Astrophysics (index) | about |

The **Planck Function** is
a function of Wavelength and Temperature that
describes the spectral Radiance at each wavelength in
Black-Body Radiation.

- B(ν,T) - spectral radiance (specific Intensity).
- ν - wavelength.
- h - Planck Constant.
- T - temperature.
- c - speed of light.
- k
_{B}- Boltzmann Constant.

2hν^{3}1 B(ν,T) = ———— ——————————— c^{2}e^{hν/(kBT)}- 1

Radiance is the quantity of radiation emitted through a surface into a given Solid Angle, spectral radiance being the radiance at a given wavelength.

Black-Body Radiation