. You do know that Mars is a planet in our solar system, right? - the figures published by the primary source author are similar to the same data for Mars, and Mars is right here in our own solar system. Just because they failed to make the comparison doesn't mean we can't, you completely missed the discussion at Gliese 581 c and the precedent to good article writing that is there, for your own stubborn bias. The comparison using the Earth's Green house gas effect is speculation by the discovery team since no one knows the atmosphere of Gliese 581 g, are you aware this is speculation?? We don't need to provide you with a reference that says the sky is above the ground, their calculations of temperature are directly comparable to the temperatures of Mars. That's just good writing