The results of the latest analysis are not entirely reassuring.
Sometime in the last few billion years, disaster struck one of Earth's nearest neighbours. Planetary geologists think there is good evidence that Venus was the victim of a runaway greenhouse effect which turned the planet into the boiling hell we see today.
A similar catastrophe is almost certain to strike Earth in about 2 billion years, as the Sun increases in luminosity.
But that raises an important question: is it possible that we could trigger a runaway greenhouse effect ourselves by adding carbon dioxide to the atmosphere?