Bad news for alien life? Even calm red dwarf stars rage more violently than the sun

[Admin]

Even quiet red dwarfs are prone to extreme outbursts that put our sun to shame, with significant implications on the search for alien life.

Bad news for alien life? Even calm red dwarf stars rage more violently than the sun : Read more

 

[rod]

"We find that most stars are significantly variable, even the quietest stars," the authors explained, adding that 75% of the 57 stars in the sample displayed long-term variability. "We find long-term timescales ranging from several years to more than 20 years." The team acknowledged that this examination of red dwarfs and their variability is really just a first step in understanding these violent stars. They also stated that the true behavior of red dwarfs may be even more complex than these results suggest."

Red dwarf star hosts seem important in astrobiology studies. The exoplanet.eu site shows 917 exoplanets around stars from 0 to 0.7 solar masses, includes TRAPPIST-1 system. Red dwarf stars more variable and hostile to life, reduces the number of potential exoplanet candidates for life on them. So far, no exoplanet is confirmed with life either tiny or E.T. phoning home

 

[Mergatroid]

OK, I don't know who's making things up, but the stars of Red Dwarf have never to my knowledge "raged" on anything.
Graig, Danny, Chris, Robert and both Norman and Hattie have always been great people.

Red Dwarf (TV Series 1988– ) ⭐ 8.4 | Comedy, Sci-Fi

30m | 12

www.imdb.com

Seriously though, all the science articles I have read specifically point out how the radiation and flairs from a red dwarf are much worse than for SOL sized stars and are poor candidates for the search for life. Planets around them also tend to be tidally locked.

 

[Helio]

This further supports earlier claims that red dwarfs are a bit too fisty to favor atmospheres, and life. There is still that one report indicating that the flares may not be that often spewing along their ecliptic, thus exoplanets might avoid a lot of the problems. But this study was very limited and likely just a statistical fluke.

Fortunately, most of the exoplanet discoveries are in the G-class of stars, which our Sun is a G2V. Here are some stats showing how the G-class stars, which are easier to see since they are much brighter, have more exoplanets.

 

[JAS]

Even quiet red dwarfs are prone to extreme outbursts that put our sun to shame, with significant implications on the search for alien life.

Bad news for alien life? Even calm red dwarf stars rage more violently than the sun : Read more

These outbursts, as well as eruptions of scorching-hot plasma known as coronal mass ejections (CMES), can be incredibly destructive to planets orbiting red dwarfs, stripping their atmospheres and emitting enough radiation to boil away liquid water

While these flares may be strong enough to boil away liquid surface water, what about a mile-thick ice sheet? If it turns out that statistically speaking, the Universe favours ocean life below a nice thick ice-sheet, would the red dwarfs and their long lives favour the long-term evolution of life, while the ice-shield protects that developing life from those pesky flairs? So far, I haven't seen any science to support or refute such a statement.

 

[jamestmallow]

This further supports earlier claims that red dwarfs are a bit too fisty to favor atmospheres, and life. There is still that one report indicating that the flares may not be that often spewing along their ecliptic, thus exoplanets might avoid a lot of the problems. But this study was very limited and likely just a statistical fluke.

Fortunately, most of the exoplanet discoveries are in the G-class of stars, which our Sun is a G2V. Here are some stats showing how the G-class stars, which are easier to see since they are much brighter, have more exoplanets.

Is there any bias in that data such as it being easier to spot planets around certain star types due to brightness ?

 

[Dave]

The truth is we know very little about red dwarfs. Intelligent life on these worlds would evolve in a much different way. We continue to look at these worlds from an earth-centric point of view. There are many variables that exist where intelligent life may thrive on these worlds. A world with a single large moon orbiting a yellow star in its habitable zone, is one way for intelligent life to thrive, in our galaxy. Let us not be hasty discounting other ways. There are as many variables out there that equal the vast number of stars. Can a world's magnetosphere be stronger than our own world? A very real scenario. This is only one example. As we have seen on earth; life will find a way.

 

[jamestmallow]

The truth is we know very little about red dwarfs. Intelligent life on these worlds would evolve in a much different way. We continue to look at these worlds from an earth-centric point of view. There are many variables that exist where intelligent life may thrive on these worlds. A world with a single large moon orbiting a yellow star in its habitable zone, is one way for intelligent life to thrive, in our galaxy. Let us not be hasty discounting other ways. There are as many variables out there that equal the vast number of stars. Can a world's magnetosphere be stronger than our own world? A very real scenario. This is only one example. As we have seen on earth; life will find a way.

Maybe, or maybe the rare Earth hypothesis is correct and we are the only complex life forms currently inhabiting the Milky Way.

 

[Unclear Engineer]

Maybe, or maybe the rare Earth hypothesis is correct and we are the only complex life forms currently inhabiting the Milky Way.

Even if it takes a "rare Earth" for life to initiate and evolve, it still seems improbable that our Earth is the only planet in the entire gallaxy to have/had/will ever have any life on it.

But, that still doesn't make it probable that we will ever find any of it even, if it is "out there".

 

[jamestmallow]

Even if it takes a "rare Earth" for life to initiate and evolve, it still seems improbable that our Earth is the only planet in the entire gallaxy to have/had/will ever have any life on it.

But, that still doesn't make it probable that we will ever find any of it even, if it is "out there".

I have no doubt that microbial life exists elsewhere, probably on some of the ocean worlds in the solar system, but complex, multicellular life seems less likely. A technological civilization seems highly unlikely. Perhaps in some far off time and / or galaxy, but nothing we are likely to detect.

 

[Unclear Engineer]

I have no doubt that microbial life exists elsewhere, probably on some of the ocean worlds in the solar system, but complex, multicellular life seems less likely. A technological civilization seems highly unlikely. Perhaps in some far off time and / or galaxy, but nothing we are likely to detect.

With estimates of something like 100 to 400 billion stars in our galaxy, it seems odd that you would think that the empirical evidence of 1 civilization (us) is somehow compatible with an estimate of no others. That is like saying the odds are 0.25 - 1.0 x 10^-11, but not 0.5 - 2.0 x 10^-11.

Our Earth has not had a nice, even, multi-billion year history that nurtured life from a beginning to now without challenges. In fact, it may well be the challenges that led to the development of highly adaptabe life forms that adapted with "technology" and "civilization".

So, if you are willing to believe that simple life occurs with some substantial frequency, it seems logical to think that it may very well result is what we would call intelligence in a variety of situations.

That does not mean space-faring creatures that can roam the galaxy at will. We really do not have evidence that those are even possible.

And, if we don't get better control of our own behavior, it seems that our data point could become an example of a relatively short time period for a technologically capable civilization.

But, we really have no information about whether even our relatively close neigboring stars ever had in the past, or ever will have in the future, technological beings inhabiting them.

 

[jamestmallow]

With estimates of something like 100 to 400 billion stars in our galaxy, it seems odd that you would think that the empirical evidence of 1 civilization (us) is somehow compatible with an estimate of no others. That is like saying the odds are 0.25 - 1.0 x 10^-11, but not 0.5 - 2.0 x 10^-11.

Our Earth has not had a nice, even, multi-billion year history that nurtured life from a beginning to now without challenges. In fact, it may well be the challenges that led to the development of highly adaptabe life forms that adapted with "technology" and "civilization".

So, if you are willing to believe that simple life occurs with some substantial frequency, it seems logical to think that it may very well result is what we would call intelligence in a variety of situations.

That does not mean space-faring creatures that can roam the galaxy at will. We really do not have evidence that those are even possible.

And, if we don't get better control of our own behavior, it seems that our data point could become an example of a relatively short time period for a technologically capable civilization.

But, we really have no information about whether even our relatively close neigboring stars ever had in the past, or ever will have in the future, technological beings inhabiting them.

With our gem of a planet it took 4 billion yrs for complex multicellular life to appear and another 1/2 billion for a techno civilization that, as you pointed out, may not last long. Sure, either or both may exist at some point in time in the galaxy but it seems unlikely 1 would detect another. The odds that they exist at the same time anywhere near each other seems highly remote. Of course we have very little data to work with at the moment, so we speculate.

 

[Dave]

A more advanced form of intelligent life is observing us. The reason to speculate this scenario is because we will very likely do the same in our own future, as well. This is the future of humanity. A more advanced species will not contact a warlike socially aggressive species, such as the way we are now.
Will they contact us when we learn to become one as a species? Perhaps. Imagine 300 million seeds being cast and only one takes root, not a likely scenario in a galaxy that is a habitat for life and intelligent life. A more intelligent lifeform will not give us that 'smoking gun.' They have the technology to easily accomplish being hidden. We live in a reality in which science offers little to no help.
Do not cast aside speculation so easily, in this scenario, it is your superpower.

 

[Helio]

Is there any bias in that data such as it being easier to spot planets around certain star types due to brightness ?

Very much so, though astronomers are well-aware of this and most other biases.

Since red dwarfs are the must numerous stars, it's a bit ironic that they don't have the most observed planet number, but they are the hardest stars to observe since they are so dim. They are also the easiest to detect using the radial velocity method since lighter mass stars produce more redshifts/blueshifts. [20% of all exoplanets found with this method. 70% found using the transit method.]

Since a red dwarf is small, then astronomers can detect the smaller planets with the transit method. Small planets with a large star behind it can make too little difference to detect them out of the noise from their photometry. But small transiting planets that block light from a small star background produce clearer results.

On the other hand, as photometry improves (space scopes), then the larger stars will have better advantage since less perfect transit alignment (orbital inclination) favors the larger stars.