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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

#61

Post by superposeur »

spenczar5 wrote: post #44
superposeur wrote: post #36

Earlier quoted context omitted.

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 t…

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.

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!

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

#62

Post by renewiltord »

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…

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.

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

#63

Post by idlewords »

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.

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.

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

#64

Post by mekoka »

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.

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

#65

Post by creer »

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.

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.

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

#66

Post by local_crmdgeon »

dragonwriter wrote: post #58
local_crmdgeon wrote: post #53

Earlier quoted context omitted.

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

> 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.

Apparently you are correct!

https://www.catholic.com/qa/whats-the-catholic-position-on-t...

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

#67

Post by superposeur »

yieldcrv wrote: post #55
superposeur wrote: post #43

Earlier quoted context omitted.

No is declaring that there is no needle in the haystack. Please actually read my post.

absence of evidence is not evidence of absence sorry your life has created this crusade of rhetorically reminding people about the absence is evidence

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.

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

#68

Post by grupthink »

fzeindl wrote: post #29
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…

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…

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).

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

#69

Post by seanoliver »

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…

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.

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

#70

Post by onion2k »

fzeindl wrote: post #29
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…

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…

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.

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