New Estimates for the Probability of a Runaway Greenhouse

Whether a planet is able to avoid a “runaway greenhouse” fate strongly depends on how close it is to the inner edge of its star’s habitable zone. New work by VPL researchers shows that less thermal radiation may be required for a planet to trigger this process than was previously thought. This suggests that the habitable zone could be narrower than we think, and that planets must be further from their stars to be considered hospitable for life.