General Knowledge · 2
Why is the sky blue?
Answer
Blue light waves scatter more than other colors
The sky appears blue because of Rayleigh scattering. Shorter blue and violet wavelengths of sunlight scatter more readily in the atmosphere than longer red and yellow wavelengths. We see blue rather than violet because violet is absorbed higher in the atmosphere.
💡 Did you know?
Rayleigh scattering is why sunsets appear red—the blue light scatters away, leaving longer red wavelengths to reach your eyes.
Other options people guess
- Water in the atmosphere is blue
- The sun emits blue light
- The Earth's magnetic field makes it blue
Topics
- physics
- optics
- light
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