Astrophysics (index)about

black-body radiation

(thermal emission, thermal radiation)
(continuous spectrum characteristic of the temperature of a body)

Black-body radiation (thermal emission or thermal radiation) is electromagnetic radiation within and surrounding a body in thermodynamic equilibrium at a constant, uniform temperature. This produces a continuous spectrum (a continuum emission, the black-body spectrum) whose shape is dependent only on the temperature of the body.

Planck's law (Planck function) describes the spectrum:

I(ν,T) = 2hν3/c2 × 1/(ehν/(kT)-1)

The above equation represents an ideal case, i.e., assuming the thermodynamic equilibrium and uniform temperature, but all materials produce radiation associated with their temperature, perhaps rightly called thermal emission or thermal radiation, and informally, black-body radiation. The ideal case and its equation represent a useful first approximation.


Referenced by:
atmospheric temperature profile
black body (BB)
ionized carbon fine structure line ([CII])
circumstellar disk
cosmic microwave background (CMB)
cold gas
Compton scattering
continuous spectrum
continuum emission
eclipse mapping
effective temperature (Teff)
Europa Clipper
foreground subtraction
infrared (IR)
Kelvin-Helmholtz mechanism
Mars Global Surveyor (MGS)
obscured fraction-luminosity relation
1.3mm observation
Planck function
power law
protoplanetary disk (PPD)
Rayleigh-Jeans law
radiative forcing (RF)
secondary eclipse
spectral energy distribution (SED)
star formation rate (SFR)
shock wave
submillimeter galaxy (SMG)
spectral index (α)
stellar parameter determination
stellar temperature determination
synchrotron radiation
synthetic photometry
thermodynamic equilibrium (TE)
ultraluminous infrared galaxy (ULIRG)
Very Small Array (VSA)
Wien's displacement law
X-ray source (RS)
Yarkovsky effect
Yarkovsky-O'Keefe-Radzievskii-Paddack effect (YORP)