Why might a planet orbiting at the exact calculated distance of the HZ still be too cold for liquid water?
Answer
It possesses a very thin, tenuous atmosphere resulting in low surface pressure.
A planet with insufficient atmospheric pressure acts effectively outside the outer boundary because the pressure is too low to support water remaining liquid, even if the orbital distance is correct.
Related Questions
What is the common nickname for the Habitable Zone?What occurs if a planet orbits too close to its star within the context of water state?What essential role does atmospheric pressure play in maintaining surface liquid water?On what primary characteristic of a star is the location of the Habitable Zone entirely dependent?What geological process is cited as essential for buffering a planet's climate over the long term?Why might a planet orbiting at the exact calculated distance of the HZ still be too cold for liquid water?What planetary attribute is required to hold onto a life-enabling atmosphere over cosmological timescales?What is the primary reason that subsurface oceans, like those hypothesized on Europa, are not dependent on the classical Goldilocks Zone?What must astronomers calculate first when searching for exoplanets around a specific star?What is the crucial secondary filter that means HZ location does not guarantee liquid water?How is the concept of the Habitable Zone refined into a three-dimensional model called the 'Habitability Bubble'?