On my worldbuilfing project, I changed the planet to 7400 km rad and added some Jovian stresses to make sure the planet has enough "umph" for techtonic activity thru 6.5 Gy of age so I can get ammonia/methane sentience

anyways.. with the planet and density, I have a mass of ~1.64 and so doing a doable atmosphere of ~1.966

But I was also getting a more agressive and thereby rare heavier atmosphere which would lead me to ~4.915 atm

BUT, due to tidal lock, the magnetic field is still .006, and so I feel that the heavier atmosphere would lead to a better avoidance of loss due to stellar wind.

now for another issue.. What kind of heat would an atmosphere this thick produce... I know it's only a Titan like N2/CH4 one, but still, the heat must be impressive...

Difficult to say--I'm no atmospheric physicist, but I'm guessing that insolation and albedo will factor heavily in the final equation, as will the transparency of the atmosphere.

If the insolation were similar to Earth, and the percentage of methane were say 5-10%, I'm guessing the temperature would be *very* hot, especially if there's also water vapor; methane is a much more potent greenhouse gas than carbon dioxide.

__________________
"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

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