The temperature of stars other than the Sun can be approximated using a similar means by treating the emitted energy as a black body radiation. So: L = 4 π π R 2 σ σ T 4 where L is the luminosity, σ is the Stefan–Boltzmann constant, R is the stellar radius and T is the effective temperature. This formula can then be rearranged to calculate the temperature: T = L 4 π π R 2 σ σ 4 or alternatively the radius: R = L 4 π π σ σ T 4