Blue sky

Blue Sky is a natural phenomenon that is observed during clear weather conditions. The sky appears to be blue due to a process known as Rayleigh scattering.

Overview

The color of the sky is primarily determined by the scattering of sunlight by the atmosphere. The blue color of the sky is the result of a particular type of scattering called Rayleigh scattering. The sun emits light in all directions and the blue light is scattered in all directions by the tiny oxygen and nitrogen molecules in Earth's atmosphere. Blue is scattered more than other colors because it travels in smaller, shorter waves. This is known as Rayleigh scattering.

Rayleigh Scattering

Rayleigh scattering, named after the British scientist Lord Rayleigh, is the predominantly elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation. For light frequencies well below the resonance frequency of the scattering particle, the amount of scattering is inversely proportional to the fourth power of the wavelength.

Blue Sky and Sunsets

The blue color of the sky is not the only atmospheric color phenomenon that can be explained by Rayleigh scattering. Sunsets often appear red, orange, pink, or purple because the sun is lower in the sky and the light must pass through more of the Earth's atmosphere. This phenomenon is known as the Tyndall effect.

Cultural Significance

The blue sky has been a source of inspiration and symbolism in many cultures around the world. It is often associated with freedom, imagination, and inspiration in popular culture and literature.

See Also

• Rayleigh scattering
• Tyndall effect
• Color of water
• Diffuse sky radiation