[meteorite-list] New evidence for microbial fossils in Martian meteorite
From: Shawn Alan <photophlow_at_meteoritecentral.com>
Date: Thu, 6 May 2010 18:36:04 -0700 (PDT) Message-ID: <197786.69171.qm_at_web113607.mail.gq1.yahoo.com> Hello Listers, ? I did some looking around about evidence of microbial fossils in Martian meteorites and I found a few articles about magnetite and how science are researching how magnetite can be formed biologically or inorganically on Earth, resulting in magnetite crystals. This evidences has been a leading factor in the debate about ALH84001 and if life did exist on Mars. Here are a couple abstracts I pulled off the Internet down below.......... ? Shawn Alan eBayshop http://my.ebay.com/ws/eBayISAPI.dll?MyEbayBeta&MyEbay=&gbh=1&guest=1 ? ? Origins of magnetite nanocrystals in Martian meteorite ALH84001? ? K.L. Thomas-Keprtaa, , , S.J. Clemetta, , , D.S. McKayb, E.K. Gibsonb and S.J. Wentwortha aESCG at NASA/Johnson Space Center, Houston, TX 77058, USA bKR, ARES, NASA/Johnson Space Center, Houston, TX 77058, USA Received 20 July 2008;? accepted 18 May 2009.? Associate editor: Christian Koeberl.? Available online 16 June 2009. Abstract The Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks. These carbonate disks are believed to have precipitated 3.9?Ga ago at beginning of the Noachian epoch on Mars during which both the oldest extant Martian surfaces were formed, and perhaps the earliest global oceans. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose origins have become the source of considerable debate. One group of hypotheses argues that these magnetites are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of magnetite and carbonate may be unrelated; that is, from the perspective of the carbonate the magnetite is allochthonous. For example, the magnetites might have already been present in the aqueous fluids from which the carbonates were believed to have been deposited. We have sought to resolve between these hypotheses through the detailed characterization of the compositional and structural relationships of the carbonate disks and associated magnetites with the orthopyroxene matrix in which they are embedded. Extensive use of focused ion beam milling techniques has been utilized for sample preparation. We then compared our observations with those from experimental thermal decomposition studies of sideritic carbonates under a range of plausible geological heating scenarios. We conclude that the vast majority of the nanocrystal magnetites present in the carbonate disks could not have formed by any of the currently proposed thermal decomposition scenarios. Instead, we find there is considerable evidence in support of an alternative allochthonous origin for the magnetite unrelated to any shock or thermal processing of the carbonates. ? Title:Magnetite as a prokaryotic biomarker: A review Authors:Jimenez-Lopez,?Concepcion; Romanek,?Christopher?S.; Bazylinski,?Dennis?A. ? Publication:Journal of Geophysical Research, Volume 115, Issue 37, CiteID G00G03 Publication Date:04/2010 Origin:AGU ? Abstract Over the years, nanometer-sized magnetite (Fe3O4) crystals have been recovered from many modern and ancient environments including sediments and soils and even meteorites. In some cases these crystals have been used as ?magnetofossils? for evidence of the past presence of specific microbes. Magnetite nanocrystals can be formed by a number of different biological and inorganic mechanisms resulting in crystals with different physical and magnetic characteristics. Prokaryotes (bacteria) biomineralize magnetite through two methods that differ mechanistically, including: biologically induced mineralization (BIM) and biologically controlled mineralization (BCM). Magnetite nanocrystals produced by BIM are known to be synthesized by the dissimilatory iron-reducing bacteria, are deposited external to the cell, and generally are physically indistinguishable from magnetite particles formed inorganically. BCM magnetites, in contrast, are synthesized by the magnetotactic bacteria and some higher organisms and are precipitated intracellularly as membrane-bounded structures called magnetosomes. These magnetites appear to have unique crystal morphologies and a narrow size range leading to their original use as magnetofossils. Because of the discovery of nanometer-sized crystals of magnetite in the Martian meteorite ALH84001, the use of these criteria for the determination of whether magnetite crystals could constitute a prokaryotic biomarker was questioned. Thus, there is currently great debate over what criteria to use in the determination of whether specific magnetite crystals are biogenic or not. In the last decade, additional criteria have been established (e.g., the Magnetite Assay for Biogenicity), and new tools and technologies have been developed to determine the origin of specific types of magnetite crystals. ? ? ? ? ? [meteorite-list] Fwd: Re: New evidence for microbial fossils in Martian meteoritecdtucson at cox.net cdtucson at cox.net Thu May 6 15:33:09 EDT 2010 Previous message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Next message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] > Everett, > All due respect but this was exactly my point. > ALH84001 does NOT match Martian Oxygen isotopes . The ones within ALH84001 only match a theoretical but different Martian atmosphere. > Only the much younger SNC's match what we know to be Mars Ratios. > "Houston we had a problem" . No problem just say it matches Mar's older atmosphere. Ya, that'll work. NOT! > Sorry but it still looks like a duck to me. How could we possibly know for a fact that Mars once had a different atmosphere that ALH84001 matches? . Sounds like to tail wagging the dog to me. > see link. > " Gas trapped in the meteorite's minerals does not match the ratio of gases of Mar's modern thin atmosphere. Younger meteorites do match." Dr. Ben Weiss. > > http://www.mail-archive.com/meteorite-list at meteoritecentral.com/msg12675.html > > So , again. ALH84001 may or may not be from Mars without a real stretch. ? > > Carl > -- > Carl or Debbie Esparza > Meteoritemax > > > ---- ekgmars at aol.com wrote: > > I would like to offer additional information about why we know ALH84001 is from Mars. In additional to the oxygen isotopes (which the scientific community now recognizes as the standard to recognized various extraterrestrial materials), the trapped noble gases match those previously identified to be from Mars (Bogard and Garrison, LPSC) in other SNC meteorites and the atmospheric gases measured by Viking's mass spectrometers in 1976 and 1977. Selected trace element abundances and ratios also match those recognized to be from Martian materials. The original diogenite classification of ALH84001 was based on a very limited chemical analysis and a single thin section which was not representative of the sample. > > Everett Gibson > > > > > > > > > > > > -----Original Message----- > > From: cdtucson at cox.net > > To: JoshuaTreeMuseum <joshuatreemuseum at embarqmail.com>; meteorite-list at meteoritecentral.com > > Sent: Wed, 5 May 2010 17:32 > > Subject: Re: [meteorite-list] New evidence for microbial fossils in Martian meteorite > > > > > > Phil, > > I have no arguments against your points here but, I do have a few questions. > > With all due respect and hope that I am not too far off base here. > > > > Based on thousands of photos of Mars it seems to be a lot like Earth less the > > water and growies. > > Although there are a lot of places here that do look exactly like Mars. > > Isn't it possible for igneous rocks to become metamorphosed into rocks that > > might be from past oceans on Mars? > > > > One of our probes definitely confirmed the presents of Glauconite and Albite on > > Mars. > > these are also found in Earths oceans. So, I tend to believe a lot of what our > > scientists say. > > Even without extraordinary proof. > > > > To me there are theories being postured that are far more in need of proof than > > the fact that Mar's may have life. Such as. > > . > > The Moon was created by a giant collision with earth? > > What? The Moon is nothing like Earth and what about all of the other planet's > > Moons? > > Did Saturn and Jupiter get hit as well? Wait! How would that work? Aren't they > > Gaseous? What would it have hit? > > > > But the most Crazy theory is that ALH84001 is even from Mars at all. > > It does not match any of the other SNC's in either Mineralogy or Isotopes. Yes, > > it has some like minerals but that should not come as a surprise. > > And Yes, they say if the O- isotopes match, that is diagnostic of origin. > > Problem is that ALH84001's O-isotopes does not match the others. So, how could > > it have the same origin? > > Please explain that one? > > It was first classified as a diogenite because it is very much like a diogenite > > (if it looks like a duck) . But for the some reason it suddenly became a new > > Martian meteorite. > > It may well be from Mars but, if the isotopes don't match the others then how > > could it be? Usually Isotopes rule. Don't they? > > I am asking because I would like to know not to disrespect anybody here. > > Seems to me it may be from a different planet? > > Carl > > -- > > Carl or Debbie Esparza > > Meteoritemax > > > > > > ---- JoshuaTreeMuseum <joshuatreemuseum at embarqmail.com> wrote: > > > Melanie: > > > > > > I think they're just recycling their old claims to try and get more taxpayer > > > funding for their project. I'm still waiting to hear their "new" evidence. > > > It's the same as their old evidence, which is weak. McKay and his crew > > > remind me of Michael Mann and his CRU with their AGW agenda. (Incidently, > > > NASA is involved in Climategate with their questionable Goddard Institute > > > for Space Studies data.) > > > > > > These people are seriously looking for microbial fossils in igneous rock? > > > Has a fossil of any kind ever been found in an igneous rock? Are life forms > > > ever preserved in magma, granite or obsidian? This is laughable at the > > > least. > > > > > > So they found some magnetite crystals. They say 75% were naturally formed > > > by a shock mechanism, while 25% were so perfect, they had to be biogenic. > > > What are the chances of this actually happening? Wouldn't it all be natural > > > or all biogenic? > > > > > > And get this: the magnetite is exactly the same as that produced by > > > magnetotactic bacteria on Earth! So what are the chances of this happening? > > > 2 identical life forms on two different planets. These things live in the > > > ocean, could they survive an interplanetary journey? Why are these magnetite > > > chain fossils not found in sedimentary Earth rocks, but yet they appear in > > > igneous Mars rocks? Since these are aquatic creatures, it seems highly > > > unlikely they would turn up in igneous rock. > > > > > > Their whole argument rests of the morphology of a few magnetite nano > > > crystals, which they claim they can now see better with higher resolution > > > microscopes. I think this is very weak evidence, and I remain unconvinced. > > > I think desktop cold fusion is more likely. > > > > > > Phil Whitmer > > > > > > ______________________________________________ > > > Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html > > > Meteorite-list mailing list > > > Meteorite-list at meteoritecentral.com > > > http://six.pairlist.net/mailman/listinfo/meteorite-list > > ______________________________________________ > > Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html > > Meteorite-list mailing list > > Meteorite-list at meteoritecentral.com > > http://six.pairlist.net/mailman/listinfo/meteorite-list > > > > Previous message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Next message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] More information about the Meteorite-list mailing list ? ? ? ? ? ? ? ? ? ? ? ? ? meteorite-list] Fwd: Re: New evidence for microbial fossils in Martian meteoritecdtucson at cox.net cdtucson at cox.net Thu May 6 15:33:09 EDT 2010 Previous message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Next message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] > Everett, > All due respect but this was exactly my point. > ALH84001 does NOT match Martian Oxygen isotopes . The ones within ALH84001 only match a theoretical but different Martian atmosphere. > Only the much younger SNC's match what we know to be Mars Ratios. > "Houston we had a problem" . No problem just say it matches Mar's older atmosphere. Ya, that'll work. NOT! > Sorry but it still looks like a duck to me. How could we possibly know for a fact that Mars once had a different atmosphere that ALH84001 matches? . Sounds like to tail wagging the dog to me. > see link. > " Gas trapped in the meteorite's minerals does not match the ratio of gases of Mar's modern thin atmosphere. Younger meteorites do match." Dr. Ben Weiss. > > http://www.mail-archive.com/meteorite-list at meteoritecentral.com/msg12675.html > > So , again. ALH84001 may or may not be from Mars without a real stretch. ? > > Carl > -- > Carl or Debbie Esparza > Meteoritemax > > > ---- ekgmars at aol.com wrote: > > I would like to offer additional information about why we know ALH84001 is from Mars. In additional to the oxygen isotopes (which the scientific community now recognizes as the standard to recognized various extraterrestrial materials), the trapped noble gases match those previously identified to be from Mars (Bogard and Garrison, LPSC) in other SNC meteorites and the atmospheric gases measured by Viking's mass spectrometers in 1976 and 1977. Selected trace element abundances and ratios also match those recognized to be from Martian materials. The original diogenite classification of ALH84001 was based on a very limited chemical analysis and a single thin section which was not representative of the sample. > > Everett Gibson > > > > > > > > > > > > -----Original Message----- > > From: cdtucson at cox.net > > To: JoshuaTreeMuseum <joshuatreemuseum at embarqmail.com>; meteorite-list at meteoritecentral.com > > Sent: Wed, 5 May 2010 17:32 > > Subject: Re: [meteorite-list] New evidence for microbial fossils in Martian meteorite > > > > > > Phil, > > I have no arguments against your points here but, I do have a few questions. > > With all due respect and hope that I am not too far off base here. > > > > Based on thousands of photos of Mars it seems to be a lot like Earth less the > > water and growies. > > Although there are a lot of places here that do look exactly like Mars. > > Isn't it possible for igneous rocks to become metamorphosed into rocks that > > might be from past oceans on Mars? > > > > One of our probes definitely confirmed the presents of Glauconite and Albite on > > Mars. > > these are also found in Earths oceans. So, I tend to believe a lot of what our > > scientists say. > > Even without extraordinary proof. > > > > To me there are theories being postured that are far more in need of proof than > > the fact that Mar's may have life. Such as. > > . > > The Moon was created by a giant collision with earth? > > What? The Moon is nothing like Earth and what about all of the other planet's > > Moons? > > Did Saturn and Jupiter get hit as well? Wait! How would that work? Aren't they > > Gaseous? What would it have hit? > > > > But the most Crazy theory is that ALH84001 is even from Mars at all. > > It does not match any of the other SNC's in either Mineralogy or Isotopes. Yes, > > it has some like minerals but that should not come as a surprise. > > And Yes, they say if the O- isotopes match, that is diagnostic of origin. > > Problem is that ALH84001's O-isotopes does not match the others. So, how could > > it have the same origin? > > Please explain that one? > > It was first classified as a diogenite because it is very much like a diogenite > > (if it looks like a duck) . But for the some reason it suddenly became a new > > Martian meteorite. > > It may well be from Mars but, if the isotopes don't match the others then how > > could it be? Usually Isotopes rule. Don't they? > > I am asking because I would like to know not to disrespect anybody here. > > Seems to me it may be from a different planet? > > Carl > > -- > > Carl or Debbie Esparza > > Meteoritemax > > > > > > ---- JoshuaTreeMuseum <joshuatreemuseum at embarqmail.com> wrote: > > > Melanie: > > > > > > I think they're just recycling their old claims to try and get more taxpayer > > > funding for their project. I'm still waiting to hear their "new" evidence. > > > It's the same as their old evidence, which is weak. McKay and his crew > > > remind me of Michael Mann and his CRU with their AGW agenda. (Incidently, > > > NASA is involved in Climategate with their questionable Goddard Institute > > > for Space Studies data.) > > > > > > These people are seriously looking for microbial fossils in igneous rock? > > > Has a fossil of any kind ever been found in an igneous rock? Are life forms > > > ever preserved in magma, granite or obsidian? This is laughable at the > > > least. > > > > > > So they found some magnetite crystals. They say 75% were naturally formed > > > by a shock mechanism, while 25% were so perfect, they had to be biogenic. > > > What are the chances of this actually happening? Wouldn't it all be natural > > > or all biogenic? > > > > > > And get this: the magnetite is exactly the same as that produced by > > > magnetotactic bacteria on Earth! So what are the chances of this happening? > > > 2 identical life forms on two different planets. These things live in the > > > ocean, could they survive an interplanetary journey? Why are these magnetite > > > chain fossils not found in sedimentary Earth rocks, but yet they appear in > > > igneous Mars rocks? Since these are aquatic creatures, it seems highly > > > unlikely they would turn up in igneous rock. > > > > > > Their whole argument rests of the morphology of a few magnetite nano > > > crystals, which they claim they can now see better with higher resolution > > > microscopes. I think this is very weak evidence, and I remain unconvinced. > > > I think desktop cold fusion is more likely. > > > > > > Phil Whitmer > > > > > > ______________________________________________ > > > Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html > > > Meteorite-list mailing list > > > Meteorite-list at meteoritecentral.com > > > http://six.pairlist.net/mailman/listinfo/meteorite-list > > ______________________________________________ > > Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html > > Meteorite-list mailing list > > Meteorite-list at meteoritecentral.com > > http://six.pairlist.net/mailman/listinfo/meteorite-list > > > > Previous message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Next message: [meteorite-list] Large Fireball observed on 6MAY2010 in Argentina Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] More information about the Meteorite-list mailing list Received on Thu 06 May 2010 09:36:04 PM PDT |
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