billions-of-potentially-habitable-planets

[mutleyeng]

im not sure that really answers my question ebura,
i find it hard to conceive how any distinction could be make without a sample of the very earliest incarnation of both.

I am not talking here of interstellar transfer...i agree entirely that is extremely unlikely, which is why my personal opinion is that study of exo planets is the best way open to us to answer that question. That or we just get really lucky by stumbling across phosphorus based life or some such thing.

[eburacum45]

i find it hard to conceive how any distinction could be make without a sample of the very earliest incarnation of both.

Try this article;
The Molecular Clock
http://en.wikipedia.org/wiki/Molecular_clock
Using phylogenetics and protein chemistry it is possible to determine roughly how long ago any two species diverged from each other (with a certain amount of uncertainty, which is also discussed on that page).
A species from another planet would share no ancestors with any species on our world, so this method could not obtain a realistic value for the date of divergence.

[mutleyeng]

sure, but hands up who thinks life on earth began as DNA?
as i said very early on, i dont know much about biology, and i really hope they would be able to demonstrate it as you suggest, but if we do not have early enough samples of primative early earth life, then you are going to need to be able to establish time frames for life that will be really difficult to establish.
To my untrained eye it just seems a minefield of potential unknowns. But i hope i am just being ignorant...more than possible

I think it would be a great deal easier to demonstrate that life on another planet was related, than it would be to demonstrate that it deffinately wasnt.

added:
i dont even really see the conflict here. the study of exo-planets is furthering our knowledge greatly regardless of the life issue.
We knew next to nothing about system formation before we looked at exo planets. Now we still know next to nothing, but a lot more than we did. We have found sytems that we thought were impossible, like planet formation around biary systems.
to study their atmospheres will just as likely add to our knowledge of planetary formation. compared to manned exploration, this is cheap science

[eburacum45]

I think it would be a great deal easier to demonstrate that life on another planet was related, than it would be to demonstrate that it definitely wasn't.

If we do demonstrate a relationship between life on another world and life here, that would be a very significant result; but in most, if not all, cases, there would be no relationship. Quite likely there would be very little overlap in biochemistry. Alien life might not use DNA at all, or might express it in an entirely unrelated way.

Of course we couldn't determine any of this without actually getting our hands on actual alien samples. I can't imagine any way to do molecular biochemistry via telescope.

[Rhaedas]

sure, but hands up who thinks life on earth began as DNA?

Nope, it was much simpler than DNA. It's still a new science with lots of questions to answer, but there's plenty of reason to think that life started here on Earth.

as i said very early on, i dont know much about biology, and i really hope they would be able to demonstrate it as you suggest, but if we do not have early enough samples of primative early earth life, then you are going to need to be able to establish time frames for life that will be really difficult to establish.

We have very old fossilized traces of life's activities. Not the organisms themselves, but their processes left marks that are distinguishable from geologic events.

I think it would be a great deal easier to demonstrate that life on another planet was related, than it would be to demonstrate that it deffinately wasnt.

Agreed. A match, just like DNA tests, says a lot. Chances are that even if life elsewhere followed similar steps in growth, it will have distinct differences.

i dont even really see the conflict here. the study of exo-planets is furthering our knowledge greatly regardless of the life issue.
We knew next to nothing about system formation before we looked at exo planets. Now we still know next to nothing, but a lot more than we did. We have found sytems that we thought were impossible, like planet formation around biary systems.
to study their atmospheres will just as likely add to our knowledge of planetary formation. compared to manned exploration, this is cheap science

Any new knowledge, even if it brings new questions, is good knowledge. I'm very encouraged that the Kepler budget was extended. And even if we find some things that are the same, that's good data too. But we probably won't...look at our own solar system. Before we started looking we thought one planet or moon was like another. Every body we visit has uniqueness as well as similarities. It's all good science.

[mutleyeng]

reply to eburas points:
for reason you have already given, you wouldnt need to do it by telescope for exo planets to reasonably conclude it was unrelated.
would it be very sigificant to demonstrate a relationship between life on two worlds?
im sure it qould be interesting...not sure i would have learnt anything fundimental from it. i already know life can survive in space, i aleady know rocks can migrate between planets.


added,
i do acknowledge you may learn a great deal about lifes development from two sperate planet, but related life.when i question if i would learn anything fundimental from it, i am meaning cosmolgical. i conceed it may have great value to biology

[eburacum45]

Well, i wouldn't be that surprised if life on Mars (or Europa, or Titan) turned out to be distantly related to Earth Life. If it was, that wouldn't really tell us much about life in other systems.

On the other hand, if life in two widely separated solar systems turned out to be related, I'd favour deliberate (or accidental) dispersal by some advanced civilisation at some time in the past. Natural interstellar panspermia is so unlikely that the artificial hypothesis would start to look very favourable by comparison.

[mutleyeng]

Nope, it was much simpler than DNA. It's still a new science with lots of questions to answer, but there's plenty of reason to think that life started here on Earth.



We have very old fossilized traces of life's activities. Not the organisms themselves, but their processes left marks that are distinguishable from geologic event.

.

any suggested reading material to clue me up better on this?
i am really unclear on just how much is known (hypothesis) about very early life. i know rna is often spoken of, but what i am interested in is how we could trace that through to dna life. also in what is known about the transition from organic chemestry to biology.
also interested in anything discussing why our life is tied to earth origins.
im quite happy to acknowlege what i know may be very mis guided...like i say, im just a lay person.

[Rhaedas]

Abiogenesis is the term you're looking for, and I'm no expert either on it, as there's several schools of thought on what might have happened. However, a good start as always is Wikipedia, http://en.wikipedia.org/wiki/Origin_of_life. Specifically down to "Current Models". One name mentioned on there is Jack Szostak, and there's a good video on Youtube about his ideas of simple organic replicators. http://www.youtube.com/watch?v=U6QYDdgP9eg

And I'm sure there's a few real expert here that can add more, and/or critique what's on those links.

[mutleyeng]

thanks for the link.
yes, ive googled abiogenesis a good number of times.....there is so little on it its frustrating.
the problem i guess i have is this subject engages me from a cosmological perspective rather than a biological one, so it is fascinating to find out just how an astrobiologist might go about trying to distinguish different trees of life with so little data of life when abiogenesis may have happened.
what you said of the biochemical signitures in our oldest rocks is interesting, but the big question is, are they early enough i guess

[Rhaedas]

http://www.sciencedaily.com/releases...0821205241.htm

Here's a link to the story on the ancient bacteria found in Australia. Dated 3.4 billions years old, but the really important thing is that these were still complex organisms compared to very early life. So if they were around only a billions years after the Earth first formed, then that narrows the time period that life could have started. It might have been an explosion much like the Precambian, where there was nothing, and then everywhere very quickly (geologically speaking).

[mutleyeng]

thats great thanks,
ive just been googling astrobiology and finally they are starting to come out from under their rocks and talk about what they are up to.
will have a read of the story you linked. dosnt it make you wonder though, that billion year gap from formation to known life is the same billion yr period that Mars is believed to have been warm and wet

[swampyankee]

any suggested reading material to clue me up better on this?
i am really unclear on just how much is known (hypothesis) about very early life. i know rna is often spoken of, but what i am interested in is how we could trace that through to dna life. also in what is known about the transition from organic chemestry to biology.
also interested in anything discussing why our life is tied to earth origins.
im quite happy to acknowlege what i know may be very mis guided...like i say, im just a lay person.

You could start here, at the Talk Origins site.

[Colin Robinson]

That matters a lot to me. Intelligent life will talk
with us and tell us about all the worlds they know,
and all the ideas they know.

Why should they?

After all, there are highly intelligent earthlings who argue that it would be a serious mistake to send out messages revealing our existence to alien civilizations whose technology and intentions are unknown to us. Why wouldn't aliens reason the same way?

The possibility does exist that their methods of observation are so advanced that they know all about our technology, and have concluded that we are much too primitive to pose any threat. But even if they know what technology we have today, how could they know what technology we'll have tomorrow?

[Jeff Root]

That matters a lot to me. Intelligent life will talk
with us and tell us about all the worlds they know,
and all the ideas they know.

Why should they?

Because they want to.

If they didn't want to, they wouldn't have contacted us,
and we wouldn't know they existed. The only intelligent
extraterrestrials we can discover are those who want to
talk with others.

What are you doing here?

After all, there are highly intelligent earthlings who argue
that it would be a serious mistake to send out messages
revealing our existence to alien civilizations whose
technology and intentions are unknown to us. Why
wouldn't aliens reason the same way?

They might, for a while. That could get boring after a
few million years, though, don't you think? Never talking
to anyone because you are afraid of what you imagine
they might do to you if they knew you existed? Maybe
even just a few thousand years. Or a few hundred.

The possibility does exist that their methods of observation
are so advanced that they know all about our technology, ...

That is possible only if they currently have observers in
our Solar System.

... and have concluded that we are much too primitive to
pose any threat.

That is already certain. There is no way we could pose a
threat to any civilization capable of communicating with us.

But even if they know what technology we have today, how
could they know what technology we'll have tomorrow?

They have been around for millions of years. They have
the ability to communicate with us, even though we have
only just recently learned how it can be done, and have
yet to do it. They must have had the ability for most of
the lifetime of their civilization. Millions of years. They
must have used that ability, or they would have lost it.
So they have learned from thousands of other civilizations
with a cumulative experience of billions of years.

They know what to expect.

-- Jeff, in Minneapolis

[Selfsim]

what have you learnt from a null finding? what "habitable zones" do we know of locally...other than on earth?

A null finding in a 'Habitable Zone', would tell us for instance, that maybe our habitability criteria require modification. Or say, depending on the habitat of a non-discovery, there may be some obvious reason for the non-finding of exo-'life', which we can also add to the definition of where to spend less time looking within those 'Habitable Zones'.

Some local habitable zones have already been mentioned by others .. Europa, Mars, Enceladus, Titan, etc.

Its discovery (or verification) over light-year distances, is not feasible in practice .. we already know this .. no verifiable progress towards the definition of 'habitable zone' is achievable, because exo-life cannot practically be confirmed following some instance of exo-atmospheric gas detection.

can you demonstrate to me that this is true? I appreciate we do not currently have the hardware to do analysis of exo planet atmospheric conditions right now, but my approval of the quest is that the ability to do so is not beyond known technology.

The presence or absence of a technology is not what I see as being a big issue. There are also physical limits these technologies are up against, which seem to be easily passed off as 'present technology' limits. Technologies are also constrained by Physical Laws. There are also hard limits outside of which, any such technology is unable to function. The generalised idea that such limits can be removed by human design, innovation, resource and sheer will, is not a hard and fast Law of nature. There seems to be some kind of generalised idealistic belief, that humans can always go on doing this. There are shades of grey in this argument, so I would not accept a generalised assertion in this regard, without specifics.

Demonstrating what I say is true: Inferring exo-life from the presence of atmospheric gases is still by inference only. I am referring to verification of exo-life, which requires that an exo-life specimen be modelled. In order to do that, we have to have examined in detail, the 'metabolic processes' (or optical reflection properties of) en-masse exo-life instances. This simply cannot be done, if we have never discovered a single exo-life instance, nor if we have no hard data from anywhere else about other than earth-life 'metabolism', (nor exo-life optical reflective properties). This may seem extreme .. but I remind you of the magnitude of the issues surrounding a claim of: 'exo-life discovered' !

There goes that 'chances' word again .. you are presuming an outcome which is undeterminable. The 'chance' is unknown.

yep, thats the frontiers of science for you. we are making hypothosis here, we can only really weigh chances.

Well, others seem to only be exploring the posited concept of: 'Exo-life existing, in what we presently call a 'Habitable Zone' '.

I choose to explore a less biased supposition from the outset .. and it results in a different set of priorities, which are panning out to be be a major resource allocation issue. I feel this is a more immediate crisis requiring confrontation, than exploring the niceties of a posited intellectual concept.

Why ?

demonstrate to me that you would be able to distinguish two biological lifes as being two seperate genesis.

Is that an answer .. or another question ?

if you are talking about completely diferent base life forms, the best way to do that is on earth, forget the solar system. The problem you have with an entirely different base life, is how do you look for it?

.. Goes with pursuing the posited concept that 'exo-life exists'. That question is for others to answer.

(addition added) as to why could analysis of exo planet atmosphere give strong indications of life...its because we have models that require only biology to create those indicators. Yes that could be we doont know enough, but you can apply that logic to any field of science...the standard model might be wrong, but for now we assume it is not, mainstream science at least.

A common misconception. 'Life' is already well defined. 'Exo-life' seems to be used in the sense that it is a variant of 'Life' and yet, we cannot define (or constrain) what it is, purely from the theory or known Laws of Physics or Chemistry. (As an aside: Biology on the other hand, has always been an empirical lab-based science). This characteristic, (amongst others), is actually supporting evidence that non-deterministic behaviours might be at cause the emergence of life. Such concepts are commonly accepted as 'mainstream' in the Biological Sciences. Astronomers and Cosmologists are yet to fully bridge both domains so as to achieve sufficient 'critical mass' of thinking, and depth of expertise in these concepts. Its only in the very early stages of the field's evolution and I think we're seeing the outputs of those very early stages. There's a long way to go, and much patience will be required to acquire the necessary data.

My view is that we need to take meaningful steps in acquiring that data .. over endlessly posting more and more unending hypotheticals.

Regards

[Colin Robinson]

That is already certain. There is no way we could pose a
threat to any civilization capable of communicating with us. They have been around for millions of years.

I know the argument -- another technological civilization is unlikely to be at the exact same age as ours, so it will be either much older or much younger, and it couldn't be much younger if it is able to communicate via radio, therefore it is almost certain to be much older...

But... Is it necessarily the case that a vastly older technological civilization will have vastly superior technology?

I know it's often assumed that once technological progress reaches a certain point, it will keep getting better and better, faster and faster. However, I don't see how we can be sure either that it will happen that way on Earth, or that it will have happened that way on other worlds.

Maybe there are worlds where technology advances to a certain stage, and then plateaus -- i.e. it reaches a certain level, then stays much the same for century after century, millenium after millenium?

In that case, their civilization could be vastly older than ours without being vastly more technically advanced. So maybe we could pose a threat to them after all…

[Colin Robinson]

demonstrate to me that you would be able to distinguish two biological lifes as being two seperate genesis.
if you are talking about completely diferent base life forms, the best way to do that is on earth, forget the solar system. The problem you have with an entirely different base life, is how do you look for it?

Life elsewhere in the solar system might be different enough to imply a separate beginning, without being completely different. One definition of life is, IIRC, "a chemical system capable of darwinian evolution". So how do you look for such a chemical system? Well, you can look for places in the solar system where complex chemical activity seems to be going on, and then you try to find out as much as possible about the specifics of that chemistry. You don't search only for proteins and nucleic acids, but you do look for systems of catalysts and for polymers capable of holding and passing on information...

[mutleyeng]

a chemical system capable of darwinian evolution is a pretty poor definition in my opinion. i can see quite easily other adaptive pressures on microbial life not falling ito that definition at all.
@selfism,
i underlined "known" for a reason. there is certainly speculation that there are habital zones within the solar system based on the analysis of very limited criteria. therefore you are speculating too.
i do agree with you that we have our individual choices of priorities. You have one, i have another.
So far you havnt managed to give specifics as to why yours should be the concentrated priority.
You would need to provide me with some specifics as to why exo planet atmospheric analysis in any way will be limited by laws of physics. The methodology is well known, the ability to do it already exists in some specific conditions.
The concept is not science fiction and does not require the bending of any physical laws-so far as i am aware.

your last paragraph was interesting, but i cant help feeling that is a matter for biologists within their own field

[swampyankee]

People are speculating about alternatives to water as a solvent for life, including ammonia, various hydrocarbons, liquid nitrogen, supercritical carbon dioxide, and molten salts. Each will have its own habitable zone, and some of them would probably consider life at liquid water temperatures (which span from about 273 K to about 647 K) as impossible.

[Selfsim]

@selfism,
i underlined "known" for a reason. there is certainly speculation that there are habital zones within the solar system based on the analysis of very limited criteria. therefore you are speculating too.

Nup ... I'm not using my own speculative classifications. I'm using these ones. The rankings of confirmed and unconfirmed exo-planet surface habitability is here. (They're pretty comprehensive too, given what's presently known, if you ask me).

i do agree with you that we have our individual choices of priorities. You have one, i have another.
So far you havnt managed to give specifics as to why yours should be the concentrated priority.
You would need to provide me with some specifics as to why exo planet atmospheric analysis in any way will be limited by laws of physics. The methodology is well known, the ability to do it already exists in some specific conditions.
The concept is not science fiction and does not require the bending of any physical laws-so far as i am aware.

I don't think we're on the same wavelength here ... detection of a remote exo-atmosphere is not the major issue. Concluding that exo-life exists, purely because of atmospheric composition, is. (I've tried saying this in many different ways throughout this thread ... I don't know how else to say it) ...
We can cite correlations between the two until we're blue in the face, but until we can actually confirm that certain proportions of certain exo-gases (eg: O₂) can ONLY be sustained by some critical mass of known exo-life metabolism, the presence of these gases, will only ever enable inferences of exo-life 'possibilities'. Frankly, given the diversity space of 'possible' natural exo-planetary processes, it wouldn't surprise me in the least that over time, we will discover way more O₂ renewal/sustaining processes than just earth-like life metabolism, (for instance). To me, this is such a myopic perspective, inference drawn from it about Earth-like exo-life 'possibilities', leaves me completely cold.

The physical constraints which limit the technology, appear in trying to reach exo-planets light-years away, to confirm the correlations between specific exo-gas measurements, and the presence of exo-life on the exo-body, possessing those gases. This is simply, not feasible from a practical perspective ! Our only choice from what I can see, is to try to look for exo-life locally, in order to add any credibility whatsoever, to this method.

your last paragraph was interesting, but i cant help feeling that is a matter for biologists within their own field

Chuckle, chuckle .... I passed this comment in another thread: "For some strange reason, the field of Astrobiology stands alone in science as having the sole purpose of justifying the belief that its subject matter exists !"

Regards

[Selfsim]

People are speculating about alternatives to water as a solvent for life, including ammonia, various hydrocarbons, liquid nitrogen, supercritical carbon dioxide, and molten salts. Each will have its own habitable zone, and some of them would probably consider life at liquid water temperatures (which span from about 273 K to about 647 K) as impossible.

Hi swampyankee;
See ... this is exactly what I'm on about when it comes to rampant speculation !
There is seemingly no end to the possibilities !

How does any of this speculation help in trying to pin down a practical cohesive strategy ?

I have read almost the entire history of human civilisation in this forum to explain 'the possibilities' when it comes to exo-life speculation .. and it leads to, where/what, exactly ??

Practical considerations limit the possibility space and will lead to incremental steps towards the ultimate goal.
Speculation just seems to lead to sci-fi stories, (and royalites for their authors) !

Regards

[Colin Robinson]

a chemical system capable of darwinian evolution is a pretty poor definition in my opinion. i can see quite easily other adaptive pressures on microbial life not falling ito that definition at all.

You may have a valid point there, but you haven't expressed it coherently. Would you care to rephrase?

[Colin Robinson]

The physical constraints which limit the technology, appear in trying to reach exo-planets light-years away, to confirm the correlations between specific exo-gas measurements, and the presence of exo-life on the exo-body, possessing those gases. This is simply, not feasible from a practical perspective ! Our only choice from what I can see, is to try to look for exo-life locally, in order to add any credibility whatsoever, to this method.

What do you mean by "locally"? Do mean "within this solar system"? Or "here on Earth"?

[Jeff Root]

There is no way we could pose a threat to any civilization
capable of communicating with us.
...

They have been around for millions of years.

I know the argument -- another technological civilization is
unlikely to be at the exact same age as ours, so it will be
either much older or much younger, and it couldn't be much
younger if it is able to communicate via radio, therefore it is
almost certain to be much older...

But... Is it necessarily the case that a vastly older technological
civilization will have vastly superior technology?

No, and they don't need to have vastly superior technology.

Given that they are at least several light-years away, as they
almost certainly are, no attack we could make could reach
them in less than thousands of years, and the probability of
such an attack doing significant damage on its target would
be vanishingly small, even if they raise no defense against it.
But thousands of years of lead time should be enough to
develop an adequate defense. And they'll already know
how such attacks or potential attacks had been handled
by others, anyhow.

I know it's often assumed that once technological progress
reaches a certain point, it will keep getting better and better,
faster and faster. However, I don't see how we can be sure
either that it will happen that way on Earth, or that it will
have happened that way on other worlds.

I agree with that completely. However, if they are able to
communicate with us, they will have already gained the
knowledge of many other civilizations, so they will have
plenty of ideas-- many of them well-tested-- of how to
deal with bellicose or wantonly destructive civilizations.
If they can't deal with an enemy on their own, they have
friends who will help them. That's an advantage of being
connected.

Maybe there are worlds where technology advances to a
certain stage, and then plateaus -- i.e. it reaches a certain
level, then stays much the same for century after century,
millenium after millenium?

In that case, their civilization could be vastly older than
ours without being vastly more technically advanced.
So maybe we could pose a threat to them after all…

No, we will not know they exist unless they communicate
with us. If they have the ability to communicate with us,
they will have communicated with others, and will have
gained their knowledge of how to deal with sociopaths.

-- Jeff, in Minneapolis

[mutleyeng]

You may have a valid point there, but you haven't expressed it coherently. Would you care to rephrase?

sorry, im not great at coherently.
The theory of evolution has moved on some way from origin of species. Darwinian evolution suggests adaptation for survival benefits. On an exo world the pressure may come from enviroment, like radiation- something more akin to Lamarkism perhaps

[MaDeR]

that local exploration of our Solar System has resulted in scientific and sociological benefits way beyond most human and scientific value measures. In comparison with: 'exo-atmospheric-gas-detection-and-analysis-over-light-year-distances', its returns on investment, can at least be demonstrated to be certain.

This is very, very, very wrong. By exploring exoplanets and discovering what is similiar and what is different about them, we can get to know more about our solar system and Earth itself.
If you value solar system exploration at all, then you must value exploration of everything outside it, too.

[Selfsim]

This is very, very, very wrong. By exploring exoplanets and discovering what is similiar and what is different about them, we can get to know more about our solar system and Earth itself.
If you value solar system exploration at all, then you must value exploration of everything outside it, too.

Well hello there, MaDeR ! Nice to meet you !

So I should make it clear that the point being made here pertains only to the making of progress in the exo-life discovery goal. Surveying exo-atmospheres in support of acquiring knowledge about exo-planet diversities and chemistries, is a separate issue … and one I'm happy to acknowledge has exploratory and technological benefits.

The comparison between, and subsequent prioritisation of strategies, is being made as a way of separating out the recent Astrobiological emphasis, which on its own, cannot be practically demonstrated, due to (i) a lack of capability of meaningfully interpreting measurements, once they are obtained and; (ii) I suspect, more fundamentally, because the initial premise behind Astrobiology is biased in the direction of: 'exo-life existing' in the first place. Which is Ok for launching an avenue of enquiry .. but it in doing so, it shouldn't lose track of the huge array of other possibilities and value propositions, nor should its supporters.

There are significant plans evolving which are being driven solely by Astrobiological research goals which are having impacts on local Solar System exploration projects. When this happens, one invariably compares the scientific outcomes of both approaches, in the light of exo-life detection. I am simply saying that the foreseeable scientific benefits of local exploration in the quest for learning about exo-life (if it exists), outweigh those which have a significant interpretive database lacking. The way of building that database, is by local exploration.

I don't understand why this is so difficult to get across ? It is a fairly obvious point, and I have even seen a Fraser Cain/Exo-Planetary Scientist interview, also make a similar point (although it was unintentional) … so even our media guys now understand this !!

Regards

[swampyankee]

Hi swampyankee;
See ... this is exactly what I'm on about when it comes to rampant speculation !
There is seemingly no end to the possibilities !

How does any of this speculation help in trying to pin down a practical cohesive strategy ?

I have read almost the entire history of human civilisation in this forum to explain 'the possibilities' when it comes to exo-life speculation .. and it leads to, where/what, exactly ??

Practical considerations limit the possibility space and will lead to incremental steps towards the ultimate goal.
Speculation just seems to lead to sci-fi stories, (and royalites for their authors) !

Regards

I think trying to search where we think vaguely Earth-like life (carbon based, using water as a solvent, at a temperature between about 273 and 373 K, etc) may exist is the only rational starting point. The logic for this is that we've got a better chance of recognizing this kind of life than a life-form living in the methane/ethane lakes of Titan. I'm not entirely sure that on-the-spot human explorers would recognize alien life before it literally bit them on the nose.

[Colin Robinson]

Hi swampyankee;
See ... this is exactly what I'm on about when it comes to rampant speculation !
There is seemingly no end to the possibilities !

How does any of this speculation help in trying to pin down a practical cohesive strategy ?

I have read almost the entire history of human civilisation in this forum to explain 'the possibilities' when it comes to exo-life speculation .. and it leads to, where/what, exactly ??

Let me give you one example of where "speculation" can lead to.

The 1952 Miller-Urey experiment, applied an energy source to a hydrogen-rich mixture of gases, dissolved the results in water, and demonstrated formation of compounds including amino acids.

This classic piece of lab work tested the hypothesis put forward 28 years earlier by Alexander Oparin and J.B.S. Haldane, that life on Earth could have developed from an ancient atmosphere that was hydrogen-rich, rather than oxygen-rich.

When Oparin and Haldane put forward that hypothesis, they had no way of testing it. They were speculating. And they may have been quite wrong, about the make-up of the atmosphere of ancient Earth.

But the bottom line is...

Disciplined speculation can and does stimulate history-making empirical research.