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Here are some reasons:


- Red dwarfs are by far the most common type of star in the Milky Way, at least in the neighbourhood of the Sun

- Red dwarfs exist for a long time (longer than ten billion years) which gives life a long time to spring into existence (or start via panspermia) and evolve

- Planets in the habitable zone of a red dwarf are tidally locked ("eyeball planets") due to their small distance to the star

So there is very likely to be a huge number of these types of planets with stable conditions over a long period of time.


Flares by the red dwarfs (which are not so rare) could destroy life on these planets

>Flares by the red dwarfs (which are not so rare) could destroy life on these planets

As a layperson, I'm curious how "bad" those flares are. Is it in the realm of possibility that life that develops on these planets could "hide" from these flares when they happen, or evolve defenses against them for when they happen? Or is it more "turn the surface into lava" kinds of events?

~100 times the intensity required to kill even the hardiest microorganisms, bad.


In the places that are exposed to the UV light.

You could have life that's 100m deep underwater, or living in protected structures (caves, etc). Life could evolve more protections against UV (e.g. some kind of carapace that the organism resides within).

Maybe the hard part is figuring out a way to use UV-heavy light to generate energy.

There is also the detectablility aspect. Closer planets mean shorter years which means we can detect them in a short time of observation. It's not that we don't want to find earth like planets, it is that it takes longer, so why not take the easy path even if the planets are questionably habitable.

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