Author Topic: The Labeled Release experiment on the Viking mission  (Read 24300 times)

Offline Star One

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Yep George Levin has stirred this up again with a new opinion piece in Scientific American.

Quote
On July 30, 1976, the LR returned its initial results from Mars. Amazingly, they were positive. As the experiment progressed, a total of four positive results, supported by five varied controls, streamed down from the twin Viking spacecraft landed some 4,000 miles apart. The data curves signaled the detection of microbial respiration on the Red Planet. The curves from Mars were similar to those produced by LR tests of soils on Earth. It seemed we had answered that ultimate question.
When the Viking Molecular Analysis Experiment failed to detect organic matter, the essence of life, however, NASA concluded that the LR had found a substance mimicking life, but not life. Inexplicably, over the 43 years since Viking, none of NASA’s subsequent Mars landers has carried a life detection instrument to follow up on these exciting results. Instead the agency launched a series of missions to Mars to determine whether there was ever a habitat suitable for life and, if so, eventually to bring samples to Earth for biological examination.

https://blogs.scientificamerican.com/observations/im-convinced-we-found-evidence-of-life-on-mars-in-the-1970s/

Here’s a support article.

https://www.airspacemag.com/daily-planet/debate-over-whether-weve-already-found-life-mars-continued-180973395/

Offline strkiky

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Re: The Labeled Release experiment on the Viking mission
« Reply #1 on: 10/25/2019 09:36 pm »
It's not just George, there's a range of us that wants a reconsideration to the labelled release experiment.

The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets."

That being said, the labelled release experiment does not confirm that there's life on Mars, but it does tell us that introducing urey-miller molecules (as nutrients) to Martian soil results in the release of Carbon dioxide.

But there is a problem when we are no longer considering that there's a possibility to life.

Ever since then, the missions to Mars have being dominated by geological experiments to find "evidence of past life."
Without even thinking that the "evidence of past life" could be indicative of present life.
The instruments we send up there often cannot tell at which point life is possible.

Instruments that could give better indication of life on Mars have being suggested, but they are often pulled out.
(look up Urey: Mars Organic and Oxidant Detector).

We could make far more progress in this area if we actually considered instruments that look for evidence of extant life instead of evidence of past life. This means that we should consider biological or biological-related experiments instead of geological experiments.

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #2 on: 10/25/2019 09:39 pm »
The ExoMars rover does include experiments to look for life does it not

Offline whitelancer64

It's not just George, there's a range of us that wants a reconsideration to the labelled release experiment.

The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets."

That being said, the labelled release experiment does not confirm that there's life on Mars, but it does tell us that introducing urey-miller molecules (as nutrients) to Martian soil results in the release of Carbon dioxide.

But there is a problem when we are no longer considering that there's a possibility to life.

Ever since then, the missions to Mars have being dominated by geological experiments to find "evidence of past life."
Without even thinking that the "evidence of past life" could be indicative of present life.
The instruments we send up there often cannot tell at which point life is possible.

Instruments that could give better indication of life on Mars have being suggested, but they are often pulled out.
(look up Urey: Mars Organic and Oxidant Detector).

We could make far more progress in this area if we actually considered instruments that look for evidence of extant life instead of evidence of past life. This means that we should consider biological or biological-related experiments instead of geological experiments.

The big risk with those types of instruments is that if you bill the mission as "looking for life on Mars" and you don't find it - like the Viking missions did - you get all your funding cut and you don't go to Mars again for the next couple of decades. NASA got burned once doing that and is reticent to do so again.

That said, there ARE a couple of really great "life detection" instruments now, that would look for very specific signatures that would let us know if there is "life as we know it" on Mars. I personally think it would be worthwhile to fly them, the real issue is that NASA doesn't want to deal with the fallout of negative results.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline whitelancer64

The ExoMars rover does include experiments to look for life does it not

It does not.

It has a couple of instruments - the Raman Laser Spectrometer and the Organic Molecule Analyzer - that are very sensitive to organic (carbon-bearing) molecules. Both could in theory detect biosignatures, but that is not their primary purpose.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Online Phil Stooke

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Re: The Labeled Release experiment on the Viking mission
« Reply #5 on: 10/25/2019 10:04 pm »
"The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets.""

Or... that soil chemistry is capable of producing the observed result. 

Until it is clear that soil chemistry alone, without biology, cannot produce the observed result, the assumption that life has been detected is unwarranted.  Let's not overlook the little problem of conflict of interest in Levin's position.  This is not the same as denial.

Offline faramund

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Re: The Labeled Release experiment on the Viking mission
« Reply #6 on: 10/25/2019 10:27 pm »
"The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets.""

Or... that soil chemistry is capable of producing the observed result. 

Until it is clear that soil chemistry alone, without biology, cannot produce the observed result, the assumption that life has been detected is unwarranted.  Let's not overlook the little problem of conflict of interest in Levin's position.  This is not the same as denial.

Although I think the path that science often takes when there are two conflicting theories that can both be used to explain some behaviour, is to develop some sort of test, that dependent on its result, will give more backing to one of the theories over the other.

It seems a failing of the various processes that decide what experimental equipment goes to Mars, that this hasn't been done.

Offline matthewkantar

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Re: The Labeled Release experiment on the Viking mission
« Reply #7 on: 10/26/2019 12:50 am »
"The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets.""

Or... that soil chemistry is capable of producing the observed result. 

Until it is clear that soil chemistry alone, without biology, cannot produce the observed result, the assumption that life has been detected is unwarranted.  Let's not overlook the little problem of conflict of interest in Levin's position.  This is not the same as denial.

As far as I know, nobody has come up with a non-biological explanation of the results, or duplicated the results in the absence of life. Occam's razor here suggests biology is a stronger answer than chemistry.

I have come to believe recently that finding hard evidence of life on some other world won't be as big a deal to the public as is generally thought. Headlines would be headlines for a couple of days and then people would go back to watching the boob tube.

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #8 on: 10/26/2019 06:56 am »
The ExoMars rover does include experiments to look for life does it not

It does not.

It has a couple of instruments - the Raman Laser Spectrometer and the Organic Molecule Analyzer - that are very sensitive to organic (carbon-bearing) molecules. Both could in theory detect biosignatures, but that is not their primary purpose.

Thanks for the clarification. That will teach me to take mainstream articles on it at face value.

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #9 on: 10/26/2019 06:59 am »
"The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets.""

Or... that soil chemistry is capable of producing the observed result. 

Until it is clear that soil chemistry alone, without biology, cannot produce the observed result, the assumption that life has been detected is unwarranted.  Let's not overlook the little problem of conflict of interest in Levin's position.  This is not the same as denial.

As far as I know, nobody has come up with a non-biological explanation of the results, or duplicated the results in the absence of life. Occam's razor here suggests biology is a stronger answer than chemistry.

I have come to believe recently that finding hard evidence of life on some other world won't be as big a deal to the public as is generally thought. Headlines would be headlines for a couple of days and then people would go back to watching the boob tube.

I get the feeling that his article was as much about pointing out that recent NASA Martian missions haven’t included more specific life detecting experiments than anything else.

Offline strkiky

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Re: The Labeled Release experiment on the Viking mission
« Reply #10 on: 10/26/2019 12:11 pm »
Quote
Ghost-like moving lights, resembling will-O’-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)

Offline Nomadd

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Those who danced were thought to be quite insane by those who couldn't hear the music.

Offline libra

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Re: The Labeled Release experiment on the Viking mission
« Reply #12 on: 10/26/2019 06:02 pm »
Ah, Levin... last of the Mohicans, really. All the others - Vishniac, Oyama, Horowitz, and Biemann - are long gone.

Back in 1974 the National Academies had had a prescient warning

"Well, whatif the life seeking instruments give some split results - Oyama, Levin, Horowitz - and then Biemann GCMS fails to find organic molecules in the first place ? how can we justify positive life signs without organic molecules in the first place ?"

And... it happened. The three life seeking experiments gave two resounding NO - Horowitz and Oyama. And then Levin found himself very alone when his own gave a YES signal.
So they called Biemann, somewhat, to the rescue
"Well... how about those organic molecules ?"
"Well, zippo. Nada. Found nothing"

and now they had TWO controversies... "I found life ! " No, you didn't, we didn't ! and by the way, there was organic matter in the first place !"

(facepalm)

Twenty years of paralysis later, in 1997... and then ten more years, 2008... Phoenix land near the north pole... with a new kind of GCMS...

"Hey look, that soil is full of perchlorates !"

"Perchlorates ? hell, those things destroys organics when heated. Pyrolisis, you know, the way Biemann GCMS searched for them..."

"Oh god damn it, can you believe what this mean ??!!! Biemann GCMS exactly destroyed what is was supposed to search, and, how surprising, it did not found it..."
...
"...and then Horowitz used Biemann negative results to rebuke Levin claims, so the two separated controversies tangled together, with catastrophic results..."

"Murphy law, how I hate you."

Offline strkiky

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Re: The Labeled Release experiment on the Viking mission
« Reply #13 on: 10/26/2019 09:35 pm »
Ah, Levin... last of the Mohicans, really. All the others - Vishniac, Oyama, Horowitz, and Biemann - are long gone.

Back in 1974 the National Academies had had a prescient warning

"Well, whatif the life seeking instruments give some split results - Oyama, Levin, Horowitz - and then Biemann GCMS fails to find organic molecules in the first place ? how can we justify positive life signs without organic molecules in the first place ?"

And... it happened. The three life seeking experiments gave two resounding NO - Horowitz and Oyama. And then Levin found himself very alone when his own gave a YES signal.
So they called Biemann, somewhat, to the rescue
"Well... how about those organic molecules ?"
"Well, zippo. Nada. Found nothing"

and now they had TWO controversies... "I found life ! " No, you didn't, we didn't ! and by the way, there was organic matter in the first place !"

(facepalm)

Twenty years of paralysis later, in 1997... and then ten more years, 2008... Phoenix land near the north pole... with a new kind of GCMS...

"Hey look, that soil is full of perchlorates !"

"Perchlorates ? hell, those things destroys organics when heated. Pyrolisis, you know, the way Biemann GCMS searched for them..."

"Oh god damn it, can you believe what this mean ??!!! Biemann GCMS exactly destroyed what is was supposed to search, and, how surprising, it did not found it..."
...
"...and then Horowitz used Biemann negative results to rebuke Levin claims, so the two separated controversies tangled together, with catastrophic results..."

"Murphy law, how I hate you."

This paper refutes most if not all your claims. All those are legitimate issues, but those issues do not withstand the test of time.
http://www.gillevin.com/Mars/Levin-Straat_Mars_Society_Paper_8-8-14.pdf

But I should note that the point is that a few instruments dedicated to actually looking for extant life should be in the payloads.
The concern is that we have never done so since the Vikings is why we're still stuck on this chapter.

Here's a paper that's not by Levin that looks beyond the vikings experiment (spirit, curiosity...etc).
http://journalofastrobiology.com/Mars5.html
- But the issue remains, we've never tried to prove ourself wrong or correct on Mars by providing the specific instruments, so even the evidences presented by Joseph et al., (2019) cannot be experimentally confirmed.
« Last Edit: 10/26/2019 09:39 pm by strkiky »

Offline libra

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Re: The Labeled Release experiment on the Viking mission
« Reply #14 on: 10/27/2019 06:56 am »
It is no *my claims* but rather the broad consensus and general explanation given since 1977 - 42 years of studies. And controversies, admittedly. I did not claimed it was or is the absolute, final answer about Viking results, just the general consensus I come to understand from my readings.
Partly based on that dated but still interesting NASA history
https://history.nasa.gov/SP-4212.pdf

Levine had a peculiar background among the Oyama / Horowitz / Vishniac / Biemann Viking biology team. Basically he was kind of underdog, having single handedly joined the Viking science team from a basic job of... assessing microbial flora levels in Los angeles sewers. No kidding.
The others scientists had more "straightforward" careers through Universities ranks.

Levine, Oyama and Horowitz reactions to Viking puzzling and irritating results is equally interesting. Levine stood against all odds. Horowitz was negative, furious, he somewhat tookover Oyama and Biemann to dismiss Levine results - and they clashed many times. And poor Oyama - he had been the most naive and enthusiast of the lot, and really took a major hit in his morale.

"The current response to The Labeled Release is either in denial or "The world isn't ready to accept that there's life on other planets.""

Or... that soil chemistry is capable of producing the observed result. 

Until it is clear that soil chemistry alone, without biology, cannot produce the observed result, the assumption that life has been detected is unwarranted.  Let's not overlook the little problem of conflict of interest in Levin's position.  This is not the same as denial.

Quote
As far as I know, nobody has come up with a non-biological explanation of the results, or duplicated the results in the absence of life. Occam's razor here suggests biology is a stronger answer than chemistry.

And there the Murphy law strike again... Biemann explanation of the perchlorate - organics reaction (he could not guess in 1977-78, 30 years before Phoenix) was something akin to "perchlorate maybe, but not from Mars: rather from the solvants Martin Marietta & NASA used to sterilize the ovens for pyrolisis"
This did not helped, really, but Biemann could NOT in his right mind found any other explanation for NOT finding organics AND the bizarre results from the ovens when pyrolisis happened.

Some suggested (before Phoenix) that Biemann instrument had not been sensitive enough to detect organics. for the record, Biemann lived until 2016 and he was not exactly happy younger people dared to critic his instrument like this.
He stuck on his 1978 explanation "pyrolisis and perchlorate and organics explain my CGMS results - but where does the perchlorate come ? NASA and Martin Marietta solvants & sterilization stuff"

Phoenix answer 30 years later left everybody in a kind of shock. Biemann had been intuitively right about perchlorates - except for their origin. Mars had done it, not Martin Marietta.  :o  >:(  ::)

And on top of the Biemann vs Horowitz & Oyama vs Levine, tangled controversies - was all the HYPE drummed by Carl Sagan before the mission, since 1960 and voyager beginnings, to get it funded and off the pad. WE GONNA FIND LIFE OF MARS he claimed, for 15 years. NASA drank too much of that hype, they needed Sagan onboard.

And then reality came back in their faces like some kind of giant boomerang. Ouch, it hurts.

Basically, if Viking was to be redone today, it would Biemann, GCMS, and organics first and in force.

And only then, a second mission to cautiously search for life, starting from the organics.

Sorry to say that but both Apollo and Viking, while splendid *PR / engineering / science* successes beyond any doubt, came waaay to early and for the wrong reasons (JFK deadline vs Sagan hype) and in both cases, the frustrating results related to the huge expense ($3 billion for Viking, $25 billion for Apollo) screwed any successor until 1997 (Sojourner) and 1998 (Lunar Prospector).

Makes one think...
« Last Edit: 10/27/2019 07:13 am by libra »

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #15 on: 10/27/2019 08:55 am »
Doesn’t excuse the curious lack of experiments to repeat what Viking was testing for?

Offline libra

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Re: The Labeled Release experiment on the Viking mission
« Reply #16 on: 10/27/2019 04:02 pm »
Yes it excuses it. 
Because a) the hype was way too strong b) the expense was too large and c) all we got in return was a bitting controversy between four scientists for the next four decades before Phoenix lifted a corner of the enigma. 

Also consider that: Viking was the first ever american lander on Mars, and it went into a Mars life (and somewhat, wild goose !) chase straight ahead !

That chase was based (inevitably but also naively) on Earth standard, carbonaceous life - and nothing else. Sagan hoped to find lichens on Mars rocks, and was telling everybody and his dog that the camera was a life-seeking experiment as much as the bio lab. Something will move on the surface !

And then around the time Viking was funded, build, and launched  exoscientists  found a brand new, completely different category of bugs - extremophiles.

On Earth, not on Mars. D'oh !

- first in Antarctica (1973-75, by Wolf Vishniac, actually one of the Viking life scientists that paid his life for his discovery, falling out of cliff while chasing his experiments - by a rather horrible irony, the samples he had recovered that were in turn recovered from his body and backpack nearby - turned the first extremophiles ever found, Antarctica included !)

- and later (1977) in the Pacific depths, near the black smokers (Alvin submarine).
Extremophile discovery was a landmark and proved that not all life on Earth was standard carbon-based thrieving on sun and nutriments. Imagine on others planets, such as Mars !

So yes, the reason why Viking has not been fully repeated, is that it went the wrong way, too early, too naive, at an horrendous cost, and on top of that, produced a very bitting controversy that irritated a lot of people.

Twenty years of paralysis followed, because Congress needed to be allowed to forgot that fiasco, happened just after Apollo, that other big space expense - enough of these space stunts ! Mondale & Proxmire - the usual suspects.

Since then the search for life on Mars has taken a different path - follow the water or find fossile traces. This is much less exciting than Viking "hype" and takes much, much more time but has worked pretty well since 1997.

Viking is really apart in the history of the search of life on Mars. After that big failure, frustration and early dead-end, and a veeeeeryyyy long pause to digest the fiasco, the real hunt started from a clean sheet of paper  in 1997 and has not stopped since then.

Levine should have moved on long ago: he has kind of beating a dead horse for too long. It is understandable he defends his results but if he defends them the wrong way, he doesn't help his cause.
 For example, it is probably hard to staunchly defend data from 1976 when so much probes, instruments and discoveries have been made since them.
There is a very real risk of cutting oneself from more recent discoveries if they run counter from his own results. Or to embrace the ones that favor his results and point of view.

The risk is to become isolated from the mainstream, with only a cottery of followers thinking the same around him.
Marginalization, this is called. Not good for a scientist.
Once again, Levine has an excuse: the post-Viking controversy was extremely harsh and bitting for him, putting him on the defensive for decades. Horowitz in particular was not exactly easy to deal with.

Offline libra

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Re: The Labeled Release experiment on the Viking mission
« Reply #17 on: 10/28/2019 04:40 pm »
I find something in the depth of my HD.

Taken from here

Opportunities and Choices in Space Science, 1974

This is the warning of the National Academies about Viking life search possible results, written in 1974.

Look at the second (or third) document attached, it is worth its weight in gold: The National Academies had somewhat guessed what could happen if

a) 1 out 3 life seeking experiments gave a "YES" and two others, a "NO" (Levine vs Oyama & Horowitz, here we go !)

and what's quite worse...

b) whatif Biemann GCMS gives a NO ? That is, how could we claim "we found life ! we found life !" if organics can't be found in the first place ?

1974... well, this is exactly what happened to Viking !

Unbelievable, and kudos to the National Academies for such a prescient warning.

Offline Star One

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The Labeled Release experiment on the Viking mission
« Reply #18 on: 11/23/2019 07:45 am »
Why We May Have Already Found Life On Mars with Dr Patricia Ann Straat:

« Last Edit: 11/23/2019 07:46 am by Star One »

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #19 on: 12/30/2019 07:31 pm »

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-O’-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-O’-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 you’re 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 you’re 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 you’re 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 hasn’t so I regard the matter as still open.

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.
« 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 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.
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 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.

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 what’s 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 didn’t 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

Offline Jim

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Re: The Labeled Release experiment on the Viking mission
« Reply #40 on: 10/20/2023 01:00 pm »
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.


Completely unknowledgeable post.

Online Emmettvonbrown

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Re: The Labeled Release experiment on the Viking mission
« Reply #41 on: 10/20/2023 02:05 pm »
The arrogance, too - pretty sickening. Must be a SpaceX "rotating wind machine"-"young men"

Offline deadman1204

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Re: The Labeled Release experiment on the Viking mission
« Reply #42 on: 10/20/2023 02:52 pm »
Everyone knew mars was a dead planet WELL before viking. We found that out in the early 60s.

Otherwise, I invite the board experts (jim, emmetvonbrown and others) here to explain why these were "good science". I know your more comfortable just lobbing insults and disagreements and never backing anything up. Super easy to.
« Last Edit: 10/20/2023 02:54 pm by deadman1204 »

Offline Jim

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Re: The Labeled Release experiment on the Viking mission
« Reply #43 on: 10/20/2023 04:11 pm »
Everyone knew mars was a dead planet WELL before viking. We found that out in the early 60s.

Otherwise, I invite the board experts (jim, emmetvonbrown and others) here to explain why these were "good science". I know your more comfortable just lobbing insults and disagreements and never backing anything up. Super easy to.

Sorry shouldn't have posted that but some posts deserve them .   You made the idiotic claim.  The onus is on you to explain why it wasn't "good science" and who is "everybody".    And tell us how you could have done better, without 20/20 hindsight.  And present your credentials as part of your response.


« Last Edit: 10/20/2023 04:50 pm by Jim »

Online Phil Stooke

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Re: The Labeled Release experiment on the Viking mission
« Reply #44 on: 10/20/2023 04:31 pm »
"... explain why these were "good science".

What would you have done with the technology of the day?  What they did was the best that could be done at the time, but if you have better ideas we are all eager to hear them.

"Everyone knew mars was a dead planet WELL before viking. We found that out in the early 60s."

Care to elaborate?  The only early 60s mission you can possibly be referring to is Mariner 4 and it showed us that Mars was cold, dry and cratered, but it certainly didn't show us it was dead.  Jim Lovelock's atmospheric chemistry argument was reasonable if that's what you refer to, but it wasn't proof.

Offline ccdengr

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Re: The Labeled Release experiment on the Viking mission
« Reply #45 on: 10/20/2023 04:35 pm »
It's easy to find problems with the Viking experiments with 20-20 hindsight, but they did the best they could with very limited information and under severe mission constraints.  Definitely they were designed to find "life as we know it" and could have found terrestrial life easily.  It's not true that all three experiments used water -- the pyrolytic release experiment didn't and operated under purely martian conditions.

"We knew Mars was dead in the 60s" -- umm, no.  We knew it was less earthlike than some had thought after Mariner 4, but we don't know that it's dead even today, do we?

https://en.wikipedia.org/wiki/Viking_lander_biological_experiments and links from there are a pretty good summary of the experiments.

Offline zubenelgenubi

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Re: The Labeled Release experiment on the Viking mission
« Reply #46 on: 10/20/2023 06:54 pm »
I remember Bruce Murray stating in his book that some planetary scientists preferred a much better understanding of Martian geology and atmosphere before performing in-situ life detection experiments.

(Second image is from page 61.)

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My opinion: Both. 🤔🙄🫡
« Last Edit: 10/20/2023 07:07 pm by zubenelgenubi »
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Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #47 on: 10/21/2023 01:09 am »
Everyone knew mars was a dead planet WELL before viking. We found that out in the early 60s.

Otherwise, I invite the board experts (jim, emmetvonbrown and others) here to explain why these were "good science". I know your more comfortable just lobbing insults and disagreements and never backing anything up. Super easy to.

You're the one making this claim, so the onus of proof is on you.

First of all who is "everyone" who knew Mars was a dead planet in the early 60s?  Remember this was before the first successful flyby (July 15, 1965) or Lovelock's paper on atmospheric chemistry (August 7, 1965), both quite misleading in many respects.

I have already provided list of good scientists who thought that searching for life on Mars was good science -  Levin, Visniac, Sagan, Rho, Lederberg, Horowitz, Oyama, Biemann, Klein, Soffen.  Note that "good scientists" does not mean they they were right about everything.
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Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #48 on: 10/21/2023 01:23 am »
I remember Bruce Murray stating in his book that some planetary scientists preferred a much better understanding of Martian geology and atmosphere before performing in-situ life detection experiments.

Carl Sagan: Part of the solution?  Or part of the problem?

My opinion: Both. 🤔🙄🫡

Murray was writing from hindsight of course, and at a time prior to the widespread appreciation of extremophiles or post Viking Mars surface data. However he still supported Mars missions to search for life while head of JPL.

Given that both Murray and Sagan founded the Planetary Society and championed planetary exploration and astrobiology through the late 70s and into the 90s, a period where the whole discipline was in the doldrums
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Offline Don2

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Re: The Labeled Release experiment on the Viking mission
« Reply #49 on: 10/21/2023 06:55 am »
I think the biology experiments on Viking were over ambitious for their time. Several mistakes were made.

1/ They lacked a foundation of understanding of the chemistry of the surface, which they needed to design life detection experiments. They did not know how abundant organics were on Mars, or if that abundance increased with depth. They did not know how easy the surface material would be to dig and collect samples from. They did not know how the soil would react to being wetted. They didn't know what the soluble components were, and what types of solutions would form when water was in contact with the soil. They should have started with a smaller, cheaper lander which was focused on understanding the chemistry. The first experiments should have been a GCMS and a wet chemistry experiment similar to what flew on the Phoenix lander. That was the experiment which discovered the perchlorate.

2/ The GCMS team on Viking reported that they did not detect organics. However, that wasn't true. They did detect low levels of chlorinated organics, but those were so unexpected that they concluded that they couldn't possibly be Martian. Chlorinated organics are never produced naturally and are the product of human industry....or so they thought in the 1970s. What they lacked was a robust control experiment that could have proven that those completely unexpected compounds were native to Mars.

3/ There were no follow up missions to investigate the questions raised by the Viking experiments until the Phoenix lander arrived over 30 years later. To this day we still don't know how the soil chemistry varies with depth.

A better strategy would have been to start with a basic, chemistry focused lander. Then follow that up with a more elaborate lander a decade later which would build on the results of the first and do biological experiments.

Offline Star One

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Re: The Labeled Release experiment on the Viking mission
« Reply #50 on: 10/21/2023 09:42 am »
We don’t even know if Mars is a dead planet or not now, let alone the 1960s.

Online Zed_Noir

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Re: The Labeled Release experiment on the Viking mission
« Reply #51 on: 10/21/2023 10:56 am »
<snip>
A better strategy would have been to start with a basic, chemistry focused lander. Then follow that up with a more elaborate lander a decade later which would build on the results of the first and do biological experiments.
Well NASA/JPL got sidetracked with a series of rovers that is mostly for optical and spot surface geology investigations away from a static site.

Also the lander and/or rover that lands on Mars retains the limitations of the Viking EDL (entry, descend & landing) method in payload mass & volume available. Which make chemistry investigations harder and more expensive. AIUI NASA is still using the same Mars EDL method for future Martian landers and/or rovers. That means getting core samples no deeper than a few cm below the Martian surface.

Hopefully in the future there will be bigger Martian landers that can deploy larger rovers capable of more investigations in chemistry and biochemistry deep beneath the Martian surface.

Offline Don2

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Re: The Labeled Release experiment on the Viking mission
« Reply #52 on: 10/21/2023 04:55 pm »
Well NASA/JPL got sidetracked with a series of rovers that is mostly for optical and spot surface geology investigations away from a static site...
.
...Hopefully in the future there will be bigger Martian landers that can deploy larger rovers capable of more investigations in chemistry and biochemistry deep beneath the Martian surface.

The rovers have not been a sidetrack. Curiosity has revolutionized the understanding of Martian organics. Viking detected about 100 parts per billion of chlorinated organics. Curiosity has detected several hundred parts per million of carbon, including single and double ring compounds and macromolecules like kerogen. The long term plan is to solve all the problems with sample return, if it is affordable. If the initial experiments on a returned sample produce confusing results like the Viking experiments did, then new experiments can be devised to resolve the confusion.

There is going to be a presentation on Martian organics at the next AGU meeting. The session abstract says:
Quote
Our understanding of organic matter on Mars has evolved from presumed ‘missing organic molecules’ based on Viking data to a robust library of organic molecules detected over the last decade by the SAM (Sample Analysis at Mars) instrument suite onboard the Mars Science Laboratory (MSL) rover .....

...MSL detections of organics in Gale crater mudstone and sandstones include chlorohydrocarbons up to 300 ppbw; small aliphatic, aromatic, and, sulfur-containing compounds (at 0.1-10 ppmw detections) potentially originating from macromolecular organics and long-chain alkanes from C10 to C12. Total abundance of C is likely higher than individual molecular detections and on the order of 100’s of ppmw. The recent TMAH wet chemistry experiment liberated macromolecular organics, resulting in the detection of one to two-ring aromatic compounds, benzoic acid methyl ester, and benzothiophene. All these detections confirmed the presence of organics in the Martian subsurface, despite exposure to ionizing radiation for at least 80 My...
https://agu.confex.com/agu/fm23/meetingapp.cgi/Paper/1268725

The Exomars rover has a drill capable of going down 2m, so that could explore the vertical distribution of organic compounds, if it ever flies.

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #53 on: 10/22/2023 01:13 am »
I think the biology experiments on Viking were over ambitious for their time. Several mistakes were made.

Agreed, but that is hindsight.  The biology experiments date back to the early 602 and Mariner B.  They were also a prime focus of of these missions. 

Quote
1/ They lacked a foundation of understanding of the chemistry of the surface, which they needed to design life detection experiments. They did not know how abundant organics were on Mars, or if that abundance increased with depth. They did not know how easy the surface material would be to dig and collect samples from. They did not know how the soil would react to being wetted. They didn't know what the soluble components were, and what types of solutions would form when water was in contact with the soil. They should have started with a smaller, cheaper lander which was focused on understanding the chemistry. The first experiments should have been a GCMS and a wet chemistry experiment similar to what flew on the Phoenix lander. That was the experiment which discovered the perchlorate.

Again, hindsight and the limitations of the biology team which included excellent lab biologists, chemists and instrumentation engineers, but limited field microbiology or soil science expertise. GCMS was envisaged from the start with Mariner B.

3/ There were no follow up missions to investigate the questions raised by the Viking experiments until the Phoenix lander arrived over 30 years later. To this day we still don't know how the soil chemistry varies with depth.

A better strategy would have been to start with a basic, chemistry focused lander. Then follow that up with a more elaborate lander a decade later which would build on the results of the first and do biological experiments.
[/quote]

Keep in mind that remote geoscience instrumentation was very limited at the time.  We can look at 60's landers for what was available.  Penetrometers measuring soil strength, alpha backscatter and gamma spectrometers for very basic composition, gamma ray densiometers.  None of this data would have helped better interpret the Viking data and would have been inferior to Viking's XRF system.

Some sort of wet soil chemistry lab might have been possible on Viking, and at the expense of other instruments.  Which would you throw out?  I don't think that sort of very detailed soil behaviour analysis would have been deemed appropriate for initial missions, even if the technology was available.
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Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #54 on: 10/22/2023 01:42 am »
Well NASA/JPL got sidetracked with a series of rovers that is mostly for optical and spot surface geology investigations away from a static site.

I don't think rovers were a side-track.  Even during Viking people saw the need for mobility as landers always come down somewhere safe (i.e. boring), away from the best features.  Viking showed the need for better understanding of the martian surface, those rovers have done that.

Quote
Also the lander and/or rover that lands on Mars retains the limitations of the Viking EDL (entry, descend & landing) method in payload mass & volume available. Which make chemistry investigations harder and more expensive. AIUI NASA is still using the same Mars EDL method for future Martian landers and/or rovers. That means getting core samples no deeper than a few cm below the Martian surface.

EDL technology limits do not preclude fairly sophisticated onboard analysis, as shown by Viking (the like experiments, XRF, GCMS), Phoenix (MECA, TEGA), Curiosity (SAM), and Rosalind (Pasteur).  It does preclude the number of such instruments that can be carried, however.  It does not preclude drilling either, witness Rosalind's 2 m drill.

Quote
Hopefully in the future there will be bigger Martian landers that can deploy larger rovers capable of more investigations in chemistry and biochemistry deep beneath the Martian surface. 

Maybe, though remember that costs tend to go up exponentially with size, the great the complexity of the instruments and the sample preparation the greater the chance of things going wrong, as we have seen with Viking, Phoenix, and Insight.
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Online Zed_Noir

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Re: The Labeled Release experiment on the Viking mission
« Reply #55 on: 10/22/2023 10:39 am »
Well NASA/JPL got sidetracked with a series of rovers that is mostly for optical and spot surface geology investigations away from a static site.

I don't think rovers were a side-track.  Even during Viking people saw the need for mobility as landers always come down somewhere safe (i.e. boring), away from the best features.  Viking showed the need for better understanding of the martian surface, those rovers have done that.

Quote
Also the lander and/or rover that lands on Mars retains the limitations of the Viking EDL (entry, descend & landing) method in payload mass & volume available. Which make chemistry investigations harder and more expensive. AIUI NASA is still using the same Mars EDL method for future Martian landers and/or rovers. That means getting core samples no deeper than a few cm below the Martian surface.

EDL technology limits do not preclude fairly sophisticated onboard analysis, as shown by Viking (the like experiments, XRF, GCMS), Phoenix (MECA, TEGA), Curiosity (SAM), and Rosalind (Pasteur).  It does preclude the number of such instruments that can be carried, however.  It does not preclude drilling either, witness Rosalind's 2 m drill.

Quote
Hopefully in the future there will be bigger Martian landers that can deploy larger rovers capable of more investigations in chemistry and biochemistry deep beneath the Martian surface. 

Maybe, though remember that costs tend to go up exponentially with size, the great the complexity of the instruments and the sample preparation the greater the chance of things going wrong, as we have seen with Viking, Phoenix, and Insight.
IMO. The historical Mars rover series was a sidetrack for biochemistry investigations until the Curiosity rover.

As you stated the current Martian EDL method limited the volume of instruments that can be put in a lander and/or a rover for a mission.

As for the Rosalind 2 m drill. AIUI that was with the Roselind aboard a Russian lander. Can ESA still put a 2 m drill with Rosalind rover landing aboard a NASA lander?

I may be mistaken, there are costs to miniaturized instruments for mass consideration in development and manufacturing for a spacecraft/lander/rover. That is to say a bigger lander or rover don't have to miniaturized instruments as much. Reducing complexity.

Also a big rover might be able to deploy a core drilling rig that can get samples from 5 meters beneath the Martian surface
.

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #56 on: 10/22/2023 11:28 pm »
IMO. The historical Mars rover series was a sidetrack for biochemistry investigations until the Curiosity rover.


I would not say it was a sidetrack, but rather a hiatus until the nature of the martian surface was better constrained WRT physical properties, chemistry, and mineralogy.  As others have here pointed out, with hindsight, such knowledge may have better constrained experimental and instrument design, which they have done, although there were still unpleasant surprises with Phoenix, Curiosity, and Insight.

Quote
As for the Rosalind 2 m drill. AIUI that was with the Roselind aboard a Russian lander. Can ESA still put a 2 m drill with Rosalind rover landing aboard a NASA lander?

Good question (which means I don’t have an answer).  Until I read anything to the contrary, I will assume that modifications will be minimal.  I have not read anything on the actual new lander specs, have you?

[/quote]I may be mistaken, there are costs to miniaturized instruments for mass consideration in development and manufacturing for a spacecraft/lander/rover. That is to say a bigger lander or rover don't have to miniaturized instruments as much. Reducing complexity. [/quote]

Maybe, but remember that many the instruments will still be miniaturised and of course automated compared with their terrestrial counterparts.  So still not cheap.  The more instruments the more time will probably be spent at each site (depending on instrument) therefore fewer sites might be examined overall. There is a trade off.  I suspect Rosalind will cover less ground on Mars than the NASA ones, but we’ll see (assuming it gets there).

Quote
Also a big rover might be able to deploy a core drilling rig that can get samples from 5 meters beneath the Martian surface

Realistically that drilling on Mars will slow, and robotic drilling more than a few cm has a high failure rate, historically (only one of the three Luna deep drilling reached the full depth, Chang’e 5 recovered ~1.5 m out of the target 2.0 m, and don’t forget Insight’s mole fiasco).  This is why Rosalind carries 3 drill stems, with the ability to ditch those that get jammed in the ground.

Drilling provides data on vertical variation, at a high technological cost.  There are easier ways to get much of the information in many cases – by shallow trenching (with robotic arms or even rover wheels), use of natural exposures, etc. 

Are you familiar with the Icebreaker mission proposal?  It seems to be dead in the water, but I thought it was a good way to approach the challenge.

However, we have digressed greatly from the Viking LR experiment, so I will leave it at that.  Happy to chat privately further on possible Mars missions.
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Offline Don2

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Re: The Labeled Release experiment on the Viking mission
« Reply #57 on: 10/23/2023 10:49 pm »
Some sort of wet soil chemistry lab might have been possible on Viking, and at the expense of other instruments.  Which would you throw out?  I don't think that sort of very detailed soil behaviour analysis would have been deemed appropriate for initial missions, even if the technology was available.

Understanding the types of solutions formed when water comes into contact with Martian soil is fundamental to interpreting the results of any experiment that involves wet processing. It also has biological implications. Biochemistry always happens in aqueous solution and pH and solute concentration are really important to biology. There are reasons why acid curdles milk, why salt is added to food to preserve it, or why domestic bleach (sodium hypochlorite dissolved in water) kills microbes. If Martian soil formed very acidic/alkaline solutions, or solutions containing powerful oxidizing agents, then that would affect both chemistry and biochemistry.

The gas exchange experiment on Viking showed that Martian soil releases oxygen when exposed to water vapor. I don't think they have ever explained that result. I suppose the current strategy to follow up on that result is to return a sample.

All my comments about the Viking life experiments would also apply to any Europa lander that does astrobiology. The chemistry of the Europa surface is poorly known. Some of the things that are suspected, like sulfuric acid and hydrogen peroxide, are likely to destroy organic molecules, especially if heated.

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #58 on: 10/24/2023 05:37 am »

Understanding the types of solutions formed when water comes into contact with Martian soil is fundamental to interpreting the results of any experiment that involves wet processing. It also has biological implications. Biochemistry always happens in aqueous solution and pH and solute concentration are really important to biology. There are reasons why acid curdles milk, why salt is added to food to preserve it, or why domestic bleach (sodium hypochlorite dissolved in water) kills microbes. If Martian soil formed very acidic/alkaline solutions, or solutions containing powerful oxidizing agents, then that would affect both chemistry and biochemistry.

The gas exchange experiment on Viking showed that Martian soil releases oxygen when exposed to water vapor. I don't think they have ever explained that result. I suppose the current strategy to follow up on that result is to return a sample.


It's been done.  Radiation damaged perchlorate duplicates the results of the Viking biology experiments quite well - and the GCMS.

https://phys.org/news/2013-11-habitable-mars-view-viking.html

https://www.lpi.usra.edu/meetings/lpsc2013/pdf/2664.pdf

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Online Emmettvonbrown

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Re: The Labeled Release experiment on the Viking mission
« Reply #59 on: 10/24/2023 06:08 am »
What is interesting too is Biemann take on the matter - in 1978 and near the end of his life: since he lived long enough to heard about that perchlorate thing : he died in 2016.

https://en.wikipedia.org/wiki/Klaus_Biemann

When he made his conclusions in 1978 he wasn't that far off the mark (with 20/20, 100% hindsight of course !).
I mean, he had the correct intuition: that some solvant inside his instrument ovens had destroyed the organics when actually looking at them - and quite logically brought a negative result.
He just got the "hot solvant" wrong. He suggested it was NASA chemicals used to sterilize the ovens. Not quite: it was from Mars itself: perchlorates...   :o

Biemann himself had a interesting debate with other scientists, related to perchlorates and his instrument. Must have been fascinating to get new results after 30 years (1978 - 2008) but also perhaps a little painful.

https://www.google.com/search?q="klaus+biemann""perchlorates"

[zubenelgenubi: Wow! Very overly-long search thread truncated.]
« Last Edit: 10/25/2023 12:01 am by zubenelgenubi »

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #60 on: 11/20/2023 12:28 am »
What is interesting too is Biemann take on the matter - in 1978 and near the end of his life: since he lived long enough to heard about that perchlorate thing : he died in 2016.

https://en.wikipedia.org/wiki/Klaus_Biemann

When he made his conclusions in 1978 he wasn't that far off the mark (with 20/20, 100% hindsight of course !).
I mean, he had the correct intuition: that some solvant inside his instrument ovens had destroyed the organics when actually looking at them - and quite logically brought a negative result.
He just got the "hot solvant" wrong. He suggested it was NASA chemicals used to sterilize the ovens. Not quite: it was from Mars itself: perchlorates...   :o

Biemann himself had a interesting debate with other scientists, related to perchlorates and his instrument. Must have been fascinating to get new results after 30 years (1978 - 2008) but also perhaps a little painful.

https://www.google.com/search?q="klaus+biemann""perchlorates"

[zubenelgenubi: Wow! Very overly-long search thread truncated.]

Rafael Navarro-González and Chris McKay responded to Biemann's comments

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2011JE003880
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Online Emmettvonbrown

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Re: The Labeled Release experiment on the Viking mission
« Reply #61 on: 11/21/2023 04:01 am »
The exchange was nail bitting at times. Not easy perhaps for Biemann, near the end of his life, to reopen the case he thought he had closed in 1978 (NASA solvants). Old wounds.

Offline Eric Hedman

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Re: The Labeled Release experiment on the Viking mission
« Reply #62 on: 02/08/2024 07:40 am »
What I have wondered about on recent Mars probes is why don't they put a microscope on board that could see a microbe in the samples collected.  There are desktop electron microscopes available that could do the job.  Do they draw too much power to be carried onboard?  Can they not be miniaturized enough?  Would it be too difficult to prepare a sample for viewing?  I am just curious if anyone knows the answer.

Offline whitelancer64

What I have wondered about on recent Mars probes is why don't they put a microscope on board that could see a microbe in the samples collected.  There are desktop electron microscopes available that could do the job.  Do they draw too much power to be carried onboard?  Can they not be miniaturized enough?  Would it be too difficult to prepare a sample for viewing?  I am just curious if anyone knows the answer.

Several Mars probes have had microscopes. The Phoenix lander had two microscopes, an optical one and an atomic force microscope. Spirit and Opportunity both had microscopic imagers. Curiosity's MAHLI has a maximum resolution of 14 microns per pixel. Perseverance's SHERLOC has a context camera with a maximum resolution of 10 microns per pixel.
« Last Edit: 02/08/2024 03:40 pm by whitelancer64 »
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Offline Eric Hedman

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Re: The Labeled Release experiment on the Viking mission
« Reply #64 on: 02/09/2024 01:08 am »
What I have wondered about on recent Mars probes is why don't they put a microscope on board that could see a microbe in the samples collected.  There are desktop electron microscopes available that could do the job.  Do they draw too much power to be carried onboard?  Can they not be miniaturized enough?  Would it be too difficult to prepare a sample for viewing?  I am just curious if anyone knows the answer.

Several Mars probes have had microscopes. The Phoenix lander had two microscopes, an optical one and an atomic force microscope. Spirit and Opportunity both had microscopic imagers. Curiosity's MAHLI has a maximum resolution of 14 microns per pixel. Perseverance's SHERLOC has a context camera with a maximum resolution of 10 microns per pixel.
Is it safe to assume that none of these have imaged anything that looks like a microbe on Mars?

Offline Dalhousie

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Re: The Labeled Release experiment on the Viking mission
« Reply #65 on: 02/15/2024 01:38 am »
What I have wondered about on recent Mars probes is why don't they put a microscope on board that could see a microbe in the samples collected.  There are desktop electron microscopes available that could do the job.  Do they draw too much power to be carried onboard?  Can they not be miniaturized enough?  Would it be too difficult to prepare a sample for viewing?  I am just curious if anyone knows the answer.

Several Mars probes have had microscopes. The Phoenix lander had two microscopes, an optical one and an atomic force microscope. Spirit and Opportunity both had microscopic imagers. Curiosity's MAHLI has a maximum resolution of 14 microns per pixel. Perseverance's SHERLOC has a context camera with a maximum resolution of 10 microns per pixel.
Is it safe to assume that none of these have imaged anything that looks like a microbe on Mars?

Bacteria are typically 3-4 microns so these instruments could not resolve them.  Mineralised microbial cells or filaments are larger and could, in principle, be imaged. 
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