Mie Scattering — Why the Sky is Blue & Sunsets Red

Scattering efficiency Q_sca vs size parameter x = 2πr/λ for a dielectric sphere. Small particles (x≪1): Rayleigh regime Q∝x⁴ — blue scattered strongly. Large particles: Mie oscillations → wavelength-independent (white clouds, red sunsets).

Refractive index n: 1.50 Particle radius r (nm): 50 Show wavelength: 550 nm

Hover over the Q_sca plot to explore