Why is the Sky Blue and why are Sunsets Red?

The blue hue of the sky is the first thing you see when you gaze out into a clear day. People have been asking the question "why is the sky blue?" since the beginning of humankind. Although this question is not the most advanced scientific question of today, it is something interesting to think about.

Image result for coloured light wavelengths
The colours of the spectrum are made up of white light. Light travels in straight lines unless it is interrupted. (separated, scattered, reflected, refracted) Different colours of the spectrum have different wavelengths, red, having the least amount of frequency and long wavelengths to violet, high frequency and short wavelengths.




Particles in the atmosphere like dirt scatter light upon contact. Blue light has short wavelengths, allowing it to interact with more particles. For example, when a beam of sunlight hits a dirt particle in the air, blue light separates from white and will scatter around the atmosphere.


Why isn't the sky violet? Violet has a frequency even higher than blue. The sun emits less violet than blue light. Furthermore, human eyesight is more sensitive to blue, allowing our eyes to see more blue than violet.






If the sky is blue, then what about the sunset when the horizon becomes this blend of warm colours?The sunset is red because when the sun sets, the particular angle has more atmosphere for light to travel through, taking longer. This allows reds, oranges, and yellows to pass through while the blues scatter elsewhere.

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