why is the sky blue?

Answer 1

THE ATMOSPHERE

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.


Light is a kind of energy that radiates, or travels, in waves. Many different kinds of energy travel in waves. For example, sound is a wave of vibrating air. Light is a wave of vibrating electric and magnetic fields. It is one small part of a larger range of vibrating electromagnetic fields. This range is called the electromagnetic spectrum.

Electromagnetic waves travel through space at 299,792 km/sec (186,282 miles/sec). This is called the speed of light.

Light waves

The energy of the radiation depends on its wavelength and frequency. Wavelength is the distance between the tops (crests) of the waves. Frequency is the number of waves that pass by each second. The longer the wavelength of the light, the lower the frequency, and the less energy it contains.

COLORS OF LIGHT

Visible light is the part of the electromagnetic spectrum that our eyes can see. Light from the sun or a light bulb may look white, but it is actually a combination of many colors. We can see the different colors of the spectrum by splitting the light with a prism. The spectrum is also visible when you see a rainbow in the sky.


The colors blend continuously into one another. At one end of the spectrum are the reds and oranges. These gradually shade into yellow, green, blue, indigo and violet. The colors have different wavelengths, frequencies, and energies. Violet has the shortest wavelength in the visible spectrum. That means it has the highest frequency and energy. Red has the longest wavelength, and lowest frequency and energy.


Light travels through space in a straight line as long as nothing disturbs it. As light moves through the atmosphere, it continues to go straight until it bumps into a bit of dust or a gas molecule. Then what happens to the light depends on its wave length and the size of the thing it hits.

Dust particles and water droplets are much larger than the wavelength of visible light. When light hits these large particles, it gets reflected, or bounced off, in different directions. The different colors of light are all reflected by the particle in the same way. The reflected light appears white because it still contains all of the same colors.

Gas molecules are smaller than the wavelength of visible light. If light bumps into them, it acts differently. When light hits a gas molecule, some of it may get absorbed. After awhile, the molecule radiates (releases, or gives off) the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the colors can be absorbed. But the higher frequencies (blues) are absorbed more often than the lower frequencies (reds). This process is called Rayleigh scattering. (It is named after Lord John Rayleigh, an English physicist, who first described it in the 1870's.)




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 sky from scattered light

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.

Sky paler at horizon

THE BLACK SKY AND WHITE SUN

On Earth, the sun appears yellow. If you were out in space, or on the moon, the sun would look white. In space, there is no atmosphere to scatter the sun's light. On Earth, some of the shorter wavelength light (the blues and violets) are removed from the direct rays of the sun by scattering. The remaining colors together appear yellow.

Also, out in space, the sky looks dark and black, instead of blue. This is because there is no atmosphere. There is no scattered light to reach your eyes.

Black sky in space



As the sun begins to set, the light must travel farther through the atmosphere before it gets to you. More of the light is reflected and scattered. As less reaches you directly, the sun appears less bright. The color of the sun itself appears to change, first to orange and then to red. This is because even more of the short wavelength blues and greens are now scattered. Only the longer wavelengths are left in the direct beam that reaches your eyes.

Sun red at sunset

The sky around the setting sun may take on many colors. The most spectacular shows occur when the air contains many small particles of dust or water. These particles reflect light in all directions. Then, as some of the light heads towards you, different amounts of the shorter wavelength colors are scattered out. You see the longer wavelengths, and the sky appears red, pink or orange.












The atmosphere is the mixture of gases and other materials that surround the Earth in a thin, mostly transparent shell. It is held in place by the Earth's gravity. The main components are nitrogen (78.09%), oxygen (20.95%), argon (0.93%), and carbon dioxide (0.03%). The atmosphere also contains small amounts, or traces, of water (in local concentrations ranging from 0% to 4%), solid particles, neon, helium, methane, krypton, hydrogen, xenon and ozone. The study of the atmosphere is called meteorology.

Life on Earth would not be possible without the atmosphere. Obviously, it provides the oxygen we need to breath. But it also serves other important functions. It moderates the planet's temperature, reducing the extremes that occur on airless worlds. For example, temperatures on the moon range from 120 °C (about 250 °F) in the day to -170 °C (about -275 °F) at night. The atmosphere also protects us by absorbing and scattering harmful radiation from the sun and space.

Of the total amount of the sun's energy that reaches the Earth, 30% is reflected back into space by clouds and the Earth's surface. The atmosphere absorbs 19%. Only 51% is absorbed by the Earth's surface.

We are not normally aware of it but air does have weight. The column of air above us exerts pressure on us. This pressure at sea level is defined as one atmosphere. Other equivalent measurements you may hear used are 1,013 millibars, 760 mm Hg (mercury), 29.92 inches of Hg, or 14.7 pounds/square inch (psi). Atmospheric pressure decreases rapidly with height. Pressure drops by a factor of 10 for every 16 km (10 miles) increase in altitude. This means that the pressure is 1 atmosphere at sea level, but 0.1 atmosphere at 16 km and only 0.01 atmosphere at 32 km.

The density of the lower atmosphere is about 1 kg/cubic meter (1 oz./cubic foot). There are approximately 300 billion billion (3 x 10**20, or a 3 followed by 20 zeros) molecules per cubic inch (16.4 cubic centimeters). At ground level, each molecule is moving at about 1600 km/hr (1000 miles/hr), and collides with other molecules 5 billion times per second.

The density of air also decreases rapidly with altitude. At 3 km (2 miles) air density has decreased by 30%. People who normally live closer to sea level experience temporary breathing difficulties when traveling to these altitudes. The highest permanent human settlements are at about 4 km (3 miles).



The atmosphere is divided into layers based on temperature, composition and electrical properties. These layers are approximate and the boundaries vary, depending on the seasons and latitude. (The boundaries also depend on which "authority" is defining them.)



Homosphere

· The lowest 100 km (60 miles), including the Troposphere, Stratosphere and Mesosphere.

· Contains 99% of the atmosphere's mass.

· Molecules do not stratify by molecular weight.

· Although small local variations exist, it has a relatively uniform composition, due to continuous mixing, turbulence and eddy diffusion.

· Water is one of two components that is not equally distributed. As water vapor rises, it cools and condenses, returning to earth as rain and snow. The Stratosphere is extremely dry.

· Ozone is another molecule not equally distributed. (Read about the ozone layer in the Stratosphere section below.)

Heterosphere

· Extends above homosphere, including the Thermosphere and Exosphere.

·Stratified (components are separated in layers) based on molecular weight. The heavier molecules, like nitrogen and oxygen, are concentrated in the lowest levels. The lighter ones, helium and hydrogen, predominate higher up.



Neutral atmosphere

· Below about 100 km (60 miles)

Ionosphere

· Above about 100 km

· Contains electrically charged particles or ions, created by the absorption of UV (ultraviolet) light.

· The degree of ionization varies with altitude.

· Different layers reflect long and short radio waves. This allows radio signals to be sent around the curved surface of the earth.

· The Aurora Borealis and Aurora Australis (the Northern and Southern Lights) occur in this layer.

· The Magnetosphere is the upper part of the ionosphere, extending out to 64,000 km (40,000 miles.) It protects us from the high energy, electrically charged particles of the solar wind, which are trapped by the Earth's magnetic field.



The atmosphere



Troposphere - Height depends on the seasons and latitude. It extends from ground level up to about 16 km (10 miles) at the equator, and to 9 km (5 miles) at the North and South Poles.

· The prefix "tropo" means change. Changing conditions in the Troposphere result in our weather.

· Temperature decreases with increasing altitude. Warm air rises, then cools and falls back to Earth. This process is called convection, and results in huge movements of air. Winds in this layer are mostly vertical.

· Contains more air molecules than all the other layers combined.

Stratosphere - Extends out to about 50 km (30 miles)

· The air is very thin.

· The prefix "strato" is related to layers, or stratification.

· The bottom of this layer is calm. Jet planes often fly in the lower Stratosphere to avoid bad weather in the Troposphere.

· The upper part of the Stratosphere holds the high winds known as the jet streams. These blow horizontally at speeds up to 480 km/hour (300 miles/hour)

· Contains the "ozone layer" located between 15 - 40 km ( 10 - 25 miles) above the surface. Although the concentration of ozone is at most 12 parts per million (ppm), it is very effective at absorbing the harmful ultraviolet (UV) rays of the sun and protecting life on Earth. Ozone is a molecule made of three oxygen atoms. The oxygen molecule we need to breathe contains two oxygen atoms.

· The temperature is cold, about -55 °C (-67 °F) in the lower part, and increases with increasing altitude. The increase is caused by the absorption of UV radiation by the oxygen and ozone.

· The temperature increase with altitude results in a layering effect. It creates a global "inversion layer", and reduces vertical convection.

Mesosphere - Extends out to about 100 km (65 miles)

· Temperature decreases rapidly with increasing altitude.

Thermosphere - Extends out to about 400 km ( 250 miles)

· Temperature increases rapidly with increasing altitude, due to absorption of extremely short wavelength UV radiation.

· Meteors, or "shooting stars," start to burn up around 110-130 km (70-80 miles) above the earth.

Exosphere -Extends beyond the Thermosphere hundreds of kilometers, gradually fading into interstellar space.

· Density of the air is so low that the normal concept of temperature loses its meaning.

· Molecules often escape into space after colliding with one another.





Light is a kind of energy that can travel through space. Light from the sun or a light bulb looks white, but it is really a mixture of many colors. The colors in white light are red, orange, yellow, green, blue and violet. You can see these colors when you look at a rainbow in the sky.

Rainbow Picture

The sky is filled with air. Air is a mixture of tiny gas molecules and small bits of solid stuff, like dust.

As sunlight goes through the air, it bumps into the molecules and dust. When light hits a gas molecule, it may bounce off in a different direction. Some colors of light, like red and orange, pass straight through the air. But most of the blue light bounces off in all directions. In this way, the blue light gets scattered all around the sky.

When you look up, some of this blue light reaches your eyes from all over the sky. Since you see blue light from everywhere overhead, the sky looks blue.

Sky blue from scattered light

In space, there is no air. Because there is nothing for the light to bounce off, it just goes straight. None of the light gets scattered, and the "sky" looks dark and black.



a small mirror, a piece of white paper or cardboard, water
a large shallow bowl, pan, or plastic shoebox
a window with direct sunlight coming in, or a sunny day outdoor

What to do:

1. Fill the bowl or pan about 2/3 full of water. Place it on a table or the floor, directly in the sunlight. (Note: the direct sunlight is important for this experiment to work right.)
2. Hold the mirror under water, facing towards the sun. Hold the paper above and in front of the mirror. Adjust the positions of the paper and mirror until the reflected light shines on the paper. Observe the colored spectrum.





The water and mirror acted like a prism, splitting the light into the colors of the spectrum. (When light passes from one medium to another, for example from air to water, its speed and direction change. [This is called refraction, and will be discussed in a future issue.] The different colors of light are affected differently. Violet light slows the most, and bends the most. Red light slows and bends the least. The different colors of light are spread out and separated, and we can see the spectrum.)




a clear, straight-sided drinking glass, or clear plastic or glass jar
water, milk, measuring spoons, flashlight
a darkened room

What to do:

1. Fill the glass or jar about 2/3 full of water (about 8 - 12 oz. or 250 - 400 ml)
2. Add 1/2 to 1 teaspoon (2 - 5 ml) milk and stir.
3. Take the glass and flashlight into a darkened room.
4. Hold the flashlight above the surface of the water and observe the water in the glass from the side. It should have a slight bluish tint. Now, hold the flashlight to the side of the glass and look through the water directly at the light. The water should have a slightly reddish tint. Put the flashlight under the glass and look down into the water from the top. It should have a deeper reddish tint.
The small particles of milk suspended in the water scattered the light from the flashlight, like the dust particles and molecules in the air scatter sunlight. When the light shines in the top of the glass, the water looks blue because you see blue light scattered to the side. When you look through the water directly at the light, it appears red because some of the blue was removed by scattering.



a pencil, scissors, white cardboard or heavy white paper
crayons or markers, a ruler
a small bowl or a large cup (3 - 4 inch, or 7 - 10 cm diameter rim)
a paper cup



1. Use the bowl to trace a circle onto a piece of white cardboard and cut it out. With the ruler, divide it into six approximately equal sections.
2. Color the six sections with the colors of the spectrum as shown. Try to color as smoothly and evenly as possible.
3. Poke a hole through the middle of the circle and push the pencil part of the way through.
4. Poke a hole in the bottom of the paper cup, a little bit larger than the diameter of the pencil. Turn the cup upside down on a piece of paper, and put the pencil through so the point rests on the paper on a table. Adjust the color wheel's position on the pencil so that it is about 1/2 inch (1 - 2 cm) above the cup.
5. Spin the pencil quickly and observe the color wheel. Adjust as necessary so that the pencil and wheel spin easily.





What happened: The colors on the wheel are the main colors in white light. When the wheel spins fast enough, the colors all appear to blend together, and the wheel looks white. Try experimenting with different color combinations.



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Realistic onboard fuel cell model car with power supply.

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Aren't you feeling taunted enough to click the link? Why is the sky blue? Because it is feeling sad that humans don't last forever. Because yellow is already taken by that nimrod, the sun. Because it never gets to play in any of the reindeer games. Not the answer you were looking for was it? Now click the link. Please ...

Mis-information is at the heart of all of scientific inquiry. Plausible and implausible explanations need to be ruled out in order to understand what is really going on. Double-blind studies and other methods are good techniques that rule out mis-information. Once an explanation is ruled out it becomes fair game and fodder for sites like this to propound this information as if it were scientific fact. This site makes no apologies for dissemination of bogus facts, half-truths, shaky hypotheses and downright malicious lies, innuendo, tomfoolery and even shenanigans.

Science is not an exact science, someone once said. Okay, it was me. I said it. Be that as it may, the inexactness of science is what this website finds entertaining. Science can be art, you know. This is an earthy earth science site that contains little or no factual content whatsoever. What is informative about this? Whatsoever is the value in this, you ask? What is noteworthy is that science and those who participate in scientific endeavors many times take themselves way too seriously. Under the Shenanigan Theory of Relativity, science itself cannot be analyzed and taken apart and put underneath a microscope. Smirks cannot be synthesized into something useful. When is the last time you took a bunch of scientific ribaldry and analyzed the similarities in their DNA markers? A tumor has no humor. But we do, so read on and take whatever we say with a grain of salt because by the time you're done we will taste as salty as the ocean is blue.


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Blue sky over blue lake.

It is easy to see that the sky is blue. Have you ever wondered why? A lot of other smart people have, too. And it took a long time to figure it out!

The light from the Sun looks white. But it is really made up of all the colors of the rainbow.

A prism separates white light into the colors of the rainbow.

A prism is a specially shaped crystal. When white light shines through a prism, the light is separated into all its colors.

If you visited The Land of the Magic Windows, you learned that the light you see is just one tiny bit of all the kinds of light energy beaming around the Universe--and around you!

Like energy passing through the ocean, light energy travels in waves, too. Some light travels in short, "choppy" waves. Other light travels in long, lazy waves. Blue light waves are shorter than red light waves.

Different colors of light have different wavelengths.

All light travels in a straight line unless something gets in the way to--

* reflect it (like a mirror)

* bend it (like a prism)

* or scatter it (like molecules of the gases in the atmosphere)

Sunlight reaches Earth's atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.

Atmosphere scatters blue light more than other colors.

Closer to the horizon, the sky fades to a lighter blue or white. The sunlight reaching us from low in the sky has passed through even more air than the sunlight reaching us from overhead. As the sunlight has passed through all this air, the air molecules have scattered and rescattered the blue light many times in many directions. Also, the surface of Earth has reflected and scattered the light. All this scattering mixes the colors together again so we see more white and less blue.

What Makes a Red Sunset?

As the Sun gets lower in the sky, its light is passing through more of the atmosphere to reach you. Even more of the blue light is scattered, allowing the reds and yellows to pass straight through to your eyes.

Red sky at sunset

Sometimes the whole western sky seems to glow. The sky appears red because larger particles of dust, pollution, and water vapor in the atmosphere reflect and scatter more of the reds and yellows.



How much of the Sun's light gets bounced around in Earth's atmosphere and how much gets reflected back into space? How much light gets soaked up by land and water, asphalt freeways and sunburned surfers? How much light do water and clouds reflect back into space? And why do we care?

Sunlight carries the energy that heats Earth and powers all life on Earth. Our climate is affected by how sunlight is scattered by forests, deserts, snow- and ice-covered surfaces, different types of clouds, smoke from forest fires, and other pollutants in the air.

MISR (for Multi-angle Imaging SpectroRadiometer) is one of five instruments onboard the Terra satellite. MISR has nine separate cameras that take pictures of Earth's atmosphere and surface from different angles as the Terra satellite passes over a region during its orbit.


Here is something interesting to think about: When you look at the sky at night, it is black, with the stars and the moon forming points of light on that black background. So why is it that, during the day, the sky does not remain black with the sun acting as another point of light? Why does the daytime sky turn a bright blue and the stars disappear?

The first thing to recognize is that the sun is an extremely bright source of light -- much brighter than the moon. The second thing to recognize is that the atoms of nitrogen and oxygen in the atmosphere have an effect on the sunlight that passes through them.

There is a physical phenomenon called Rayleigh scattering that causes light to scatter when it passes through particles that have a diameter one-tenth that of the wavelength (color) of the light. Sunlight is made up of all different colors of light, but because of the elements in the atmosphere the color blue is scattered much more efficiently than the other colors.

So when you look at the sky on a clear day, you can see the sun as a bright disk. The blueness you see everywhere else is all of the atoms in the atmosphere scattering blue light toward you. (Because red light, yellow light, green light and the other colors aren't scattered nearly as well, you see the sky as blue.)



Why is the sky blue?” may seem to be a simple question, but it actually touches some of the deepest aspects of astronomy and skygazing because it deals with light. “Seeing” something whether it’s a table across the room or a galaxy millions of light years away consists of light entering our eyes and the brain taking the light and creating a picture within our brain. So before asking the question “Why is the sky blue?”, it’s necessary to know the answer to the question, “What is light?”
What Is Light?

Light consists of weightless particles (that contain no mass) traveling at about 186,000 miles or 300,000 kilometers per second. These particles of light are called photons. But light also exhibits the characteristics of a wave. Traditionally, wave activity is explained by imagining a pebble being dropped into a lake, but that imaginary lake has been filled with imaginary pebbles years ago. So instead, imagine a long rope tied to the side of a wall and a girl shaking rhythmically one end of the rope up and down. Each up and down shake of the rope is a cycle and the number of cycles per second is the wave’s frequency. If you observe the rope from the side, you will see a wave pattern of alternating crests and troughs. The distance from one crest to another is the wavelength. When the girl shakes the ropes more rapidly, the frequency will naturally increase, but the wavelength will shorten.

Light acts in many ways similarly to the shaking rope. It also has a frequency and a wavelength. As the frequency increases, the wavelength decreases and as the frequency decreases, the wavelength increases. The frequency of light determines its color. Blue light has a higher frequency and a shorter wavelength than red light. Our eyes are sensitive to only a small part of the spectrum of frequencies. There is ultra-violet and infra-red light just beyond our eyes’ range, radio waves with much lower frequencies than light, and gamma rays with much higher frequencies. Sunlight contains many different colors which can be separated through a prism or a rainbow into different colors.

In short, keep in mind the following three facts:

* Light must enter our eyes in order for us to see it
* The Sun emits light with different colors
* Different colored light has different wavelengths

Sunlight and the Atmosphere

The atmosphere around the Earth is largely made up of two colorless gases: oxygen and nitrogen. Red and blue light reacts very different from each other to oxygen. Because the wavelength of blue light is roughly the size of an atom of oxygen, blue light interacts with the oxygen and is scattered by it, while red light, with its longer wavelength, goes right pass the oxygen atoms. If the Earth had no atmosphere, the sun’s light would travel directly from the Sun in a straight line towards our eyes and we would see the Sun as a very bright star in sea of blackness. But because the Sun’s blue light is scattered by the oxygen in the atmosphere, blue light from the Sun enters our eyes from all sorts of different angles and we see the entire sky as blue. The atmosphere scatters violet light even more effectively, but our eyes are more sensitive to blue. Wherever we look towards the sky, some light is bouncing off an oxygen atom and entering our eyes, making the sky appear to be blue.
Sunrise, Sunset

Who hasn’t enjoyed watching a sunset as the Sun’s red disk sinks below the horizon. Why does the Sun now appear red? During sunrise and sunset, the Sun’s light must pass a greater distance through the atmosphere in order to reach our eyes because instead of dropping directly through the atmosphere, it reaches the Earth at an angle. The same scattering effect on the blue light, also takes place, but the blue light is unable to pass through the extra distance and reach our eyes. This leaves only the red light which passes, unhindered through the atmosphere and reaches our eyes in a direct line with little or no scattering. We see the Sun’s disk red because its blue light has been blocked by the atmosphere. We don’t see the entire sky red because there is no scattering and the red light reaches us in a direct line.

Answer 2

The same question twice in a row! This question has been asked over 5000 times, and I've prepared a simple answer, without too much science:

The correct answer is that the blue light is scattered by the air molecules in the atmosphere (referred to as Rayleigh scattering). The blue wavelength is scattered more, because the scatteing effect increases with the inverse of the fourth power of the incident wavelength.
OK, but I've known science graduates who don't understand what this means.
Here's my attempt at an answer without too much physics:

I think most people know that sunlight is made up of light of several different wavelengths, and can be split up into the colours of the rainbow. Blue light has the shorter wavelength, and red the longest wavelength.

When sunlight hits the molecules in the atmosphere, the light strikes the molecules and is absorbed. The molecules vibrate and and give off, or 're-emit' the light. Because the molecules vibrate in all directions, the light is emitted in all directions (called 'scattering'). The molecules in the air are much smaller than the wavelength of visible light, but because the blue wavelength is shorter and more energetic, it reacts much more with the air molecules than the red and yellow wavelengths; which tend to pass straight through.

Because the blue radiation is re-emitted from the air molecules in all directions, it seems to us looking from the ground that the blue light is coming from everywhere; hence the sky seems blue.

Near sunset, because of the low angle of the sunlight, we see more of the red and yellow wavelendth passing straight through, hence the colours of the setting sun.

BTW: The sky isn't blue because of a reflection of the sea; its the other way round, The blue colour of the sea is a little more complicated, because as well as the water molecules scattering the blue light, the water absorbs more of the red and yellow wavelengths, leaving the blue part of the spectrum, as well as part of the green (which is why deep water can appear bluish-green). This effect is even stronger with ice; which results in the intense blue colour we see if we look down a crevasse in a glacier, or down a hole in the snow made by a ski stock..
My thanks to varoius contributers for correcting me on some details.

For a complete, scientific explqanation, look up 'blue sky' in Wikipedia.

Answer 3

6,168 hits.

STOP ASKING THIS!

http://answers.yahoo.com/search/search_result;_ylt=Aq8QV.mwdjS1tLBp2UxfV_UDxgt.;_ylv=3?p=why+is+the+sky+blue


****Wow ssj Rand, if you are going to plagiarize and claim it as your own at least make it a little less obvious you copied and pasted, like removing the authors names and not having it be so freakin' long. We're supposed to believe you typed all that with all the citations and big gaps in spacing and the ads and who is Jacques? Yeah. Nice try.

Answer 4

due to atmospheric refraction of sun light ,the blue color in the spectrum of the white light is refracted the most .so the sky is blue

Answer 5

ssj rand writes a book! ;)
anyone every get bored with a blue sky and green land?

Answer 6

STOP ASKING THIS!

http://answers.yahoo.com/search/search_r...

Answer 7

This is because space is pink and fish are yellow and the moon is blue and noodles are grey and poo is white and this question is stupid.

Answer 8

http://en.wikipedia.org/wiki/Sky

Answer 9

reflection on atmosphere from sun but ssj rand beats me :lol:

Answer 10

Something to do with the ocean.

Answer 11

because of the mixture of gas molecules