Author Topic: The Labeled Release experiment on the Viking mission  (Read 25168 times)

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #20 on: 01/07/2020 02:58 am »
Why We May Have Already Found Life On Mars with Dr Patricia Ann Straat:



Oh dear.  Still pushing the same barrow after so many decades of failure.  It's sad really.

Regardless of people's take there were only 8 runs of the Viking biology experiments in total.  That is an incredibly limited data set.

We now know that all the experiments were conceptually flawed in their assumptions.
Apologies in advance for any lack of civility - it's unintended

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #21 on: 01/07/2020 03:16 am »
Quote
Ghost-like moving lights, resembling will-Oí-the-wisps on Earth that are formed by spontaneous ignition of methane, have been video-recorded on the Martian surface

Just read this from George's article.
Anyone know which paper or video this is from? (if it exists)

It's a really dodgy claim, stated without evidence (Nomadd's link does not contain i)t.  1) No video has been obtained from Mars. 2) How can methane spontaneously combust in an atmosphere essentially without oxygen. 3) It's a claim made in a scientific american story, a popular magazine, not a peer reviewed journal.
Apologies in advance for any lack of civility - it's unintended

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #22 on: 01/07/2020 07:05 am »
Why We May Have Already Found Life On Mars with Dr Patricia Ann Straat:



Oh dear.  Still pushing the same barrow after so many decades of failure.  It's sad really.

Regardless of people's take there were only 8 runs of the Viking biology experiments in total.  That is an incredibly limited data set.

We now know that all the experiments were conceptually flawed in their assumptions.

No we don’t all know they were conceptually flawed in their assumptions. Care to provide some evidence of that claim, otherwise it just looks like you’re just trying to pass off your personal opinion as an actual fact.

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #23 on: 01/07/2020 07:06 am »
Quote
Ghost-like moving lights, resembling will-Oí-the-wisps on Earth that are formed by spontaneous ignition of methane, have been video-recorded on the Martian surface

Just read this from George's article.
Anyone know which paper or video this is from? (if it exists)

It's a really dodgy claim, stated without evidence (Nomadd's link does not contain i)t.  1) No video has been obtained from Mars. 2) How can methane spontaneously combust in an atmosphere essentially without oxygen. 3) It's a claim made in a scientific american story, a popular magazine, not a peer reviewed journal.

And now again youíre just trying to pass off a personal opinion as a fact.

Offline hop

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Re: The Labeled Release experiment on the Viking mission
« Reply #24 on: 01/07/2020 05:41 pm »
And now again youíre just trying to pass off a personal opinion as a fact.
Um, no. Dalhousie's post was indeed supported by well established facts:
Quote from: Dalhousie
1) No video has been obtained from Mars.
This is a fact, unless you count timelapse, which wouldn't be likely to definitively show the claimed phenomena. MSL is theoretically capable of low frame rate video, but that capability has not be used in any significant way on the surface. Certainly not for atmospheric monitoring. AFAIK no previous mission was capable of frame rates we'd call video at all, except maybe the Phoenix MARDI, which was never used due to fears of triggering a spacecraft fault.
Quote from: Dalhousie
2) How can methane spontaneously combust in an atmosphere essentially without oxygen.
It's a fact that methane combustion requires an oxidizer, and oxidizers are in short supply in the martian atmosphere.
Quote from: Dalhousie
3) It's a claim made in a scientific american story, a popular magazine, not a peer reviewed journal.
Scientific American is, in fact, a popular magazine and not a peer reviewed journal. Moreover, the page containing the claim was a blog post, which frequently have a lower standard of fact checking than articles.

This isn't just elitist nitpicking: A scientific article would cite the sources for the various claims, allowing the reader to find and evaluate the underlying research. The blog post does not.

I would add that the claim is nonsensical in another way: Even if the supposed phenomena has been observed, it's extremely unlikely any of the instrument suites landed on Mars could definitively attribute it to methane. Certainly timelapse video alone would not support such a definitive conclusion.
« Last Edit: 01/08/2020 05:54 pm by hop »

Offline Star One

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The Labeled Release experiment on the Viking mission
« Reply #25 on: 01/08/2020 07:39 am »
And now again youíre just trying to pass off a personal opinion as a fact.
Um, no. Dalhousie's post was indeed supported by well established facts:
Quote from: Dalhousie
1) No video has been obtained from Mars.
This is a fact, unless you count timelapse, which wouldn't be likely to definitively show the claimed phenomena. MSL is theoretically capable of low frame rate video, but that capability has not be used in any significant way on the surface. Certainly not for atmospheric monitoring. AFAIK no previous mission was capable of frame rates we'd call video at all, except maybe the Phoenix MARDI, which was never used due to fears of triggering a spacecraft fault.
Quote from: Dalhousie
2) How can methane spontaneously combust in an atmosphere essentially without oxygen.
It's a fact that methane combustion requires an oxidizer, and oxidizers are are in short supply in the martian atmosphere.
Quote from: Dalhousie
3) It's a claim made in a scientific american story, a popular magazine, not a peer reviewed journal.
Scientific American is, in fact, a popular magazine and not a peer reviewed journal. Moreover, the page containing the claim was a blog post, which frequently have a lower standard of fact checking than articles.

This isn't just elitist nitpicking: A scientific article would cite the sources for the various claims, allowing the reader to find and evaluate the underlying research. The blog post does not.

I would add that the claim is nonsensical in another way: Even if the supposed phenomena has been observed, it's extremely unlikely any of the instrument suites landed on Mars could definitively attribute it to methane. Certainly timelapse video alone would not support such a definitive conclusion.

This matter could easily be resolved if NASA repeated these or similar experiments on another mission, but hasnít so I regard the matter as still open.

Also if someone doesnít want something to look as if itís more than just a personal opinion maybe they should have fully supported their statements more, rather than relying on another poster to do this work for them.
« Last Edit: 01/08/2020 07:48 am by Star One »

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #26 on: 01/09/2020 12:20 am »
Also if someone doesnít want something to look as if itís more than just a personal opinion maybe they should have fully supported their statements more, rather than relying on another poster to do this work for them.

I would have thought on this forum the facts that there was no video from Mars and that is not enough oxygen in the atmosphere to support combustion were sufficiently well known  to not need elaboration.

The fact that Scientific American is a popular magazine not a science journal should be obvious from the content and the front matter.

Quote
This matter could easily be resolved if NASA repeated these or similar experiments on another mission, but hasnít so I regard the matter as still open.

Why has it taken so long is explained by two things.  Firstly, the  20 year hiatus in lander missions on Mars. 


Secondly, there is no point repeating  experiments that were known to be flawed and gave obvious results.  You need to do different experiments.  Specifically testing the primary hypothesis from Viking that the results were from reactive soil chemistry.   All the Mars surface missions since then except Schiaparelli have addressed this question in some way.


To test this hypothesis this you need to get a better handle on soil physics, chemistry, mineralogy, texture, and reactivity.  This has been done:  physics - all missions to some degree; chemistry - Pathfinder, Spirit, Opportunity, Curiosity; mineralogy -  Spirit, Opportunity, Curiosity (plus lesser capabilities on  Pathfinder, Phoenix); texture -  Curiosity, Phoenix (plus lesser capabilities on Spirit, Opportunity); reactivity - Phoenix. ExoMars, the 2020 NASA rover and the Chinese mission will add to all of these except reactivity,  assuming they are successful of course.

We also need to explore the issue of organic carbon.  This has been done by Phoenix and Curiosity.  We now know it is there.   The 2020 rover and the ExoMars mission will, all being well add to our knowledge in these areas.

We now know that perchlorate explains both the soil reactivity, and the low organic content of the soils.  We know that the surface of Mars is largely uninhabitable by life as we know it and  as we can reasonably imagine.  There may be special regions, but these are relatively rare.

We now are at a position to have another crack at the question, using new techniques in the possible special regions.  But as with Viking it would be a very expensive mission (full cleanliness an sterilisation and the results will probably be ambiguous.  It would need multiple missions  to test  the results.
Apologies in advance for any lack of civility - it's unintended

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #27 on: 01/10/2020 03:55 pm »
Also if someone doesn’t want something to look as if it’s more than just a personal opinion maybe they should have fully supported their statements more, rather than relying on another poster to do this work for them.

I would have thought on this forum the facts that there was no video from Mars and that is not enough oxygen in the atmosphere to support combustion were sufficiently well known  to not need elaboration.

The fact that Scientific American is a popular magazine not a science journal should be obvious from the content and the front matter.

Quote
This matter could easily be resolved if NASA repeated these or similar experiments on another mission, but hasn’t so I regard the matter as still open.

Why has it taken so long is explained by two things.  Firstly, the  20 year hiatus in lander missions on Mars. 


Secondly, there is no point repeating  experiments that were known to be flawed and gave obvious results.  You need to do different experiments.  Specifically testing the primary hypothesis from Viking that the results were from reactive soil chemistry.   All the Mars surface missions since then except Schiaparelli have addressed this question in some way.


To test this hypothesis this you need to get a better handle on soil physics, chemistry, mineralogy, texture, and reactivity.  This has been done:  physics - all missions to some degree; chemistry - Pathfinder, Spirit, Opportunity, Curiosity; mineralogy -  Spirit, Opportunity, Curiosity (plus lesser capabilities on  Pathfinder, Phoenix); texture -  Curiosity, Phoenix (plus lesser capabilities on Spirit, Opportunity); reactivity - Phoenix. ExoMars, the 2020 NASA rover and the Chinese mission will add to all of these except reactivity,  assuming they are successful of course.

We also need to explore the issue of organic carbon.  This has been done by Phoenix and Curiosity.  We now know it is there.   The 2020 rover and the ExoMars mission will, all being well add to our knowledge in these areas.

We now know that perchlorate explains both the soil reactivity, and the low organic content of the soils.  We know that the surface of Mars is largely uninhabitable by life as we know it and  as we can reasonably imagine.  There may be special regions, but these are relatively rare.

We now are at a position to have another crack at the question, using new techniques in the possible special regions.  But as with Viking it would be a very expensive mission (full cleanliness an sterilisation and the results will probably be ambiguous.  It would need multiple missions  to test  the results.

This is all true but I’d argue that ESA seem to have a somewhat different attitude and or approach to answering this question than NASA. In that they’ve prioritised looking for the possibility of life now on their first rover mission. Which is rather different than looking at the past habitability of Mars which has been NASA’s focus I’d think I would be right in saying.

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #28 on: 01/10/2020 09:38 pm »
Also if someone doesnít want something to look as if itís more than just a personal opinion maybe they should have fully supported their statements more, rather than relying on another poster to do this work for them.

I would have thought on this forum the facts that there was no video from Mars and that is not enough oxygen in the atmosphere to support combustion were sufficiently well known  to not need elaboration.

The fact that Scientific American is a popular magazine not a science journal should be obvious from the content and the front matter.

Quote
This matter could easily be resolved if NASA repeated these or similar experiments on another mission, but hasnít so I regard the matter as still open.

Why has it taken so long is explained by two things.  Firstly, the  20 year hiatus in lander missions on Mars. 


Secondly, there is no point repeating  experiments that were known to be flawed and gave obvious results.  You need to do different experiments.  Specifically testing the primary hypothesis from Viking that the results were from reactive soil chemistry.   All the Mars surface missions since then except Schiaparelli have addressed this question in some way.


To test this hypothesis this you need to get a better handle on soil physics, chemistry, mineralogy, texture, and reactivity.  This has been done:  physics - all missions to some degree; chemistry - Pathfinder, Spirit, Opportunity, Curiosity; mineralogy -  Spirit, Opportunity, Curiosity (plus lesser capabilities on  Pathfinder, Phoenix); texture -  Curiosity, Phoenix (plus lesser capabilities on Spirit, Opportunity); reactivity - Phoenix. ExoMars, the 2020 NASA rover and the Chinese mission will add to all of these except reactivity,  assuming they are successful of course.

We also need to explore the issue of organic carbon.  This has been done by Phoenix and Curiosity.  We now know it is there.   The 2020 rover and the ExoMars mission will, all being well add to our knowledge in these areas.

We now know that perchlorate explains both the soil reactivity, and the low organic content of the soils.  We know that the surface of Mars is largely uninhabitable by life as we know it and  as we can reasonably imagine.  There may be special regions, but these are relatively rare.

We now are at a position to have another crack at the question, using new techniques in the possible special regions.  But as with Viking it would be a very expensive mission (full cleanliness an sterilisation and the results will probably be ambiguous.  It would need multiple missions  to test  the results.

This is all true but Iíd argue that ESA seem to have a somewhat different attitude and or approach to answering this question than NASA. In that theyíve prioritised looking for the possibility of life now on their first rover mission. Which is rather different than looking at the past habitability of Mars which has been NASAís focus Iíd think I would be right in saying.

The Rosalind rover carrieds a laser Raman spectrometer and a gas chromatograph and mass spectrometer (MOMA) to detect organics.  It will not detect "life" as such, but characterise the organic molecules to an u preceden degree (we hope).  It essentially is a modern version of the GCMS on Viking but uses Laser Desorption Mass Spectrometry to liberate the organics, circumventing the issue of thermal decomposition causing reactions between perchlorate and organics.

Apologies in advance for any lack of civility - it's unintended

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #29 on: 01/23/2020 04:14 pm »
Also if someone doesn’t want something to look as if it’s more than just a personal opinion maybe they should have fully supported their statements more, rather than relying on another poster to do this work for them.

I would have thought on this forum the facts that there was no video from Mars and that is not enough oxygen in the atmosphere to support combustion were sufficiently well known  to not need elaboration.

The fact that Scientific American is a popular magazine not a science journal should be obvious from the content and the front matter.

Quote
This matter could easily be resolved if NASA repeated these or similar experiments on another mission, but hasn’t so I regard the matter as still open.

Why has it taken so long is explained by two things.  Firstly, the  20 year hiatus in lander missions on Mars. 


Secondly, there is no point repeating  experiments that were known to be flawed and gave obvious results.  You need to do different experiments.  Specifically testing the primary hypothesis from Viking that the results were from reactive soil chemistry.   All the Mars surface missions since then except Schiaparelli have addressed this question in some way.


To test this hypothesis this you need to get a better handle on soil physics, chemistry, mineralogy, texture, and reactivity.  This has been done:  physics - all missions to some degree; chemistry - Pathfinder, Spirit, Opportunity, Curiosity; mineralogy -  Spirit, Opportunity, Curiosity (plus lesser capabilities on  Pathfinder, Phoenix); texture -  Curiosity, Phoenix (plus lesser capabilities on Spirit, Opportunity); reactivity - Phoenix. ExoMars, the 2020 NASA rover and the Chinese mission will add to all of these except reactivity,  assuming they are successful of course.

We also need to explore the issue of organic carbon.  This has been done by Phoenix and Curiosity.  We now know it is there.   The 2020 rover and the ExoMars mission will, all being well add to our knowledge in these areas.

We now know that perchlorate explains both the soil reactivity, and the low organic content of the soils.  We know that the surface of Mars is largely uninhabitable by life as we know it and  as we can reasonably imagine.  There may be special regions, but these are relatively rare.

We now are at a position to have another crack at the question, using new techniques in the possible special regions.  But as with Viking it would be a very expensive mission (full cleanliness an sterilisation and the results will probably be ambiguous.  It would need multiple missions  to test  the results.

This is all true but I’d argue that ESA seem to have a somewhat different attitude and or approach to answering this question than NASA. In that they’ve prioritised looking for the possibility of life now on their first rover mission. Which is rather different than looking at the past habitability of Mars which has been NASA’s focus I’d think I would be right in saying.

The Rosalind rover carrieds a laser Raman spectrometer and a gas chromatograph and mass spectrometer (MOMA) to detect organics.  It will not detect "life" as such, but characterise the organic molecules to an u preceden degree (we hope).  It essentially is a modern version of the GCMS on Viking but uses Laser Desorption Mass Spectrometry to liberate the organics, circumventing the issue of thermal decomposition causing reactions between perchlorate and organics.

So my categorisation of the differences in approach is correct in a very simplified way.

Offline Star One

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The Labeled Release experiment on the Viking mission
« Reply #30 on: 05/06/2021 11:01 am »
Are viruses alive?

Moves from asking that to how do we define life, to looking for life on other planets via the inconclusive life results of the Viking missions. Talks of how maybe if that experiment had been looking for different things it may have got a more definitive result. I presume they mean the experiment was flawed in that the conception of what is life as defined is arguably flawed as well.

« Last Edit: 05/06/2021 11:02 am by Star One »

Offline deadman1204

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Re: The Labeled Release experiment on the Viking mission
« Reply #31 on: 05/23/2021 03:23 pm »
The experiment was poorly designed.  That is why it failed. Technically it was a null result

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #32 on: 05/23/2021 11:45 pm »
The experiment was poorly designed.  That is why it failed. Technically it was a null result

Based on what was known during the development phase (1960s), it what way was it poorly designed?
Apologies in advance for any lack of civility - it's unintended

Offline Redclaws

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Re: The Labeled Release experiment on the Viking mission
« Reply #33 on: 05/23/2021 11:58 pm »
Are viruses alive?

Moves from asking that to how do we define life, to looking for life on other planets via the inconclusive life results of the Viking missions. Talks of how maybe if that experiment had been looking for different things it may have got a more definitive result. I presume they mean the experiment was flawed in that the conception of what is life as defined is arguably flawed as well.



No, that is not generally whatís meant by that, inspiring as that might be.  It is a much simpler statement than that - the instrument attempted a few simple chemical reactions and observations that were thought would correlate with the presence of what we call life.  The current belief is, basically, they didnít correlate.  They were triggered by what we believe now were abiotic sources.

There is absolutely no issue of the definition of life raised by this.  That is a valid discussion, but nothing in the Viking experimental results brings it in.  The argument is all about whether or not those signals indicated life as traditionally and simply defined, or just some (probably) perchlorates hanging around in the soil.

Offline matthewkantar

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Re: The Labeled Release experiment on the Viking mission
« Reply #34 on: 05/24/2021 01:50 am »
The unsatisfying thing about the Viking labeled release experiments is that no one (to my knowledge) has repeated the results from Mars here on Earth to show the Mars results are possible with chemistry.

Offline libra

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Re: The Labeled Release experiment on the Viking mission
« Reply #35 on: 05/24/2021 06:27 am »
The unsatisfying thing about the Viking labeled release experiments is that no one (to my knowledge) has repeated the results from Mars here on Earth to show the Mars results are possible with chemistry.

But Phoenix found perchlorates in the soil, and it was realized that, when heating a sample (as done by some Viking experiments) perchlorates would destroy organic matter. MSL and others re-did the search for organic matter without heating the soil - and organic matter was found.

The results of Viking went this way

Horowitz: NEGATIVE (no lifeforms)
Oyama: NEGATIVE (no lifeforms)
Levin (labeled release discussed here) : POSITIVE
...
Biemann: NEGATIVE (no organic matter - that experiment did not looked for lifeforms)

While the search for life results were puzzling and deeply split the group of three, the really disturbing controversy that piled up on top was that no organic matter could be found. 

And then the worst happened: the two controversies mixed into a larger one. From my understanding, Horowitz somewhat used the lack of organic matter to shut Levin for good; and this enraged Levin and his supporters who in turn never gave up, and that's why we have this thread even 45 years later.  ;D ;D

On the Biemann front - where is my organic matter ? - Phoenix in 2008 brought a puzzling answer.

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #36 on: 05/27/2021 03:04 am »
The unsatisfying thing about the Viking labeled release experiments is that no one (to my knowledge) has repeated the results from Mars here on Earth to show the Mars results are possible with chemistry.

But Phoenix found perchlorates in the soil, and it was realized that, when heating a sample (as done by some Viking experiments) perchlorates would destroy organic matter. MSL and others re-did the search for organic matter without heating the soil - and organic matter was found.

The results of Viking went this way

Horowitz: NEGATIVE (no lifeforms)
Oyama: NEGATIVE (no lifeforms)
Levin (labeled release discussed here) : POSITIVE
...
Biemann: NEGATIVE (no organic matter - that experiment did not looked for lifeforms)

While the search for life results were puzzling and deeply split the group of three, the really disturbing controversy that piled up on top was that no organic matter could be found. 

And then the worst happened: the two controversies mixed into a larger one. From my understanding, Horowitz somewhat used the lack of organic matter to shut Levin for good; and this enraged Levin and his supporters who in turn never gave up, and that's why we have this thread even 45 years later.  ;D ;D

On the Biemann front - where is my organic matter ? - Phoenix in 2008 brought a puzzling answer.

It's probably better to saythe LR resultsweresupefrficallyt positive.  Aspects of them do not sit well with biology.

As for theorganics, the mere presence of organics does not, of itself indicate biology.  At the very least there should be some in the regolith from abiogenic synthesis and from infalling meteorites.
Apologies in advance for any lack of civility - it's unintended

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #37 on: 09/29/2023 09:48 am »
Technical overview of the Viking experiments. Apparently three of the four experiments have now had their results moved into the inconclusive bucket. Shame that Viking put NASA off from any attempt at further direct detections of life.


Offline deadman1204

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Re: The Labeled Release experiment on the Viking mission
« Reply #38 on: 10/02/2023 03:01 pm »
Technical overview of the Viking experiments. Apparently three of the four experiments have now had their results moved into the inconclusive bucket. Shame that Viking put NASA off from any attempt at further direct detections of life.


From a scientific standpoint, they made absolutely zero sense (not lookig for life, but how the Viking experiments were done). These were almost PR stunts.
No one knows what was reacting or why. They knew nothing about the substrate. Anyone who reasonably questioned the experiment with only the knowledge of the time would be able to say they weren't very sound experiments.

And thats WELL before you get into the actual microbiological aspect of the entire thing. The experiment basically assumed there was a gigantic population of healithy dormant microbes just waiting to have sugar water dumped on them.
« Last Edit: 10/02/2023 03:03 pm by deadman1204 »

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #39 on: 10/20/2023 02:20 am »
From a scientific standpoint, they made absolutely zero sense (not lookig for life, but how the Viking experiments were done). These were almost PR stunts.
No one knows what was reacting or why. They knew nothing about the substrate. Anyone who reasonably questioned the experiment with only the knowledge of the time would be able to say they weren't very sound experiments.

And thats WELL before you get into the actual microbiological aspect of the entire thing. The experiment basically assumed there was a gigantic population of healithy dormant microbes just waiting to have sugar water dumped on them.

Calling them "almost PR stunts" is not only harsh but unfair.   The search for life on Mars was part of the earliest discussions of planetary missions by thee space science board (1958), and one of the core science goals of the first lander mission proposal in 1962.  NASA Ames established a xenobiology duvision in 1964.  Nearly 18 years of research went into these experiments by Levin, Visniac, Sagan, Rho, Lederberg, Horowitz, Oyama, Biemann, Klein, Soffen, and others.   Their expertise included engineering (Levin), microbiology (Visniac), astronomy (Sagan), biology (Soffen, Rho), molecular biology (Klein, Horowiz), physical chemistry (Biemann), and biochemistry (Oyama, Lederberg).  Lederberg was already a Nobel laurate. 

Expecting the team to know about the substrate was a bit difficult since nobody had landed on Mars before beyond very low resolution polarimetry, scatterometry, and spectrometry from telescopes.  Viking did provide data on texture, spectral response, bulk chemistry and isotope chemistry.

There was not one life experiment but three, plus the mass spectroscopy. They did not assume there was a "gigantic population of healthy dormant microbes", although they did assume that microbes were ubiquitous. The experiments were sensitive enough to detect even very small numbers of viable organisms.  Nor did they all depending on a response by any microbes to having "sugar water dumped on them". The gas exchange experiment studied response to adding of organic (amino acids and sugars) and inorganic (salts) nutrients, both with and without water, the latter wetting the sample.  The labelled release experiment moistened the sample with a single water drop containing seven basic products of the Urey-Miller experiment (none of them sugars).  The pyrolic release experiments did not use either nutrients or water but measured uptake of labelled CO2 and/or CO.

As for any questioning of the experiments " with only the knowledge of the time would be able to say they weren't very sound.", I am not aware there was any.  Even though the details were published prior to launch in peer reviewed journals, along with all the underlying research going back to the late 50s.

« Last Edit: 10/20/2023 06:48 pm by zubenelgenubi »
Apologies in advance for any lack of civility - it's unintended

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