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Red Dwarfs Could Sterilize Alien Worlds of Life
astroengine (1577233) writes "Red dwarf stars — the most common stars in the galaxy — bathe planets in their habitable zones with potentially deadly stellar winds, a finding that could have significant impacts on the prevalence of life beyond Earth, new research shows. About 70 percent of stars are red dwarfs, or M-type stars, which are cooler and smaller than the sun. Any red dwarf planets suitable for liquid water, therefore, would have to orbit much closer to their parent star than Earth circles the sun. That presents a problem for life — at least life as we know it on Earth, says physicist Ofer Cohen, with the Harvard-Smithsonian Center for Astrophysics. Cohen and colleagues used a computer model based on data from the sun's solar wind — a continuous stream of charged particles that permeates and defines the solar system –- to estimate the space environment around red dwarf stars. 'We find that the conditions are very extreme. If you move planets very close to the star, the force of this flow is very, very strong. Essentially it can strip the atmosphere of the planet unless the planet has a strong magnetic field or a thick atmosphere to start with,' Cohen told Discovery News."
I learned about that in Slashdot comments, really. Then reading articles on wikipedia, perhaps about specific stars, confirms that red dwarves are quite flare-y. At best the star may be relatively calm but then it will hurl cataclysmic bursts of crap at you anyway.
There's a species known as Felis Sapiens that evolved from Lister's cat.
Unfortunately they're down to one last surviving member due to a religious war based upon the colour of hats that were to be worn. He has no drive to procreate, as he is so perfect, that he is madly in love with himself. Meeeoowww.
Science advances one funeral at a time- Max Planck
This was quite interesting and comedic for me.. the red dwarfs and the alien world seems interesting to think about!
What have we learned here exactly? It looks to me like we've learned that a particle flux emitted omnidirectionally falls off with the cube of distance - which I think we knew already without a "computer model" - and that magnetic fields protect against solar winds - which we also knew. Yay for science.
See this article, on the subject, from back in 2009.
. Preliminary results from a dedicated research program have shown that planets around red dwarfs could be habitable if they can maintain a magnetic field for a few billion years ...
... ...
The high-energy radiation is predominantly emitted by young stars. As they age, red dwarfs become less magnetically active, while continuing to shine steadily at visible wavelengths for 100 billion years or more.
Therefore, if an orbiting planet can just hold onto its atmosphere through the wild early years of its red dwarf roommate, it could end up being a decent place to live.
Scientists might want to rethink the moniker "habitable zone" if it is filled with a deadly amount of stellar radiation... After all, the very definition of the habitable zone is based on the right amount of energy allow for liquid water reaching the planet...
bickerdyke
HEr pussy was warm and excited and deweoy! it was Otis tujcjiek ethe international swamp rviver of flasrshback on the weawpsa; pf crpoolp? No! Slashdort is wrong! nothing is the wtire of jiowp sotprkwwrru bigfot of the delicious wonab,
This is like your Grandad telling a story coming in and out of legibility. http://www.youtube.com/watch?v...
Wanna buy a shirt?
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This is why the general public has apathy towards such things. Several times a week there's news about another clue as to whether and how to find life beyond earth, which is a good thing, but yet no real answers. I can understand why after a while people start develop an attitude of "call me when you find one [alien]".
Isn't it exactly how Rimmer and the entire crew died? Old news...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Exactly the same thing would happen to Earth if not for its magnetic field. Red dwarfs doesn't seem special in that regard.
If we do find life, it will have evolved in the harshest possible conditions, on a barren irradiated planet beneath a dim red sun. It will be unkillable and probably hungry.
You're not allow to call them red dwarfs now, it's offensive. Vertically challenged native American is the correct term.
Newsflash: Being near a giant nuclear furnace is radiation-y.
Next up: Water is wet, the sky is blue, and Slashdot sucks.
I want to delete my account but Slashdot doesn't allow it.
...about greenhouse gases. We are told that high concentrations will make a Venus out of Mars, that in spite of the young sun being substantially "cooler" than the sun is now, the Earth's high GHG concentration over most of the last 600 million years is responsible for it being substantially warmer than it is now, etc. Surely there are atmospheric chemistries that would keep iron-core, magnetic field equipped, water-bearing planets nice and toasty a good safe distance away from a red dwarf. Give the temperature, life will (probably) find a way...
Of course if it is really the case that temperature is mostly determined by net insolation and perhaps things like the presence of a vast water ocean covering 70% of the surface, with GHGs only contributing an easily saturable "blanket effect" good for a few tens of degrees absolute, well then, I could see that there could be a problem.
Also, it is worth remembering that water is a great radiation barrier. We obviously want to find "land life" because of our occupational bias, but as long as the planet has liquid water oceans, who really cares if the atmosphere is too radioactive for genetic stability? First of all, one can still imagine all sorts of ways that animals or plants could evolve to protect their genetic inheritance and re-stabilize a speciesization process -- a half-dozen sexes, for example, with some sort of majority rule on the chromosome slots, using information redundancy to combat entropy as it were (or evolving more advanced stuff -- genetic "checksum" correction of some sort). Red Dwarfs have much longer lifetimes than the sun, and given ten or twenty billion years, who knows what evolution will kick out? It could be that all of the really old, stable, wise life forms in the Universe evolved around Red Dwarves because mutation rates (and consequently rolls of the evolutionary dice) are high. We don't completely understand genetic optimization as employed in actual evolution, any more than we completely understand how the brain's neural networks avoid some of the no-free-lunch theorems and empirically demonstrated flaws in e.g. classification by even the most sophisticated networks we can yet build. I'm not asserting that there is any "mystery" there, but there are damn sure a lot of scientific questions yet unanswered, and speculating about what we might find living in orbit around a Red Dwarf -- publicly and with much fanfare -- when we cannot reasonably go and find out is science fiction masquerading as science, not the real thing.
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
...wasn't "How can I work in a 'smeghead' joke?", Slashdot might not be the forum for you. I think there's ample openings to post over on TMZ or something.
Being small and dim, red dwarf stars exhibit relatively violent flare activity. For example, flares occur regularly on our own star, but the energy this releases is small compared to what is produced in total. However, a flare like that on a star 10.000 times dimmer than ours can momentarily double the energy output. Moreover, flares on red dwarf stars can emit up to 10.000 times as many X-rays as they do on our sun. Oh, and remember that there can be more than one of these flares at a time. So, any life on planets orbiting stars like these has a lot more to contend with than just atmospheric erosion.
As more red dwarf stars are studied in detail, increasing numbers are being classified as flare stars. This may have to do with the type of core that these class-M stars have. Solar flares are caused by magnetic reconnection events that are responsible for the acceleration of charged particles (mostly electrons) that interact with the solar plasma. Our own sun, a G-type, has a radiative core that may result in a more stable and even magnetic field than is produced by the convective cores of M-type stars. If so, then it may turn out that all red dwarf stars are flare stars and, since class-M stars are by far the most numerous, this will have significant consequences for the Drake equation, i.e. the likelihood of finding other intelligent and communicative civilizations in our galaxy.
It would be extraordinarily depressing if our current mindset on life in our galaxy will mimic our early mindset of life in our solar system 100 years ago. We all thought for sure Mars and Venus would have little green men :(
No it is just that MrLizard is a complete and utter Smeghead!
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
I think with the help of greenhouse gases the planet could be more far away from the star and not be tidally locked, also you have to take in account that the flares will affect the part that is expose to the star so exist the possibility life could survive in the part in the middle of day and night could be protected from radiation
Wouldn't they prefer to be called "vertically challenged Irish Americans"?
This is not the sig you're looking for.
1. Give vasectomies and tubectomies to everyone on alien worlds
2. ?????
3. Profit!
Old red dwarf (2 billion years old )are also more stable and produce less flares so giving life a chance.
...one of the things that is rarely communicated in these sorts of announcements are the error bars in the 'estimate'. Asserting something categorically "is" or "isn't" from what we know is just silly.
We also believe that we've just discovered terrestrial planets 17x the mass of Earth that, according to our calculations, should be Neptunian "small" gas giants.
Like so many sciences, the more we discover, the more we realize how very little we know.
I think it was Carl Sagan who said that - in the context of astronomy & cosmology - we're essentially postulating the entire earth from the equivalent of a cup of seawater. That's probably rather optimistic.
-Styopa
...that such a planet would likely be tidally locked, with one side always facing the star. There would be extreme differences of temperature between the night and day sides, and life might only be sustainable in the never-moving twilight region, depending upon atmosphere convection.
"potentially deadly"
"could have significant impacts"
"a problem for life"
"estimate"
"it can strip"
[...] Cohen told Discovery News
A lot of 'ifs' and some potential for drama, that's Discovery channel for you nowadays. Everything needs to be spiced up and 'made more interesting' by adding suspense, drame, etc.
Even a walk in the park can be potential disaster, not to mention the problems that can occur while taking candy from a baby.
Good thing I have 56 other channels ;)
Stachel
When will the Hollywood or Toho documentary "Godzilla Planet" be made about these amazing discoveries?
Who ever believed that red dwarf suns were candidate solar systems for looking for life? I know that Krypton was supposed to orbit a red sun, but that's total crap fiction. Is this really news?
It's cold outside, there's no kind of atmosphere.... Red Dwarf
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Does it make ne extremely low in the Drake equation?
Donte Alistair Anderson Roberts - hi son!
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This is not new information and I don't know why it's on Slashdot.