Why is

Описание: Why is Sky blue during Daytime?    • Why is the Sky Blue? Why is #Sea #blue?  

Each color can be thought of as a light wave with a different wavelength (or size). Within the small range of wavelengths (or colors) that we can see with our eyes, the shorter waves are blue and the longer ones are red. Colors such as green, yellow, and orange lie in between the blue and red ends of the visible spectrum.

When light comes from the sun, all these light waves of different wavelengths travel through empty space.

When they reach Earth’s atmosphere, primarily made up of gas molecules, with oxygen comprising about 21% and nitrogen about 78%. In addition, water molecules in the form of droplets, ice crystals, and vapour, and particles such as dust, pollutants, and ash can be found in the atmosphere, which is denser closer to the Earth and thins out as the altitude increases.

Scattering affects the color of light coming from the sky, but the details are determined by the wavelength of the light and the size of the particle.

When light interacts with our atmosphere it can scatter, similar to the way one billiard ball can collide with another, making them go off in different directions. The main form of atmospheric scattering is known as Rayleigh scattering.

Particles that are small (tiny gas molecules that make up our Earth’s atmosphere (mostly oxygen and nitrogen) compared with the light wavelength scatter blue light more strongly than red light. Within the visible range of light, red light waves are scattered the least by atmospheric gas molecules.

The Sun's rays have to travel a shorter path through Earth's atmosphere in the day. This is why the sky looks blue during the day. When you look up at the sky during the day, this scattered blue and violet light reaches your eyes, however, the human eye is more receptive to blue frequencies than violet frequencies, so the sky looks blue.

During sunsets and sunrises, when the Sun is closer to the horizon, sunlight has to travel through a longer distance and thicker amount of atmosphere to reach an observer’s eye. Due to Rayleigh scattering, most of the light of shorter wavelengths – the blue, violet, and green – are scattered away multiple times, leaving only lights of longer wavelength – the red, orange, and yellow – to pass straight through to the observer.
Loss of energy due to scattering is more for high frequency wave. Longer wavelength wave has minimum loss due scattering, and can travel long distance. Red color has longer wavelength, its intensity reach to the observer is more compare to other colors.
This is why a rising and setting Sun tends to take on spectacular hues of red, orange, and yellow.