Celestia Forums

I want to know if there's an equation that allow me to know the mean temperature of a planet calculating atm. pressure, air composition, the distance to the star, and star type.

Example: Marduk have atm. pressure of 10atm, air composition is 85% N2 and 25% methane and is orbiting a M0V star at 2 AU.

Is there an equation to do these things?

I saw that some people saw my question, but nobody still asked me any equation. I need it because it will be very important to make my Audbeyon add-on in Andromeda galaxy.
I want to make the environments more "realistic" or at least pseudo-realistic as possible. I want to make carbon worlds ( with complex life )with thick atmospheres that have methane in high concentration at the right distances to the stars to be not too hot or cold. So for that I'll need some equations to help me, or at least a program that can do these calculations for me.