Mars is a lethal desert, but it has gravity, some atmosphere, and water, making it better than most places for a species with our current level of technology.

Mars is a lethal desert, but it has gravity, some atmosphere, and water, making it better than most places for a species with our current level of technology. Floating cities in the atmospheres of gas giants, or underwater cities on ice moons might be better long term, but we can't do that sort of thing yet. Life may be rare and unusual, we need to ensure it does not end with Earth.