The article explains in length what Eyeball Planets are but gives little arguments why life should be more abundant there compared to other planets apart from a vague number argument.
Pro:
- 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.
Con:
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?
https://phys.org/news/2018-04-proxima-centauri-flare-powerfu...
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.
Not necessarily more abundant, just more within reach of our current tools.
It's a bit circular and not really saying anything useful, but at least it's not claiming what the HN title (nor your criticism) is saying
If a planet is closer to its star, it's more likely to be tidally locked. It can however also be in a spin-orbit resonance higher than 1:1.
As to which kind of planet we'll find life on, depends on whether tidally locked planets with habitable zones are more frequent than non-tidally locked planets in a habitable orbit. I don't know that we know the numbers here.
We are learning that there are liquid oceans all over our solar system so I'd argue that the classic concept of a habitable zone is outdated because it doesn't take them into account.
It specifically means "the light from the planets sun is in the range to support surface-level life".
If a distant moon in our solar system has a liquid ocean that A) doesn't mean it's water or anything else sane and B) that habitable zones are poorly defined.
Liquid oceans generated by orbital- or geothermal activity aren't covered in the habitable zone definition and aren't very useful as they usually require a parent body to provide energy to heat the ocean (jupiter for example) but just not enough to boil it off the moon.