why sky's blue?

Answer 1

The sky isn't blue, it is black. It only appears blue because of the way that the light filters through the atmosphere.

Answer 2

The sky is blue because the sun's rays reflect on the Earth and interferes with the planets rotation. Because the Earth is 90% percent water. The sky reflects is a cool blue. The moister is caught in the planets atmosphere which depending on the planets orbit around the sun. Reflect the season and temperature along with the Earth's 24 hour rotation which changes the planets temperature at a daily rate.

Answer 3

Dear Siva,

The thing is that sky is never blue or even it does not hold any color. Infact any light when emmitted after it gets reflected from some object or particle it then gives some color.

The color which appears is actually the color that is not absorbed by the particles / object and the same color the body or object appears.

About color of sky, during day time it would appear you blue but during night it appears black. The thing is that during day time the light emmitted by sun get reflected from the particles of ionosphere. And the particles does not absorb blue color hence they appear to be blue

Answer 4

The sun gives off lots of different colors of light. The wavelength of light determines what happens to it when it strikes our atmosphere. Blue light is scattered much more easily by atmospheric gasses than other colors of light (because of its wavelength).

The sun's light contains lots of different wavelengths of light which, when seen together, look yellow. That just happens to be how they look. That is also why the sun appears to be yellow when you look at it. When you see the sun in the sky, the light is, of course, not just hitting you, but is hitting your half of the earth's atmosphere. When it hits the atmosphere, blue light immediately begins to scatter, and some of it scatters towards you. That is why you see blue light everywhere in the sky on a sunny day.

Red light scatters too, but not nearly as much as blue light. So when the sun is setting, and light must travel through a lot more atmosphere to reach you than when the sun is in the middle of the sky, the blue light all scatters away before it reaches you. The red light does not scatter completely away, but spreads to create the beautiful red sunsets that we are used to seeing.

That is why the sky is blue and sunsets are red. It is not because of pollution. It is not a special property of nitrogen or of oxygen.

Answer 5

The sky is blue because all the colors of light that come from sun to the earth are absorbed by the earth and the only color reflected back is blue. So the sky appears blue.

Answer 6

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..

Answer 7

Wow. 10 answers and no one got it right.

Sunlight entering our atmosphere is scattered by the water in the atmosphere - Rayleigh scattering. Blue light, at shorter wavelengths, is scattered more than red light. The Sun emits almost as much blue light as red light, but the blue is scattered in all directions (to cover the sky and make it appear blue during the day) whereas most of the red/yellow makes it straight to your eyes.

This is also why the Sun appears red on the horizen - you're looking through more atmosphere on the horizen then you are overhead, and even the yellow light, with a shorter wavelength than red, is scattered, and the Sun appear red.

Answer 8

The sky is blue because the moister in the atmosphere acts like a filter for light and since water is blue it lets mostly blue through. It doesn't block all other colors it just lets blue through the best.

Answer 9

The main reason is that the sky is blue and not black is because of the ionosphere which reflects certain wavelenghts of light and absorbs others. Hence why the sky is blue.

Answer 10

The sky is blue bcoz of rayleigh's scattering effect