The
density of stars
near the centre is a hundred million times as
great as it is in the neighbourhood of the Sun, says Ted Lauer of the National Optical Astronomy Observatories in Kitt Peak, Arizona.
So it's all gases at
greatest density will be doing the same thing around the planet at the same time (*) and as these change with differences in
density in the play between gravity and pressure and kinetic and potential from
greatest near the surface to more rarified, less dense and absent any kinetic to write home about the higher one goes, then, energy conservation intact, the hotter will rise and cool because losing kinetic energy means losing temperature, thus cooling they which began with the closest in
density and kinetic energy as a sort of band of brothers
near the surface will rise and cool at the same time whereupon they'll all come down together colder but wiser that
great heights don't make for more comfort and giving up their heat will sink displacing the hotter now in their place when they first went travelling.