Got your point but the concept of habitable zone or most suitable condition for a life to form on a planet, what is it exactly? Because we are nearer to the sun and the amount of sunlight, the presence of water, atmosphere, humidity (and other earthly condition) is exactly favourable for the kind of life form that is present here on earth...but lets suppose a planet far far away..extremelyy cold and very different from earth ..would not there be any chance that the planet is habitable to completely different form of species that does not need heat, atmosphere or water to survive unlike we earthian?