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Selfsim
2013-Jun-18, 12:18 AM
I found this interesting report the other day .. I have no idea how/why it slipped thru the media reporting chain, given the scope of its implications. Its all about recent radioisotopic analysis of the carbon in shock fractures of the Tissint meteorite (Martian origin):

NANOSIMS ANALYSIS OF ORGANIC CARBON FROM MARS: EVIDENCE FOR A BIOGENETIC ORIGIN. (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/1476.pdf)

('Twas presented at the Lunar/Planetary Science Conference (2013) .. I have no idea as to whether it was peer reviewed or not .. but it looks legitimate).


Laser micro-Raman spectra of the carbon component indicate a kerogen-like matter, similar to those reported in “magma inclusions” in other Martian meteorites. We analyzed the elemental ratios of H, N, O, F, Cl, S and P to C, and the isotopic compositions of C, N and H using the nanoSIMS 50L. The results clearly favor a biogenetic origin.Figure 2 in the paper shows at a glance, the isotopic signature leaning towards biogenic origins.

(Certainly 'throws monkey on the backs' of those looking for complex carbon based organics with a radioisotope analysis capability, in Gale crater eh?)

Selfsim
2013-Jun-19, 11:58 PM
So the story developed for this rock is rather intriguing ...


The petrographic settings of the organic carbon point to the following formation episodes:

(1) Eruption of the igneous rock of Tissint to the subsurface of Mars;
(2) After a long period of residence (> Ma), the igneous rock was impacted by an asteroid, highly fractured the rock and inducing partial melting;
(3) Hereafter, the host rock of Tissint was infiltrated by organic-bearing fluids;
(4) Organic carbon deposited from the fluid;
(5) A second asteroid hit the same site, partially melting the organic carbon-bearing host rock and producing the shock-melt veins. The presence of the organic carbon inclusions in the shock melt veins set a clear lower limit of formation time for the organic carbon. The RamanT2G band at 1327 cm-1 in some areas of the organic carbon inclusions indicates conversion to diamond by the shock event, similar to the observations in samples of Tissint and other shergottites;
(6) Finally, a third asteroid impacted the igneous rock again, launching Tissint into an Earth crossing orbit at 0.7±0.3.
In addition, petrographic textures of the high-pressure polymorph assemblages in these Martian meteorites strongly suggest multiple shock events, consistent with the above scenario of the organic carbon.
So, I guess the 'kerogen-like organic carbon' doesn't necessarily have to have been extant to Mars … ie: following the initial volcanic eruption(?) … Maybe it came with the impacting Meteors(?), although they point out that:
However, impact of carbonaceous chondrite-like asteroids would destroy its own organic materials. In fact, not any relics of chondritic materials were ever reported in shergottites. … This is the first time I've seen it stated as fact that organics are destroyed in impacts, however the justification for this, seems to be the lack of organic carbon in the Shergotties! If organic carbon is destroyed in impacts, then the expectation of finding surface Martian organics (from Asteroid impacts .. not extant to Mars) should be 'unlikely', no? … Perhaps someone should tell the MSL Curiosity folk this also, eh?

Colin Robinson
2013-Jun-20, 04:21 AM
I found this interesting report the other day .. I have no idea how/why it slipped thru the media reporting chain, given the scope of its implications. Its all about recent radioisotopic analysis of the carbon in shock fractures of the Tissint meteorite (Martian origin):

NANOSIMS ANALYSIS OF ORGANIC CARBON FROM MARS: EVIDENCE FOR A BIOGENETIC ORIGIN. (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/1476.pdf)



('Twas presented at the Lunar/Planetary Science Conference (2013) .. I have no idea as to whether it was peer reviewed or not .. but it looks legitimate).

Figure 2 in the paper shows at a glance, the isotopic signature leaning towards biogenic origins.

(Certainly 'throws monkey on the backs' of those looking for complex carbon based organics with a radioisotope analysis capability, in Gale crater eh?)

Interesting, yes, but it does have a precedent. The Martian meteorite ALH 84001 besides its alleged micro-fossils also contains organic compounds which some scientists have considered to be biological and Martian in orgin, though other scientists have remained unconvinced.

See

BIOMARKERS IN ALH84001 ??? Allan H. Treiman (http://mars.jpl.nasa.gov/mgs/sci/fifthconf99/6019.pdf)

Selfsim
2013-Jun-20, 06:46 AM
Interesting, yes, but it does have a precedent. The Martian meteorite ALH 84001 besides its alleged micro-fossils also contains organic compounds which some scientists have considered to be biological and Martian in orgin, though other scientists have remained unconvinced.

See BIOMARKERS IN ALH84001 ??? Allan H. Treiman (http://mars.jpl.nasa.gov/mgs/sci/fifthconf99/6019.pdf)Hmm ... interesting, although the Lin/Goresy etal paper post-dates the Treiman paper by ~ 10 years! Here's Treiman's 2003 update on the original 1996 McKay paper:

(http://planetaryprotection.nasa.gov/summary/alh84001)
In conclusion, no available data compel acceptance of any argument of McKay et al, so there is no reason to accept its hypothesis.(Love his candour .. its my kinda style, y'know .. ;) :)).

Anyway, the 2013 Lin/Goresay etal paper says:

... This is the first discovery of confirmed organic carbon deposited in fractures in a Martian rock.... That doesn't leave much room for alternative interpretations! It also appears that some 16 scientists (Chinese?) have signed off on this statement, and the paper also cites Swiss, German and Japanese laboratory analyses, to back it up. We don't seem to be reliant on the usual McKay style hypotheses/speculations as an interpretation basis. The conclusion in the Lin/Goresay paper is based on the data .. not hypotheses (which was the original objection to the McKay study, raised by Treiman in 2003).

Also, check out Figure 2 in the Lin/Goresay paper. It shows the http://cosmoquest.org/forum/vlatex/pics/6_77a3b715842b45e440a5bee15357ad29.png13C content for the ALH84001 carbonates (as a comparison) ... this appears to be substantially less 'biogenic' than those for the Tissint meteorite (organic kerogen/carbon) anyway.

I'm left wondering whether/what is the evidence that these meteorites actually originated from Mars at all(??) Is such 'evidence' more solid than the measurements themselves(?) ... I find myself doubting that! ..

Selfsim
2013-Jun-20, 07:37 AM
I suppose this 'Martian organics' story is at least roughly consistent with Mars being warmer and wetter, around the 4-3 Gya timeframe, though.

Interestingly, it also seems that the Martian surface may have been oxidised very early in the history of the planet, although a subduction recycling process has been invoked to explain how even more oxygen got back to the surface following volcanic eruptions at around the ~4Gya timeframe. The old Gusev crater surface rocks, found by the Spirit rover, were from a more oxygen rich environment than the younger Martian meteorites, so they conclude that the meteorites appear to have come from deeper inside the Mars mantle (and are thus thought to be less effected by this subduction recycling process ... which was a surprise).

This recent report is here:

Volcanism on Mars controlled by early oxidation of the upper mantle (http://www.nature.com/nature/journal/v498/n7454/full/nature12225.html)

… Here we show, however, that the differences between the compositions of meteorites and surface rocks can be explained by differences in the oxygen fugacity during melting of the same sulphur-rich mantle. This ties the sources of Martian meteorites to those of the surface rocks through an early (>3.7 billion years ago) oxidation of the uppermost mantle that had less influence on the deeper regions, which produce the more recent volcanic rocks.
… reported in the media headlines as: (http://phys.org/news/2013-06-mars-oxygen-rich-atmosphere-million-years.html)

Professor Wood said: 'The implication is that Mars had an oxygen-rich atmosphere at a time, about 4000 million years ago, well before the rise of atmospheric oxygen on earth around 2500 million years ago. As oxidation is what gives Mars its distinctive colour it is likely that the 'red planet' was wet, warm and rusty billions of years before Earth's atmosphere became oxygen rich.'So, maybe if the Tissint meteorite does actually contain organic carbon produced by Mars itself (which I'm doubting somewhat), then this organic carbon was laying around in an already oxidised Martian surface environment, (prior to the volcanic even more oxygenating resurfacing/subduction process 4Gya), which was producing such organics even before Earth was(?)
This doesn't really stack up for me!

TooMany
2013-Jun-20, 11:02 PM
Interesting, yes, but it does have a precedent. The Martian meteorite ALH 84001 besides its alleged micro-fossils also contains organic compounds which some scientists have considered to be biological and Martian in orgin, though other scientists have remained unconvinced.

See

BIOMARKERS IN ALH84001 ??? Allan H. Treiman (http://mars.jpl.nasa.gov/mgs/sci/fifthconf99/6019.pdf)

New discoveries are accepted only after a protracted battle with skeptics. Some will insist on viable specimens regardless of indirect evidence. I would encourage people like McKay. Even if they are proved wrong nothing is lost by assuming a hypothesis and seeking evidence that supports it.

TooMany
2013-Jun-20, 11:08 PM
So, maybe if the Tissint meteorite does actually contain organic carbon produced by Mars itself (which I'm doubting somewhat), then this organic carbon was laying around in an already oxidised Martian surface environment, (prior to the volcanic even more oxygenating resurfacing/subduction process 4Gya), which was producing such organics even before Earth was(?)
This doesn't really stack up for me!

One would expect the development of Mars to have a much different timeline from Earth because Mars is so much smaller. The surface should have cooled faster than the surface of Earth. Possibly Mars presented a life-friendly environment earlier than Earth.

What do you find to doubt about the organics in the Tissint meteorite?

Selfsim
2013-Jun-21, 12:20 AM
One would expect the development of Mars to have a much different timeline from Earth because Mars is so much smaller. The surface should have cooled faster than the surface of Earth. Possibly Mars presented a life-friendly environment earlier than Earth.Well, I hesitate about getting into the philosophical discussion (for once :p :)), but the reason you choose above, is only one of many (if not, infinite) reasons for why Mars' development would be different from Earth's (from a biogenics viewpoint). I mean theoretically, there are infinite timelines possible, and as we don't know what the causal connections between 'life friendly environments' and the emergence of life are in detail, all reasons should be considered as equally likely. Preferring one over another, implies some particular knowledge or assumption(s) having precedented data … and there is none pertaining to the isotopic ratios of carbon based organics on Mars. Getting this data, is the purpose for exploring Mars in the way it is presently being explored, is it not?

Put simply, it won't 'stack up for me', until a rover detects the same type of kerogen/carbon organics, (isotopic carbon ratio-wise), on Mars.


What do you find to doubt about the organics in the Tissint meteorite?Oh, the organics exists in the sample studied .. I'm not questioning that … However, where it came from, I think, is a topic representing considerable doubt. What exactly is the evidence that the meteorite actually did in fact, originate from Mars?
From a quick read of Wiki, (http://en.wikipedia.org/wiki/Mars_meteorite#History) it seems that this Treiman guy, might be behind the idea that the SNC meteorites did originate from Mars, (and it would seem his reasons are certainly not devoid of uncertainty …)

.. In 2000, an article by Treiman, Gleason and Bogard gave a survey of all the arguments used to conclude the SNC meteorites (of which 14 had been found at the time) were from Mars. They wrote, "There seems little likelihood that the SNCs are not from Mars. If they were from another planetary body, it would have to be substantially identical to Mars as it now is understood."So, given that our understanding of Mars is substantially changing as we speak, the uncertainty in the assumptions underpinning the idea that the meteorites came from Mars is growing, (as long as repeated sample analysis finds no significant organics(?) ).

I would say that the exploration of the geochemistry of Mars represents the test of the hypothesis that these meteorites originated from Mars.
Surely the idea that they might have came form somewhere else, has not been ruled out (regardless of what he thinks may be likely/unlikely)?

Selfsim
2013-Jun-21, 07:45 AM
Here's another report tabled at the same conference as the Lin/El Goresy et al study:

Organic Carbon Inventory of the Tissint meteorite: (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/2854.pdf)


Pyrolysis Gas Chromatigraphy Mass Spectrometry (GCMS) studies are currently underway and the preliminary results
appear to correlate nanoSIMS and ToFSIMS spatially resolved data that indicate that the Tissint meteorite has an inventory of organic carbon and nitrogen compounds indigenous to the meteorite. Whatever the formation mechanism of the mineral associated mineral assemblages it is clear that the presence of clays and sulfates within the inclusion favors a hydrothermal origin for the formation organic carbon and nitrogen species.

There's been A LOT of work done on the Shergottite Group of meteorites. It seems much of it was reported at the same sub-group meeting as the OP Tissint report.

Here's a list of the other reports (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/sess302.pdf) tabled at the conference. One goes into a lot of detailed analysis in order to verify that the collection of meteorites known as 'Shergottites', (which includes the Tissint one), are in fact of Martian origin, (based largely on synergies with Spirit's Gusev crater measurements).

I'm now convinced these reports are definitely 'legitimate' studies ... and the findings are therefore quite astounding!

I'm at a loss as to why the findings have such a low profile!?! Perhaps the ALH84001 fiasco has caused in this different approach(?)

TooMany
2013-Jun-21, 09:07 PM
I'm at a loss as to why the findings have such a low profile!?! Perhaps the ALH84001 fiasco has caused in this different approach(?)

Could be. It's even better because there is little probability of contamination. Good find.

It is not unusual to find ET organics in meteorites. What is special about these organics aside from the belief that the meteorite originated from Mars?

Noclevername
2013-Jun-21, 09:41 PM
Biogenic or biogenetic?

Paul Wally
2013-Jun-21, 09:53 PM
What is special about these organics aside from the belief that the meteorite originated from Mars?

I think it's got something to do with the fact that life on Earth mostly makes use of light carbon instead of the heavier isotopes. If I understand correctly, they found lots of lighter carbon in this meteorite, indicating possible biogenic origin. I don't know whether this constitutes definitive proof of life though.

Selfsim
2013-Jun-21, 11:11 PM
Biogenic or biogenetic?Good question ... the paper uses "Biogenetic" which is how I named the thread .. then I had second thoughts ... I tried to change the thread title, but the board software won't allow it.
I think the two different terms have the same meaning, though(?)

Selfsim
2013-Jun-21, 11:32 PM
Could be. It's even better because there is little probability of contamination. Good find.From the "Inventory of Organics" report, they say:
Analysis of the amino acid inventory of Tissint proved the presence of amino acids of terrestrial origin (SOM Fig 4). Since the amino acid extraction was from a bulk sample of Tissint, the contaminating amino acids may be tied to the presence of small grains of carbonate from the Moroccan soil where the meteorite landed and comprised ~1.5ppm in total.However, the organic carbon/keorgen contained in the shock cracks, is a different matter .. the GCMS preliminary data also indicates that it is of Martian origin (and this is on top of the independent 'NanoSIMS' isotope analysis, which comes to the same conclusion). The carbon was sealed in the glass .. ie: it was internal to the rock:

Pyrolysis Gas Chromatigraphy Mass Spectrometry (GCMS) studies are currently underway and the preliminary results appear to correlate nanoSIMS and ToFSIMS spatially re-solved data that indicate that the Tissint meteorite has an inventory of organic carbon and nitrogen compounds indigenous to the meteorite.


It is not unusual to find ET organics in meteorites.Nice try ... :)
... But not according to the nanoSIMS report .. they say this is 'a first' as far as associating organics with biogenetic origins.

What is special about these organics aside from the belief that the meteorite originated from Mars?The carbon isotope ratio.
Normally, it would be me saying that it was a belief (that the meteorite originated from Mars) .. but there's another paper, which goes into the intricate and gory details of noble gas isotope analysis (ie: yet another independent analysis study) ... (I haven't read the details yet).

There's more to all this, than just a belief.

Selfsim
2013-Jun-21, 11:40 PM
I think it's got something to do with the fact that life on Earth mostly makes use of light carbon instead of the heavier isotopes. If I understand correctly, they found lots of lighter carbon in this meteorite, indicating possible biogenic origin. I don't know whether this constitutes definitive proof of life though.There's certainly no 'proof of life', but none of the multitude of signatory authors are actually claiming that.

The interesting point is that carbon isotopic analysis is exactly what the SAM/QMS/GCMS on Curiosity is designed to do.
So, if it were to find organic carbon in a rock sample which is also consistent with biogenic origins (within its capability set) .. well, the mind boggles as to what sort of fanfare that would create(?) ... So why hasn't the same happened in this case, I wonder?

Selfsim
2013-Jun-22, 12:57 AM
... Normally, it would be me saying that it was a belief (that the meteorite originated from Mars) .. but there's another paper, which goes into the intricate and gory details of noble gas isotope analysis (ie: yet another independent analysis study) ... (I haven't read the details yet).

There's more to all this, than just a belief.I need to 'true up' what I said here. The Noble Gas Analysis report (Cartwright/Ott etal) (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/2314.pdf) was an analysis of the NWA 7034 'Black Beauty' meteorite (which seems to be unique in its classification .. its a breccia.. ie: not necessarily connected with the Tissint biogenic organics containing meteorite). So, from the report or NWA7034 in particular:

Also, unlike other Martian meteorites, there is a remarkable similarity in bulk composition with Martian rocks and soils measured at Gusev Crater (e.g. [6]), rather than Martian meteorites [3], leading the authors to conclude that NWA 7034 is Martian in origin, but may represent an entirely new Martian meteorite group.
...
Conclusions: Our preliminary noble gas analyses show strong influence of a trapped component with MA, (Martian Atmosphere), composition, confirming a Martian origin for NWA 7034So how do they know the Tissint is from Mars? (See my next post).

Noclevername
2013-Jun-22, 02:13 AM
Good question ... the paper uses "Biogenetic" which is how I named the thread .. then I had second thoughts ... I tried to change the thread title, but the board software won't allow it.
I think the two different terms have the same meaning, though(?)

IIRC, Biogenic means anything originating from life. Biogenetic means living things originating from life.

Selfsim
2013-Jun-22, 02:18 AM
... So how do they know the Tissint is from Mars? (See my next post).
OK, so the Tissint has been confirmed as a 'depleted picritic shergottite'1:
Tissint (Morocco) is the fifth martian meteorite collected after it was witnessed falling to Earth. Our integrated mineralogical, petrological, and geochemical study shows that it is a depleted picritic shergottite similar to EETA79001A. Highly magnesian olivine and abundant glass containing martian atmosphere are present in Tissint. Refractory trace element, sulfur, and fluorine data for the matrix and glass veins in the meteorite indicate the presence of a martian surface component. Thus, the influence of in situ martian weathering can be unambiguously distinguished from terrestrial contamination in this meteorite. Martian weathering features in Tissint are compatible with the results of spacecraft observations of Mars. Tissint has a cosmic-ray exposure age of 0.7 ± 0.3 million years, consistent with those of many other shergottites, notably EETA79001, suggesting that they were ejected from Mars during the same event.Ok, so, how do they know that shergottites are from Mars2? ...

The detective work that eventually connected a small group of strange achondritic meteorites to a fairly well known planet is a remarkable philosophical achievement. Actually, solving this case depended on a relatively unheralded measurement by the two NASA Viking spacecraft that landed on Mars in 1976. Although sent to conduct experiments to detect extant life in Martian soil (which they did not), the Viking landers gained redemption of sorts because the instruments measured the amounts of different gases in the thin Martian atmosphere. Those same gases were first found in 1983 by Donald Bogard and Pratt Johnson in very small amounts (but in the exact same proportions) trapped within shock glass veins and pockets in shergottite Elephant Moraine 79001, and now in at least five other Martian meteorites (see plot).
...
So what about all of the other alleged Martian meteorites? It turns out that all of them have kinship based on several other diagnostic criteria:
(1) they all contain iron-rich oxide minerals (magnetite, chromite, ilmenite) and no iron in metallic form;
(2) they all contain an iron sulfide mineral called pyrrhotite, instead of troilite (as found typically in iron metal-bearing meteorites);
(3) the pyroxene and olivine minerals within them have ratios of Fe (iron) to Mn (manganese) that are distinctive (see plot below),
and mostly significantly:
(4) they have a narrow range of oxygen isotopic compositions different from those of any other achondritic meteorites (see plot below).

Taken together, these forensic measures constitute a preponderance of evidence that all the 67 or so proposed Martian meteorites are from the same body, and the atmospheric gas evidence proves beyond doubt that the body is in fact Mars. Thus, unlike the case for lunar meteorites, we have the curious circumstance of knowing that these specimens come from Mars even though humans have not yet obtained directly any rock samples from there. Even more intriguing is the fact that none of the Martian meteorites (possibly with one exception) seem to be very similar to the rock outcrops at any landing sites explored so far with robotic craft. However, the bulk FeO/MnO ratios for the freshest rocks at Gusev crater are very similar to the bulk FeO/MnO ratios for shergottites, providing another very strong link.


References:
1. Tissint Martian Meteorite: A Fresh Look at the Interior, Surface, and Atmosphere of Mars (http://www.sciencemag.org/content/338/6108/785)
2. Martian Meteorites (http://www.imca.cc/mars/martian-meteorites.htm)

Selfsim
2013-Jun-22, 02:29 AM
IIRC, Biogenic means anything originating from life. Biogenetic means living things originating from life.Ok ... so, the organic material they've analysed is Kerogen: (http://en.wikipedia.org/wiki/Kerogen#Formation_of_kerogen)
At the demise of living matter, such as diatoms, planktons, spores and pollens, the organic matter begins to undergo decomposition or degradation. In this break-down process, (which is basically the reverse of photosynthesis [6]), large biopolymers from proteins and carbohydrates begin to partially or completely dismantle. These dismantled components can come together to form new polymers referred to as geopolymers. Geopolymers are the precursors of kerogen.
...
As kerogen is a mixture of organic material, rather than a specific chemical, it cannot be given a chemical formula. Indeed its chemical composition can vary distinctively from sample to sample.Also of interest: (http://en.wikipedia.org/wiki/Kerogen#Extra-terrestrial)

Extra-terrestrial:

Carbonaceous chondrite meteorites contain kerogen-like components. Such material is thought to have formed the terrestrial planets.
Kerogen materials have been detected in interstellar clouds and dust around stars.
.. So the specific material is not necessarily a definitive indicator of its origin (ie: not necessarily "a smoking gun").

TooMany
2013-Jun-22, 04:58 PM
Ok ... so, the organic material they've analysed is Kerogen: (http://en.wikipedia.org/wiki/Kerogen#Formation_of_kerogen)Also of interest: (http://en.wikipedia.org/wiki/Kerogen#Extra-terrestrial).. So the specific material is not necessarily a definitive indicator of its origin (ie: not necessarily "a smoking gun").

But as you mentioned above it's the concentration of light carbon isotopes that argues for biogenesis of this Martian kerogen.

Selfsim
2013-Jun-22, 11:49 PM
In summary, I'd say this is yet another example of how the use of terrestrial-centric scientific distinctions continue to lead towards ambiguous conclusions, when applied outside of a terrestrial environment.

The strategy of using the http://cosmoquest.org/forum/vlatex/pics/6_77a3b715842b45e440a5bee15357ad29.png13C statistic, as a way of distinguishing 'organic' from 'inorganic', on another planet is premature, as it is not effective in eliminating uncertainties of what we don't know about new environments.

The OP study was undertaken, in part, as a reaction to an original paper, (Steele etal 2012), which referred to the carbon as "magma inclusions" (inferring that it was inorganic, thus implicitly eliminating the 'possibility' of it being organic1.

I think we can put the isotopic analysis technique on the pile of other so-called 'smoking gun tests', (along with the likes of Viking's LR metabolism tests), as being yet another inconclusive one, when it comes to remote exo-life detection.

The principle of using Earth-life, (and its specific characteristics), as a model for what to search for elsewhere, limits the field of view of what there is to discern from new, non-terrestrial environments.

That we might even think that they can be remotely executed, to result in meaningful conclusions about the existence of microbial exo-life, would seem to represent a deliberate attempt at continuing to propagate some sort of delusion about real-life remote detection capabilities.


Reference:

1. An update to the 2012 A.Steele (etal) Science paper was presented at the same conference as the OP paper. It is: "A Reduced Organic Carbon Component to Martian Basalts" (http://www.lpi.usra.edu/meetings/lpsc2013/pdf/2659.pdf), A. Steele, McCubbin (etal). This paper continues to refer to the carbon inclusions as "magmatic inclusions", whilst concurring that it is also comprised of mostly light isotopes. It seems to cite another 2006 study by Grady (etal), which found an isotope figure of five times less 'light' carbon, (making it 'less biogenic-like'). Steele uses this study as a reason for it not being "possible to assign a definite value to the concentration and isotope value of Martian organic carbon". Interestingly, the NanoSIMs (Secondary ion mass spectrometry) technology, (used in the OP study), is the latest technology for analyzing the composition of solid surfaces. It has been incorporated in the COSIMA instrument aboard the Rosetta probe .. which is scheduled to 'do its thing' next year, I believe).