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New Paper Explores The Prospects For Life Around M-Class Stars (arxiv.org)

Posted by EditorDavid on from the exploring-strange-new-worlds dept.

Long-time Slashdot reader RockDoctor summarizes the significance of a new paper describing "The Habitability of Planets Orbiting M-Dwarf Stars": Although Star Trek had a minor smattering of "M-class planets" -- a designation that tells one nothing of substance -- "M-class star" is a much more meaningful designation of color, with two size classes, the dwarfs and the red giants... an M-dwarf of 1/10 the mass of the Sun will burn for around 1000 times the time that the Sun does... Therefore, if humanity ever meets an alien species, the odds of them coming from an M-dwarf [system] are already high. If humanity ever meets an alien species that has been around a billion years longer than us and has technology we can't even dream of, then the odds of it coming from an M-dwarf are overwhelmingly high.
This new paper offers "a comprehensive picture of the current knowledge of M-dwarf planet occurrence and habitability," pointing out that most of these stars are apparently orbited by planets packed closely together, with "a paucity of Jupiter-mass planets and the presence of multiple rocky planets." And more importantly, roughly a third of those rocky planets are orbiting in a "habitable zone" -- far enough away from their stars to support liquid water.

69 comments

  1. White Lives Matter by Anonymous Coward · · Score: -1

    Each year, thousands of white people have their lives ended by black crime. At what point do we say that enough is enough? At what point to we recognize the intrinsic value of white lives and that black crime must be stopped? When will we recognize that white lives matter? When will we finally take steps to end black crime and protect white lives?

    1. Re:White Lives Matter by Anonymous Coward · · Score: 0, Troll

      Never. It is essential that we are pitted against each other so that we won't think to go after the 1%.

  2. Ummm, OK... by NoNonAlphaCharsHere · · Score: 0

    I can't help but think that an M-dwarf system would have a much narrower orbital Goldilocks zone, which would *reduce* the odds of having a habitable planet in that orbital belt.

    1. Re:Ummm, OK... by RockDoctor · · Score: 1

      ... which is counteracted by the increased number of M-dwarfs, and their increased lifetime.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    2. Re:Ummm, OK... by Anonymous Coward · · Score: 0

      I'd say that depends on our understanding of goldilocks zones. In theory both Venus and Mars could have had very earth-like atmospheres long ago - but things about the planets themselves didn't allow them to continue to exist like that. If Mars and Venus were swapped in orbits, I'd wonder if Venus would still be earth like now. Although I think Venus would need a better rotation to help with the creation of a magnetic field.

      These things pretty much point to the goldilocks zones of stars being much wider than originally assumed. So even if it's narrower around a red dwarf, it'd still likely be plenty large for life bearing planets.

    3. Re: Ummm, OK... by Anonymous Coward · · Score: -1

      There is no life out there, space nutters. Because we haven't gotten there yet. We are too busy trying to keep a lying cheating thug out of the white house, If this criminal is not deleted, it will be the death of all of us. If you want to keep the space program alive, only TRUMP can do it.

    4. Re:Ummm, OK... by KiloByte · · Score: 5, Insightful

      M-dwarves last for a trillion years while a sun-class star is good only for a few billions (ours is 4.5ba old and in a billion years Earth will be uninhabitable). Which matters exactly zilch when the whole Universe is only 13.8ba old, and you need a few star lifetime iterations to produce enough "metals" (for astronomers anything above hellium is a metal) for life to be viable.

      There's indeed more dwarves than any other kind of stars, but then, their habitable zones are much smaller and they have other problems that are harmful to life in our sense, so they don't have any advantage. Wake me up in a trillion years or two, then life will be strongly biased to dwarf stars.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
    5. Re: Ummm, OK... by Anonymous Coward · · Score: -1

      faggot

    6. Re:Ummm, OK... by RockDoctor · · Score: 4, Interesting

      you need a few star lifetime iterations to produce enough "metals" (for astronomers anything above hellium is a metal) for life to be viable.

      This is probably true. But those stellar generations are not the generations of common stars (dwarf stars, up to, for example, the Sun's mass), but the lifetime of larger, faster evolving stars. You don't get metals further up the periodic table than carbon from a Sun-mass star. The lifetimes of such stars (say, more than 3 Sun masses ; I forget where the exact dividing line is for stars getting up to burning silicon to iron. It's somewhere near that mass.) is much shorter - more like a half billion years, The time for the ejecta from a supernova to become incorporated into the next generation of stars is more significant than the lifetime of the stars.

      Interestingly, there is a fair correlation between the metallicity of a host star and it hosting a "super-Jupiter," but that correlation breaks down for smaller (Neptune-size and Earth-size) planets. While they still form around stars with a solar-similar metallicity on average, they're not more common around higher metallicity. That's odd. There's something going on there that works against the obvious expectation of how things go. I don't know about you, but I'd take that as a sign to pay more attention to observational data than theory.

      they have other problems that are harmful to life in our sense

      The study was (as is normal) carried out with the assumption of the stability zone of liquid water as the criterion for "habitable zone". No other constraint. You might be interested in finding something that would find William Shatner attractive - even if only as food - but that's not the only thing "life" could plausibly mean. A prokaryote-grade of organism with a non-nucleic acid genetic system would be far more interesting than something that beat Shatner at chess with an RNA-world type genetic system.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    7. Re:Ummm, OK... by Gavagai80 · · Score: 1

      You seem to be making a completely baseless assumption that all solar systems are the same size. The planets around an M-dwarf orbit much closer than those around our sun. It's observed fact, not theory.

      --
      This space intentionally left blank
    8. Re:Ummm, OK... by Anonymous Coward · · Score: 0

      Still, in a twist of the statistics, we came to be in a G star... No confirmation bias. No anthropic principle. Explain that.

    9. Re:Ummm, OK... by Anonymous Coward · · Score: 0

      This is probably true. But those stellar generations are not the generations of common stars (dwarf stars, up to, for example, the Sun's mass), but the lifetime of larger, faster evolving stars. You don't get metals further up the periodic table than carbon from a Sun-mass star. The lifetimes of such stars (say, more than 3 Sun masses ; I forget where the exact dividing line is for stars getting up to burning silicon to iron. It's somewhere near that mass.) is much shorter - more like a half billion years, The time for the ejecta from a supernova to become incorporated into the next generation of stars is more significant than the lifetime of the stars.

      Since we are living in the Dark Energy age, big stars are fewer and far between. The Age of Metals may have terminated, There is so much planet-building material in the Universe.

    10. Re:Ummm, OK... by KingBenny · · Score: 1

      Copyright is not only theft. As a form of censorship, it's a crime against humanity.
      i like your style
      by the top comments i can see this must have been pre-election day in the states ?
      i wonder on the statistic however, as we are talking about alien life, how valid b/c ... i cant say it totally compares but for instance the statistics used for crude forex prediction take all data over time to define "pivot points" regardless of the real world circumstance, practically considering the numbers from the post-war period equal to the numbers from the pre-2008 period equal to the numbers of post 2008 equal to the numbers of today
      which imo makes no sense so in this particular case id say if you were looking for similar carbon-based life maybe it holds a little value qua probability but if one would be talking alien life thats totally beyond omega (point, not "goood") as far as my layman-ass can see
      i think, imo and as my not so very humble opinion (at times)
      yay for the racial slur btw, its very constructive but i am all up for free speech to make it more easy to point out the clowns, i dont think that will ever change

      --
      Free speech was meant to be free for all... how can anyone grow up in a nanny state ?
  3. Not putting a spin on things by Anonymous Coward · · Score: 0

    Another problem is that the habitable zone is so close to an M-type star that most of the planets there are probably tidally locked. The sunward side would be hot, while the night side would be frigid, unless there are some possible atmospheric circulation mechanisms that I'm not aware of.

    1. Re:Not putting a spin on things by RockDoctor · · Score: 4, Interesting
      These are matters that the paper discusses. It only takes a couple of hours to read the 44 pages.

      Short version - some close-in planets will be tidally locked, but not necessarily all of them. And (as discussed), the fact that M-dwarfs covers more mass variation than the next three classes of stars combined (F-dwarfs, G-dwarfs like the Sun and K-dwarfs) so it would be safe to expect a considerable variation in the behaviour of planets around M-dwarfs.

      Consider tidal locking in a system with an M-dwarf star, a "hot Jupiter" and our Planet of Interest (PoI). If in orbit around either the hot Jupiter or the star, the PoI might become locked. But with the three in relatively close interaction, the PoI could be disturbed between locking to one, or the other, or alternating, or spinning irregularly. Feel free to use a planet with an irregular - literally chaotic, even - rotation in an SF scenario of your choice.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    2. Re:Not putting a spin on things by PhunkySchtuff · · Score: 1

      Consider tidal locking in a system with an M-dwarf star, a "hot Jupiter" and our Planet of Interest (PoI). If in orbit around either the hot Jupiter or the star, the PoI might become locked. But with the three in relatively close interaction, the PoI could be disturbed between locking to one, or the other, or alternating, or spinning irregularly. Feel free to use a planet with an irregular - literally chaotic, even - rotation in an SF scenario of your choice.

      So that explains the irregular seasons in the Game of Thrones universe... Winter is coming.

      --
      Specialist Mac support for creative pros, Melbourne
    3. Re:Not putting a spin on things by RockDoctor · · Score: 1
      I was actually thinking (very vaguely) of Aldiss' Heliconia (books, and planet). Though I suspect that attaining sufficient environmental stability in a complex system might be challenging for a narratively interesting planet, biologically spending a lot of time in hibernation / aestivation with brief periods of activity when the environment allows, is an effective strategy.

      Never having read a word of it, or seen a second of it, I thought "Game of Throwns" was set on Earth?

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    4. Re:Not putting a spin on things by PhunkySchtuff · · Score: 1

      Game of Thrones seems to be set on an Earth-like world, however with dragons, undead and a degree of magic. They have winters that are sometimes brief and other times plunge the world into a freeze that lasts for generations...

      --
      Specialist Mac support for creative pros, Melbourne
    5. Re:Not putting a spin on things by OolimPhon · · Score: 1

      Try "Cycle of Fire" by Hal Clement.

    6. Re:Not putting a spin on things by Anonymous Coward · · Score: 0

      Consider the possibility of two such planets exchanging orbits the way some moons of Saturn do:

      https://en.wikipedia.org/wiki/Epimetheus_(moon)
      https://en.wikipedia.org/wiki/Co-orbital_configuration

      The short "winters" are caused in the usual manner (tilt of the planet), but "winter is coming" could refer to the exchange of an inner orbit to the outer orbit - a "long winter" lasting a hundred years, and only the equatorial region remaining warm enough for liquid water.

    7. Re:Not putting a spin on things by Zorpheus · · Score: 1

      What's the problem with tidal locking though?
      I once read that the backside would be so cold that the atmosphere condenses there. This is not what happens on Venus though. The dense atmosphere evenly distributes the heat around the whole planet, making the temperature nearly the same everywhere.
      Thinking about Earth I would expect that a constant pattern of air streams could form which transfers the heat between hot to cold areas.

    8. Re:Not putting a spin on things by Mike+Van+Pelt · · Score: 1

      Chaotic rotation... G. David Nordley's "Calendar of Chaos". The scientists had a betting pool on the exact time of the next sunrise. (This wasn't a planet, though, I believe I recall it was Saturn's moon Hyperion.)

    9. Re:Not putting a spin on things by RockDoctor · · Score: 1

      What's the problem with tidal locking though?

      Yes, what indeed is the problem? 'It isn't Kansas any more' as some dog who never went to school once said. If the environment is within the liquid range of water (NB - pressure not counted ; H.sap is moderately labile in this respect, and as long as you don't change presure at more than a factor of 2 per month ... small fucking deal.)

      Oh, it's unfamiliar. Well [hand gestures indicating "big", "mammalian sexual activity", and "redistribution of cards between players".

      [Atmosphere condenses at pole-of-cold] First approximation. Second approximation is that there is heat transfer. Third approximation is that it's a complicated question. And that's before you look at complicated orbits, and complex geology.

      Yes, freezing out on the cold-of-pole isn't impossible. But it's by no means inevitable.

      Thinking about Earth I would expect that a constant pattern of air streams could form which transfers the heat between hot to cold areas.

      Stop dragging reality into a discussion about reality - you'll drag Slashdot (kicking and screaming) into reality.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  4. Re:Ummm, OK... faggot gay boi bitch pussy by Anonymous Coward · · Score: -1
    He vaginified faggot gay boi bitch pussy fat pig. YODA must invade your ASSHOLE.

    How to Shove a Yoda Doll up your ass! The 9 Step Greased Up Yoda Doll Shoving process. Go Linux! Tsarkon Reports

    9 steps to greasing your anus for Yoda Doll Insertion!
    v 4.98.0
    $YodaBSD: src/release/doc/en_US.ISO8859-1/yodanotes/9stepprocess.sgml,v 4.98.0 2016/10/30 13:30:20 tsarkon Exp $

    1. Defecate. Preferably after eating senna, ex lax, prunes, cabbage, pickled eggs, and Vietnamese chili garlic sauce. To better enhance the pleasure of this whole process, defecation should be performed in the Return of the Jedi wastebasket for added pleasure.
    2. Wipe ass with witch hazel, which soothes horrific burns. (Rob "CmdrTaco" Malda certifies that his lips, raw like beaten flank steak from nearly continuous analingus with dogs, are greatly soothed by witch hazel which makes it perfect for the anus after diarrhea.)
    3. Prime anus with anal ease. (Now Cherry Flavored for those butthole lick-o-phillic amongst you - very popular with 99% of the Slashdotting public!)
    4. Slather richly a considerable amount of Vaseline and/or other anal lubricants into your rectum at least until the bend and also take your Yoda Doll , Yoda Shampoo bottle or Yoda soap-on-a-rope and liberally apply the lubricants to the Yoda Doll/Yoda Shampoo/Yoda Soap-on-a-rope. You may need your gay squire/lover to help with this since your fat corpulent ass cannot do a self-reach-around.
    5. Put a n1gger do-rag on Yoda's head so the ears don't stick out like daggers!
    6. Make sure to have a mechanism by which to fish Yoda out of your rectum, the soap on the rope is especially useful because the retrieval mechanism is built in.
    7. Pucker and relax your balloon knot. Doing Kegel exercises several times actuating the sphincter muscle and relaxing it will help prepare your ass for what is to come.
    8. Slowly rest yourself onto your Yoda figurine. Be careful, he's probably bigger than the dicks normally being rammed up your ass!
    9. Gyrate gleefully in your computer chair while your fat sexless geek nerd loser fat shit self enjoys the prostate massage you'll be getting. Think about snoodling with the Sarlaac pit. Read Slashdot. Masturbate to anime. Email one of the Slashdot editors hoping they will honor you with a reply. Join several more dating services - this time, you don't select the (desired - speaks English) and (desired - literate). You figure you might get a chance then. Order some fucking crap from Think Geek. Suck and gag on a Dr. Who sonic screwdriver like it was the Doctor's dick in your mouth. Get Linux to boot on a Black and Decker Toaster Oven. Wish you could afford a new computer. Argue that cheap-ass discount bin hardware works 'just as well' as the quality and premium hardware because you can't afford the real stuff. Make claims about how Linux rules. Compile a kernel on your 486SX. Claim to hate Windows but use it for World of Warcraft. Admire Ghyslain's courage in making that wonderful Star Wars movie. Officially convert to the Jedi religion. Talk about how cool Mega Tokyo is. Try and make sure you do your regular 50 story submissio
  5. Summary is incorrect by 93+Escort+Wagon · · Score: 1

    "Although Star Trek had a minor smattering of "M-class planets" -- a designation that tells one nothing of substance ..."

    Wrong. If you have an M-class planet, you should at least be able to find Roddenberries there.

    --
    #DeleteChrome
    1. Re:Summary is incorrect by Ecuador · · Score: 1

      Yup! The first thing that came to mind upon starting to read the summary, and went for a comment, but, it was the 5th comment posted ;)

      Obviously, the 4 earlier posters should turn in their geek card, Futurama is essential material...

      --
      Violence is the last refuge of the incompetent. Polar Scope Align for iOS
  6. Hows about Make YOUR Life matter by laurencetux · · Score: 0

    setup your home as a "safe zone" (outside lights/cams decently setup landscaping ect) and work in your neighborhood to increase the peace (heck if you want to be snarky setup a little office hut with doughnuts and coffee). Instead of griping work to fix things.

    100K folks will come to a protest but 100 folks won't come to a work day

  7. garbage news by Anonymous Coward · · Score: 0

    heard this 1 year back and they then disclaimed it due to the fact for life it would have to be so close to the star that the radiation would bath most worlds and too far out = too cold.....

    nice try and rehashing crap

  8. ahhhh, the new religion by Anonymous Coward · · Score: -1

    1. There is NO evidence of ANY life beyond Earth. I'm not saying there is none, just that mankind has NO evidence for it. We have evidence that Jesus existed, dinosaurs existed, and the planet Earth is at least 6K years old... so there's actually more evidence for Jesus riding a dinosaur on a 6K year old Earth (all of which are insults aimed at the religious right all the time, even though the Bible never says the Earth is 6K years old or that Jesus rode a dinosaur). For consistency, if one is going to heap scorn on the one set of lunacy, then the other deserves it too.

    2. Since we know NOTHING of "alien life", we have ZERO knowledge of what conditions might lead to such life, sustain it, and/or threaten it. As a direct consequence, we would not know if conditions on a given world were positive or negative for such a life form even if we had an up-close robotic exploration of such worlds. Our first evidence would be the discovery of such alien life, and then we could look at the conditions.

    3. There is little information about conditions on ANY planet around ANY other star. No space probes have been to other stars, or to planets orbiting other stars, and we cannot directly image any of these things with sufficient detail to know much. We only finally got a probe to fly past Pluto this past summer and just LOOK at how much we learned from that one quick flyby with a relatively primitive robot probe - it completely upended our understanding of that planet.

    I grow weary of all these supposedly scientific "papers" claiming to "study" something that is not even known to exist, in places we know next-to-nothing about and cannot even observe with any significant resolution. This paper is as scientific as the old "how many angels can stand on the head of a pin" question, i.e. it's garbage.

    1. Re: ahhhh, the new religion by Anonymous Coward · · Score: 0

      Well, not being able to directly detect something doesn't equate to it not being there. The much larger issue is even if we could directly image something like unexpected lights on the dark side of a planet, and we had some supporting evidence that this may indicate a civilization, we still would have to expend a ridiculous amount of resources just to attempt to send some sort of signal to them, and even more to send a probe. Then we would have to wait for whatever to get there, then wait for a response that may never come.
      Basically, it would be a huge expenditure for very little chance of results.

    2. Re:ahhhh, the new religion by Anonymous Coward · · Score: 0

      You're wrong. Arguably. First, obviously, we need to agree (or disagree, but if you disagree then I've nothing more to say to you) on a definition of life - at least in broad terms. It is generally assumed that "life" means "life as we know it" which means carbon based, using liquid water as its reaction medium. So, given that definition we already can constrain where life will not exist - say the photosphere of a G class star or the core of a Gas Giant. You're also wrong about your "no evidence" non-sense. The fact that we are alive is evidence for life elsewhere. I could be (but ain't gonna be) generous and assume you meant "good, solid, specific evidence". I'll also mention that there's (or was when I studied it decades ago) scholarly consensus that we don't know what "Jesus"'s actual name was, a trivial point. If you'd agree that the Scientific method requires prediction, in order to test/challenge/prove a hypothesis, then claiming that a paper such as the one here, is absolutely "scientific". Your understanding of what is and is not "scientific" seems to be very stunted and ill-informed. So, bottom-line:
      1. No evidence? Wrong. We are evidence, especially taken with the enormous number of exo-planets we've discovered in the last 2 decades. Consider the opposite: that no exo-planets had been discovered despite decades of looking for them. That would clearly be a problem for the "life on Earth is unique" people.
      2. Know nothing? Wrong. We know life (as we know it) requires the existence of liquid water, which in turn requires a planet (or satellite) with certain characteristics and without any (globally) lethal characteristics.
      3.Little information. Well I shouldn't argue that. On the other hand, compared with the information we had 20 years ago, we have a huge amount of information, plus the fact that our understanding of our own Solar System has improved and is continuing to improve. We are better and better able to constrain the planetary conditions necessary for life-as-we-know-it to exist. But of your 3 points, this is by far the most accurate. Our models have failed us pretty dramatically in recent years. I see little reason to trust them. Never-the-less, either you start somewhere and improve by "playing the game" (aka "the scientific method") or you don't ever start - and join some religious cult of "true believers". A lot of mathematicians would be surprised to learn that something has to exist to be studied. That's just not true - most of the structures they study do not have any physical existence. But this seems to be (again) a matter of definition. Our theories have two uses: to explain the past (and present) and to predict the future. In this sense, using theory to attempt to characterize the location of "habitable zones" is perfectly good science - under the presumption that better observational techniques will allow us to begin to test such predictions.

    3. Re:ahhhh, the new religion by Anonymous Coward · · Score: 0

      Man did I screw up that post. No exo-planets would support (not be a problem for) the life is unique to Earth people. And I made some other silly typographical errors. Sorry.

    4. Re: ahhhh, the new religion by Anonymous Coward · · Score: 0

      I never asserted that "not being able to directly detect something [equates] to it not being there"

      What I was pointing out is that for something to be "science" there must be evidence, and while I cited the elements of the oft-slung "Jesus riding a dinosaur on a 6K year old Earth" meme and pointed to there being more "evidence" for THAT, I was pointing out that it was nevertheless a false meme.

      First: "evidence" is NOT evidence that something is POSSIBLE, or even proof that required story elements exist. The evidence for the existence of Jesus and of dinosaurs (and yes, we have plenty of evidence for the existence of both) does not automatically become evidence for Jesus riding a dinosaur.

      Second: "evidence" is not somebody's guess at the probable chances that something exists. A million scientists can imagine the possibilities of life and chances of civilizations in other galaxies, but NONE of that is "evidence"

      All the dreaming and conjecture and educated guesses can be piled up into a mountain of published papers and lectures and web sites and books, but NONE of that is "evidence". It's called "day dreams" and "imagination" and is as scientific as the typical beer-fueled talk in a typical college kids bull session. People who come up with this stuff should be in careers writing science fiction novels, and not wasting everybody's time pretending to be scientists.

      Engineering uses numbers.

      Science uses data.

      Authors of works of fiction use imagination.

    5. Re:ahhhh, the new religion by Anonymous Coward · · Score: 0

      No, I'm not, and I weep for science if your opinions are on the rise

      You say: It is generally assumed that "life" means "life as we know it" which means carbon based, using liquid water as its reaction medium. So, given that definition we already can constrain where life will not exist

      I say: no, I'm more broad-minded and while I'll accept "life as we know it" I'm also willing to accept life that is completely alien to us - in other words I am being MORE generous to the people who imagine life beyond Earth.

      you say: The fact that we are alive is evidence for life elsewhere.

      I say: No, it's only proof that the forms of life we know of exists HERE. There may be plenty of other forms of life, but this is neither evidence for them, nor of their existence elsewhere.

      You say: If you'd agree that the Scientific method requires prediction, in order to test/challenge/prove a hypothesis, then claiming that a paper such as the one here, is absolutely "scientific".

      I say: No, science is much more than prediction, which is just one tiny reason among many for my opposition to horoscopes and fortune cookies which also make predictions. Science does not just require some idiot to predict something. It requires some theory and testability etc and some actual evidence.

      You say: Your understanding of what is and is not "scientific" seems to be very stunted and ill-informed. So, bottom-line:

      I say: Insults by somebody who clearly does not understand even the most basic concept of "evidence" is "stunted and ill-informed"

      You say: No evidence? Wrong. We are evidence, especially taken with the enormous number of exo-planets we've discovered in the last 2 decades. Consider the opposite: that no exo-planets had been discovered despite decades of looking for them. That would clearly be a problem for the "life on Earth is unique" people.

      I say: Nice try. The existence of planet-sized objects orbiting other stars is just evidence of other planets. That's all it is. It's not evidence one way or the other for life, particularly when all the evidence we have from our own solar system is that no planet here other than Earth has any life. There may well be life on Mars or elsewhere in our solar system, but we have no evidence of it yet

      You say: Know nothing? Wrong. We know life (as we know it) requires the existence of liquid water, which in turn requires a planet (or satellite) with certain characteristics and without any (globally) lethal characteristics.

      I say: Wrong. We know that SOME life (what we've seen) requires liquid water. So what. We have not seen liquid water on any exoplanet and we've seen water on mars (albeit frozen) but no life there. We also have seen lifeless water on Earth. Water IMPLIES that life as we know it MAY be possible, but is neither evidence for life, nor is its absence evidence for the absence of forms of life we know nothing about.

      You say: Little information. Well I shouldn't argue that....

      I say: that is wise. We know VERY little of the planets in our own solar system, and a single probe on a slingshot pass by any one of them can generate enough data to completely upend our understanding of an entire WORLD. Just look at all the effort it has taken mankind (over centuries with our actual feet on the ground) to understand life on Earth. We're still learning what we do not know about life here. It's fallacious in the extreme to presume that we know about life on Pluto even though we have just recently flown a probe right past it. That probe provided billions of bytes of information more than what we have for all the exoplanets in the universe COMBINED. Is there life on Pluto? We have no clue. I'm perfectly open to it and I would love to see man set foot on that world and setup a facility and explore that world looking for exotic life forms.... but my hopes that some exotic and fascinating life might be found there or my imagination for what such life might look like is not EVIDENCE.

      The whole exercise of things like the "Drake Equ

  9. Trek's M-class tells you plenty by wonkey_monkey · · Score: 4, Funny

    Although Star Trek had a minor smattering of "M-class planets" -- a designation that tells one nothing of substance

    Then why did you bring it up?

    And actually, in universe it tells you plenty. It tells you humans and most of the other bipedial humanoid life-forms which smatter the galaxy can survive on the surface and breathe the atmosphere. It also tells you it's likely to be littered with polystyrene rocks or to look a lot like parts of California.

    --
    systemd is Roko's Basilisk.
    1. Re:Trek's M-class tells you plenty by Jzanu · · Score: 1

      There is no scientific meaning to it, it is a made up designation with no measurable values to define it. The only value is that it is an entertainment term geeks know.

    2. Re:Trek's M-class tells you plenty by rsmith-mac · · Score: 2

      It also tells you it's likely to [...] look a lot like parts of California.

      And to be fair, California is pretty nice. A good variety of biomes, plenty of arable land, fresh water, etc. "How much like California is it" is, in practice, probably a great definition for the habitability of a planet.

    3. Re:Trek's M-class tells you plenty by RubberDogBone · · Score: 1

      If Star Trek has taught me anything, it is that I like mini skirts a lot, and also nearly every alien world looks a lot like a rock quarry.

      Likewise, Dr. Who agrees: companions seem to prefer mini-skirts and most alien worlds almost always look like rock quarries.

      That's good enough for me.

      --
      Sig for hire.
    4. Re:Trek's M-class tells you plenty by Anonymous Coward · · Score: 0

      Doesn't it mean that there is a Nitrogen/Oxygen atmosphere, and temperatures in the liquid water range?

  10. adsense site l how to Make money From adsense by webprofesionel · · Score: -1, Troll

    https://www.youtube.com/watch?...

  11. Particularly interesting in terms of time by Anonymous Coward · · Score: 0

    It's particularly interesting as M-dwarfs last a LONG time (10 trillion years) so if life exists around them, the expectation time for life is shifted way into the future - see http://phys.org/news/2016-08-e...

  12. Never meet by 110010001000 · · Score: 1

    Humanity could never meet an alien civilization. We cannot travel even a significant fraction of the speed of light. And due to Physics we never will be able to. Sorry, but that is reality.

    1. Re:Never meet by rtb61 · · Score: 1

      So says the mud monkey, https://en.wikipedia.org/wiki/..., 115 years after the first aeroplane. Yep, uh huh, sure, http://mentalfloss.com/article..., mud monkey physics. Sorry but your reality will always be based upon your perception of it, as narrow and primitive as it is. Will we go faster than gravity, yes PS the speed of gravity is the fastest that light can go, so speed of gravity is the measure not speed of light. A child with their hands over their eyes, you can not see them, hence they can not see you, seriously your position is that silly. It makes no difference whether or not they can see us in the tiniest detail or in the tiniest thought, we still have our goals to reach and that includes spreading out into the rest of the galaxy, stop allowing your fear to define what is possible.

      --
      Chaos - everything, everywhere, everywhen
    2. Re:Never meet by RockDoctor · · Score: 4, Informative
      Our species is around 200,000 years old.

      We could spend the next thousand years developing technology, populating the Solar System with our robots, then travel at 0.01c to the nearest 10 planetary systems, and still not have a species which is 1% older than today.

      That's unobtanium-free physics, but I do gloss over the difficulty of crewing and running a generation ship for the thick end of a millennium. It might be easier to develop some form of suspended animation for wombs, and ship frozen embryos for robots to develop, once the robots have built a sufficient space industry at the destination.

      I'm sure that I'm never going to see humanity's First Contact moment. If I wasn't dead when it happens, I'd be astonished if any human which even knew it's 21st century ancestors names were involved. (I don't know the names of any of my ancestors even 5 generations back, let alone 30 or so).

      A species doesn't need to travel at a significant fraction of c in order to colonise the galaxy. Our society probably couldn't do it in any meaningful sense (are we the same society as a thousand years ago - do you speak Old English, or Norman Frankish?), and maybe our species would have speciated into multiple descendant species by the time they get into other spiral arms. But that isn't "never" - just a very long term plan.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    3. Re:Never meet by MichaelSmith · · Score: 1

      Within a few hundred years we should be able to grow animal bodies to specification, as well as scanning and storing human personalities. The first ship to a remote star could be very small. Just an assembler which makes larger assemblers, guided by signals from home. The first humans to make the trip would be essentially teleported to their destination.

      Its a shame that we are missing out on this by such a short time.

      --
      http://michaelsmith.id.au
    4. Re:Never meet by Gavagai80 · · Score: 1

      "Meet" can be interpreted to include any form of communication. For two sufficiently advanced cultures, there's even the theoretical possibility of transmitting the information necessary to construct the alien at the other end.

      --
      This space intentionally left blank
    5. Re:Never meet by Zorpheus · · Score: 1

      Teleporting is a crazy science fiction idea, but the small assembler being sent out is what I also think is the way it will go. In the future we can send small probes that will bring life to new worlds. We can design intelligent lifeforms that are living there, and are a kind of the children of our species. We can send all information that is useful. These new lifeforms will grow out of single cells with the help of small machines built for that.
      But sending whole people to other stars is just extremely difficult and not really worth it.

    6. Re:Never meet by RockDoctor · · Score: 1

      The first ship to a remote star could be very small. Just an assembler which makes larger assemblers

      Frozen wombs (and associated heart-lung machines) with a bucket full of frozen sperm and eggs. The technology is here already.

      It's a "6 vs 2x3" question if we'd improve the technology in the millennium or two while the machine (plus eggs and sperm) was in flights, but fundamentally that's a software issue not the hardware in flight. If the labs on Earth come up with a better way of treating the gametes, upload it (after testing) and in a few generations you might see an answer.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    7. Re:Never meet by RockDoctor · · Score: 1

      Just an assembler which makes larger assemblers, guided by signals from home.

      Only the very highest level of control from "home" (see end note) would be necessary. Near total autonomy would be necessary.

      The first humans to make the trip would be essentially teleported to their destination.

      Hmmm, The amount of data to be transmitted, and the error-checking needed to ensure that a "personality" had actually been sent, is high. A pretty steep obstacle. Why bother? Why not just send some tissue cultures, some nutrients (most being derived as by-products of the mechanised construction of a space industry by the first Von Neumannn achines), and some sperm and eggs of various species, including humans. Then grow the new inhabitants at the far end. Eventually of course you'd lose "control" of the colony, but since that has always happened before after at most a few generations, you knew that was going to happen when you started on the colonisation programme. (If you didn't know, you've just been told.)

      What is your actual purpose behind your colonisation programme? It seems to be different to mine. I just want to see life spread, and possibly our descendants (well, your descendants) will eventually meet other life forms.

      [End note] Since an autonomous space industry would need to be built by the colonisation probe while collecting materials for growing the colonists (and that's probably a 30 year project already), there's nothing to even slow that system from building the infrastructure for building the ext set of colony ships. Even if they didn't do it automatically, within a few generations I'm sure the colonists would do it themselves. So, after the first few colonies are established, then for the average colonisation probe, "home" becomes increasingly unlikely to be "Earth".

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    8. Re:Never meet by david_thornley · · Score: 1

      We currently can't travel at a significant fraction of the speed of light, but look up the 1960s Project Orion. That was a plan for a spaceship to fire off nuclear bombs for propulsion. It was expected to reach a significant fraction of C. Modern physics says we aren't gong faster than light, not that we aren't going to achieve a speed that can manage interstellar travel.

      We can also have generation ships, or possibly automatic ships with crews in some sort of stasis or being frozen. The laws of physics don''t say that either of those ideas is impossible. We're nowhere near ready for the engineering challenges, but that might well change over the next millennium or so.

      There's other possibilities. The Alcubierre drive might well work, if we can find enough stuff with negative mass and find a sufficiently powerful power plant. It's certain that modern physics is wrong about some things, and it's possible that there's something that would make interstellar travel relatively easy.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    9. Re:Never meet by Anonymous Coward · · Score: 0

      Why not just send some tissue cultures, some nutrients (most being derived as by-products of the mechanised construction of a space industry by the first Von Neumannn achines), and some sperm and eggs of various species, including humans.

      Because what would be the point? Spamming the void with life is pointless, you might as well fire your genetic load into the sun for all the good it will do humanity.

  13. Can any Civilization last 1,000,000,000 years? by aberglas · · Score: 1

    Or is there a reset point. When the technology enables them to destroy themselves, at which point it just just a matter of time. Maybe thousands of years, but not billions.

    And the intelligence is unlikely to be biological. How long will it be before humanity is replaced by computers. Not within 100 years, but it is hard to see it not happening within 1,000 years.

    http://www.computersthink.com/

  14. Class - M Planet, not M-Class Planet by Anonymous Coward · · Score: 0

    Fucking idiot doesn't know that Star Trek never used M-Class Planet. Letter class was and is assigned to Stars, with our sun being a "G" Class. Earth is a Class-M planet (Man) for human habital as we don't live on stars and of course, this didn't gauranty that there wasn't something to kill you on the world as all the red shirts discovered in various ways though we never saw anything that was a virus that crossed species boundaries - a few were covered in Enterprise and DS9 but none in ToS.

    1. Re:Class - M Planet, not M-Class Planet by ArchieBunker · · Score: 2

      You're the idiot. M stands for Minshara, a Vulcan word.

      --
      Only the State obtains its revenue by coercion. - Murray Rothbard
    2. Re:Class - M Planet, not M-Class Planet by 93+Escort+Wagon · · Score: 1

      You're the idiot. M stands for Minshara, a Vulcan word.

      I don't believe that came up until Enterprise. But, in any case, in the original series they said "Class M".

      --
      #DeleteChrome
  15. Just because by ve3oat · · Score: 1

    Just because an M-type dwarf will burn for 1000 times longer than our sun doesn't necessarily mean that any civilization in orbit around an M-type star is already older than we are.

    1. Re:Just because by RockDoctor · · Score: 1

      Which is not what I said.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    2. Re: Just because by Anonymous Coward · · Score: 0

      You still said a lot of stupid shit.

  16. M class planet designation by 91degrees · · Score: 1

    I thought that meant survivable to all lifeforms not wearing a red shirt.

  17. Advanced aliens / technologies do not exist by eggstasy · · Score: 1

    It seems to me that it is a safe bet that the known limitations of Physics will never be overcome, to such an extent that we will be able to dominate the galaxy. I.e. FTL travel doesn't seem like it will ever be more than science fiction. Many phenomena are governed by a dipole curve, where things start slowly, then hit a tipping point where they rapidly accelerate until they reach a new level of stability. You see this in economics, in Physics / Chemistry, in the evolution of new species, etc.

    Why are we alone then? If alien civilizations had arisen 1 billion years before ours, and developed technology beyond our dreams, wouldn't they at least leave a trail of some kind?

    Something to consider is that radioactivity decreases with the age of the universe. There is a certain probability that a % of an element will be a radioactive isotope when such elements are created. Less and less heavy elements are being created as the universe ages, and existing ones decay. This means that life will arise more easily.

    http://www.fourmilab.ch/docume...

    1. Re:Advanced aliens / technologies do not exist by Tempest451 · · Score: 1

      "If alien civilizations had arisen 1 billion years before ours, and developed technology beyond our dreams, wouldn't they at least leave a trail of some kind?" An ant crawling on your arm is unaware that you represent a species that has studied quantum physics or explored space. To it, you are a warm obstacle to crawl over. Physicist aren't even certain how large the periodic table could be, It would be the height of hubris to assume that we understand the warm obstacle that we are crawling over.

  18. I suggest that.... by Sqreater · · Score: 1

    ...the development of life of a level that supports advanced intelligence probably needs a certain level of energy intensity across the spectrum in order to develop and that an M-class star doesn't provide that, meaning they would stall at a fairly low level of life and remain there.

    --
    E Proelio Veritas.
    1. Re:I suggest that.... by RockDoctor · · Score: 1

      advanced intelligence probably needs a certain level of energy intensity across the spectrum in order to develop

      Do you have a rationale for making this suggestion. E.G. some biological process unique to "advanced intelligence" and which requires ... well it sounds as if you mean green- or blue- coloured light?

      I know of no biological process unique to "advanced intelligence", for a start. Onegaishimasu - educate me.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  19. A thought just occurred... by Sqreater · · Score: 1

    Does this suggest (however lightly) that perhaps we (humanity) should be looking not to M-class stars but to K-class stars for more intelligent lifeforms and more advanced civilizations?

    --
    E Proelio Veritas.
  20. I meant F-class.. by Sqreater · · Score: 1

    OBAFGKM.

    --
    E Proelio Veritas.
  21. Lack of Jupiters considered harmful by abies · · Score: 1

    I was under impression that Jupiter-size planets are useful in in star systems where you hope to get life. They catch a lot of space debris (up to moon size), preventing some (most?) of it with colliding with rocky, life-bearing planets. Avoiding serious extinction events or even blowing up entire atmosphere looks like healthy thing for fragile, growing life.

    Here we read about 'planetary systems characterized by a paucity of Jupiter-mass planets', but there is no mention of space guard role they fulfill. Is it overrated or we just don't know enough about their importance to put it into scientific paper?

    1. Re:Lack of Jupiters considered harmful by RockDoctor · · Score: 1

      space guard role they fulfill. Is it overrated

      I'm not sure that there is such a role.

      In the history of the Solar system - the only example we have a good understanding of - the orbital interactions of Jupiter and Saturn were (probably) responsible for the "Late Heavy Bombardment" (LHB) of the inner solar system. But the oldest fossils are found from times not long (~ 1/5 to 1/4 of the then-age of the solar system) after that, and there are hints (well, two hints, both moderately controversial and disputed) of life affecting the carbon cycle considerably before then. Clearly the LHB didn't kill off life - we're here. Arguably, the LHB may have been necessary for the development of life (certainly the argument has been made. Not everyone accepts it.)

      But to stay on the point of the "space guard" role of the gas giants. What "guard" role? Yes, Jupiter in particular does throw a lot of objects out into the Oort cloud and Kuiper Belt. The ones in the Kuiper Belt come back as comets at some later date - which may or may not hit anything on the way back. The ones in the Oort cloud also seem to come back - as long period comets, or ones with "hyperbolic" orbits. I can't do the celestial mechanics calculations myself, but I don't think that the gas giants do anything other than delay the dangers from any particular object.

      If you want a "space guard", how about the Sun. By impacting every iceball in the inner Solar system with light, then it gradually erodes their mass and so reduces the potential damage they can do to anything they hit.

      Yes, I have seen claims like this on things like the Discovery Channel (back when I had that channel - I didn't think it worth paying for). I've even seen it coming out of the mouths of perfectly respectable astronomers and planetary scientists. And when you read technical papers from those same scientists ... it's not there. I think it's the sort of sound bite that TV producers like to try to get, and then they use it when they get it, discarding the more cautious statements to the cutting room floor as being not-sexy-enough.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    2. Re:Lack of Jupiters considered harmful by abies · · Score: 1

      Thank you for insighful answer.
      I tried to look for some 'reputable' sources talking about importance of gas giants, but best thing I was able to find so far is something like http://www.dailygalaxy.com/my_..., with "Two NASA astronomers recently suggested[...]" "life-bearing planets may be rare" and other quite vague statements.

    3. Re:Lack of Jupiters considered harmful by RockDoctor · · Score: 1
      Precisely. Spend a few years reading the actual papers that scientists publish for their peers to read and you'll realise that people don't say much about it because it's probably not true. "Our" Solar System has been a pretty violent place in the past, and could be in the future (remember the study that raised a couple of % probability of Venus and Earth swapping places in the order from the Sun and Mercury or Mars being ejected from the system? If that's a possible result of the "protection" of the gas giants ... maybe it's not that much protection.

      Really, we need a less-biased sample of planetary systems (our detection methods are severely biased), and then each one needs a lot of orbital modelling - once we're reasonably sure of the distribution of masses and orbits in each system. Then you need to re-do the modelling with different distributions of plausible initial matter. For each system.

      Currently, we're at the "stamp collecting" stage of the process. We're trying to reduce the biases in the detection methodologies. On case-by-case basis, we're looking at the systems we can measure, but we're still discovering new systems.

      When Kepler finally breaks down irretrievably and there's no new data coming in (apart from a small amount of detail work from JWST and ALMA, but not surveying work), then more work will be done on the existing data set.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"