Quote Himself (
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We could probably (factoring in gravity) bring the pressure minimum down to 0.7 or 0.8, considering people on Earth can live comfortably at high elevation.
As to tidally locked planets, one potential problem is that the sun-facing side could end up drying out as the moisture is gradually locked away in the ice sheet on the night side.
you're right, people can survive pressure 0.7 or 0.8, however, does not seem like an impossible challenge this ....