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quite a few of those are not relevant for habitability. for example tides, really? or you wouldn't survive if day would have 40 hours???



I think it's more like if the day was 100 msec that you have to worry about. Also, if the day is too slow, then one side of the planet bakes while the other side freezes. Think of the rotation axis as a spit roaster.


Nice metaphor :)


They are relevant, you're just misinterpreting. None of these are meant to imply "X must be like Earth for the planet to be habitable," they mean "X is an important factor for habitability and must be considered in our models if we want them to be meaningful, unlike the ESI which captures a mere handful of variables".

For example, "tidal habitable zone" doesn't mean "we need [ocean] tides to survive," it means "tidal heating effects have an enormous impact on planetary conditions". For example, an Earth analogue in orbit around a tiny red dwarf in a seemingly "habitable zone" would be subject to tidal heating effects which would bake the surface, whereas a similar planet in a similar orbit around a sun-like yellow dwarf would not.

Similarly, "rotation rate habitable zone" doesn't mean "the planet must have a ~24 hour day", it means "all else being equal, a planet's rotation rate can greatly affect habitability," mostly due to weather patterns and air/heat circulation. By including rotation rate in our models, some planets previously thought to be inhabitable may turn out not to be, and vice versa.




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