Scientists get closer to solving chemical puzzle of the origin of life - synthesis of pantetheine

[Warden_of_the_Storm]

Despite the OP?

Mainly because I take anything you say vis a vis evolution with a massive grain of salt.

 

[Ophiolite]

However, what would you say of meteor strikes and similar outside factors that introduce new variables over time?

I don't consider these to be outside factors. The introduction of significant quantities of carbon compounds, including substantial amounts of pre-biotic chemistry is, to me, a given. It was a key factor in the emergence of life (assuming pan spermia is not the explanation for Earth life and we have to look elsewhere for the origin).
I am not aware of any data that suggests the contributions from cometary or asteroidal strikes would vary qualitatively over time, so no meaningful new variables would be introduced.

The conditions and apparently interstellar ingredients on Earth remain dynamic to this day. I

Yes, terrestrial conditions are dynamic, but as noted above, I see no evidence for significant variability in "interstellar ingredients". If you have such evidence I would like to see it.

You need also keep in the forefront of your mind that, no matter how long it takes for life to emerge, once it does so that ends the game. No more new life. The first life just uses the chemicals tas food that might otherwise have had the potential to lead to further life.

After that first life emerges it's just 3.5 billion years of evolution until the universe produces entities capable of thinking the Earth is flat.
I think the next 3.5 billion years will likely see some small improvements.

If perhaps less so today than when pantetheine first formed.

And today it couldn't form - without the help of entities that don't think the Earth is flat. You see - we're allready getting progress!

 

[SelfSim]

.. You need also keep in the forefront of your mind that, no matter how long it takes for life to emerge, once it does so that ends the game. No more new life. The first life just uses the chemicals tas food that might otherwise have had the potential to lead to further life.

The synthesis of precursor molecules, I think, is fairly easy to visualise and understand in the bulk-reactions-over-deep-time model.

The process which leads to the emerge of an in-common, high fidelity, self-replicating templated sequence, (or code), however, is far from being simple for us to understand.

 

[Niels]

I don't consider these to be outside factors. The introduction of significant quantities of carbon compounds, including substantial amounts of pre-biotic chemistry is, to me, a given. It was a key factor in the emergence of life (assuming pan spermia is not the explanation for Earth life and we have to look elsewhere for the origin).
I am not aware of any data that suggests the contributions from cometary or asteroidal strikes would vary qualitatively over time, so no meaningful new variables would be introduced.

I wonder about our relatively 'dead' neighbor planets that turned out so differently. Saying that we're in a 'Goldilocks zone' seems convenient after the fact, so I'm not suggesting that here, but different factors were clearly at play. Mars was apparently the most Earth-like at one point, replete with oceans, yet from what we've gathered life didn't develop there as it did on Earth.

The diverse chemical compositions of our neighboring planets suggests to me a highly dynamic origin. Pan spermia makes for good science fiction, but I'm not suggesting that here. Rather, a diverse set of conditions and different factors leading to different outcomes. Some of which may have been from outside of our Solar system. Oumuamua came pretty close. I would have liked to learn more about it.

Yes, terrestrial conditions are dynamic, but as noted above, I see no evidence for significant variability in "interstellar ingredients". If you have such evidence I would like to see it.

You need also keep in the forefront of your mind that, no matter how long it takes for life to emerge, once it does so that ends the game. No more new life. The first life just uses the chemicals tas food that might otherwise have had the potential to lead to further life.

After that first life emerges it's just 3.5 billion years of evolution until the universe produces entities capable of thinking the Earth is flat.
I think the next 3.5 billion years will likely see some small improvements.

And today it couldn't form - without the help of entities that don't think the Earth is flat. You see - we're allready getting progress!

We've found compounds and metals in meteorites that don't occur naturally here. One example of the former being King Tut's dagger. It has long been theorized that the basic building blocks of life either got here from elsewhere or were somehow initiated by the force of impact or other such conditions. Which may not have been necessary for pantheneine.

As far as new life goes, it does seem to me that life should arrise under certain conditions regardless of location. When life arose on Earth, was it the first life in the universe? Although pan spermia is one possibility, I think it's more likely that life can simply appear independently in multiple locations.

On the topic of Flat Earthers. Even in antiquity, there is evidence that many people knew the Earth was round. Others thought it was curved like the back of a turtle. At least that's closer to what we can observe than a flat planet. Flat-earther may have even been an insult then much like it is today. At least among those would have known better. Ships wouldn't be able to navigate large bodies of water, for instance, if the Earth was flat. I doubt many sailors believed that "There be Dragons" at the edge of the map. They just hadn't explored everywhere yet and it was a fanciful way to deal with that. Even the idea of Christopher Columbus set out to prove that the Earth was round can be considered a tall tale. Columbus, his sponsors, and probably most of his contemporaries knew it was round. They just underestimated its size and unexpectedly encountered other lands between Spain and India.

For what it's worth, if you mentioned that last bit as a dig because I'm a Christian on a Christian website... modern science, and even the Enlightenment, can be seen as an outgrowth of Christian thought. Not to diminish the influence of Greek philosophers, Eastern thought or other contributors, but science as we know it has always had a strong Christian presence. As long as we stick to the evidence and don't try to push political agendas under the name of science, you won't find me disagreeing much about data and whatnot. The way I see things is God did it however he did it. This isn't exactly a rare position hold, despite some of what you may read on this site (FWIW, Flat Earthers look like a psyop to me as I've never even met one). I'm not a big fan of "god of the gaps" arguments either. Rather, seeing everything as evidence for a creator. But I didn't post in this thread to proselytize. For that, I would encourage you to read (or become re-aquainted with) the gospel, but everything else I've posted here is simply engaging the subject matter. Maybe delving into the realm of speculative hard science fiction a little as I do enjoy the genre and it probably shows, but I like to keep the science part as accurate as possible when doing so.

This is just a cool article. One of the more interesting things I've read today.

 

[AV1611VET]

Mainly because I take anything you say vis a vis evolution with a massive grain of salt.

I've been saying for years that the Antichrist is going to make evolution so simple a child can understand it.

So you can imagine how I felt when I read this in the OP:

The pathway, which has evaded scientists for decades, involved relatively simple molecules probably present on early Earth that combined at room temperature over months.

 

[Warden_of_the_Storm]

I've been saying for years that the Antichrist is going to make evolution so simple a child can understand it.

So you can imagine how I felt when I read this in the OP:

The pathway, which has evaded scientists for decades, involved relatively simple molecules probably present on early Earth that combined at room temperature over months.

Yeah, we know you've been saying that.

And I do what I always do: take anything you say vis a vis evolution with a massive grain of salt.

 

[SelfSim]

.. You need also keep in the forefront of your mind that, no matter how long it takes for life to emerge, once it does so that ends the game. No more new life.

... As far as new life goes, it does seem to me that life should arrise under certain conditions regardless of location.

I've always seen the above two very common statements as being somewhat in tension with eachother when considering what we observe from Earth's neighbouring bodies, (ie: the Moon, Venus and Mars, etc). There is no immediately remotely observable, (macroscopic), life on any of these bodies, yet Earth obviously has easily remotely observable life and life is, (hopefully for some), expected to be found at least on Venus or Mars.

So:
i) The first statement above whilst, (as presented), is about the subsequent emergence of 'new' life, (whatever that means), also implies that once life starts, it will continue to persist (presumably via adaption and metabolic mechanisms).

ii) The second statement implies the inevitable deterministic resultant of life emergence, once certain conditions are conducive to that emergence.

iii) Yet there is no immediately remotely observable, (macroscopic), life on the locally observable astronomical bodies, when we would quite reasonably expect to see something. There are lots of possible hypotheses for explaining this, and I'm not trying to initiate debate on those hypotheses, rather, I am pointing out that the two statements are not intuitively obvious statements at face value, nor do they sit comfortably side-by-side with eachother.

I conclude that both statements require a lot more support from bodies other than earth, before either can be taken as being an inevitable 'given', precisely because of the available observational evidence currently available (scant as it is). Extrapolation from our singular example of Earth-life is inadequate .. even though 'its all we got to go on'.

 

[AV1611VET]

Yeah, we know you've been saying that.

And I do what I always do: take anything you say vis a vis evolution with a massive grain of salt.

In this case you messed up, didn't you?

 

[Astrid]

I wonder about our relatively 'dead' neighbor planets that turned out so differently. Saying that we're in a 'Goldilocks zone' seems convenient after the fact, so I'm not suggesting that here, but different factors were clearly at play. Mars was apparently the most Earth-like at one point, replete with oceans, yet from what we've gathered life didn't develop there as it did on Earth.

The diverse chemical compositions of our neighboring planets suggests to me a highly dynamic origin. Pan spermia makes for good science fiction, but I'm not suggesting that here. Rather, a diverse set of conditions and different factors leading to different outcomes. Some of which may have been from outside of our Solar system. Oumuamua came pretty close. I would have liked to learn more about it.



We've found compounds and metals in meteorites that don't occur naturally here. One example of the former being King Tut's dagger. It has long been theorized that the basic building blocks of life either got here from elsewhere or were somehow initiated by the force of impact or other such conditions. Which may not have been necessary for pantheneine.

As far as new life goes, it does seem to me that life should arrise under certain conditions regardless of location. When life arose on Earth, was it the first life in the universe? Although pan spermia is one possibility, I think it's more likely that life can simply appear independently in multiple locations.

On the topic of Flat Earthers. Even in antiquity, there is evidence that many people knew the Earth was round. Others thought it was curved like the back of a turtle. At least that's closer to what we can observe than a flat planet. Flat-earther may have even been an insult then much like it is today. At least among those would have known better. Ships wouldn't be able to navigate large bodies of water, for instance, if the Earth was flat. I doubt many sailors believed that "There be Dragons" at the edge of the map. They just hadn't explored everywhere yet and it was a fanciful way to deal with that. Even the idea of Christopher Columbus set out to prove that the Earth was round can be considered a tall tale. Columbus, his sponsors, and probably most of his contemporaries knew it was round. They just underestimated its size and unexpectedly encountered other lands between Spain and India.

For what it's worth, if you mentioned that last bit as a dig because I'm a Christian on a Christian website... modern science, and even the Enlightenment, can be seen as an outgrowth of Christian thought. Not to diminish the influence of Greek philosophers, Eastern thought or other contributors, but science as we know it has always had a strong Christian presence. As long as we stick to the evidence and don't try to push political agendas under the name of science, you won't find me disagreeing much about data and whatnot. The way I see things is God did it however he did it. This isn't exactly a rare position hold, despite some of what you may read on this site (FWIW, Flat Earthers look like a psyop to me as I've never even met one). I'm not a big fan of "god of the gaps" arguments either. Rather, seeing everything as evidence for a creator. But I didn't post in this thread to proselytize. For that, I would encourage you to read (or become re-aquainted with) the gospel, but everything else I've posted here is simply engaging the subject matter. Maybe delving into the realm of speculative hard science fiction a little as I do enjoy the genre and it probably shows, but I like to keep the science part as accurate as possible when doing so.

This is just a cool article. One of the more interesting things I've read today.

Its not just antiquity.
Our Filipina maid thought the world is flat.

Kind of- she said- made her dizzy when she
realized that its really round, like an orange.

It took some explaining, but she got it.

 

[AV1611VET]

Our Filipina maid thought the world is flat.

So what?

You thought Pluto was our ninth planet, didn't you?

Kind of- she said- made her dizzy when she realized that its really round, like an orange.

It took some explaining, but she got it.

Was Pluto explained to you too?

And, if so, did you get it?

 

[BCP1928]

So what?

You thought Pluto was our ninth planet, didn't you?

The shape of the Earth is an objective fact. The status of Pluto as a planet is merely the result of a man-made classification scheme.

 

[Ophiolite]

I wonder about our relatively 'dead' neighbor planets that turned out so differently. Saying that we're in a 'Goldilocks zone' seems convenient after the fact, so I'm not suggesting that here, but different factors were clearly at play. Mars was apparently the most Earth-like at one point, replete with oceans, yet from what we've gathered life didn't develop there as it did on Earth.

We have highly plausible explanations for why Venus and Mars turned out differently. Venus - too close to the sun experienced runaway greenhouse effect. Mars - too lightweight loses magnetic field as core cools and thus atmosphere stripped by solar wind.

I have no reason to assert that, while Mars was a viable home to life (say for a billion years or so), that life did not parallel what occurred on Earth. Do you have a reason to so assert?
I am among that small group of nutters who suspect that the Viking Lander experiments did discover Martian life. (Not conspiracy theory - just a more cautious approach to the data.)

As far as new life goes, it does seem to me that life should arrise under certain conditions regardless of location. When life arose on Earth, was it the first life in the universe? Although pan spermia is one possibility, I think it's more likely that life can simply appear independently in multiple locations

I don't favour reaching conclusions on the basis of one data point.

For what it's worth, if you mentioned that last bit as a dig because I'm a Christian on a Christian website... modern science, and even the Enlightenment, can be seen as an outgrowth of Christian thought.

Nothing was further from my mind. I am familiar with the early awareness of the roundness of the Earth amongst informed humans. I was simply reflecting on the sad disparity between the two ends of the human spectrum when it comes to critical thinking. A species that can simultaneously land members of that species on another world, while denying that it ever happened - ironic!
To put it another way, flat-Earthers are simply misguided fools whose beliefs have nothing whatsoever to do with Christianity.

The diverse chemical compositions of our neighboring planets suggests to me a highly dynamic origin.

I don't follow what you are saying here. Are the compositions of the terrestrial planets identical? No, certainly not. But they are broadly similar. As an example, what is the "go to" lava composition on each of them? Basalt. Are there variations in the composition of the basalts? Certainly, but only as might be expected from a combination of location in the solar nebula and chance.
And "highly dynamic"? I suppose that is as good a way as any as of describing the assembly of planetesimals and planets via collision. But you seem to wish to imply this somehow produced something radically different. If so what? Either I have wholly missed your point, or your point is wrong. I look forward to clarification.

We've found compounds and metals in meteorites that don't occur naturally here. One example of the former being King Tut's dagger. It has long been theorized that the basic building blocks of life either got here from elsewhere or were somehow initiated by the force of impact or other such conditions. Which may not have been necessary for pantheneine.

Can you be more specific as to what you mean by compounds that don't occur naturally here? There is nothing abnormal about King Tut's dagger. There are no metals present in it that are not present in the Earth. If we could obtain a sample of the Earths' core we would likely find a close match to the proportions of Fe, Ni and trace elements found in it. That would be as expected based upon our understanding of planetary formation.

Yes, the origin of basic pre-biotic chemicals is as you suggested, but I don't understand what conclusion you are drawing from it. And as to pantheneine, surely the experiment this thread is about established it as unlikely that pantheneine originated extraterrestrially, or as a consequence of impact processes.

I am taking an adversarial position on your post because I think that your thoughts on the subject are either wooly, wrong, or irrelvant. I am quite happy to be shown to be mistaken via some concisely stated evidence and argument.

 

[SelfSim]

Can you be more specific as to what you mean by compounds that don't occur naturally here? There is nothing abnormal about King Tut's dagger. There are no metals present in it that are not present in the Earth. If we could obtain a sample of the Earths' core we would likely find a close match to the proportions of Fe, Ni and trace elements found in it. That would be as expected based upon our understanding of planetary formation.

Hmmm .. all fair enough. However from: 'The meteoritic origin of Tutankhamun's iron dagger blade', Comelli etal, May 2016:

The blade's high Ni content, along with the minor amount of Co and a Ni/Co ratio of ~20, strongly suggests an extraterrestrial origin.

1. The Ni content in the bulk metal of most iron meteorites ranges from 5 wt% to 35 wt%, whereas it never exceeds 4 wt% in historical iron artifacts from terrestrial ores produced before the 19th C 1992).

They provide the following graph as further support via comparisons with other meteorites:

I am taking an adversarial position on your post because I think that your thoughts on the subject are either wooly, wrong, or irrelvant. I am quite happy to be shown to be mistaken via some concisely stated evidence and argument.

See above for one that's not particularly 'wrong'.

PS: Also: from Wiki on Extraterrestrial materials (Astrobiology):

The abundant organic compounds in primitive meteorites and interplanetary dust particles are thought to originate largely in the interstellar medium. However, this material may have been modified in the protoplanetary disk and has been modified to varying extents in the asteroidal parent bodies.[30]

Cosmic dust contains complex organic compounds (amorphous organic solids with a mixed aromatic-aliphatic structure) that can be created naturally by stars and radiation.[31][32][33] These compounds, in the presence of water and other habitable factors, are thought to have produced and spontaneously assembled the building blocks of life.[34][35]

 

[Ophiolite]

Hmmm .. all fair enough. However from: 'The meteoritic origin of Tutankhamun's iron dagger blade', Comelli etal, May 2016:

Please clarify. The information you presented confirmed my point: King Tut's dagger is almost certainly made of meteoritic iron. My related statements, implicit and explicit, stand - there are no metals compounds in it that are not found on Earth; the only difference between its Ni:Fe ratio and that of the iron we observe on Earth is that on Earth we have no access to iron from the core, whereas meteoritic iron formed in planetoids large enough and old enough to have developed a differentiated core and mantle, a process that alters the Ni:Fe ratio. Thus @Miles 's statement that "We've found compounds and metals in meteorites that don't occur naturally here." is contradicted in the case of King Tut's dagger. so, I asked for examples that would support his erroneous statement.

Again, I find nothing in the least controversial about the observations you have added on interstellar organics and their subsequent modification. (I especially liked the experiment of impacting amino acid laden ice at bolide velocities where it was found that numerous polypeptides were formed in the collision.) What I was questioning was what conclusion @Miles intended to derive from these comments.

 

[Astrid]

I wonder about our relatively 'dead' neighbor planets that turned out so differently. Saying that we're in a 'Goldilocks zone' seems convenient after the fact, so I'm not suggesting that here, but different factors were clearly at play. Mars was apparently the most Earth-like at one point, replete with oceans, yet from what we've gathered life didn't develop there as it did on Earth.

The diverse chemical compositions of our neighboring planets suggests to me a highly dynamic origin. Pan spermia makes for good science fiction, but I'm not suggesting that here. Rather, a diverse set of conditions and different factors leading to different outcomes. Some of which may have been from outside of our Solar system. Oumuamua came pretty close. I would have liked to learn more about it.



We've found compounds and metals in meteorites that don't occur naturally here. One example of the former being King Tut's dagger. It has long been theorized that the basic building blocks of life either got here from elsewhere or were somehow initiated by the force of impact or other such conditions. Which may not have been necessary for pantheneine.

As far as new life goes, it does seem to me that life should arrise under certain conditions regardless of location. When life arose on Earth, was it the first life in the universe? Although pan spermia is one possibility, I think it's more likely that life can simply appear independently in multiple locations.

On the topic of Flat Earthers. Even in antiquity, there is evidence that many people knew the Earth was round. Others thought it was curved like the back of a turtle. At least that's closer to what we can observe than a flat planet. Flat-earther may have even been an insult then much like it is today. At least among those would have known better. Ships wouldn't be able to navigate large bodies of water, for instance, if the Earth was flat. I doubt many sailors believed that "There be Dragons" at the edge of the map. They just hadn't explored everywhere yet and it was a fanciful way to deal with that. Even the idea of Christopher Columbus set out to prove that the Earth was round can be considered a tall tale. Columbus, his sponsors, and probably most of his contemporaries knew it was round. They just underestimated its size and unexpectedly encountered other lands between Spain and India.

For what it's worth, if you mentioned that last bit as a dig because I'm a Christian on a Christian website... modern science, and even the Enlightenment, can be seen as an outgrowth of Christian thought. Not to diminish the influence of Greek philosophers, Eastern thought or other contributors, but science as we know it has always had a strong Christian presence. As long as we stick to the evidence and don't try to push political agendas under the name of science, you won't find me disagreeing much about data and whatnot. The way I see things is God did it however he did it. This isn't exactly a rare position hold, despite some of what you may read on this site (FWIW, Flat Earthers look like a psyop to me as I've never even met one). I'm not a big fan of "god of the gaps" arguments either. Rather, seeing everything as evidence for a creator. But I didn't post in this thread to proselytize. For that, I would encourage you to read (or become re-aquainted with) the gospel, but everything else I've posted here is simply engaging the subject matter. Maybe delving into the realm of speculative hard science fiction a little as I do enjoy the genre and it probably shows, but I like to keep the science part as accurate as possible when doing so.

This is just a cool article. One of the more interesting things I've read today.

A couple of observations-
We are taught that Columbus was
on a Quest for China, with a grossly
miscalculated notion of distance.
The "round v flat" thing is a myth,
Sort of like G.W. throwing dollar across
Potomic river.

As for Christian thought- whatever that
is- theres some amusing irony in that,
but considering the pervasive grip of Christianity,
one might say that everything in Europe
developed from " Christian thought".

Much of it, as so clearly evident in these
pages, deeply antithetical to science.

 

[Niels]

We have highly plausible explanations for why Venus and Mars turned out differently. Venus - too close to the sun experienced runaway greenhouse effect. Mars - too lightweight loses magnetic field as core cools and thus atmosphere stripped by solar wind.

I have no reason to assert that, while Mars was a viable home to life (say for a billion years or so), that life did not parallel what occurred on Earth. Do you have a reason to so assert?
I am among that small group of nutters who suspect that the Viking Lander experiments did discover Martian life. (Not conspiracy theory - just a more cautious approach to the data.)

Much like you, I'd like to think that there was life on Mars. However, I haven't seen any evidence that there was. Until I have access to evidence that there was, or maybe still is, I will continue to conclude that there isn't. If you can provide compelling evidence that the Viking Lander discovered Martian life, I'd like to see it.

I don't favour reaching conclusions on the basis of one data point.

Fair enough. I feel similarly about the idea that all possible reactions have necessarily already occurred here on Earth. It can be considered one data point.

Nothing was further from my mind. I am familiar with the early awareness of the roundness of the Earth amongst informed humans. I was simply reflecting on the sad disparity between the two ends of the human spectrum when it comes to critical thinking. A species that can simultaneously land members of that species on another world, while denying that it ever happened - ironic!
To put it another way, flat-Earthers are simply misguided fools whose beliefs have nothing whatsoever to do with Christianity.

Thanks for the clarification. I do hope they are simply misguided, as you say, and not a psyop.

I don't follow what you are saying here. Are the compositions of the terrestrial planets identical? No, certainly not. But they are broadly similar. As an example, what is the "go to" lava composition on each of them? Basalt. Are there variations in the composition of the basalts? Certainly, but only as might be expected from a combination of location in the solar nebula and chance.
And "highly dynamic"? I suppose that is as good a way as any as of describing the assembly of planetesimals and planets via collision. But you seem to wish to imply this somehow produced something radically different. If so what? Either I have wholly missed your point, or your point is wrong. I look forward to clarification.

Although we do share a lot with our neighboring planets, their environments are better suited to different kinds of reactions. That's why the atmosphere on Venus, for instance, is different than the atmosphere on Saturn. Some elements can only be briefly sustained under artificial conditions in a lab on Earth, but I think it's reasonable to conclude that such conditions might occur naturally elsewhere. Which isn't to say that they might occur somewhere deep within the Earth or elsewhere on this planet that we're simply unaware of. Rather, that different conditions are more suitable for different reactions.

Can you be more specific as to what you mean by compounds that don't occur naturally here? There is nothing abnormal about King Tut's dagger. There are no metals present in it that are not present in the Earth. If we could obtain a sample of the Earths' core we would likely find a close match to the proportions of Fe, Ni and trace elements found in it. That would be as expected based upon our understanding of planetary formation.

I mentioned King Tut's dagger as an example of an alloy that wasn't produced by humans. Hence, why I said it was an example of the former. Reading your previous reply, I should have been more clear. The intention wasn't to suggest that iron doesn't occur naturally here. That said, looking back at what I wrote, I should also clarify that I view extraplanetary objects like asteroids and meteor impacts as natural occurrences. Just not something that would happen if Earth was left alone for a while without being struck by objects that didn't originate here. My mention of Oumuamua was more speculative.

Yes, the origin of basic pre-biotic chemicals is as you suggested, but I don't understand what conclusion you are drawing from it. And as to pantheneine, surely the experiment this thread is about established it as unlikely that pantheneine originated extraterrestrially, or as a consequence of impact processes.

I agree. That's one of the main takeaways I got from the article. I'm not suggesting that pantheneine is necessarily a consequence of extraplanetary impacts. Rather, I think it's presumtuous to conclude that all reactions have already occurred on Earth, or necessarily would within a specified time frame.

I am taking an adversarial position on your post because I think that your thoughts on the subject are either wooly, wrong, or irrelvant. I am quite happy to be shown to be mistaken via some concisely stated evidence and argument.

Fair enough. That's often par the course when discussing nuanced topics on a message board. Much of the context is either missing or assumed. The human mind is great at filling in the blanks, whether rightly or wrongly. We can't realistically expect a book's worth of content within a few brief paragraphs. More time and energy would need to be spent explaining what we do and don't mean, how we arrived at our conclusions, citing other publications, etc. However, that inherent degree of 'wooliness' shouldn't stop us from discussing these things.

 

[Astrid]

Much like you, I'd like to think that there was life on Mars. However, I haven't seen any evidence that there was. Until I have access to evidence that there was, or maybe still is, I will continue to conclude that there isn't. If you can provide compelling evidence that the Viking Lander discovered Martian life, I'd like to see it.



Fair enough. I feel similarly about the idea that all possible reactions have necessarily already occurred here on Earth. It can be considered one data point.


Thanks for the clarification. I do hope they are simply misguided, as you say, and not a psyop.



Although we do share a lot with our neighboring planets, their environments are better suited to different kinds of reactions. That's why the atmosphere on Venus, for instance, is different than the atmosphere on Saturn. Some elements can only be briefly sustained under artificial conditions in a lab on Earth, but I think it's reasonable to conclude that such conditions might occur naturally elsewhere. Which isn't to say that they might occur somewhere deep within the Earth or elsewhere on this planet that we're simply unaware of. Rather, that different conditions are more suitable for different reactions.


I mentioned King Tut's dagger as an example of an alloy that wasn't produced by humans. Hence, why I said it was an example of the former. Reading your previous reply, I should have been more clear. The intention wasn't to suggest that iron doesn't occur naturally here. That said, looking back at what I wrote, I should also clarify that I view extraplanetary objects like asteroids and meteor impacts as natural occurrences. Just not something that would happen if Earth was left alone for a while without being struck by objects that didn't originate here. My mention of Oumuamua was more speculative.


I agree. That's one of the main takeaways I got from the article. I'm not suggesting that pantheneine is necessarily a consequence of extraplanetary impacts. Rather, I think it's presumtuous to conclude that all reactions have already occurred on Earth, or necessarily would within a specified time frame.


Fair enough. That's often par the course when discussing nuanced topics on a message board. Much of the context is either missing or assumed. The human mind is great at filling in the blanks, whether rightly or wrongly. We can't realistically expect a book's worth of content within a few brief paragraphs. More time and energy would need to be spent explaining what we do and don't mean, how we arrived at our conclusions, citing other publications, etc. However, that inherent degree of 'wooliness' shouldn't stop us from discussing these things.

Different enviorns- wise, there are very few impact
craters on Venus. That is profoudly related to
any possibility for life to develop.

On "all possible reactions" i presupposed thats
taken as " within those parameters". Which
certainly were many and various.


Life on Mars..phrases like " what Ive seen" or
"not compelling" are kind of irrelevant.
There is sketchy / ambiguous evidence.

Its "wait and see", unlike w Venus, where its " no chance".

 

[SelfSim]

Please clarify. The information you presented confirmed my point: King Tut's dagger is almost certainly made of meteoritic iron. My related statements, implicit and explicit, stand - there are no metals compounds in it that are not found on Earth; the only difference between its Ni:Fe ratio and that of the iron we observe on Earth is that on Earth we have no access to iron from the core, whereas meteoritic iron formed in planetoids large enough and old enough to have developed a differentiated core and mantle, a process that alters the Ni:Fe ratio. Thus @Miles 's statement that "We've found compounds and metals in meteorites that don't occur naturally here." is contradicted in the case of King Tut's dagger. so, I asked for examples that would support his erroneous statement.

I'm just tracking (and fact checking) the debate you're having with @Miles in this thread .. its a good one thus far (thank you for both of your contributions to it) and I'm interested in the topic. (IOW: I'm not really directly challenging what you've said. I note that your idea about a match between meteoric iron and a hypothetical sample from Earth's core is a solid one, which is well supported by planetary formation thinking.

Again, I find nothing in the least controversial about the observations you have added on interstellar organics and their subsequent modification. (I especially liked the experiment of impacting amino acid laden ice at bolide velocities where it was found that numerous polypeptides were formed in the collision.) What I was questioning was what conclusion @Miles intended to derive from these comments.

Sure .. all good. Feel free to use any supporting info I might post to make any points which might come up.
At the moment, I'm mainly just posting materials for anyone else who's interested .. Its a good learning thread (apart from some of the other distractions).

 

[SelfSim]

Its "wait and see", unlike w Venus, where its " no chance".

Aside: I wish another debating opponent I have on another board, (for more than 10 years,now!) would come a little closer to that viewpoint.

My point being that the 'no chance' viewpoint is definitely not a universally accepted one, (although I'm also close to that viewpoint).

 

[SelfSim]

Much like you, I'd like to think that there was life on Mars. However, I haven't seen any evidence that there was. Until I have access to evidence that there was, or maybe still is, I will continue to conclude that there isn't. If you can provide compelling evidence that the Viking Lander discovered Martian life, I'd like to see it.

An aside: Thank your for contributions thus far in this debate .. I find the topic interesting and a good learning opportunity.

I couldn't resist commenting on the Mars research you mention above. I'm waiting for images of a big tongue licking the rover cameras on Mars but I think the most important find from the data collected, thus far, is the verification of relatively complex organics, (ie: getting upwards in molecular weight but certainly not up to bio-organic range).

If no such high molecular weight evidence is produced before the end of my life, I'd still be excited because such an absence under tightly controlled experimental test conditions, permits an inference and question of: 'likely, no life past or present, on Mars .. but why?', which is something the present-day optimist martian Astrobiologists show few signs of being capable of visualising.