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Life in Mars confirmed by NASA
Using more advanced instruments, NASA reviews the evidence in marsian meteorites.
This was briefly mentioned last month. The news media did not give it the importance this news merits. If you want to read the scientific papers, and see the electronic microscope photographs please go to: http://www.nasa.gov/centers/johnson/...meteorite.html And when you read this material please remember: "There is no blinder person as the man that doesn't want to see". |
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Life in Mars confirmed by NASA
jacob navia wrote:
Life in Mars confirmed by NASA Well, no. Using more advanced instruments, NASA reviews the evidence in marsian meteorites. This was briefly mentioned last month. The news media did not give it the importance this news merits. If you want to read the scientific papers, and see the electronic microscope photographs please go to: http://www.nasa.gov/centers/johnson/...meteorite.html The two main papers linked from that web page were a very long read indeed, especially to someone with no particular expertise in geochemistry. And when you read this material please remember: "There is no blinder person as the man that doesn't want to see". Pre-insulting anyone who disagrees with your favored conclusions only raises hackles and increases determination in those thus insulted to find some way to oppose those conclusions. The authors seemed to do a splendid job in detail of demolishing arguments others had put forward earlier against the authors' earlier speculations, and I'm modestly persuaded by the pictures that the present conclusions of "life once existed on Mars" may be correct. Well but, Mars is quite a different environment from Earth, in particular the composition of its atmosphere is mostly CO2 with only a trace of O2, in particular, its mantle (and core) has cooled and solidified resulting in different mineral types and compositions there than in the molton mantle of Earth, and so presumably the solid mantle of Mars has very different impact chemistry when large meteor excavations reach mantle-deep than does the fluid mantle of Earth. It is thus perhaps unreasonable to expect that large meteor impacts produced the identical chemical results on Mars as they have done on Earth. In any case, stepping back a bit, the overall argument forms these papers convey creates great unhappiness. They are, after all, purely arguments from ignorance. Consider the arguments of Genesis: we don't know a natural mechanism by which the dry land, the great waters, the sky, the heavens, and the abundant forms of life on Earth were created. Therefore, "goddidit". Compare the arguments in the linked papers: we don't know how the nanoscale carbonate disks and threads, the very pure magnetite microcrystals, could possibly be created by abiotic means. Therefore, "lifedidit". In both cases, some favorite evidence-free hypothesis for the origin of observations in hand is "confirmed" only by being unable to find alternative solutions supported by existing evidence, yet there are infinitely many favorite speculative alternative hypotheses, equally evidence-free, that could just as easily have been chosen to be declared as "proved" by such a flawed argument style. In each case, maybe waiting to see if a more complicated but correct explanation could be found would have been wise. It is also more than a little depressing to think that the universe, and chemistry, are so unimaginative that "life on Mars" should be such a dreary imitation of "life on Earth" that "pure magnetite" would be a tool developed for use by tiny organisms on each, that disks and threads should be the shapes of discovered lifeforms on Mars as they are on Earth. Why did Mars life not shape itself into pentagons, or dodecahedrons, or hollow rings, or fiber bundles? Why did Mars life not use some diamagnetic or gyroscopic steering mechanism? Emotionally, this identity of developed mechanisms used by life rather argues that "life on Earth" and "life on Mars" arose from a single abiogenesis event, developed for quite a while and to quite a level of sophistication containing these common mechanisms, and then traveled one way or the other by meteor=borne cross-contamination. That doesn't do much to remove the lingering suspicion that "we are alone in the universe", now amended with: "except for replications and distributions of our own life chemistry and forms to nearby worlds". FWIW xanthian. |
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Life in Mars confirmed by NASA
Kent Paul Dolan a écrit :
jacob navia wrote: Life in Mars confirmed by NASA Well, no. Using more advanced instruments, NASA reviews the evidence in marsian meteorites. This was briefly mentioned last month. The news media did not give it the importance this news merits. If you want to read the scientific papers, and see the electronic microscope photographs please go to: http://www.nasa.gov/centers/johnson/...meteorite.html The two main papers linked from that web page were a very long read indeed, especially to someone with no particular expertise in geochemistry. And when you read this material please remember: "There is no blinder person as the man that doesn't want to see". Pre-insulting anyone who disagrees with your favored conclusions only raises hackles and increases determination in those thus insulted to find some way to oppose those conclusions. Please, that statement means that you should read those papers with an objective, scientific attitude, not at all as an insult. Treating that as an insult starts the discussion in a polemic note that is not justified. The authors seemed to do a splendid job in detail of demolishing arguments others had put forward earlier against the authors' earlier speculations, and I'm modestly persuaded by the pictures that the present conclusions of "life once existed on Mars" may be correct. OK. Well but, Mars is quite a different environment from Earth, in particular the composition of its atmosphere is mostly CO2 with only a trace of O2, in particular, its mantle (and core) has cooled and solidified resulting in different mineral types and compositions there than in the molton mantle of Earth, and so presumably the solid mantle of Mars has very different impact chemistry when large meteor excavations reach mantle-deep than does the fluid mantle of Earth. It is thus perhaps unreasonable to expect that large meteor impacts produced the identical chemical results on Mars as they have done on Earth. Sure. But that has nothing to do with biology. In any case, stepping back a bit, the overall argument forms these papers convey creates great unhappiness. They are, after all, purely arguments from ignorance. What else do you expect? A detailed biochemical explanation based on marsian life biochemistry? We do not know at all what kind of biochemistry marsian organisms have. We know that each spring, methane is released TODAY by "unknown processes", so the descendants of those organisms must be still around, and in the near future we will be able to argue with more facts than we have now. Consider the arguments of Genesis: we don't know a natural mechanism by which the dry land, the great waters, the sky, the heavens, and the abundant forms of life on Earth were created. Therefore, "goddidit". Compare the arguments in the linked papers: we don't know how the nanoscale carbonate disks and threads, the very pure magnetite microcrystals, could possibly be created by abiotic means. Therefore, "lifedidit". Excuse me but that is a preposterous argument. Magnetite findings, where the chemical composition is similar to magnetite build by living organisms on earth can't be compared with a religious "argument" that exists only in some "holy" books. This is precisely trying to argue without any scientific argument. In both cases, some favorite evidence-free hypothesis for the origin of observations in hand is "confirmed" only by being unable to find alternative solutions supported by existing evidence, yet there are infinitely many favorite speculative alternative hypotheses, equally evidence-free, that could just as easily have been chosen to be declared as "proved" by such a flawed argument style. If there are infinetely many, you should be able to name one... The magnetite evidence, together with the photographs, together with the methane emissions today, together with many other observations give a consistent direction. In each case, maybe waiting to see if a more complicated but correct explanation could be found would have been wise. Why a more complicated explanation would be more correct? This shows just an "apriori" against the life hypothesis. It is also more than a little depressing to think that the universe, and chemistry, are so unimaginative that "life on Mars" should be such a dreary imitation of "life on Earth" that "pure magnetite" would be a tool developed for use by tiny organisms on each, that disks and threads should be the shapes of discovered lifeforms on Mars as they are on Earth. This is a philosophical answer. You do not like the idea of marsian organisms should use similar solutions to detect a magnetic field than organisms on earth. Because... Well yes, because is also more than a little depressing to think that the universe, and chemistry, are so unimaginative But if you agree that the laws of physics are the same here and there, that iron is very abundant both here and there WHY it should be different? Why did Mars life not shape itself into pentagons, or dodecahedrons, or hollow rings, or fiber bundles? Why did Mars life not use some diamagnetic or gyroscopic steering mechanism? Who knows? Maybe both forms of life have the same origin? Emotionally, this identity of developed mechanisms used by life rather argues that "life on Earth" and "life on Mars" arose from a single abiogenesis event, developed for quite a while and to quite a level of sophistication containing these common mechanisms, and then traveled one way or the other by meteor=borne cross-contamination. Maybe. We have no data to prove or disprove that hypothesis. That doesn't do much to remove the lingering suspicion that "we are alone in the universe", now amended with: "except for replications and distributions of our own life chemistry and forms to nearby worlds". FWIW xanthian. When NASA takes us to the next star, we will be able to know for sure :-) |
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Life in Mars confirmed by NASA
jacob navia wrote:
[snipped in toto, see prior posting] You gave nothing persuasive, sufficiently countering to my prior statements, sufficiently indicating that you had even considered my prior statements before responding, or worthy of detailed response. In general, yours was the "true believer" response. I don't think that's a useful way to do or to evaluate science. This conversation is terminated, at least from my end. xanthian. I'm compelled to answer one strange query from you, though: in the case of producing the explanation of the origin of the universe from a knowledge base of pure ignorance, "god did it" can as easily be replaced by "krishna did it" or "the tribe ancestors did it", and in the case of your meteorites, "life did it" can as easily be replaced by "advanced purpose designed abiotic nanotechnology did it", by "magic did it", or by "fred did it. Arguments from ignorance are _worthless_ in exact particular because they provide NO differentiation between explanations for the area where ignorance prevails, so that absolutely _any_ bogus explanation can be stuffed into the gap left by ignorance to replace the unexplained causations. That's why such arguments are unacceptable as science. Proving all the ways something _couldn't_ have happened is not a way of proving how it _did_ happen, because the explanations of how it did happen are potentially uncountably infinite, removing any possibility that the effort of disproving them one by one will ever terminate. |
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Life in Mars confirmed by NASA
I cannot introduce new arguments to the previous dispute
which at least appears to be interrupted. Rather I would like to take this oppurtunity to update what I have learnt so far on meteorites from Mars - to a large part in this newsgroup and especially by J Th more than 5 years ago. I learnt that tha Martian origin of the meteorite ALH84001 and others is derived from isotope ratios in small gas buubles contained in the meteorites. These ratios were different from those in other meteorites but consistent with the atmospheric isotope ratios found by the Viking landers in 1976 and 77. Since those days several new instruments have been landed on Mars in different regions (Pathfinder with Sojourner, the two rovers Spirit and Opportunity, Phoenix) supplying new and probably more accurate data on the atmosphere of Mars. Do the new results support the Martian origin of these meteorites? If ALH84001 wears signs of ancient microbial life on Mars, it might originate from a wet past with a denser atmosphere, i.e. an environment more friendly for life than present. On the other hand, if the observed isotope ratios are those of the present atmosphere, doesn't this support the assumption that the atmosphere in the past was essentially the same as today? Moreover, a grazingly incident meteorite would probably fail to expedit a chunk of surface matter into space through a dense atmosphere. Even if sucessful, the chunk should be thoroughly molten thereby destroying any delicate signatures of life. The situation is different, if the meteorites result from catastrophic impacts like that giving rise to the Hellas Basin. Let us now consider the piece of Martian soil or regolith that landed in Antarctica. How sure can we be that terestrial microbes do not find their way into its interiar through narrow fissures, producing those signstures that have later on be found inside the meteorite in the laboratory? Life is everywhere on Earth, and if the first microbial "attack" failed, there would be sufficient time for many more trials. I would be grateful for any comments and/or links to more information. All the best Jurgen (Barsuhn) |
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Life in Mars confirmed by NASA
Juergen Barsuhn wrote:
I learnt that tha Martian origin of the meteorite ALH84001 and others is derived from isotope ratios in small gas buubles contained in the meteorites. These ratios were different from those in other meteorites but consistent with the atmospheric isotope ratios found by the Viking landers in 1976 and 77. Since those days several new instruments have been landed on Mars in different regions (Pathfinder with Sojourner, the two rovers Spirit and Opportunity, Phoenix) supplying new and probably more accurate data on the atmosphere of Mars. Do the new results support the Martian origin of these meteorites? I don't know (I'm not an expert in this area). However, I do know that the transit time for a meteorite from Mars to get to Earth is quite short -- typically only 10s of millions of years. (This is predicted by celestial-mechanics simulations of meteorite orbital dynamics, and confirmed by explicit measurements of the cosmic ray exposures of these meteorites.) So ALH84001 (and the other dozen-or-so Martian meteorites) only give us samples of the Martian atmosphere from (geologically) present times. Alas, we know almost nothing about what the Martian atmosphere was like billions of years ago. Let us now consider the piece of Martian soil or regolith that landed in Antarctica. How sure can we be that terestrial microbes do not find their way into its interiar through narrow fissures, producing those signstures that have later on be found inside the meteorite in the laboratory? Life is everywhere on Earth, and if the first microbial "attack" failed, there would be sufficient time for many more trials. Yes, this is a hard problem. My understanding (again with the caveat that I'm emphatically not an expert in this area) is that the researchers try rule out terrestrial contamination by looking at how the purportedly--non-terrestrial features are distributed through the volume of the meteorite: If they're more common towards the surface or on fissures, that would argue for Earth-life contamination being plausible. On the other hand, if the features are found even "sealed" inside single mineral grains of non-porous material, and are *not* preferentially found near the meteorite's surface or near fissures, that would argue against Earth-life contamination as their origin. When amino acids have been found in other meteorites, one argument that they were of extra-terrestrial origin was (is) that they're an equal mixture of left- and right-handed stereo-isomers, whereas all Earth life is left-handed. Of course, this argument only proves that those amino acids didn't come from the Earth -- it doesn't say anything about whether natural chemical processes could have produced them elsewhere in the solar system (which is indeed what people who study this say is by far the most likely hypothesis). [Just to be clear, the arguments for and against ancient Martian life traces in ALH84001 et al didn't involve amino acids; I don't think any amino acides have been found in Martian meteorites.] -- -- "Jonathan Thornburg [remove -animal to reply]" Dept of Astronomy, Indiana University, Bloomington, Indiana, USA "Only one carry on? No electronics for the first hour of flight? I wish that, just once, some terrorist would try something that you can only foil by upgrading the passengers to first class and giving them free drinks." -- Bruce Schneier |
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