Wien's Displacement Law

Radiation · 1893

Equation: λ_max·T = 2.898×10⁻³ m·K
Field: Radiation
Named After: Wilhelm Wien
Symbols: λ_max wavelength where a hot body glows brightest · T its absolute temperature · the product is a constant
Year: 1893

Significance

Hotter things glow bluer: peak wavelength slides inversely with temperature. A 5,800 K Sun peaks in the green-yellow, a 3,000 K ember in the infrared, and the 2.7 K afterglow of the Big Bang peaks at a millimetre — the cosmic microwave background, read straight off this law.

Minerals

Corundum

Timeline

Photon Decoupling — the CMB The Sun Dies

Celestial Objects

Sun

Theories

Quantum Hypothesis

Stefan–Boltzmann Law Hubble's Law Cosmological Redshift Planck's Law Saha Ionization Equation

Instruments

Planck Satellite James Webb Space Telescope (JWST)

Constants

CMB temperature Wien displacement constant Planck constant

Spectral Types

Y-type Stars (Y Dwarfs)T-type Stars (T Dwarfs)K-type StarsB-type StarsM-type StarsG-type StarsA-type StarsL-type Stars (L Dwarfs)F-type StarsO-type Stars