Why is the sky blue?
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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.
only a little of the red, orange & yellow light is affected by the air.

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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
Black sky in space


no matter were you look in the sky, it is blue. This blue light comes from the Sun when it was bounced around in the sky lots of times, and eventually reached your eyes. and at sun sets you see the other end of the atmosphere where the red light rays have passed and that's when the sky goes red.

Sunlight interacting with the Earth's atmosphere makes the sky blue. In outer space the astronauts see blackness because outer space has no atmosphere.
Sunlight consists of light waves of varying wavelengths, each of which is seen as a different color. The minute particles of matter and molecules of air in the atmosphere intercept and scatter the white light of the sun. A larger portion of the blue color in white light is scattered, more so than any other color because the blue wavelengths are the shortest.

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.
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