I was trying to put together an idea for a Gas Giant like planet that could possibly support some kind of fairly complex life, and I hit upon a few ideas:
-Located in a habitable zone roughly similar to Earth
-Composition and Structure roughly similar to Neptune or Uranus
The basic idea here is that Jupiter and Saturn are almost entirely comprised of Hydrogen and Helium, have a really high internal temperature and massive pressure, not conductive to much!
Now I don't know if Uranus or Neptune are really different enough for this to be plausible but it seems worth a shot to consider, so here is the idea I'm forming that anyone is free to shoot down.
Since this hypothetical planet is roughly the same as Neptune and Uranus in chemical composition then it means large amounts of water Ice, Methane and Ammonia form the bulk of the planet, perhaps creating a massive Ocean like I've seen proposed for some such planets in their star's habitable zone. This sounds like a nice base to build off of in forming life and its relatively close proximity to the sun could keep its outer layers nice and balmy.
But I don't know if life can really develop without a clear surface, or if the temperatures and pressures would still be too much of a problem (I understand that Uranus has a cooler core than the rest so I though I could do something with that but its still seems to be thousands of degrees Celsius so maybe not). I guess different forms of life could develop adapted to the different strata and the temperature, makeup and pressure until it gets too close to the core, but I don't know if all the organic matter would just eventually get mashed into the superhot core where it could be no longer used (would some kind of internal convection get around this?).
Next I was wondering if Photosynthesis is really possible here, assuming that nature can't produce a creature that would float in the upper Hydrogen/Helium portions of the Atmosphere that would limit life to places down where denser, heavier clouds begin, would enough sunlight penetrate that deep to be useful? If not, could I simply make it so there's less light gases so the distance between life and the sun isn't so bad? (maybe much of the light gases are blown off by its relative proximity to the sun?) Or could life subsist off of internal heat, chemical energy and electrical storms?
Finally, in terms of actual life would huge balloon animals really be possible like Carl Sagan proposed or would that stretching things too far?
Thanks to anyone who reads this and answers!