Effective Temperature

Although stars are not perfect blackbodies, they can be approximated as such, allowing us to calculate their surface temperature via the Stefan-Boltzmann Law:

$ L = 4 \pi R^{2} \sigma T^{4}_{e} $ where $ L = $ luminosity of the star
$ R = $ star’s radius
$ \sigma = $ Stefan-Boltzmann constant
$ = $ $ 5.67 \times 10^{-8} W m^{-2} K^{-4} $
$ T_{e} = $ effective temperature

The surface temperature, calculated by assuming a perfect blackbody radiating the same amount of energy per unit area as the star, is known as the effective temperature of the star.


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