Why is the sky blue? The science behind the sky's color

Why is the sky blue, you ask?

Rayleigh scattering, a phenomenon, is the reason the sky is blue. When sunlight interacts with the minuscule air molecules in the Earth's atmosphere, scattering takes place. All the hues of the rainbow are present in sunlight, but blue light is scattered more than the other colors due to its shorter wavelength.

When sunlight enters the atmosphere, the air molecules scatter the blue light in all directions. When we look up at the sky, we see this strewn blue light. Although not as much as blue light, the other colors of light are also scattered. The daytime sky seems blue because of this.

The amount of atmosphere that sunlight must pass through to reach our eyes increases at sunrise and dusk. The majority of the blue light has been dispersed by the time the sunshine reaches us. The sky appears red, orange, and yellow because of this at sunrise and dusk.

Even during the day, there wouldn't be any air molecules in the Earth's atmosphere, therefore the sky would appear completely black. This is due to the absence of anything to scatter sunlight.

A more thorough description of Rayleigh scattering is provided below:

Since Rayleigh scattering is a form of elastic scattering, the light's wavelength is unaffected by scattering. The light's wavelength and the size of the scattering particles both affect how much scattering occurs. Light with shorter wavelengths scatters more than light with longer wavelengths.

The wavelength of visible light is substantially larger than the size of the air molecules in the Earth's atmosphere. This means that all hues of visible light are dispersed by the air molecules, but the shorter wavelength blue light is scattered more.

The angle at which the light is scattered affects how much scattering as well. More light is scattered when it is reflected directly back at the observer than when it is reflected from other angles. The sky appears brighter immediately overhead than it does closer to the horizon because of this.

Why isn't the sky purple?

Violet light should be more scattered because it has a shorter wavelength than blue light. Our eyes are more sensitive to blue light than violet light, though. Additionally, the upper atmosphere absorbs some of the violet light. Because of this, the sky appears blue rather than violet.

Conclusion

Rayleigh scattering is the cause of the sky's blue color. When sunlight interacts with the minuscule air molecules in the Earth's atmosphere, scattering takes place. Due to its shorter wavelength than the other colors, blue light is scattered more than the others. We can see the strewn blue light in the sky when we gaze up.