Why do sunsets appear red and orange?
Show answer & explanation
Answer: Atmosphere scatters blue light away
Sun changes color at end of day — Wrong. The sun's light doesn't change color. Sunsets appear red because Earth's atmosphere scatters shorter wavelengths, leaving longer red/orange light.
Atmosphere scatters blue light away ✓ — Correct! At sunset, sunlight travels through more atmosphere (longer path). Rayleigh scattering preferentially scatters shorter wavelengths (blue, violet) away from your line of sight. Longer wavelengths (red, orange, yellow) pass through more easily. Result: the sun and sky near it appear red/orange. Same physics makes the sky blue (scattered blue light) during the day!
Horizon reflects Earth's heat — Wrong. Horizon doesn't reflect heat as color. Red sunsets result from atmospheric scattering removing blue light, leaving red/orange wavelengths.
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