Circumbinary planet

A circumbinary planet orbits both members of a binary star rather than just one. If its orbital radius greatly exceeds the binary separation, the stellar contributions to irradiation add approximately as luminosities at a common distance.

For blackbody stars of radii $R_A,R_B$ and temperatures $T_A,T_B$, a distant circumbinary planet with Bond albedo $A_B$ and uniform global reradiation has planetary equilibrium temperatureThis neglects internal cooling, eccentricity, and corrections from finite binary separation. The stars heat the planet through the sum of their absorbed bolometric fluxes, not an average of their temperatures.