# Local surface warming on a rogue planet [closed]

There have been several previous questions about geothermal warming of a rogue planet with regard to depth: how much overlying atmosphere, water, rock do you need for a given geothermal flux to maintain a livable temperature (potentially across the entire globe). I'm asking instead about local surface heating. Specifically:

A rogue planet has atmospheric composition same as Earth.

There is a lake 1 km wide whose surface is maintained at 20 Celsius by geothermal heat flux. (The required heat flux would probably be larger than exists anywhere on Earth today. I'm okay with that.) This will have a warming effect on the air in the vicinity of the lake.

How far from the lake, will the air temperature 2 m above the ground, still be at least -60 Celsius? (I'm using that as a proxy for 'humans can walk around in suitable protective clothing instead of needing an oxygen mask'.)

• You're leaving out a lot of relevant details. What is the temperature of the ground surrounding the lake? What is the pressure of the atmosphere? What is the composition of the atmosphere? Depending on the mix of gasses humans have worked at pressures as low as 30 kPa to as high as 7026 kPa. Both pressure and gas mix will have an impact on conductivity. Oct 6, 2023 at 21:01
• @sphennings: A rogue rocky planet has no atmospheric composition at all, because all the air is frozen solid covering the surface. The atmospheric pressure is zero. Oct 6, 2023 at 21:02
• If there's no atmosphere how can humans walk around in suitable protective clothing instead of needing an oxygen mask? Oct 6, 2023 at 21:03
• Also if there's no atmosphere what are you measuring the temperature of 2m above the surface? Oct 6, 2023 at 21:05
• Also if there's no atmosphere, a liquid lake would boil. Oct 6, 2023 at 22:46