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Thread: Water and Organics

  1. #1 Water and Organics 
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    In a thread on water vapour talk turned to presence of water in space. Obviously remarked "Weird that the discussion in this topic changed like this But I'm glad it did. This is quite interesting."

    Since it might be interesting to others I thought I would throw out some thoughts.

    This is a brief summary I gave in that thread:
    As we all doubtless know, hydrogen is the most abundant element in the universe. Oxygen is the third most abundant element. Where temperature is sufficiently low to allow molecular species to survive, water moelcules will form. Water vapour has been detected and found to be common around newly forming stars.

    In the accretion discs of such stars, more distant from the proto-star, temperatures are suffciently low that ices will form. These progressively grow through collision and gravitational attraction, forming planetesimals composed of ices and mineral grains and organic molecules. Some of these contribute to the formation of gas and ice giants, such as Jupiter and Neptune, others will provide the oceans of Earth analogues. while many millions will be cast into the outer darkness of the system as comets.


    Which bore a pleasing symmetry with this abstract:

    Delsemme, A.H. Have comets played a role in the primary organic syntheses? Advances in Space research 1989

    Primary organic syntheses first occurred in interstellar space, where more than sixty different organic molecules have been identified. The most important identifications for prebiotic chemistry probably are HCN, H2CO, CH3CN, C2H2 and CH3C2H, although many others could play important roles. A fraction of these molecules condense, with ubiquitous H2O and CO2, on interstellar grains that follow suit when a molecular cloud collapses gravitationally to form a star. An accretion disk surrounds the growing star, and the frosty interstellar grains are more or less heated depending on their distance to the central star. The innermost loose their water and carbon compounds and will form the rocky planets; those at intermediate distances loose most of their water only, and will form the parent bodies of the carbonaceous chondrites. The outermost keep all their frost and will become the comets. Eventually, the orbits of all those minor bodies diffuse into the inner solar system and bombard the inner rocky planets. Their numerous impacts has brought a veneer that explains the atmosphere and the oceans of the Earth, as well as the source of a wealth of organic compounds. Comets and carbonaceous chondrites are the messengers that have brought down to Earth the products of the primary organic syntheses that were ubiquitous in space.

    The bottom line is that there is a wealth of prebiotic molecules in interstellar space, plus water. There are vast volumes of these in the interstellar clouds, where there is both more time and many orders of magnitude more material, and thus more opportunity, for primitive life to arise and subsequently seed young planets such as the Earth.

    The more research that is carried out in this direction, the more likely I find that the origin of life is out there, not down here.


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    I am responding under BBT, which in most part I do not agree with...

    After BB, as temperatures lowered allowing Hydrogen, Helium and some Lithium to form, production ceased of these basics. All other elements heavier than Lithium were formed as results of solar activity. Until recently Oxygen had not been located anyplace in space and even now is not what should be, based on the high volumes found in local matter.

    If elements for life formed elsewhere, they should have formed here as well, or been here during or after formation. Most feel all those bombarding (asteroids/comets/debris) that where added to the forming of planets/moons where simply left over stuff, from our stars formation and nothing from outside our limits has ever entered from distant space. It could be more complicated, if we formed along with other stars but even then our stars formation, the significance to our make up.

    (opinion) Since I don't disqualify life forming elements floating around on comets, feel most water on earth and other planets probably did come from such objects and do agree our formation or any star is basically a self contained event, I prefer to think element formation come from formation of the star, opposed to the actions from stars...


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    Quote Originally Posted by jackson33
    Until recently Oxygen had not been located anyplace in space and even now is not what should be, based on the high volumes found in local matter. ..
    Oxygen is technically difficult to identify,. this is understood and accounts quite satisfactorily for the current observational dearth.
    Quote Originally Posted by jackson33
    If elements for life formed elsewhere, they should have formed here as well, or been here during or after formation. ...
    They were and they did, which is what is stated in the above post.
    Quote Originally Posted by jackson33
    Most feel all those bombarding (asteroids/comets/debris) that where added to the forming of planets/moons where simply left over stuff, from our stars formation and nothing from outside our limits has ever entered from distant space.
    If most feel this - which I don't think is true - then most are simply wrong. We have clear evidence of 'alien' material.
    Quote Originally Posted by jackson33
    Since I don't disqualify life forming elements floating around on comets, feel most water on earth and other planets probably did come from such objects and do agree our formation or any star is basically a self contained event, I prefer to think element formation come from formation of the star, opposed to the actions from stars...
    i don't follow. Is this in contradiction to anything I have stated?
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    Unless I am not understanding you, your suggesting life on our planet, could have come from some asteroid, carrying the elements from distant space, not of or from our sun. Anything is possible, but IMO and maybe a few others (if you prefer) not likely...

    Of the 30k asteroids with calculated orbits, the entire content of the Asteroid belt (between Mars-Jupiter) or the suspected Oort Clouds, outside the limits of our solar gravity, everything is SUSPECTED to be part of our solar formation. No known object has an orbit around the sun, which leaves the solar system, with Pluto and its moon coming the closest or going deep into the Oort cloud itself.

    The rejected debris from solar formation or as a result would have been equally potential for dispensing elements, whether forming planets, moons or smaller objects. IMO these elements were on our planet, probably all objects, but allowed to propagate under certain conditions.

    The point of my mention of BBT is that solar formation HAD to be for anything other than those first three elements (Hydrogen/Helium/Lithium).
    Taking that to SSU or regeneration of matter, logic tells me the reverse is possible during formation or in the end the same process.

    Note; 99.98% of the solar system mass, is the Sun, .01% is Jupiter and all else is the remaining .09%...

    On objects getting into this solar system; As a system, we travel in open space as a galaxy and have orbited the core of that core about 16-17 times. I would think over 4-5 billion years and all that distance, certainly it would seem possible something could have entered our system and certainly influenced conditions. One global ice age theory suggest passing through a dust cloud, blocking the suns effects and many theory are out there suggesting one thing or another to current structure. We do probably orbit in the galaxy as most any other matter, its thought the Solar Magnetic Field could protect itself- then us, however outside ideas, we have no evidence of any real inter-actions...

    Way I read it...
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  6. #5  
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    Quote Originally Posted by jackson33
    I am responding under BBT, which in most part I do not agree with...

    After BB, as temperatures lowered allowing Hydrogen, Helium and some Lithium to form, production ceased of these basics. All other elements heavier than Lithium were formed as results of solar activity. Until recently Oxygen had not been located anyplace in space and even now is not what should be, based on the high volumes found in local matter.
    I'm not sure I agree that production of Hydrogen would have ceased. I don't see any reason for it to. Any free proton or neutron will invariably attach itself to an electron and become Hydrogen, will it not?

    So, are free protons and/or neutrons not released, ejected, or created in some kind of reaction or another from time to time?
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  7. #6 Re: Water and Organics 
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    Quote Originally Posted by Ophiolite
    In a thread on water vapour talk turned to presence of water in space. Obviously remarked "Weird that the discussion in this topic changed like this But I'm glad it did. This is quite interesting."

    Since it might be interesting to others I thought I would throw out some thoughts.

    This is a brief summary I gave in that thread:
    As we all doubtless know, hydrogen is the most abundant element in the universe. Oxygen is the third most abundant element. Where temperature is sufficiently low to allow molecular species to survive, water moelcules will form. Water vapour has been detected and found to be common around newly forming stars.

    In the accretion discs of such stars, more distant from the proto-star, temperatures are suffciently low that ices will form. These progressively grow through collision and gravitational attraction, forming planetesimals composed of ices and mineral grains and organic molecules. Some of these contribute to the formation of gas and ice giants, such as Jupiter and Neptune, others will provide the oceans of Earth analogues. while many millions will be cast into the outer darkness of the system as comets.


    Which bore a pleasing symmetry with this abstract:

    Delsemme, A.H. Have comets played a role in the primary organic syntheses? Advances in Space research 1989

    Primary organic syntheses first occurred in interstellar space, where more than sixty different organic molecules have been identified. The most important identifications for prebiotic chemistry probably are HCN, H2CO, CH3CN, C2H2 and CH3C2H, although many others could play important roles. A fraction of these molecules condense, with ubiquitous H2O and CO2, on interstellar grains that follow suit when a molecular cloud collapses gravitationally to form a star. An accretion disk surrounds the growing star, and the frosty interstellar grains are more or less heated depending on their distance to the central star. The innermost loose their water and carbon compounds and will form the rocky planets; those at intermediate distances loose most of their water only, and will form the parent bodies of the carbonaceous chondrites. The outermost keep all their frost and will become the comets. Eventually, the orbits of all those minor bodies diffuse into the inner solar system and bombard the inner rocky planets. Their numerous impacts has brought a veneer that explains the atmosphere and the oceans of the Earth, as well as the source of a wealth of organic compounds. Comets and carbonaceous chondrites are the messengers that have brought down to Earth the products of the primary organic syntheses that were ubiquitous in space.

    The bottom line is that there is a wealth of prebiotic molecules in interstellar space, plus water. There are vast volumes of these in the interstellar clouds, where there is both more time and many orders of magnitude more material, and thus more opportunity, for primitive life to arise and subsequently seed young planets such as the Earth.

    The more research that is carried out in this direction, the more likely I find that the origin of life is out there, not down here.
    According to your article above, do you claim that life originates in interstellar space?

    I think life can only originate at temperatures of liquid water from about say 10 degrees Celsius to about 60 degrees Celsius.

    I cannot believe that life could form in icewater.

    Cosmo
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    Quote Originally Posted by kojax
    Quote Originally Posted by jackson33
    I am responding under BBT, which in most part I do not agree with...
    I'm not sure I agree that production of Hydrogen would have ceased. I don't see any reason for it to. Any free proton or neutron will invariably attach itself to an electron and become Hydrogen, will it not?

    So, are free protons and/or neutrons not released, ejected, or created in some kind of reaction or another from time to time?
    'Under BBT', according to Wikipedia, 'Formation of the Universe'...Basically their infering a finite (limited) supply for matter to exist.

    Not only do I feel, hydrogen can be produced today in nature, I feel the said 'stable' elements are not as stable as thought. I use the BBT formula itself, requiring heat, pressures to form other elements, which in reverse should allow for a breakdown. I would agree if offered, that at what ever the smallest parts of matter is determined to be, that should be limited in the Universe. The lightest then an obvious majority, which is true...
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  9. #8 Re: Water and Organics 
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    Quote Originally Posted by Cosmo

    According to your article above, do you claim that life originates in interstellar space?

    I think life can only originate at temperatures of liquid water from about say 10 degrees Celsius to about 60 degrees Celsius.

    I cannot believe that life could form in icewater.

    Cosmo
    I'm sure that organisms have been found to thrive in ice already....on this planet at least....but I'm not sure whether this could be extended to icy asteroids, or whther it is only a result of the ice having close interactions with seawater, and its organisms.
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  10. #9 Re: Water and Organics 
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    Quote Originally Posted by bit4bit
    Quote Originally Posted by Cosmo

    According to your article above, do you claim that life originates in interstellar space?

    I think life can only originate at temperatures of liquid water from about say 10 degrees Celsius to about 60 degrees Celsius.

    I cannot believe that life could form in icewater.

    Cosmo
    I'm sure that organisms have been found to thrive in ice already....on this planet at least....but I'm not sure whether this could be extended to icy asteroids, or whther it is only a result of the ice having close interactions with seawater, and its organisms.
    Well no organisms have been found to really "thrive" in ice, there are psychrophiles that manage to get by though. Ice water is too cold to really be conductive to the evolution of life, moreover phylogenetics shows that those psychrophiles evolved later than hyperthermophiles.

    Organic compounds could have been supplied to the Earth from space though. In fact I believe they have identified organic compounds in meteorites. Also, the famous Urey-Miller experiment has shown that most of the amino acids needed for life can form spontaneously in a reducing atmosphere like that of early Earth.
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    bit4 and tired

    I am not an expert in this field, but I assumed that an organism needed
    a fluid medium to live in.

    Cosmo
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  12. #11  
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    Quote Originally Posted by Cosmo
    bit4 and tired

    I am not an expert in this field, but I assumed that an organism needed
    a fluid medium to live in.

    Cosmo
    Ya, that's why I said ice water, water is needed for them to grow, but some bacteria can survive extended periods of dessication though. Bacteria have been taken from 1000 year old permafrost and were found to still be alive.

    Most cold climate bacteria are lithoautotrophs that live in the microscopic layer of water trapped in rocks or are halophiles that live in pockets of salt water. In Antarctica their are salt water lakes trapped below the ice that are thriving with bacteria, so it is true bacteria can live at extremely cold temperatures, but they still need water to grow.

    After all, if any bacteria/archaea could have made it's way to Earth from let's say Mars, it would have to have been a spore forming cold tolerant bacteria also capable of living in a harsh warm reducing Earth and surviving the intense energy of meteorite impacts, an organism like this simply doesn't exist, nor would it make any evolutionary sense for one to arise.
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  13. #12 Re: Water and Organics 
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    [/quote]
    Organic compounds could have been supplied to the Earth from space though. In fact I believe they have identified organic compounds in meteorites. Also, the famous Urey-Miller experiment has shown that most of the amino acids needed for life can form spontaneously in a reducing atmosphere like that of early Earth.[/quote]

    Probably the most mis-represented discovery of a meteor, was the 1996 NASA Article on the Allen Hills, Antarctica meteor 'ALH 84001'. Said by them at the time 'The biggest scientific discovery in history'. Thought then to have landed about 13k years ago, from Mars, be about 4 Billion years old and containing some primitive form of microscopic life. It was found in 1984...

    Collision of asteroids onto planets, including earth can send part of that planet into space especially during formation or pre-atmosphere conditions. Its thought even our moon could have been such a result.

    The point of this discussion however is that object was in fact part of this solar system, coming from and made of the same materials that formed our sun and other objects in this system.

    Water/Ice coming from space via Ice/Rock form of asteroids, during formation would have had little resistance from atmosphere and one accepted theory on 'Ocean Formation' suggest that scenario. It would be logical life required elements could have also been involved, however what I have been suggesting is these elements were already here and the same logic would say knowing microscopic micro-isms were (did exist) here 3.5 to 4 billion years ago, then anything that survived from our local space, would simply be additions to the then existence.
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  14. #13 Re: Water and Organics 
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    Quote Originally Posted by jackson33

    Probably the most mis-represented discovery of a meteor, was the 1996 NASA Article on the Allen Hills, Antarctica meteor 'ALH 84001'. Said by them at the time 'The biggest scientific discovery in history'. Thought then to have landed about 13k years ago, from Mars, be about 4 Billion years old and containing some primitive form of microscopic life. It was found in 1984...
    I wasn't refering to the Allan Hills meteorite, which contains magnetite, a compound only made by bacteria on Earth. Nor do I think it is strong evidence for panspermia anyway. (I provided a link to the allan hills article in the life on mars thread yesterday lol.)

    They have found sugars, and many other complex organic molecules in different meteorites, it is nothing remarkable.

    Any evidence of micro-organisms in meteorites has been ambiguous like the Allan Hills meteorite, or have been discounted by paleontologist as pseudofossils.
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    Quote Originally Posted by Cosmo
    bit4 and tired

    I am not an expert in this field, but I assumed that an organism needed
    a fluid medium to live in.

    Cosmo
    Neither am I, I have no proof for my suggestion, it's just something i believed to true, for one reason or another. You're better off listening to i_feel_tiredsleepy. I for one have no idea what a "lithoautotroph" or "hyperthermophiles" is. :P


    i_feel_tiredsleepy: You said life cannot exactly "thrive" in ice, but is it possible that microorganisms (these psychrophiles as you say) could live there permenanlty (or for a prolongued amount of time), perhaps getting water form small pockes of thawed ice, or breaking it up/melting it themselves, by some process or other? What I'm really asking is could "psychrophiles" theoretically survive in a block of asteroid ice for some amount of time?

    I do find the idea of amino acids in asteroids a more sensible idea though.
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    Many of them are adapted to living in high salt concentrations, and others will often contain ice nucleating factors inside them that allow them to freeze without dying. These bacteria tend to be growing and living it up in short periods of temperatures around -5C to 10C, or colder if they are deep ocean organisms. They can definitely survive long periods of being frozen, 1900 year old glacial ice was found to have viable bacteria in it.

    Even more remarkable was that 300,000 year old ice was found to have living bacteria in it. Most of those were spore forming bacteria. It seems that maybe a bacteria could survive the trip through space, but factors like radiation and the high energy impacts make this unlikely. After all these are bacteria that can't survive temperatures of 15-20 C.
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    Thats pretty interesting stuff. when were the 300,000 YO bacteria found? have you got an article about it or anything?
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    Quote Originally Posted by bit4bit
    Thats pretty interesting stuff. when were the 300,000 YO bacteria found? have you got an article about it or anything?
    Here you go http://www.brent.xner.net/pdf%20file...ancientice.pdf, these guys were able to get viable bacteria out of ice dated at >500,000 years old.
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  19. #18  
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    Quote Originally Posted by jackson33
    Unless I am not understanding you, your suggesting life on our planet, could have come from some asteroid, carrying the elements from distant space, not of or from our sun. .
    We have been at minor cross purposes on this one. There is no dispute that 'alien' material was injected into the developing solar system, but this was inorganic. I accept that the origin of life on Earth via pan spermia is disputed.
    Quote Originally Posted by jackson33
    Of the 30k asteroids with calculated orbits, the entire content of the Asteroid belt (between Mars-Jupiter) or the suspected Oort Clouds, outside the limits of our solar gravity, everything is SUSPECTED to be part of our solar formation..
    You are quite forgetting that the sun was almost certainly formed in a star nursery from the collapse of a portion of a much larger GMC (Giant Molecular Cloud). Within that GMC, prior to fragmentation and collapse, there would have been extensive mixing of material, including prebiotic chemicals and plausibly pimitive life.
    Secondly, a significant mass (quite probably much more than half of the orginal disc) of material was ejected from the system during its formation. Many of the comets from the Oort cloud that appraoch the sun are ejected from the system. It is entirely possible (and certain for some of them) that they will end up in another system entirely. Doubtless we benefited from a small influx of such material during solar system formation.

    Quote Originally Posted by i_feel_tiredsleepy
    It seems that maybe a bacteria could survive the trip through space, but factors like radiation and the high energy impacts make this unlikely.
    Naked bacteria cannot, in general, survive the radiation, but you only need a thin layer of rock or ice to protect them.
    Studies have shown that micro-oranisms can survive the energies of impact.
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  20. #19 Re: Water and Organics 
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    Quote Originally Posted by Cosmo
    According to your article above, do you claim that life originates in interstellar space?
    I claim that it is possible that life originates in interstellar space. I claim that there are sound reasons for this hypothesis. I claim that there is good evidence in support of it. I do not claim that this evidence is conclusive. I actually think it is about 50:50 odds on whether life originated in space, or on the Earth. I promote pan spermia and interstellar origin of life because it is, in my opinion, insufficiently considered.
    Quote Originally Posted by Cosmo
    I think life can only originate at temperatures of liquid water from about say 10 degrees Celsius to about 60 degrees Celsius.
    Which temperature is obtained within hot GMCs and within larger planetesimals. Here is an example of the thought process:


    Mautner, M.N. et alOrganic Synthesis and Potential Microbiology in the Solar Nebula: Are Early Solar Systems Nurseries for Microorganisms? Bulletin of the American Astronomical Society 2004 vol 36.

    We observed a new synthetic mechanism that can contribute organics toward the origins of life in the solar nebula. We also observed that microorganisms can grow on carbonaceous asteroid/meteorite materials, suggesting that micoorganisms can multiply in aqueous asteroids in the early Solar System...............
    ............
    The organics in the nebula can contribute to the origins of life and support microorganisms. For example, we observed that microorganisms such as Nocardia asteroides, algae, fungi, and even plant cultures (Asparagus officinalis) grow in planetary microcosms based on carbonaceous chondrite, as well as Martian, meteorites. We found high microbial populations (10exp7 CFU/ml) and complex microbial communities in these planetary microcosms. Thermophilic archaebacteria also grew on these materials.

    The results suggest that early aqueous asteroids can support microorganisms, distribute them through the solar nebula by collisions, deliver them to planets, and possibly eject them to interstellar space.Such natural panspermia processes, or directed panspermia payloads, may seed other young solar systems where microbial life can multiply by similar mechanisms.
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  21. #20  
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    Quote Originally Posted by i_feel_tiredsleepy
    Quote Originally Posted by Cosmo
    bit4 and tired

    I am not an expert in this field, but I assumed that an organism needed
    a fluid medium to live in.

    Cosmo
    Ya, that's why I said ice water, water is needed for them to grow, but some bacteria can survive extended periods of dessication though. Bacteria have been taken from 1000 year old permafrost and were found to still be alive.

    Most cold climate bacteria are lithoautotrophs that live in the microscopic layer of water trapped in rocks or are halophiles that live in pockets of salt water. In Antarctica their are salt water lakes trapped below the ice that are thriving with bacteria, so it is true bacteria can live at extremely cold temperatures, but they still need water to grow.

    After all, if any bacteria/archaea could have made it's way to Earth from let's say Mars, it would have to have been a spore forming cold tolerant bacteria also capable of living in a harsh warm reducing Earth and surviving the intense energy of meteorite impacts, an organism like this simply doesn't exist, nor would it make any evolutionary sense for one to arise.
    Thanks 'sleepy'

    Although I am primarily a cosmologist, your information here would/should be of interest to the biologists.

    I also believe that life could and should be common in our entire universe on the habitable planets.

    Cosmo
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  22. #21 Re: Water and Organics 
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    Quote Originally Posted by Ophiolite
    ............
    The organics in the nebula can contribute to the origins of life and support microorganisms. For example, we observed that microorganisms such as Nocardia asteroides, algae, fungi, and even plant cultures (Asparagus officinalis) grow in planetary microcosms based on carbonaceous chondrite, as well as Martian, meteorites. We found high microbial populations (10exp7 CFU/ml) and complex microbial communities in these planetary microcosms. Thermophilic archaebacteria also grew on these materials.

    The results suggest that early aqueous asteroids can support microorganisms, distribute them through the solar nebula by collisions, deliver them to planets, and possibly eject them to interstellar space.Such natural panspermia processes, or directed panspermia payloads, may seed other young solar systems where microbial life can multiply by similar mechanisms.[/color]
    My issue isn't that you can find an organism that can survive impact, one that can survive space travel, or countless that can live off of meteorites. My issue is that they can't find one that can do all of those. Hyperthermophiles can survive the impact of a meteorite, but they can't survive temperatures as low as 25 C, psychrophiles can survive the trip through space but can't stand high temperatures.

    Moreover, I would be interested in the findings of that article but I couldn't find it in any of the databases I have access to, so I couldn't get to see a full article with the methods and controls used. It was also a little silly of them to grow asparagus because it requires atmospheric oxygen and carbon dioxide to survive, really doesn't offer any information at all lol.
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  23. #22 Re: Water and Organics 
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    Quote Originally Posted by i_feel_tiredsleepy
    My issue isn't that you can find an organism that can survive impact, one that can survive space travel, or countless that can live off of meteorites. My issue is that they can't find one that can do all of those. Hyperthermophiles can survive the impact of a meteorite, but they can't survive temperatures as low as 25 C, psychrophiles can survive the trip through space but can't stand high temperatures.
    These are all good points, but this could reflect the adaptation of these organisms to particular terrestrial environments from an ancestral form that could handle your constraint conditions. Your objections need to be considered, but they do not of themselves rule out the possibility.
    Quote Originally Posted by i_feel_tiredsleepy
    Moreover, I would be interested in the findings of that article but I couldn't find it in any of the databases I have access to, so I couldn't get to see a full article with the methods and controls used.
    Unfortunately this appears to have been
    a poster presented at the 36th DPS Meeting of the AAS, November 2004 within Session 40, Satellite Formation and Origins. Tracking through ADS then the AAS website I wound up with a dead link to http://www.astroecology.com.

    In regard to the asparagus, perhaps they just wished to offer some useful tips. :wink:
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