Astronomy 123 Basics
Blackbody Radiation
A blackbody radiator is a perfect radiator of light
that absorbs and re-emits all radiation incident on it.
Its light output depends only on its temperature.
The sun and stars emit radiation like a blackbody following
the
Blackbody
spectrum.
As an object (a blackbody) is heated, the radiation it
emits will always be described by the
blackbody
spectrum for the temperature of the body, with the curve peaking to
higher and higher frequency.
Wien's Law
The maximum wavelength of radiation emitted by a blackbody
is inversely proportional to the temperature:
max wavelength ~ 1/Temperature
Stefan's Law
The total amount of energy emitted by a blackbody
is proportional to the 4th power of the temperature:
Wien's Law and Stefan's Law are evident in the changes
in the
blackbody
spectrum with temperature.
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