Why is the sky blue.?

Answer 1

The light we have here on Earth comes from the Sun. Sunlight looks white, but is actually a mixt ure of all of the colors of the rainbow. When sunlight strikes air particles (which are very small), the light itself is scattered in all directions, forward, sideways, and backwards.

Air molecules scatter some colors of light better than others. Blue light is scattered the most and red light is scattered the least. In fact, blue light is scattered at least 10 times more than red light. Since the blue rays of lights are scattered the most, they reach our eyes from all directions and we see more blue than any other color. This makes the sky look blue.

Answer 2

The Earth's sky is blue because the air molecules (largely nitrogen
and oxygen) are much smaller than the wavelength of light. When light
encounters particles much smaller than its wavelength, the scattered
intensity is inversely proportional to the 4'th power of the
wavelength. This is called "Rayleigh scattering," and it means that
half the wavelength is scattered with 2**4 = 16 times more intensity.
That's why the sky appears blue: the blue light is scattered some 16
times more strongly than the red light. Rayleigh scattering is also
the reason why the setting Sun appears red: the blue light has been
scattered away from the direct sunlight.

Thus, if the atmosphere of another planet is composed of a transparent
gas or gases whose molecules are much smaller than the wavelength of
light, we would, in general, also expect the sky on that planet to
have a blue color.

If you want another color of the sky, you need bigger particles in the
air. You need something bigger than molecules in the air---dust.

Dust particles can be many times larger than air molecules but still
small enough to not fall out to the ground. If the dust particles are
much larger than the wavelength of light, the scattered light will be
neutral in color (i.e., white or gray)---this also happens in clouds
here on Earth, which consist of water droplets. If the dust particles
are of approximately the same size as the wavelength of light, the
situation gets complex, and all sorts of interesting scattering
phenomena may happen. This happens here on Earth from time to time,
particularly in desert areas, where the sky may appear white, brown,
or some other color. Dust is also responsible for the pinkish sky on
Mars, as seen in the photographs returned from the Viking landers.

If the atmosphere contains lots of dust, the direct light from the Sun
or Moon may occasionally get some quite unusual color. Sometimes,
green and blue moons have been reported. These phenomena are quite
rare though---they happen only "once in a blue moon...." :) The dust
responsible for these unusual color phenomena is most often volcanic
in origin. When El Chicon erupted in 1982, this caused unusually
strongly colored sunsets in equatorial areas for more than one year.
The much bigger volcanic explosion at Krakatoa, some 110 years ago,
caused green and blue moons worldwide for a few years.

One possible exception to the above discussion is if the clouds on the
planet are composed of a strongly colored chemical. This might occur
on Jupiter, where the clouds are thought to contain sulfur, phosphorus,
and/or various organic chemicals.

It's also worth pointing out that the light of the planet's primary is
quite insignificant. Our eyes are highly adaptable to the dominating
illumination and perceive it as "white," within a quite wide range of
possible colors. During daytime, we perceive the light from the Sun
(6000 K) as white, and at night we perceive the light from our
incandescent lamps (2800 K, like a late, cool M star) as white. Only
if we put these two lights side-by-side, at comparable intensities,
will we perceive a clear color difference.

If the Sun was a hot star (say of spectral type B), it's likely we
still would perceive its light as "white" and the sky's color as blue

Answer 3

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.

Answer 4

The sky appears blue to us on a clear day, because the atoms of nitrogen and oxygen in the atmosphere separate the suns white light into its many colors, and scatter them throughout the atmosphere.

The wavelength of the blue light scatters better than the rest, predominates over the other colors in the light spectrum, and makes the sky appear blue to us.

The scientific name for this phenomenon is the Tyndall effect, more commonly known as Rayleigh scattering.

This phenomenon describes the way in which light physically scatters when it passes through particles in the earths atmosphere that are 1/10th in diameter of the color of the light. The light spectrum ranges in wavelength from red to violet, and, since the wavelength of the blue light passes through the particles with greater ease than the wavelengths of the other colors of light, the sky appear blue to the naked eye.

The human eye has three types of light receptors, known as cones, located in the retina. The cones are either considered to be red, or blue, or green, based upon their strong response to light at these wavelengths. As light stimulates these receptors, our vision translates the signals into the colors we see.

When gazing at the sky, the red cones respond to the small amounts of red light scattered, and even less strongly to the orange and yellow wavelengths. Although green cones respond to yellow, their response to scattered green and green-blue wavelengths is stronger. Finally, colors near the strongly scattered blue wavelengths stimulate the blue receptors.

In short, the skylight stimulates the red and green cones almost equally, while stimulating the blue cones more strongly. For these reasons, our vision naturally adjusts as clearly as possible to separate colors

Answer 5

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 first steps towards correctly explaining the colour of the sky were taken by John Tyndall in 1859. He discovered that when light passes through a clear fluid holding small particles in suspension, the shorter blue wavelengths are scattered more strongly than the red. This can be demonstrated by shining a beam of white light through a tank of water with a little milk or soap mixed in. From the side, the beam can be seen by the blue light it scatters; but the light seen directly from the end is reddened after it has passed through the tank. The scattered light can also be shown to be polarised using a filter of polarised light, just as the sky appears a deeper blue through polaroid sun glasses.
This is most correctly called the Tyndall effect, but it is more commonly known to physicists as Rayleigh scattering--after Lord Rayleigh, who studied it in more detail a few years later. He showed that the amount of light scattered is inversely proportional to the fourth power of wavelength for sufficiently small particles. It follows that blue light is scattered more than red light by a factor of (700/400)4 ~= 10.
~OR~
Transmitted light (from the sun, light bulbs, fire, etc) is made up of a spectrum of colors. The longest wavelengths of light are on the red end of the spectrum and the shortest wavelengths are on the blue/violet end of the spectrum.
When transmitted light such as sunlight enters our atmosphere it collides with the oxygen and nitrogen atoms. The color with the shorter wavelength is scattered more by this collision. Because violet and blue are the shortest wavelengths the sky appears to be violet / blue. But because our eyes are more sensitive to blue light than they are violet light, we perceive the sky as blue
~OR~

Answer 6

It has to do with the wave lengths of light. White light coming from the sun has all the visible wave lengths in it (red is longest, blue is shortest). The longer wave lengths get absorbed in the atmosphere but the blue wave lengths are reflected and thus made visible.

Answer 7

the sky is not blue, it's only the reflection of the bodies of water in the earth's surface which causes it to turn blue..

Answer 8

because the person who put names to colours was a liar he got them mixed up..... the sky is actualy black the same as space just the sun's ultra voilet rays that makem look blue....
by the way who said that the person who named all the colours has got them right

Answer 9

same reason why we have Blue Mondays.

>>> refraction of Blue Light by gases and other molecules in space >>>>>

Answer 10

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