No, but it's fairly easy to calculate.
For a P-type (or circumbinary) planet, add the luminosities of the stars (in suns). Take the square root of that, and you have the orbital distance (in AU) where a planet would have the same average insolation as Earth. Divide by the square root of two and you have the minimum distance for habitability (requires a weak greenhouse effect). Multiply by the square root of two and you have a good outer limit (requires a fairly strong greenhouse effect). However, the outer limit is much fuzzier, especially when you take into account geologic sources of heat.
For an S-type planet (orbiting only one of the stars) the more distant star will have a negligible effect on a planet's climate; for stars of similar luminosity, the secondary star will contribute AT BEST 10% the insolation of the primary... and this is for a system on the edge of stability. For Alpha Centauri, a habitable planet of either star would receive less than 1% the energy Earth recieves from the sun from the other star.
The only time you need to take into account the luminosities of both stars for determining the temperature of an S-type planet is if the secondary star is much more luminous than the primary. For main sequence stars with a long enough lifespan to develop life, this means that the primary star must be an M-class. In such a case, calculate radiation from the primary based on the average distance from the planet to the primary, and calculate radiation from the secondary based on the average distance from the primary to the secondary. Add these to get the planet's average insolation.
Topic: Habitable zone for a Binary Star System (Read 3059 times)
