The scattering of light by particles in the atmosphere, such as air molecules, clouds, dust, and smoke, is known as Rayleigh scattering. Rayleigh scattering is more effective for shorter wavelengths, such as blue and violet, compared to longer wavelengths like red. This phenomenon is explained by the interaction of light with the particles in the atmosphere.
The scattering of light depends on the size of the particles relative to the wavelength of the light. When light interacts with particles that are smaller than the wavelength, as is the case with air molecules and other atmospheric particles, Rayleigh scattering occurs. The scattering intensity is inversely proportional to the fourth power of the wavelength.
Blue light has a shorter wavelength than red light, which makes it more susceptible to Rayleigh scattering. The smaller particles in the atmosphere scatter shorter wavelengths more efficiently due to their size relative to the wavelength of blue light. As a result, the blue light gets scattered in all directions, including sideways and backward toward the observer, leading to a blue color appearance in the sky.
In contrast, red light with its longer wavelength is less affected by Rayleigh scattering in the Earth's atmosphere. It is scattered to a lesser extent compared to blue light, allowing more of the red light to pass through the atmosphere without significant scattering. This is why during sunrise and sunset, when the sun is closer to the horizon, the path length through the atmosphere is longer, and more of the shorter-wavelength blue light gets scattered, resulting in the reddish hues observed during those times.
Overall, the scattering of blue light is more pronounced than red light in the Earth's atmosphere due to the phenomenon of Rayleigh scattering, where smaller particles in the atmosphere interact more effectively with shorter wavelengths of light.