Two large moons can't orbit a planet, so unfortunately you could only have a binary planet pair. Humans would actually fare better on a bigger planet with a bigger atmosphere, we just wouldn't evolve there because conditions would be much better for all the life on that planet. The ideal planet would be about 4 earth masses, a bit more dense than Earth, have a heavy atmosphere at least several times greater than ours, and have a large moon with a tiny atmosphere, it should also rotate rapidly so that more of the planet can get covered with storms, or it could have massive amounts of land but a lot of it would go to waste as potential seasonal ice caps or deserts, it would still contain more habitable land than the current Earth simply due to the sheer size of the planet. It would also be a bit warm, perhaps with an average temperature between 20C and 25C, simply to increase the heat flow between the tropics and the polar regions so that they don't develop ice caps and we can settle the entire world, albeit with mandatory air conditioning between 20N and 20S, or restrict ourselves to the higher spaces of land where it doesn't reach 40-50C in the summer.
Topic: Terra forming worlds (Read 1753 times)
