A measure of the intensity of a region of the sky, based on the temperature of a black body that would emit radiation of the observed intensity at the given observing frequency. Frequently computed in radio astronomy using the Rayleigh-Jeans approximation, in which case it is directly proportional to the intensity per unit area. For thermal emission mechanisms, it may correspond to a physical temperature in an emitting region.
The temperature of a blackbody radiating the same amount of energy per unit area at the wavelengths under consideration as the observed body.
The temperature an object/surface appears to have when measuring the intensity of its emitted radiation at a particular frequency/wavelength.
The measured temperature of a surface over a specific wavelength region in the electromagnetic spectrum.
The temperature an object must have to produce the observed intensity.
the apparent temperature of a celestial object, based on the assumption that it radiates as a blackbody
The Planck temperature associated with the radiance for a given wavelength.
Temperature of a blackbody that gives the same radiance in a narrow range of wavelengths as the object being studied.
A descriptive measure of radiation in terms of the temperature of a hypothetical blackbody emitting an identical amount of radiation at the same wavelength. The brightness temperature is obtained by applying the inverse of the Planck function to the measured radiation. Depending on the nature of the source of radiation and any subsequent absorption, the brightness temperature may be independent of, or highly dependent on, the wavelength of the radiation.
Brightness temperature is a measure of the intensity of radiation thermally emitted by an object, given in units of temperature because there is a correlation between the intensity of the radiation emitted and physical temperature of the radiating body which is given by the Stefan-Boltzmann law.