[HN Gopher] NASA study finds life-sparking energy source and mol...
       ___________________________________________________________________
        
       NASA study finds life-sparking energy source and molecule at
       Enceladus
        
       Author : wglb
       Score  : 378 points
       Date   : 2023-12-16 05:07 UTC (1 days ago)
        
 (HTM) web link (phys.org)
 (TXT) w3m dump (phys.org)
        
       | ianai wrote:
       | yesterday: https://news.ycombinator.com/item?id=38652897
       | 
       | Hydrogen cyanide, acetylene, propylene, ethane, propene. There's
       | bacteria that live off acetylene (though surely abiotic processes
       | too). I suspect this indicates plenty of energy and complex
       | chemistry on Enceladus. Some of those compounds are energetic
       | while others (I think?) are combustion bi-products. Otherwise, I
       | wonder when/if we'll ever see oxygen (O2) confirmed in a study
       | like this? I realize it's highly/easily bound up in reactions,
       | but what a finding that'd be. They list a probability of 0.64
       | (aka 64%) chance of O2 here. Imagining a surface of water ice and
       | near vacuum atmosphere, I suspect any free oxygen would be very
       | difficult to detect. But they also see co2 so maybe any oxygen is
       | quickly used up? source:
       | https://www.nature.com/articles/s41550-023-02160-0.epdf
        
         | passwordoops wrote:
         | Hydrogen cyanide, acetylene, propylene, ethane, propene would
         | all react very quickly with oxygen, if it is being produced.
         | 
         | I imagine like early earth, if there are organisms they are
         | following an anoxic pathway
        
           | ianai wrote:
           | So is it because the life signals so far suggest simple life
           | that money isn't really pouring into an expedition? That's my
           | inkling anyway. Turns out us apes are still far more
           | interested in everyday stuff than even life outside our
           | sphere.
           | 
           | i.e. I would expect "enthusiasm" to look like discussions on
           | building the infrastructure for multiple missions out there.
           | Communications way points, some basic resource stuff, etc.
           | Stuff to make getting things in that system more robust and
           | timely.
           | 
           | Edit: Maybe experiment/do the laser propulsion tech.
           | "Lighthouses" at critical points.
        
             | staplers wrote:
             | The discovery of even the most base simple lifeform outside
             | Earth would be forever world-changing.
             | 
             | Society, religion, mass institutions would be forced to
             | reconcile with this fact.
             | 
             | I don't think it's necessarily about money.
        
               | NateEag wrote:
               | What do you think would change about religions?
               | 
               | The only one I know well is evangelical Christianity,
               | having been raised in it.
               | 
               | I've read through the Protestant Bible several times, and
               | I'm not aware of anything in it that changes meaningfully
               | if there's other life forms in the universe.
        
               | martin-t wrote:
               | You overestimate people. Most wouldn't care at all, a few
               | would say that's cool and move on. Religious people would
               | just say their favorite god created those too. Unless the
               | aliens were more advanced than us, nothing would change.
        
               | cwillu wrote:
               | The struggle with the religious types is forever that
               | they can't be pinned down in the details: it's not that
               | new information can't be assimilated because it conflicts
               | with doctrine, it's that doctrine, aside from a few very
               | core concepts, is extremely fluid and will seamlessly
               | flow and change to admit the conflicting information
               | without affecting anything of importance.
        
         | Symmetry wrote:
         | I'd be very surprised if we saw oxygen. Photosynthesis took
         | much longer to evolve on Earth than life did in the first
         | place, and on Enceladus you have both a thick layer of ice
         | preventing sunlight from reaching liquid water and also a much
         | dimmer Sun in the first place due to how far away Jupiter is.
        
           | Sharlin wrote:
           | *Saturn, but yes. If there's life, free oxygen would likely
           | be incredibly toxic to it, just like it was to early life on
           | Earth (and still is to some chemosynthesis-based ocean floor
           | life).
        
       | intrasight wrote:
       | I don't much like the spark and fire analogy with life. Not sure
       | what analogy works. We don't yet really understand life well
       | enough to have a good one.
        
         | TeMPOraL wrote:
         | What oxygen-breathing cells do is pretty much nanoscale
         | combustion, so the analogy seems apt.
        
           | mensetmanusman wrote:
           | The proton gradients are quite different from combustion
           | though...
        
             | anticensor wrote:
             | The proton gradient serves to regulate the combustion, one
             | molecule at a time...
        
       | superposeur wrote:
       | This is intriguing and I'm very happy this exploration is being
       | done.
       | 
       | But, for decades, I've been reading reports of the discovery of
       | evidence for the _trappings_ of life elsewhere: water and
       | organics and "habitable" exoplanets. These are valuable
       | discoveries, but the tone of the reports suggest they imply life
       | is about to turn up.
       | 
       | It's worth remembering that there is not one single shred of
       | evidence that life has ever existed anywhere in the observable
       | universe but Earth. Moreover, no one has succeeded in hatching
       | living matter from non living matter and we must honestly say we
       | do not know how this process came about or the faintest estimate
       | of how likely it is to occur (despite much speculation, some of
       | which may turn out to be correct but equally may turn out to be
       | dead wrong). The oft cited fact that life arose "quickly" after
       | the formation of Earth has no bearing on the question.
        
         | tshaddox wrote:
         | > It's worth remembering that there is not one single shred of
         | evidence that life has ever existed anywhere in the observable
         | universe but Earth.
         | 
         | I'm curious how your epistemology is working here. It seems to
         | me that this will also be true in the future if we have found
         | life on a hundred other planets. There still won't be a shred
         | of evidence of life _anywhere else_ , and we still won't have
         | the faintest estimate of how likely it is to occur, right?
        
           | ianai wrote:
           | idk, I think if we see even simple life at multiple points in
           | our own system that we can increase our expectations for the
           | prevalence of life very significantly.
           | 
           | And of course given how vast and indifferent to life the
           | universe is, life would still be vanishingly rare in the
           | universe. It's going to be always precious and a gem.
        
             | superposeur wrote:
             | I agree, _if_ -- that's an enormous "if".
        
               | ianai wrote:
               | But it's actually possible to explore our solar system!
               | We've been at it since the 70s!
        
               | superposeur wrote:
               | Yes and I'm glad we're doing it! No life or fossilized
               | remains of life of any kind has yet been found.
        
               | peyton wrote:
               | Have we sent up any archeological tools for sample prep
               | and whatnot? Can't find what we don't look for, no?
        
               | itishappy wrote:
               | Yup! We've sampled the Moon a number of times, and we're
               | currently trying to figure out how to get one back from
               | Mars...
               | 
               | https://mars.nasa.gov/msr/
        
             | edgyquant wrote:
             | Why? That could just mean our solar gave rise to life and
             | not earth alone. Still don't see why that increases the
             | odds outside of our solar system
        
               | itishappy wrote:
               | If it can spread between planets, it could conceivably
               | spread between stars.
        
           | superposeur wrote:
           | If, in a volume of space, there are N exoplanets and 100
           | spontaneously created life, then I'd crudely estimate the
           | probability of life at 100/N for a given exoplanet.
           | 
           | Currently, we have only an _upper limit_ on the probability
           | and barely even that. All observations are consistent with a
           | probability less that 10^-40, meaning it certainly wouldn't
           | happen a second time in the observable universe.
        
             | spenczar5 wrote:
             | How many exoplanets would you say we have _proven_ have no
             | life? You imply 10^40 exoplanets are known to harbor no
             | life. That is probably vastly more than the number of
             | planets in the observable universe (something in the wide
             | region of 10^20 to 10^25).
             | 
             | Something like 5,000 exoplanets have even been discovered.
             | We can't cross off many of those as _certainly_ lacking
             | life.
        
               | superposeur wrote:
               | I'm certainly not claiming the actual probability is
               | 10^-40 , only using this as an example consistent with an
               | upper limit, which probability would imply life has not
               | arisen a second time in the observable universe. Actually
               | this is way overkill -- as you say, even if the
               | probability is as high as 10^-25, life on Earth is still
               | probably the only instance in observable universe. The
               | point is that we have _no idea_ what this all important
               | parameter is.
        
               | spenczar5 wrote:
               | Our upper limit is something like 10^-1. After all, there
               | is life on earth! Our lower limit is 10^-25 or so.
               | 
               | Why pick the lower limit? Existence of life on earth is
               | extremely powerful evidence.
        
               | superposeur wrote:
               | Ah, but in my opinion we can't call 10^-25 a lower limit
               | since, if life didn't occur in this collection of
               | planets, we wouldn't be here asking the question in the
               | first place!
        
             | jahewson wrote:
             | You've not accounted for the tiny number of observations
             | that we've made nor the limited power of our observations.
             | We're not even sure if life existed on the planet literally
             | next to us, let alone these exoplanets. Otherwise I could
             | argue that all observations are consistent with a
             | probability less than 10^-10 or 10^-20 or any other number
             | I feel like.
             | 
             | Ask yourself this, from how many planets in the universe
             | would you be able to observe life on Earth?
        
           | s1artibartfast wrote:
           | the epistemology rests on how you construct the question, and
           | the underlying logic.
           | 
           | "Does life exist anywhere besides earth" is a very different
           | question than "does life exist outside these 100 planets".
           | Because they are different questions, the relevancy of data
           | and hypotheses are different.
        
           | notjoemama wrote:
           | Using this same logic (in an ad absurdum context) we could
           | also say you will never die because no one anywhere has any
           | evidence that you have. That doesn't falsify your statement,
           | but using ad absurdum shows a statement is not true in every
           | context. I tend to think that shows less conclusion and more
           | investigation may be warranted. That's how I think of it, but
           | I could be off base and I'm open to being mostly if not
           | entirely wrong.
        
             | tshaddox wrote:
             | We have pretty good explanations for why people die and why
             | we expect everyone alive today to die unless we acquire new
             | knowledge that enables us to prevent it.
        
           | mvdtnz wrote:
           | The God of the gaps.
        
         | FL33TW00D wrote:
         | The lack of interest in abiogenesis in most circles is truly
         | outstanding.
        
           | ianai wrote:
           | And here's another thing. With how difficult it is to probe
           | new physics, we stand to do a lot more research by simply
           | inspecting all the observable universe than trying to build
           | colliders.
        
             | dylan604 wrote:
             | Finding a new particle doesn't necessarily threaten
             | strictly up held religious beliefs like finding life
             | somewhere other than this rock
        
               | local_crmdgeon wrote:
               | Catholics officially believe in aliens, and that we
               | should save them (if they weren't visited by Jesus)
               | 
               | Jews wouldn't care either. Don't know about Muslims, but
               | it's not threatening to the other Abrahamic religions
        
               | dragonwriter wrote:
               | > Catholics officially believe in aliens,
               | 
               | A definitive position on the existence of aliens is not
               | part of the Catholic faith.
               | 
               | But, the church admits the possibility and church
               | institutions have done some explorations about what the
               | implications of such contact might be, and how Catholic
               | doctrine might apply to different possibilities.
        
               | local_crmdgeon wrote:
               | Apparently you are correct!
               | 
               | https://www.catholic.com/qa/whats-the-catholic-position-
               | on-t...
        
               | CamperBob2 wrote:
               | _Catholics officially believe in aliens, and that we
               | should save them (if they weren't visited by Jesus)_
               | 
               | Reminds me of the punch line to an amusing first-contact
               | cartoon, one that makes the (unstated) previous line easy
               | enough to guess: "Yeah, he comes by every couple of
               | years. We gave him a nice box of chocolates when he first
               | visited. What'd you guys do?"
        
               | edgyquant wrote:
               | Muslims recite that Allah is "lord of all the worlds"
               | every day. Think they'll be fine. This is true of every
               | religion I think, it's only the non religious projecting
               | that state it would "upend widely held beliefs"
        
             | itishappy wrote:
             | Inspecting the universe can be a lot harder than building
             | colliders. Observing some of the short-lived high-energy
             | particles would require shipping detectors to a high-energy
             | location like the sun, then pulling a signal from all that
             | noise.
        
           | sz4kerto wrote:
           | There's quite a bit of interest; e.g. ex-colleagues of mine
           | have spent lots of effort on refining the 'chemoton' model. I
           | think it's a fascinating subject.
           | 
           | "The basic assumption of the model is that life should
           | fundamentally and essentially have three properties:
           | metabolism, self-replication, and a bilipid membrane.[3] The
           | metabolic and replication functions together form an
           | autocatalytic subsystem necessary for the basic functions of
           | life, and a membrane encloses this subsystem to separate it
           | from the surrounding environment. Therefore, any system
           | having such properties may be regarded as alive, and it will
           | be subjected to natural selection and contain a self-
           | sustaining cellular information."
           | 
           | https://en.wikipedia.org/wiki/Chemoton
           | 
           | https://www.nationalgeographic.com/premium/article/he-may-
           | ha...
        
             | borissk wrote:
             | Bilipid membrane is not necessary for life - life may have
             | evolved inside naturally occurring bacteria sized pores
             | inside inorganic material.
        
           | scythe wrote:
           | It's like saying that mathematicians are uninterested in the
           | Collatz conjecture. Scientists usually work on problems where
           | they have a reasonable expectation of making progress.
           | Attempts to replicate abiogenesis so far have been largely
           | haphazard, with ill-defined criteria of what progress means.
        
         | idlewords wrote:
         | I would turn your logic around and say, everywhere we are able
         | to look, we find evidence that life is more likely than
         | expected. Until the 1990's it was an open question whether any
         | other star had planets; as soon as we got the tools to test
         | that, we found they were ubiquitous. As soon as we got the
         | right instruments to Mars, we found signs of moving water,
         | methane sources, and complex organic molecules in what is
         | basically an Earth-like old lake bed. The moment PCR technology
         | made it possible to do the search, we found a massive 'dark
         | biome' extending many kilometers into the Earth's crust.
         | 
         | When you immediately find strong pieces of circumstantial
         | evidence the moment you acquire the tools to start looking for
         | something, the correct conclusion to draw is not "we have yet
         | to find a shred of evidence", but that further searching is
         | likely to be highly worthwhile.
        
           | superposeur wrote:
           | These factors are what I call the "trappings of life". It is
           | a completely open question (and I mean _completely_ ) how
           | likely life is to arise spontaneously when these factors are
           | present. One single instance of life elsewhere or successful
           | abiogenesis in the lab would change that, but we have
           | neither.
        
             | malfist wrote:
             | We've barely started looking. It's like picking up one
             | piece of hay, not finding a needle and declaring there's no
             | needle in the haystack.
        
               | superposeur wrote:
               | No is declaring that there is no needle in the haystack.
               | Please actually read my post.
        
               | stouset wrote:
               | "I just want to be clear that we've definitely not
               | actually found life. We've found likely precursors
               | everywhere, habitable bodies everywhere, have plausible
               | theories on how to go from precursors to bootstrapping,
               | and see life in every corner of the planet we have
               | explored. But just to be clear we haven't actually found
               | life anywhere else yet."
               | 
               | Yeah, we know. So what then was the _point_ of your post?
        
               | superposeur wrote:
               | Well, perhaps you know that none of the recent findings
               | are evidence of life, but in my conversations with others
               | I have perceived a great deal of confusion on this point,
               | even among scientifically literate colleagues. Also, the
               | fact that we have zero understanding of the probability
               | of abiogenesis is, in my experience, a greatly under-
               | appreciated fact. I speculate that the way findings are
               | reported contributes to this confusion.
               | 
               | Also, at risk of incurring a flame, I'll gently point out
               | that you are folding into this confusion and reinforcing
               | it with your language: "likely precursors everywhere,
               | habitable bodies" ... we absolutely do not know that
               | these conditions are "likely" precursors, which is a
               | statement about a probability we know nothing about and
               | as for "habitable" we do not actually know anything about
               | whether or not a body is habitable in the sense of likely
               | to spontaneously form life.
        
               | yieldcrv wrote:
               | absence of evidence is not evidence of absence
               | 
               | sorry your life has created this crusade of rhetorically
               | reminding people about the absence is evidence
        
               | superposeur wrote:
               | Not in general, just on this particular point. Because,
               | in my opinion, we as a scientific community are currently
               | flush with the (very cool) unexpected discovery of so
               | many exoplanets and it is somewhat distorting our
               | collective thinking about life and its origins.
        
               | creer wrote:
               | We SHOULD (be flush and distorted). We can be realistic
               | AND enthusiastic about it. Some technically challenging
               | work was done and achieved results FAR FAR beyond
               | expectations. That is a result worthy of changing
               | outlook. Before, the outlook was on statistical grounds
               | (the universe is so vast that there has to be). Now this
               | outlook has been justified a billion billion times over.
               | It's certainly time to be far more ambitious and inverse
               | the presumptions that we had before.
               | 
               | I.e. before, "there had to be - some, somewhere" and now,
               | "there is most likely all over the place".
        
               | idlewords wrote:
               | You can make the less charged argument that expanding the
               | search for life has in every case so far led to extremely
               | interesting scientific discoveries. So as a pragmatic
               | strategy, it has legs regardless of where you stand on
               | the question of life origins.
        
               | hesk wrote:
               | Provided you're actively and systematically looking for
               | evidence, then absence of evidence is evidence of
               | absence.
        
               | malfist wrote:
               | But we've not even started doing that yet. None of the
               | mars rovers have landed anywhere close to where we think
               | is must likely to currently harbor life due to fear of
               | contamination.
               | 
               | We've just now learned how to analyze atmospheres of
               | exoplants.
               | 
               | 5 years ago, we couldn't see exoplanets smaller than
               | jupiter.
               | 
               | A decade ago, we couldn't see exoplanets at all.
        
               | Shekelphile wrote:
               | We still can't see the atmosphere of the majority of
               | exoplanets. Can't get around it unless we build a
               | telescope thousands of times bigger than anything else or
               | we make some incomprehensible breakthrough in optics. If
               | we could we would detect life on another planet within a
               | matter of a few hours of telescope time most likely.
               | 
               | I find the entire idea that life could only exist on
               | earth farcical. A lot of people in this thread don't seem
               | to understand that we can't directly image many
               | exoplanets to begin with and that we haven't even been
               | trying to find life on other planets and moons in our own
               | solar system, it has in fact been suppressed every time
               | credible circumstantial evidence of life is found (Viking
               | lander experiments and methane on mars both come to mind)
        
             | vlovich123 wrote:
             | I agree it's an open question, but I think it's highly
             | likely with lots of circumstantial evidence that life is an
             | evolutionary emergent phenomenon where inorganic material
             | reactions create life. We already know that's the case in
             | highly controlled environments. We don't yet have
             | confidence about the exact mechanism on Earth but based on
             | those experiments it's likely (& generally currently
             | accepted as the most likely mechanism AFAIK) that the
             | boundary layer of volcanoes (probably underwater) + some
             | crucial initial elements being available causes life to
             | form "spontaneously". Given the elements required and their
             | overall availability in the universe, it's also highly
             | likely these conditions reproduce quite readily & life is
             | generally quite abundant. Similarly, significant levels of
             | intelligence within animals seems like quite a common
             | occurrence as well (great and lesser apes, elephants,
             | octopuses, dolphins, wolves etc). Whether or not
             | intelligence + physiological evolution + social evolution
             | to take advantage of that intelligence to build things
             | cooperatively is a huge unknown of course although I think
             | it's inevitable. On the other hand, how long life sticks
             | around on a planet once it forms is an open question - it's
             | not clear if a life ecosystem that's stable for billions of
             | years is likely and I suspect there's probably a small
             | amount of filtering that happens where planets become
             | inhospitable rather "quickly" and can't support life for
             | multiple billions of years (e.g. there were probably
             | several events in our history where it could have
             | collapsed).
             | 
             | Our type of society is probably much much rarer because you
             | need access to mineral and energy deposits to go through
             | each technological phase. For example, because of all the
             | mining we've done, if humanity were to disappear it's
             | highly likely the Earth would not sustain another
             | technological society because all the "easy to get to"
             | deposits of crucial metals & things like oil are gone and
             | there's no way to bootstrap a technological society (it's
             | possible other kinds of resources could be developed to
             | build other kinds of technology so who knows).
             | 
             | I think based on our existing body of knowledge, life is
             | likely extremely plentiful throughout the universe at one
             | point in time or another. Some form of intelligent life is
             | highly likely wherever we find any life that manages to
             | stick around through bilions of years. A highly
             | technological adept species of life though is highly likely
             | an extreme rarity and a planet gets one shot at developing
             | it. Whether any manages to escape their home planet remains
             | an open question that likely only we will manage to answer
             | over the next thousands of years if we make it that far.
        
               | ghaff wrote:
               | >Our type of society is probably much much rarer because
               | you need access to mineral and energy deposits to go
               | through each technological phase. For example, because of
               | all the mining we've done, if humanity were to disappear
               | it's highly likely the Earth would not sustain another
               | technological society because all the "easy to get to"
               | deposits of crucial metals & things like oil are gone and
               | there's no way to bootstrap a technological society (it's
               | possible other kinds of resources could be developed to
               | build other kinds of technology so who knows).
               | 
               | As I recall-though it's been many years-this was
               | something of a premise in Farmer's Riverworld series.
               | Once you've taken the first pass though historical
               | mineral etc. resources, you don't really get a second
               | pass.
        
               | antihipocrat wrote:
               | Readily obtainable hydrocarbons are lost for the
               | forseeable future. However, haven't we made it easier for
               | future civilizations to obtain minerals and metals? We
               | have extracted, refined and placed them all in
               | concentrated surface areas all over the planet (i.e. city
               | limits)
        
               | vlovich123 wrote:
               | Except a huge amount of it is alloys. You'd have to
               | reprocess it to extract out the raw materials which is
               | much harder than mining ore and requires a lot more tech.
               | Like things may be bronze plated but you're not going to
               | find a whole lot of bronze in 1 spot.
        
               | scythe wrote:
               | Wouldn't the next civilization just find itself mining
               | the remains of human cities? IIRC, the majority of the
               | copper ever extracted is _still in use_.
        
               | adolph wrote:
               | Cue Indiana Jones voice: you can't just mine that--it
               | belongs in a museum!
        
               | throwaway0b1 wrote:
               | > I think it's highly likely with lots of circumstantial
               | evidence that life is an evolutionary emergent phenomenon
               | where inorganic material reactions create life
               | 
               | Out of curiosity, if you reject religion, what other
               | possibilities are there?
        
               | seszett wrote:
               | Just inorganic material combining at random and
               | eventually, over about 10 billion years, randomly
               | creating something that self replicates in some way,
               | beginning the process of evolution through natural
               | selection and inevitably progressing to life as we know
               | it.
               | 
               | I don't think religion is needed at all for this. I also
               | don't think this has to be a common thing (after all,
               | here on Earth it only happened once, but it's also
               | possible that once life is widespread it makes it very
               | difficult for emergent new forms of life to take off).
        
               | wingspar wrote:
               | Where did you get 10 billion years of random chemistry?
               | 
               | The articles I read assert that life began just 500
               | million to 1 billion years after formation of earth.
               | 3.5-4.1 billion years ago with an earth age of 4.5
               | billion.
        
               | seszett wrote:
               | The universe is about 15 billion years old, and chemistry
               | didn't start with the formation of Earth.
        
               | wingspar wrote:
               | Chemistry in earth certainly started with the formation
               | of earth.
               | 
               | Are you suggesting that abiogenesis didn't start on
               | earth, but self-replicating molecules started evolving in
               | earths protoplanetary disc?
               | 
               | Serious question, haven't encountered that theory before.
               | It's kinda panspermia-lite.
        
               | lovemenot wrote:
               | I believe you may discussing at cross-purposes.
               | 
               | Presumably like your parent, I believed this was a
               | discussion about the probability that life has originated
               | elsewhere in the galaxy / universe, independently of life
               | on Earth.
        
               | mongoosled wrote:
               | Kurzgesagt did a video on this recently
               | https://m.youtube.com/watch?v=JOiGEI9pQBs
        
               | throwaway0b1 wrote:
               | Sorry, I meant possibilities other than "an evolutionary
               | emergent phenomenon where inorganic material reactions
               | create life"
        
               | furyofantares wrote:
               | Commenter is referring to the case where life is a common
               | occurrence as an "an evolutionary emergent phenomenon
               | where inorganic material reactions create life" in
               | contrast to the case where life has only happened once,
               | which would be more like an extremely lucky fluke where
               | inorganic material reactions create life.
        
               | brians wrote:
               | Simulation hypothesis: all this may be much younger than
               | we expect.
               | 
               | Nonuniform physics--call it colliding universes or
               | whatever, but the processes that gave rise to life on
               | Earth may not be possible anywhere in this universe now.
               | Including labs on Earth!
        
               | wingspar wrote:
               | >>>I agree it's an open question, but I think it's highly
               | likely with lots of circumstantial evidence that life is
               | an evolutionary emergent phenomenon where inorganic
               | material reactions create life. We already know that's
               | the case in highly controlled environments.
               | 
               | Did I miss some big announcements? Where has anyone
               | created life from inorganic material reactions in a
               | highly controlled environment?
               | 
               | Serious question, not trolling.
               | 
               | Seems to me that would be an insta-Nobel.
        
               | vlovich123 wrote:
               | I overstated that life from inorganic in a controlled
               | laboratory environment is what we have evidence for. What
               | we do have evidence for is organic compounds forming from
               | inorganic environments and we've shown certain kinds of
               | RNA can self-replicate.
               | 
               | Unless life originated directly at the formation of the
               | universe and panspermia is how life got to this planet,
               | the only logical explanation is that life somehow emerges
               | from "nothing". We don't know the exact mechanism and it
               | seems much more likely that life originates on a planet
               | rather than in space & arriving at a planet. The
               | "intelligent" panspermia explanation (i.e. aliens seeding
               | life throughout the universe to preserve it) would still
               | require an inorganic origin for life.
        
               | superposeur wrote:
               | This is what I referred to as "speculation" in the
               | literature for life's origins on Earth. This speculation
               | is a good first theoretical stab... or it might not be.
               | Until life is created from inorganic matter in a
               | laboratory (enabling us subsequently to estimate how rare
               | or not it might be elsewhere in the observable universe),
               | we should substantially dial back our confidence from
               | "life is likely extremely plentiful throughout the
               | universe at one point in time or another".
        
               | brokeAstronomer wrote:
               | I agree that we are limited to "speculating" due to n=1.
               | However, personally my sense is that simple life is more
               | likely to be ubiquitous than not. This is informed by the
               | fact that currently there is no evidence that conditions
               | on early Earth were particularly unique in comparison to
               | first principles modelling of rocky planet atmospheres**.
               | This coupled with the relative speed with which simple
               | life emerged points to it being a relatively probably
               | event, though we can't be certain. I expect that with
               | missions such as PLATO and the upcoming HWOs we'll have a
               | better sense of the conditions on mature Earth like
               | planets in the habitable zone. Though studying a large
               | sample of early Earth's shortly after formation may be
               | out of our reach for a while yet, depending on which
               | particularly mission gets chosen.
               | 
               | **Not my sub-field. Extremely complex models. Much is
               | still unknown.
        
               | vlovich123 wrote:
               | To me the simpler question is "if life didn't originate
               | from inorganic conditions somehow, what other explanation
               | is there? Life came into being with the creation of the
               | universe?". It's possible the latter explanation is what
               | happened, it just feels extremely unlikely. So the more
               | likely explanation is that life originates from inorganic
               | conditions. Then the question is where? Is it on a planet
               | or in space? Panspermia doesn't have a lot of traction
               | because the mechanism of action seems too complex to have
               | a good probability of success unless intentional (but
               | then you have a question of how did life that started
               | panspermia intentionally begin & you're back to needing
               | it forming spontaneously out of nothing).
               | 
               | And if "out of nothing" is the baseline condition, the
               | most likely explanation is that it happens where there's
               | a lot of energy to sustain it while not enough to kill
               | it, which means planets at the boundary of thermal
               | activity (since we need something more direct than
               | photosynthesis which is a relatively complex capability
               | that came late in Earth's cycle as far as we know).
        
               | ANewFormation wrote:
               | Taking a slight sidetrack to relativity, consider just
               | how absurd our universe is. To maintain the consistency
               | of the speed of light from all reference frames, time
               | (and 'real' distance) are instead the variables, and
               | there is every reason to believe this is correct. If you
               | didn't know this to be the actual case, it'd feel absurd
               | to even consider it.
               | 
               | Trying to intuitively and logically reason about
               | something with no answer in sight, all while assuming the
               | truths of our era, may ultimately be pointless.
               | 
               | Our universe, logical though it may be, plays by its own
               | rules, and many things will be simply irreconcilable
               | until those rules are further elaborated on.
               | 
               | As an aside the big bang also does not really answer the
               | prerequisite question of where the initial inorganic
               | matter/energy came from. The idea there being some sort
               | of a quantum fluctuation, which then begs the question of
               | its origin. I suppose it's just turtles all the way down.
        
               | throwaway290 wrote:
               | > To me the simpler question is "if life didn't originate
               | from inorganic conditions somehow, what other explanation
               | is there? Life came into being with the creation of the
               | universe?".
               | 
               | OK let's pretend to forget for a moment that we have no
               | definition for "life". Here is what we know:
               | - tons of examples of life turning into non-life
               | - zero examples of non-life turning into life         - a
               | crapton of non-life around us
               | 
               | Based purely on that evidence what do you think is more
               | likely: that non-life magically converts to life or, idk,
               | how about it started with life and all that non-life you
               | see is formerly life?
        
               | gls2ro wrote:
               | Hm what if you add a forth known:
               | 
               | - a lot of examples where life exists where we were
               | thinking it should not be possible
               | 
               | I think it raises a bit the idea that life is in a way
               | special and fragile at individual level but not that
               | fragile as a whole.
        
               | NotSammyHagar wrote:
               | I think you are taking the wrong tack in your approach to
               | this. You keep saying life must arise at the end of an
               | experiment. The thing we can do is work through to dna
               | base pairs arise. If you are then in the right
               | environment for random mixing of these base pairs for
               | millions of years, I do think you'll get microbes.
               | 
               | It's a big mistake to say we have to run an experiment
               | that produces living organisms from nothing to say we
               | know how it works. And that likely took millions of
               | years. That feels like an excuse to argue that it can't
               | happen without some external power (not the sun, ha).
        
               | fastball wrote:
               | I don't think inorganic material reactions can be
               | described as an evolutionary phenomenon.
        
               | SenHeng wrote:
               | It is evolutionary in the sense that the various
               | reactions slowly changes the make up of the environment
               | until the conditions necessary for life emerges.
        
             | idlewords wrote:
             | The other part of the open question is how easily life is
             | able to spread across worlds. This is why it's so vital to
             | go look at Mars without contaminating the search. If life
             | spreads easily (whether within the solar system or more
             | widely), then we'll likely find traces of life there that
             | look a lot like our own. If life arises easily, but doesn't
             | spread easily, we may find traces of very un-earthlike
             | biochemistry. And if life is rare, we'd expect to find
             | nothing.
             | 
             | Any of the three results would have huge implications. And
             | then rinse and repeat on Enceladus, Ganymede, Europa, and
             | so on. And find a way to look at exoplanet atmospheres and
             | chase stuff that comes in from outside the solar system.
             | Even negative results will add enormously to our
             | understanding.
        
               | addicted wrote:
               | At this point isn't Mars already contaminated?
        
               | idlewords wrote:
               | No, almost certainly not. There are individual living
               | microbes and spores on the various landers, but unlike
               | the microbiome that would travel with a human mission,
               | they're not viable and have no mechanism to get to
               | somewhere where they'd be viable.
        
               | RajT88 wrote:
               | I mean, you say that, but also this story was a thing
               | that happened:
               | 
               | https://www.cnet.com/science/sea-plankton-found-on-the-
               | outer...
        
               | vel0city wrote:
               | The leading theory is air currents from the planet slowly
               | contaminated the station over the decades, not
               | contamination before launch. It's also then still pretty
               | protected by radiation still being so close to Eath. Our
               | probes go through pretty tight clean room packaging, shed
               | almost all their outside layers before leaving Earth
               | orbit while still being very toasty, and then get blasted
               | by intense radiation for months and are finally separated
               | by some pretty massive distances on the planet.
        
             | creer wrote:
             | idlewords was specifically mentioning that we have (found
             | life elsewhere).
             | 
             | It was pretty clear to people that there would be no life
             | 750 metres inside the earth crust below another 700m of
             | ocean: too hot, no light, pressure, bla, bla. - And plenty
             | was found. Of course it's an easy counter "Still Earth,
             | haha! Doesn't count". So yes, it's back to the point that
             | whenever we have developped tech to go look, we have found
             | "whatever the tech could find". Except - for now - TV
             | serials radio waves. That's true. And bacteria on Mars. Yes
             | it's a glib way to put it but it's not an unfair answer to
             | that criticism.
        
             | NotSammyHagar wrote:
             | I went to a biology/astronomy talk where there was a
             | researcher working on the sequence of chemical changes on
             | the early earth without much water or atmosphere would need
             | to create dna base pairs. It was stunning because they
             | basically had a sequence of things and geological
             | discoveries point toward the precursor chemicals being
             | available. It's not that dna was just there.
             | 
             | This is not "life arising spontaneously". This is chemicals
             | in an environment where they eventually build dna base
             | pairs. Then after millions of years, perhaps you get
             | microbes and go from there. Meanwhile we are getting water
             | on earth from comets crashing down.
        
               | superposeur wrote:
               | The "eventually build dna base pairs" (that continue self
               | replicating) is the uncertain and possibly ludicrously
               | improbable step. See for instance
               | https://www.nature.com/articles/s41598-020-58060-0 which
               | argues for a probability per exoplanet small enough that
               | it hasn't happened a second time in the observable
               | universe. On the other hand, one of the self-organizing
               | proposals cited elsewhere in this thread may turn out to
               | be correct and the probability may be much higher.
               | 
               | The point is that, while there are some cool ideas on the
               | table, everything hinges on the particular value of this
               | probability (not just a qualitative story of how life
               | might have arisen) and we don't know what it is. Still
               | relevant: https://blogs.scientificamerican.com/cross-
               | check/pssst-dont-...
        
           | njoubert wrote:
           | Great comment! Indeed there is a recent Nature paper that's
           | causing a lot of discussion that is investigating that
           | missing link between the physics of matter and the emergence
           | of the natural selection and evolution processes that give
           | rise to life. this is a really fascinating area!
           | https://www.nature.com/articles/s41586-023-06600-9
        
             | creer wrote:
             | That link (going from basic chemical to bootstrapped
             | evolution) is an entire field of research. Not one paper
             | now and then. Labs, money, researchers building on each
             | other's work... Just want to point out.
        
               | dayjaby wrote:
               | Any good (starter) books on this?
        
               | creer wrote:
               | I have passed on the request to one of the scientists.
        
           | fastball wrote:
           | You call these factors "circumstantial evidence", but they
           | are only circumstantial evidence if our ideas about what
           | allows/causes/etc life are correct, which we have not
           | validated at all.
           | 
           | If we can't promote abiogenesis in a lab our understanding is
           | clearly limited, which is itself surprising. How many other
           | processes in nature have we observed and _not_ been able to
           | replicate ourselves (or at least make progress towards
           | replicating)?
        
           | donny2018 wrote:
           | "England has developed a hypothesis of the physics of the
           | origins of life, that he calls "dissipation-driven
           | adaptation."[3][5] The hypothesis holds that random groups of
           | molecules can self-organize to more efficiently absorb and
           | dissipate heat from the environment. His hypothesis states
           | that such self-organizing systems are an inherent part of the
           | physical world.[7]"
           | 
           | If Jeremy England's hypothesis is true, then life shouldn't
           | be unique but rather inevitable, as life in general would be
           | the way for matter to better dissipate heat, and better turn
           | low entropy into high entropy.
           | 
           | In fact, if you watch what life is doing in terms of physics,
           | then it's obvious that all it does is consume low entropy
           | (stored chemical energy, heat from heat baths), and
           | dissipates it around very efficiently.
           | 
           | Even we, humans are more and more good at it: we take
           | hydrocarbons chemical energy and turn it into work and heat.
           | It's not enough for us, we now consume energy stored in
           | atomic bonds, and turn it into work and heat. We capture
           | concentrated sunlight and also turn it into work and heat,
           | etc.
           | 
           | Essentially, we are doing what we are supposed to do as a
           | function of physical matter: we produce more entropy.
        
             | xorbax wrote:
             | I don't think that's Jeremy England's idea.
             | 
             | https://en.m.wikipedia.org/wiki/Entropy_and_life
             | 
             | Henry Adams first put it to print in the 1910s, and
             | Schrodinger did a fine turn on it and wrote a whole book in
             | the 40s.
             | 
             | The idea that life exists as the most efficient method to
             | facilitate thermodynamic equilibrium is older than the
             | neutron.
        
             | subroutine wrote:
             | It seems like a more fundamental phenomenon would be the
             | ability to self replicate. I imagine some organic compounds
             | forming a primitive vesicle in a relatively calm lagoon. As
             | the vesicle collects more organics it gets too large and
             | eventually blebs off a small vesicle (primordial fission).
             | The heartiest vesicles that can replicate fastest tend to
             | survive the longest and produce the most copies. Evolution
             | takes it from there.
        
             | noduerme wrote:
             | >> better turn low entropy into high entropy.
             | 
             | I took a double take and thought you'd made a typo, because
             | I've never heard that assessment before.
             | 
             | I see what you're saying about dissipating heat and work...
             | but life _organizes_. Most of that wasted heat from any
             | organism is the result of its processing, consolidating and
             | transmitting _information_. Which is probably the only
             | counter-entropic (extropic) process we can observe in the
             | universe. My view has always been that life _fights
             | against_ entropy.
        
               | donny2018 wrote:
               | >but life organizes
               | 
               | Yes, and that's the interesting part. In the right
               | circumstances, more entropy doesn't mean less complexity.
               | Matter can become more complex and less entropy locally
               | if that results in increase of total entropy in the
               | system. This can occur, for example, if we have constant
               | flow of concentrated energy on some local areas of the
               | environment that continuously wants to spread out.
               | Because the system as a whole "wants" to maximize its
               | entropy as fast as it can, and it statistically
               | "searches" for the shortest paths possible. This may
               | result in natural occurrence of more and more complex
               | molecules that dissipate heat more and more efficiently.
               | 
               | It's like the planet's atmospheric processes, for
               | example. Where differences in heat concentration don't
               | just spread out in linear gradients but can form complex
               | structures like vortexes, hurricanes or even stable
               | geometric hexagons (like the famous hexagon storm on
               | Saturn), etc.
               | 
               | >My view has always been that life fights against
               | entropy.
               | 
               | Yes, it "fights" against entropy to exist, but it exists
               | solely by processing low entropy into high entropy. Maybe
               | that's why it even exists in the first place?
               | 
               | This part is better addressed in Jeremy England's work,
               | for more basic explanations you can refer to videos like
               | 
               | this: https://www.youtube.com/watch?v=GcfLZSL7YGw (it's a
               | very good video on this topic by PBS)
        
           | tzimo wrote:
           | I would turn this argument around and say if life elsewhere
           | is more likely, than it should be more likely that life from
           | beyond has found us. If the likelihood of life elsewhere is
           | so high that it has to be true, to me it would also be true
           | that life should have found us by now
        
             | jamiek88 wrote:
             | I really don't think people are talking about intelligent
             | life here.
        
           | addicted wrote:
           | We've also found water on the moon.
           | 
           | And we know at least one Jupiter satellite has water.
           | 
           | So that's at least 4 bodies in the solar system that have
           | water and all the bodies where we have successfully landed
           | more than 1 rover have or had water (earth, moon, mars).
           | 
           | Every body where we could have discovered water, we have
           | discovered water. Seems like bayes theorem indicates that
           | water is also probably highly available in the universe.
        
           | hutzlibu wrote:
           | "we find evidence that life is more likely than expected"
           | 
           | But only after we really lowered our expectations in the
           | first place. I have an old book, about the Viking Mars
           | lander, describing the technical details, before the rover
           | succesfully landed on mars. It is full of optimism and a
           | strong expectation, that it will find evidence of at least
           | bacteria.
           | 
           | And before we had strong telescopes and rockets, there was a
           | strong expectation, that Mars has developed life.
           | 
           | We know, that bacteria can survive in stasis mode on
           | asteroids - yet we have not found life on any other planet.
        
             | kortilla wrote:
             | Those original expectations weren't based on evidence
             | though.
        
           | marcosdumay wrote:
           | > we find evidence that life is more likely than expected
           | 
           | The easy steps for abiogenesis keep getting easier and
           | easier.
           | 
           | Meanwhile, we keep having absolutely no idea of the
           | difficulty of the hard steps. Yes, technically that means
           | life is easier than we expected, by some completely
           | insignificant margin.
        
         | henry2023 wrote:
         | The universe is 13 billion years old.
         | 
         | Planet earth is 4.5 billion years old.
         | 
         | Life on earth started 3.7 billion years ago.
         | 
         | We sent our first radio wave just 125 years ago.
         | 
         | Probably life is not than unusual and we just don't have a way
         | to verify this (yet).
        
           | edgyquant wrote:
           | What is this probability based upon?
        
             | wredue wrote:
             | The probability is based on the fact that everywhere we
             | look, we find building blocks of life, life started on
             | earth basically as soon as it could have, life exists at
             | all and is capable of asking said question, life is
             | remarkably adaptable, we estimate billions of earth like
             | planets just in our galaxy.
             | 
             | I know that there is a burning desire to think we're
             | special, but the truth of the matter is that we're almost
             | definitely not.
        
               | mensetmanusman wrote:
               | We are the universe though. I.e. the universe has at
               | least one mind (yours) and it thinks that it is special
               | :)
        
           | borissk wrote:
           | The three and a half facts you listed (life may have started
           | earlier if it came to Earth from Mars or elsewhere) do not
           | logically lead to your conclusion.
        
         | fzeindl wrote:
         | I once heard: ,,The universe is unbelievably huge and
         | unbelievably old so rare events happen all the time."
         | 
         | I think it meant that even if life started itself accidentally
         | by some unbelievably slim chance, this could happen somewhere
         | else as well simply because the dice are rolled that often.
         | 
         | I think time is the factor here. When you take into account not
         | only the size of the universe but also it's age, the chance
         | that life started somewhere, somewhen and ended long ago could
         | be larger than zero, even if we are not able to calculate it.
        
           | grupthink wrote:
           | All dimensions are a factor. Life could exist on different
           | time-scales (e.g. it moves so slow we thought it was
           | inanimate). It could exist on different physical-scales (be
           | so large we don't realize we are a part of it). Or, it could
           | exist on an entirely different plane of existence (on a
           | desolate planet in a shard of silicon that is turing complete
           | and quietly simulating its own recursive universe).
        
           | onion2k wrote:
           | _I think it meant that even if life started itself
           | accidentally by some unbelievably slim chance, this could
           | happen somewhere else as well simply because the dice are
           | rolled that often._
           | 
           | That might be true, but we have no basis the probability of
           | how rare life is so we can't say it is. We may assume the
           | probability is high enough that it happens often in trillions
           | of chances, but if the probability is one in a quintillion
           | then we're simply wrong.
           | 
           | Humans are _incredibly_ bad at thinking about both
           | probability _and_ thinking about large numbers, so when we
           | combine the two we 're likely to be quite wrong.
        
           | NineStarPoint wrote:
           | Almost certainly there is more life out there somewhere. But
           | if the level of rarity is "for every billion years, it
           | happens once in every thousand galaxies" rare, then unless
           | FTL travel is real humanity will probably never get to see
           | it. And until we see a second example, we can't begin to
           | calculate the level of rarity.
           | 
           | But it's also not like we've looked at enough of our galaxy
           | to say it's rare either. We just don't know.
        
         | zvmaz wrote:
         | > It's worth remembering that there is not one single shred of
         | evidence that life has ever existed anywhere in the observable
         | universe but Earth.
         | 
         | It is hard for me to believe that in the mind boggling vastness
         | of space and time, we are the sole singularity in the history
         | of the universe.
        
           | hossbeast wrote:
           | Many things which are hard to believe are nevertheless true.
        
             | zvmaz wrote:
             | Sure, but in this case, we don't know.
        
           | local_crmdgeon wrote:
           | When Everest was first measured, it was exactly 29,000 feet.
           | 
           | They figured no one would believe this, so they told people
           | it was 29,002 feet
           | 
           | Sometimes things just are, regardless of what we expect.
        
             | clevergadget wrote:
             | Waugh is sometimes playfully credited with being "the first
             | person to put two feet on top of Mount Everest".
        
           | chrisandchris wrote:
           | The "observable" universe is very small. We can take a look
           | at things that are at the "ebd" of the universe, but those
           | happened multiple billion years ago. Earth itself is 2-3
           | billion years old and life in terms of mammals is is a couple
           | hundred million years old.
           | 
           | So to say, there may be another earth with human-like life.
           | But it's so far away, life isn't here (therefore not
           | observable) and life may already be gone there (but it will
           | take another billion years until we can observe it).
        
         | TheGRS wrote:
         | Sure, I don't think that's lost on anyone. The headline of
         | "life found outside earth" is going to be a big deal.
         | 
         | But I also think we are zeroing in on the inevitable outcome.
         | The math of probability and the simple components to life make
         | it seem pretty likely we'll get there unless there is something
         | more fundamental that hasn't been seen yet.
         | 
         | We haven't reproduced proto-life yet, but we also don't have
         | millions of years and a planet sized laboratory at our
         | disposal.
        
           | superposeur wrote:
           | Don't mean to pick on words, but your statement that "the
           | math of probability and the simple components to life" makes
           | life elsewhere an "inevitable outcome" proves my point that
           | the dialogue around this topic is currently distorted. The
           | probability of life arising from simple components is totally
           | unknown. Equally likely, sparking life requires a
           | combinatoric threading of a needle to the tune of 10^-25 even
           | when all ingredients are gathered in proximity.
        
         | sigzero wrote:
         | I happen to agree with you. I am in the "we are it" crowd but
         | still agree with should explore.
        
           | local_crmdgeon wrote:
           | I am too - I think it's the moon plus Jupiter that is
           | extremely unique and makes complex life possible
           | 
           | I also think it's a lot of pressure if it's only us, so it's
           | easier to imagine we're one of billions.
           | 
           | Honestly, honestly think it's just us. Maybe not in the
           | entire universe but in our local cluster.
        
         | swingingFlyFish wrote:
         | "It's worth remembering that there is not one single shred of
         | evidence that life has ever existed anywhere in the observable
         | universe but Earth"
         | 
         | Dude considering we're barely scratching the surface of the
         | scratch on the scratch of the surface, I'd say this is really
         | arrogant. We haven't found anything because our universe is a
         | haystack and we're looking for the quark of a needle in that
         | haystack. Perspective.
        
           | superposeur wrote:
           | This is true. It is also true that we have found "not one
           | single shred of evidence that life has ever existed anywhere
           | in the observable universe but Earth".
        
         | robofanatic wrote:
         | But the other possibility that some intelligent super being
         | created life on Earth is even bizarre. If that's what you
         | believe then who created that creator? You can go on and on,
         | there is no end to this question. That very first creator must
         | have come out from a "non living" thing.
        
           | DennisP wrote:
           | Your parent comment isn't suggesting creationism, just
           | pointing out that the beginning of life could be an
           | astronomically rare event.
        
         | mcfig wrote:
         | People are reacting negatively to your comment, the reason is
         | that however accurate your complaint may be about most such
         | reporting (IMO you are correct), you have chosen to attach it
         | to _this_ article. I find no evidence in _this_ article of
         | "tone implying life is about to turn up".
         | 
         | I think you have misread the tone. The article certainly has a
         | tone of excitement throughout. But it's excitement for further
         | knowledge, in general.
         | 
         | Of the possibility of life showing up elsewhere, it says only
         | this: "Scientists are still a long way from answering whether
         | life could originate on Enceladus"
        
           | superposeur wrote:
           | Fair enough. On the other hand, to my ear the title "NASA
           | finds life-sparking energy source and molecule" sets the
           | tone, as though life was sparked, or that we even know
           | _could_ be sparked by the presence of these ingredients with
           | some degree of confidence.
        
             | borissk wrote:
             | Life is much more than a mix of ingredients. A dead
             | bacteria cell has all the ingredients needed for life, but
             | is not alive.
        
             | mcfig wrote:
             | Good point, I had glossed over the title. That is
             | definitely clickbait, "life-sparking" is not the same as
             | "potential life precursor". The rest of the article seems
             | unusually restrained, though.
        
         | renewiltord wrote:
         | Is it actually worth remembering? I don't know, man. It kind of
         | sounds not worth remembering if I'm honest. It's kind of like
         | telling us that there is not one single shred of evidence that
         | artificial flight has ever existed or that exoplanets have ever
         | existed or anything of the sort.
         | 
         | Sure, that's the base case. It's not "worth remembering" at
         | all. It's as much worth remembering as the fact that my clothes
         | are in the dryer right now.
        
           | superposeur wrote:
           | I think it's "worth remembering" precisely because it seems
           | _not_ to be the base case anymore! To see this, just look at
           | all the expressions of confidence in life 's ubiquity
           | throughout the rest of this thread!
        
         | seanoliver wrote:
         | Life almost certainly exists elsewhere in the universe
         | (particularly if you consider that which is beyond what we
         | define as "observable"). As others have commented, it's too
         | large for it not to exist.
         | 
         | However, it does seem extremely rare and could be so rare that
         | it doesn't exist in the observable universe (it's almost
         | certainly not in our Local Bubble).
         | 
         | It is interesting to also think about the likelihood of
         | "intelligent" life. Because while basic, simple organisms are
         | bound to appear somewhere else considering the universe's
         | vastness, the idea that they could develop this intelligence
         | and self-awareness is another big leap that doesn't seem like
         | it necessarily needs to happen wherever life is happening.
        
         | richardw wrote:
         | We're looking for the shreds of evidence. What would you prefer
         | people do?
        
         | bvirb wrote:
         | What a fun thread. I've always heard this as one of The Great
         | Filters related to the Fermi paradox. FWIW the wikipedia for
         | the Fermi paradox even mentions that:
         | 
         | > The most commonly agreed-upon low probability event is
         | abiogenesis
         | 
         | ...which I read as saying that the most commonly agreed-upon
         | reason we haven't found life anywhere else yet is because we
         | _are_ special and abiogenesis is the rare event (the great
         | filter).
         | 
         | All the various great filter theories are pretty fun reading.
        
         | qqtt wrote:
         | > Moreover, no one has succeeded in hatching living matter from
         | non living matter and we must honestly say we do not know how
         | this process came about or the faintest estimate of how likely
         | it is to occur (despite much speculation
         | 
         | Just want to comment on this point. The research in this field
         | is pretty esoteric. It doesn't really benefit us to understand
         | how this process came about (ie, there is little practical gain
         | here, no medical advancements or otherwise), and moreover it
         | requires a simulation which can estimate behavior over hundreds
         | of millions of years. The usefulness of cracking the early
         | earth/life creation part of our history is really not
         | immediately clear, and thus research is limited.
         | 
         | That said, the Miller-Urey experiment
         | (https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment)
         | showed animo acids organizing over conditions similar to early
         | earth, and a follow up experiment dubbed Planet Simulator
         | (https://en.wikipedia.org/wiki/Planet_Simulator) was extended
         | to show the organization of protocells as part of this early
         | earth environment.
         | 
         | It seems only a matter of time before science can connect the
         | dots along the rest of the hundreds of millions of years
         | regarding this process to show the line between chemical young
         | earth evolving to be biological.
         | 
         | As an aside, why do you think it is "important to remember"
         | that we haven't found life or that we don't fully understand
         | the process by which biology evolved from chemistry? Why
         | exactly is it "important to remember" such things?
        
           | superposeur wrote:
           | It is "important to remember" precisely because these days
           | people are not remembering this and speak with a sense of
           | inevitability about discovering life elsewhere, which sense
           | of inevitability is totally unsupported. I may gently point
           | out, your own post says "it is only a matter of time before
           | science can connect the dots", reflecting this (in my view)
           | distorted sense. The abiogenesis research you cite is
           | absolutely worthwhile, but it is not even clear if it is in
           | the right direction and certainly far, far from successfully
           | sparking the sustained chain reaction of life. To my eye,
           | equally consistent (as some different research may suggest)
           | is that a combinatorial needle must be threaded to the tune
           | of p < 10^-23 per exoplanet, making it unlikely to happen
           | again in our observable universe.
           | 
           | Edit: to cite just the one "combinatorial abiogenesis"
           | reference, see for instance
           | https://www.nature.com/articles/s41598-020-58060-0
        
             | qqtt wrote:
             | > It is "important to remember" precisely because these
             | days people are not remembering this and speak with a sense
             | of inevitability about discovering life elsewhere
             | 
             | Could you expand on this a bit. Whether someone speaks with
             | a sense of inevitability or not, why is it important either
             | way? Why is it "important" to remind people we haven't
             | (yet) found life on other planets?
             | 
             | Why are the existing gaps in abiogenesis "important" to
             | point out?
             | 
             | What is so "important" about these things?
        
               | superposeur wrote:
               | Well, first, I take it to be an axiomatic goal of science
               | to believe that which is true, disbelieve that which is
               | false and to be agnostic about things we have no evidence
               | about; I.e to calibrate our model of world to the world
               | as it is.
               | 
               | But, further, I've seen what happens when a subfield
               | reports its findings in a way that misleadingly raises
               | expectations of a titanic discovery just around the
               | corner. When the discovery fails to materialize, over-
               | optimism curdles into its opposite, over-cynicism. Better
               | to calibrate expectations accurately -- slow and steady
               | wins the race.
        
         | ryanSrich wrote:
         | The math is the evidence. The math is not in your naysaying
         | favor.
        
           | verisimi wrote:
           | I can't even conceive what evidence maths could provide!
        
         | mdavidn wrote:
         | What you say is true, but thinking of ourselves as the only
         | life feels like hubris. It reminds me of geocentrism.
        
         | troyvit wrote:
         | Personally I think articles like this are actually the shreds
         | of evidence you say don't exist.
         | 
         | If there isn't life on Enceladus this is still incredibly
         | exciting because then it might make the perfect lab for us to
         | put life and study how it evolves.
        
         | nescioquid wrote:
         | I think you enjoy the top comment for the phrase
         | 
         | >> It's worth remembering that there is not one single shred of
         | evidence that life has ever existed anywhere in the observable
         | universe but Earth.
         | 
         | There is nothing like the blunt expanse of a simple fact to
         | sharpen the mind. If the consequent should be that, based on
         | the evidence we are alone and therefore first, I postulate an
         | obligation to seed the cult of Apollo throughout the universe
         | -- the god of the one thing without which life itself would be
         | a mistake.
         | 
         | I leave it to HN to fuck up the answer.
        
         | verisimi wrote:
         | What you are touching upon, imo, is the idea that science is
         | NOT actually some independent, objective means of understanding
         | the world, in contrast to religious thinking. Whereas the
         | reality is that science is actually a belief based system, that
         | cloaks itself in a (thin) veneer of objectivity. The scientific
         | method is venerated but not applied personally.
         | 
         | So, the reality is that adherents accept a reality
         | intermediated for them by priests/scientists (and journals,
         | trusted sources). Adherents talk about truth/reality while
         | having little or no personal experience of the matter at hand.
         | It is group behaviour, evidence is paid lip service to but
         | there is very little critical thought or assessment of said
         | 'evidence' by any individual adherents. When the scientific
         | authorities make a pronouncement, this is simply accepted.
         | 
         | Religion. Believers.
        
         | berniedurfee wrote:
         | But we barely know anything about how life on our own works,
         | much less came about. We barely know anything concrete about
         | anything.
         | 
         | We're just hairless (mostly) apes running amok having
         | discovered how to trap fire inside little bits of copper and
         | sand.
         | 
         | We'll look as primitive to our descendants in 10,000 years as
         | our ancestors of 10,000 years look to us.
         | 
         | I guess I'm saying that, I think, our views on the universe and
         | life are only very slightly more accurate than they were when
         | those ancestors were painting what they saw in caves.
         | 
         | I think our hubris tells us we understand far more than we do.
         | I think if you take that into account, the possibility for life
         | existing elsewhere in the universe is an absolute fact.
         | 
         | I surmise, that for us to think that we're the only sentient
         | life in the unimaginably vast universe is the ultimate
         | manifestation of our drive for self-preservation.
         | 
         | We want to survive and propagate our DNA above all else,
         | therefor we must be vigilant against all threats, therefor if
         | we consider ourselves at the center of the universe, we can be
         | sure to never neglect anything that might indeed be a threat.
         | 
         | The problem with this instinct is that it clouds our conscious
         | judgement into thinking that the universe does indeed revolve
         | around us and then we make conclusions according to that
         | fallacy.
         | 
         | I think life in the universe is as ubiquitous as rocks. It's
         | everywhere in all manner of forms and sophistication. We just
         | won't have the tools to see or hear it for maybe a couple
         | hundred years or so. But once we do, we'll have a chuckle at
         | how we could be so arrogant as a species to ever think we were
         | alone.
        
       | 725686 wrote:
       | For anyone interested in the origin of life, and the origin of
       | complex life I highly recommend Nick Lane's Books. You can start
       | with "The Vital Question". There are also some fantastic videos
       | of him online.
        
         | borissk wrote:
         | Yes, Nick Lane has done a great job of popularizing the
         | metabolism first hypothesis of origin of life. What his books
         | and videos don't address is the biggest problem of metabolism
         | first - once there's a proto cell (say inside a pore within a
         | white smoker) with working metabolism that turns H2 and CO2
         | gases into sugars and other organic molecules - how are the
         | proteins that make the metabolism work translated and encoded
         | into an RNA code.
        
         | yoble wrote:
         | Seconding this, as a layman I've found his books both technical
         | and fascinating. He's a great teacher, getting into the details
         | but explaining in a really engaging manner.
        
       | mekoka wrote:
       | I think the title is pushing it a bit. When I see "life-sparking
       | energy source", I think of an inextricable property. Get that and
       | you can spark life. But we have and we couldn't. They're merely
       | ingredients, building blocks, fuel to _sustain_ life as we
       | understand it on Earth, as the article more sensibly admits. The
       | "life-sparking" source itself remains a mystery.
        
         | dwaltrip wrote:
         | Instead of something extricable, I imagine a series of
         | processes that, due to specific conditions, results in some new
         | process that has distinctly different characteristics from the
         | originating process.
         | 
         | E.g. snowpack melt -> mountain stream -> waterfall
         | 
         | A waterfall is a vastly simpler system than a living organism,
         | but I wouldn't be surprised if the origin of life has a flavor
         | similar to waterfall formation.
         | 
         | I like the idea that all phenomena we observe are emergent in a
         | similar way.
        
       | CrzyLngPwd wrote:
       | We don't know what causes life.
        
       | bytearray wrote:
       | I always thought Enceladus was just an icy moon, but turns out
       | it's cooler than that.
        
         | gitaarik wrote:
         | Warmer you mean?
        
       | holoduke wrote:
       | The fact that there is something, just something can drive me
       | crazy. Why is there something and not just nothing.
        
         | tigerlily wrote:
         | I feel the same way you do. It drives me even crazier that more
         | people don't feel this way.
        
           | ryanSrich wrote:
           | The simple answer is the controversial answer. Life needs
           | something to spark it from nothing to something. That's more
           | evidence of a demiurge than anything else.
        
             | jamiek88 wrote:
             | What made the demiurge?
        
               | ryanSrich wrote:
               | If we're just having fun here, then I'd say it doesn't
               | have a creator. Which is not a concept humans are capable
               | of understanding. It could be the demiurge is eternal,
               | forever and always. The concept of time may have been an
               | invention by such a creator.
        
               | NineStarPoint wrote:
               | Sure, but time isn't necessary for a causal chain. Even
               | if from the perspective of the demigurge it has always
               | existed, in some causal (or anti-causal depending on the
               | laws outside our reality) way it must have spontaneously
               | come in to being (Or, if the demiurge was created from
               | another being, eventually the chain of causation comes
               | back to some being spontaneously coming into existence).
               | You can't avoid the "something came from nothing"
               | reality, even if what came into being first came into
               | being in a way that from a human perspective seems
               | timeless.
        
               | jdthedisciple wrote:
               | The human perspective is not the correct/absolute
               | reference frame.
               | 
               | The Creator must not have "come from nothing". Him always
               | existing as the ultimate entity - even before/outside the
               | existence of time itself - is not difficult a concept for
               | us to grasp.
        
         | mensetmanusman wrote:
         | It's a beautiful question. You can reason a bit from knowing
         | there is something instead of nothing, when nothing is clearly
         | an option :)
        
         | NineStarPoint wrote:
         | In the end, if you go all the way back through the chain of
         | causation (whatever causation even looks like outside of the
         | bounds of reality we know within our universe), whatever it is
         | that resulted in our universe (whether it be the big bang or a
         | god or alien that created the bing bang or a higher being that
         | created said god or alien)...at some point, something must have
         | come from nothing. It's the only inevitable truth, and it
         | drives me crazy too.
        
           | Qwertious wrote:
           | Unless the universe _always existed_. Why should there be
           | nothing and not something?
           | 
           | And don't say "entropy". For all we know, the big bang
           | occurred after a previous heat death.
        
           | 2Pacalypse- wrote:
           | Isn't this only true if there is no physical infinity? I know
           | it's-turtles-all-the-way-down is impossible for our brains to
           | comprehend, but causality breaks down when infinities are
           | involved. Another thing is that if space-and-time itself was
           | born at some point (as they say), then talking about "before"
           | and causality doesn't make any sense either.
           | 
           | But yeah, to your point, thinking that there was never
           | "nothing", and that there always was "something" is equally
           | mindblowing.
        
           | Jeff_Brown wrote:
           | I don't see why it should feel bothersome.
           | 
           | To ask what came before the first moment is to apply a
           | concept, time, where it no longer applies.
           | 
           | Similarly, suppose you knew everything. No matter what it
           | was, how much information it was, you'd still be able to ask,
           | "What's beyond that?" But being able to form those words
           | doesn't imply the question means anything.
        
         | ajmurmann wrote:
         | There is this super cool phenomenon where pairs of matter and
         | antimatter will spontaneously come into existence in a vacuum
         | and then neutralize itself. I always liked to intuitively
         | connect that with an equation that looks really complicated,
         | but just comes out to 0 = 0 when you simplify it. Add to that
         | cellular automata that based on extremely simple rules can show
         | mindblowing outcomes. I feel these things together give an
         | intuitive feeling about a possible origin of this something we
         | are looking at. I think Steven Wolfram voiced similar thoughts.
         | Of course one might go further and ask why laws of physics
         | exist at all...
        
           | dieselgate wrote:
           | You mentioned some good things but also cast a large net. Are
           | you referring to the Casimir Effect? Am just vaguely familiar
           | with some of the general concepts but very much recommend
           | this video on the topic, by a Prof/physicist
           | 
           | "Casimir Effect and Black Holes"
           | https://www.youtube.com/watch?v=IRcmqZkGOK4
        
             | ajmurmann wrote:
             | Yeah, reading about the Casimir effect seems like that's
             | what I remembered. I hadn't read about it since it was
             | covered in high school 20+ years ago. And yes, this entire
             | line of thought is more an intuition than even a theory.
             | But having something at all appear in a vacuum and seeing
             | how complexity can arise from very simple rules is such an
             | inspiring combination to me.
        
       | rqtwteye wrote:
       | I really, really, really hope we will discover life on another
       | planet, preferably in another solar system. Right now we have a
       | sample size of one so a lot of thinking about the origin is
       | speculation. I hope this will change.
        
         | echelon wrote:
         | I always like to daydream about the various solutions to the
         | Fermi Paradox.
         | 
         | If we're not early, if life isn't rare, and there are
         | intelligent species [1], what might most of it look like?
         | 
         | I don't think most of them would match the techno signatures
         | we're familiar with. Factories, gas emissions, etc. are an
         | industrial age thing.
         | 
         | What if they're _really_ smart? What does that look like? What
         | kind of signals might we detect? What kinds of energy might
         | they be harnessing?
         | 
         | Are there any good reads or papers that posit these things?
         | 
         | [1] I also imagine they've found a way to escape the
         | limitations of intelligence and death, perhaps by becoming
         | computers of some kind.
        
           | hotpotamus wrote:
           | I wonder if any sentient being would really want to live
           | forever. What would there be to look forward to as the
           | galaxies recede out past the cosmic horizon and all the stars
           | shutdown? What would be the point? Just wait around in the
           | dark until the heat death gets you? I sometimes suspect that
           | simple nihilism is the answer to the Fermi Paradox.
        
             | echelon wrote:
             | With all the compute and energy available at that stage,
             | perhaps there are more possibilities than we can currently
             | see or imagine?
             | 
             | I sometimes like to think that we ourselves are actually
             | the memories of a distant descendant. Maybe it reversed the
             | light cone and was able to replay everything with exacting
             | precision. Maybe it's studying and musing over its humble
             | beginnings. (It might get a laugh that we're communicating
             | this to one another.)
        
               | hotpotamus wrote:
               | I used to be a bit perturbed by the thought of living in
               | an ancestor simulation, but then I figured if that's my
               | reality, then I suppose it is what it is.
               | 
               | It seems like a long time since there have been any
               | really game-changing breakthroughs in theoretical
               | physics. I'd be a fool to say that that means that there
               | aren't any more to be had, but it does seem more like
               | we're just sort of fiddling around with a few refinements
               | and there might not be anything huge left. As you say,
               | maybe a greater intelligence than what we've got can
               | figure it out, but that does go back to Fermi - if they
               | could do amazing things like enclose a star or travel
               | interstellar distances, then why haven't we seen them?
               | 
               | What if it's all just protons, neutrons, and electrons
               | (and some other less important particles presumably) plus
               | a bunch of energy out there? Would a super-intelligence
               | really be interested in seeing more of them?
        
           | rqtwteye wrote:
           | "I also imagine they've found a way to escape the limitations
           | of intelligence and death, perhaps by becoming computers of
           | some kind."
           | 
           | I am 100% convinced that this is in our future, not even very
           | far out. Why put up with our flawed bodies if we don't have
           | to? First we will probably replace parts of the body with
           | something better until eventually the whole body has been
           | replaced.
        
             | HaZeust wrote:
             | I think it's most likely we won't get "upgraded", but
             | rather cloned into computers. I think the essence of
             | ourselves, the original, will stay within the vessel of our
             | body - and doomed to the flaws therein. But, our
             | personalities will be able to be carefully cloned (likely
             | using a ton of questions fed to AI, or otherwise) in
             | essentially infinite AND limitless computers.
             | 
             | It's a scary thought, to be sure. That, no matter how close
             | a computerized copy of me is _to me_ ; I'm still stuck in
             | this body, in this own brain, and its inevitabilities.
        
         | iAMkenough wrote:
         | Your Amazon Prime membership includes a variety of space
         | shipping benefits, including several space shipping options if
         | you need to expedite your discovery.
        
       ___________________________________________________________________
       (page generated 2023-12-17 23:02 UTC)