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Red dwarf stars also flare more frequently than our Sun, unleashing waves of ultraviolet and X-ray radiation that is harmful to life as we know it. If the Sun can strip off Mars’ water and dense atmosphere from a huge distance, planets like Proxima b lying about 30 times closer to furiously flaring stars could lose their atmospheres in just a hundred million years. To make matters worse, such planets being tidally locked means their molten interiors likely churn slowly, generating feeble or no magnetic fields. This deprives the planets from the kind of radiation protection that is so effective here on Earth and contributes to its proliferation of life.
In 2014, NASA’s Swift mission caught a red dwarf emitting a flare 10,000 times more powerful than any ever expelled by our Sun. Most newly born red dwarfs may emit such mega-flares, perhaps in revolt against us having judged them on size. The intense radiation from these mega-flares could prevent life from ever arising on nearby planets.
Well, this makes Red Dwarf a very aptly named vessel and TV program…
It’s cold outside, there’s no kind of atmosphere
Mere-ideas, but…
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there seem to be one hell of alot of the things, so therefore some must have captured rogue-planets, after they calmed-down…
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that would mean that the atmosphere-stripping might not be universal for all planets orbiting them, only for the planets that orbited them when they were young red-dwarfs…
Being tidally-locked may mean that not having any Van Allen belts may be irrelevant: the radiation they’re being bombarded by is coming from their sun, & life could evolve on the opposite side, having warmth, & maybe photosynthesis at the daylight-horizon?
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Swift caught a red-dwarf emitting a flare 10k times more powreful than any we know about having been ejected by our Sun … but we’re looking at zillions of stars with our satellites, whereas we’ve only got a few decades of satellites watching our sun: there’s a measurement-disparity there, that is significant.
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universe has surprised ALL of our assumptions about it, through the millenia… & the ONE rule on Earth for where life is, is: IF life CAN exist in some niche, THEN it does. Period.
Stratospheric bacteria with error-correcting-code DNA ( 4 compartments, each with about 1/3rd of the DNA, so it corrects radiation-induced-damage before dividing into daughter-cells, sorry I can’t remember where I read that, it was a couple decades ago ), bacteria eating bedrock, down where it’s too hot for anything else to live, etc…
To presume, as we normally do, that universe’s rules for life are different on Earth than everywhere-else, is … neither evidence-based nor correct-reasoning-based.
Therefore, betting that no red-dwarf-orbiting planet has any life on it … isn’t a bet I’d do.
That most such might be lifeless, I’ve no problem with that.
But any time we assert that “there’s no life” in an entire-category of universe’s places … that’s just prejudice, from what I can see.
There is some, indirect evidence that microbes used to live on Mars ( chemistry that has no other obvious explanation, e.g. )…
& that would indicate that life’s actually a normal-default, but that we evolved too-late to encounter Mars’s life…
Oh, & the flaring thing: being closer to a star makes flaring much more dangerous than it is to us: the energy-density at double the distance ( of the flare, between its sun & its planet ) would be 1/4, right? ( distance-squared ),
so closer would be massively more likely to be clobbered…
but … universe consistently surprises our assumptions, so I’m still holding-to the suspend-judgement, only speak for the majority, not for all, position.
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*a lot.
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A large planet in the habitable zone of a red dwarf can be docked and always show the same face to the sun. Due to the frequent solar flares of a red dwarf, this part of the planet is devastated, but not necessarily the dark side. Apart from this, a red dwarf is quite violent in its first part of life, but not so much after a certain age, which in this type of suns is billon years more than in suns like ours or larger. Basic life can exist almost everywhere as shown. This is why it can never be ruled out that life exists on this planet, if there are indications of life even on Venus in high layers of its atmosphere.
Another thing is if we talk about advanced or even technological life, this already requires much more limited margins of conditions. For example, advanced technology requires fire domination as a basis, therefore it excludes oxygen-free environments and aquatic worlds, but even there can exist intelligent life (even on Earth sometimes).
So a sort of laser from space?
The one thing that might save the situation is that a planet in a red dwarf’s habitable zone would become tidally locked within a few hundred million years after formation, but stripping away the atmosphere could take up to around 2 billion years. This gap might be long enough for intelligent life forms to evolve in the temperate zone created by the tidal locking.
It’s cold outside. There’s no kind of atmosphere. I’m all alone. (More or less)
