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NASA study finds life-sparking energy source and molecule at Enceladus

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Re: NASA study finds life-sparking energy source and molecule at Enceladus

#171

Post by throwaway290 »

vlovich123 wrote: post #126
brokeAstronomer wrote: post #118

Earlier quoted context omitted.

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 t…

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? Pansperm…

> 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?

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#172

Post by dieselgate »

ajmurmann wrote: post #163
holoduke wrote: post #84

The fact that there is something, just something can drive me crazy. Why is there something and not just nothing.

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…

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

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#173

Post by SenHeng »

fastball wrote: post #116
vlovich123 wrote: post #54

Earlier quoted context omitted.

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…

I don't think inorganic material reactions can be described as an evolutionary phenomenon.

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.

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#174

Post by donny2018 »

noduerme wrote: post #167
donny2018 wrote: post #123

Earlier quoted context omitted.

“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…

>> 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 o…

>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)

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#175

Post by chrisandchris »

zvmaz wrote: post #30
superposeur wrote: post #6

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…

> 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.

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).

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#176

Post by NotSammyHagar »

superposeur wrote: post #23
idlewords wrote: post #22

Earlier quoted context omitted.

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 ba…

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.

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.

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#177

Post by NotSammyHagar »

superposeur wrote: post #90
vlovich123 wrote: post #54

Earlier quoted context omitted.

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…

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 t…

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).

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#178

Post by Qwertious »

NineStarPoint wrote: post #160
holoduke wrote: post #84

The fact that there is something, just something can drive me crazy. Why is there something and not just nothing.

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 trut…

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.

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#179

Post by 2Pacalypse- »

NineStarPoint wrote: post #160
holoduke wrote: post #84

The fact that there is something, just something can drive me crazy. Why is there something and not just nothing.

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 trut…

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.

Re: NASA study finds life-sparking energy source and molecule at Enceladus

#180

Post by vel0city »

RajT88 wrote: post #153
idlewords wrote: post #148

Earlier quoted context omitted.

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.

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...

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.
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