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 largger 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.

Answer 3

I think that anything that is blue, will be blue because it reflects blue light, but absorbs light of other colours. Since on a good day the sky is actually a light blue, this would mean that the light being reflected is actually both a mixture of blue and greens which produce a light blue colour. I guess it is the chemicals in our atmosphere that reflects mostly blue and green light, but it is a chemical that normally absorbs the red light. Different coloured objects reflects light from different parts of the spectrum (reflects light at different wavelengths).

Answer 4

why are plants green, whys is rust red, the same reason the sky id blue. the refraction of sunlight through oxygen/nitrogen. all the colors are filtered out but blue remains. the same reason plants are green all the colors are absorbed and the only on left is green

the sky at sunset/sunrise looks red beacuase of the angle of the sun through the atmosphere. at such a low angle red shows through, as its rises it turns more orange then all blue, but only the sky around the sun at set/rise looks red while the suns light excites the air and blue is fromed

water is mostly clear, the oceans look blue beacuase they reflect the sky blue

Answer 5

This is info i copied and pasted from a web site.
"http://mb-soft.com/public/bluesky.html
The Earth's atmosphere is primarily made of Oxygen and Nitrogen. It happens that both these are made up of atoms of about the same size. It also turns out to be true that EVERYTHING has lots of empty space between and around the atoms that it is made of.

Our Sun produces light which is actually a mixture of light of a lot of colors (another subject). You can prove this with a prism, which separates the colors. These various colors are actually just different sizes (frequencies) of waves of radiation (light). Our eyes only recognize the total of all this light, and so it appears to be a bright yellow, almost white color.

It turns out that RED light in the sunlight is the lowest frequency and therefore is the biggest wave (yet another subject!). These big waves happen to be bigger than the size of the oxygen and nitrogen atoms mentioned above. When these BIG waves pass through the earth's atmosphere they are not affected much by the relatively SMALL atoms of Oxygen and Nitrogen; so most RED light continues straight on through. (They are able to go around the atoms more than bumping into them.)

The BLUE light in the sunlight is the highest frequency (of what we can see) and therefore has the littlest waves. These smaller waves happen to be a little smaller than the size of the oxygen and nitrogen atoms. When these SMALL waves of blue light pass through the earth's atmosphere, many of them eventually "crash into" the relatively LARGE atoms of Oxygen and Nitrogen. They tend to "bounce off" (are reflected and refracted) and then they go all directions including sideways and down toward us.

A more scientific way of saying this is to say that the Oxygen and Nitrogen atoms are of a size that has a "natural vibration rate" that is similar to the rates of vibration of BLUE light. So the blue light can cause those atoms to start vibrating. The vibrating atoms then give off blue light when they stop vibrating, and that new blue light can go in any direction. (It's a little more complicated than that, but the general idea is correct.)

As sunlight is passing through the atmosphere horizontally above you, the RED light tends to go straight through, while the BLUE light tends to get bounced around (what is called "scattered") as described above. When you look up at open sky, you see this scattered light which is mostly BLUE.

Please notice that I keep saying things like "usually", "mostly", "tends",and not "always". Remember that there is a LOT of empty space between the atoms in the air. Some blue light CAN make it through a good distance of air. But, the farther that the light has to pass through air keeps making it more and more likely that the blue light will be scattered while a good amount of the red light will continue on through."



The second part of your question is a bit more complicated.

You need to learn about horizon. this should be helpful.
http://en.wikipedia.org/wiki/Horizon

Answer 6

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.

Why is the sky blue instead of violet?
Because of the strong wavelength dependence (inverse fourth power) of light scattering according to Raleigh's Law, one would expect that the sky would appear more violet than blue, the former having a shorter wavelength than the latter. There is a simple physiological explanation for this apparent conundrum. Simply put, the human eye cannot detect violet light in presence of light with longer wavelengths. There is a reason for this. It turns out that the human eye's high resolution color-detection system is made of proteins and chromophores (which together make up photoreceptor cells or "Cone" structures in the eye's fovea) that are sensitive to different wavelengths in the visible spectrum (400 nm–700 nm). In fact, there are three major protein-chromophore sensors that have peak sensitivities to yellowish-green (564 nm), bluish-green (534 nm), and blue-violet (420 nm) light. The brain uses the different responses of these chromophores to interpret the spectrum of the light that reaches the retina.

When one experimentally plots the sensitivity curves for the three color sensors (identified here as long (L), middle (M), and short (S) wavelength), three roughly "bell-curve" distributions are seen to overlap one another and cover the visible spectrum. We depend on this overlap for color sensing to detect the entire spectrum of visible light. For example, monochromatic violet light at 400 nm mostly stimulates the S receptors, but also slightly stimulates the L and M receptors, with the L receptor having the stronger response. This combination of stimuli is interpreted by the brain as violet. Monochromatic blue light, on the other hand, stimulates the M receptor more than the L receptor. Skylight is not monochromatic; it contains a mixture of light covering much of the spectrum. The combination of strong violet light with weaker blue and even weaker green and yellow strongly stimulates the S receptor, and stimulates the M receptor more than the L receptor. As a result, this mixture of wavelengths is perceived by the brain as blue rather than violet.

You could get more information from the link below...

Answer 7

The sky is generally blue because the light that is diffused in the atmosphere absorbs other colors but refracts the blue element of the light.

So we see blue.

The 'sky' encompasses the entire globe (its really just part of the planet).

-dh

Answer 8

I believe that the ultraviolet-blue light waves travel faster than any other color and that is why the sky appears blue. I also have heard that the water on our planet plays a part.

Answer 9

The sky is in fact not blue the sun reflects off of our ozone and that is what gives it the blue apperance.

Answer 10

the sky is blue because light is compressed when it hits the atmosphere, the ocean is blue because it reflects the sky not the other way around.