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Science

Microbes grow in Mars conditions 91

Posted by Hemos from the i-wanna-terraform dept.
Iguana writes "A methane-making, oxygen-hating microbe is able to thrive in Mars-like laboratory conditions, according to a researcher who says the experiment raises fresh hope about the possibility of life on the Red Planet. Check the whole story on MSNBC " "And kids, that the story of how hemos grew cmdrtaco". Oh...er.
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Microbes grow in Mars conditions More

Microbes grow in Mars conditions

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  • Photosynthetic & anaerobic (Score:5)

    by Anonymous Coward on Thursday June 10, 1999 @04:24AM (#1857484)
    Anaerobic organisms have the ability to live without oxygen. Many (perhaps most or all) of them cannot survive in the presence of oxygen. Byproducts of anaerobic metabolism include ethanol and lactic acid. Anaerobic bacteria are not so uncommon. They live in the guts of humans and many other organisms. They also live in many extreme environments such as hot springs, ocean vents, etc.

    Photosynthetic organisms (commons ones, anyway) produce oxygen as a byproduct. They use light energy directly to make their own food molecules. Early photosynthetic organisms were probably also anaerobic, but photosynthetic and anaerobic are distinct concepts.

    Possible evolution:
    1. Anaerobic organisms live and obtain their energy from molecules in their environments.
    2. Some anaerobic organisms gain the ability to photosynthesize, being able to use simpler molecules than their predecessors along with light energy from the sun while producing oxygen as a byproduct.
    3. Oxygen levels increase due to the prosperity of photosynthetic organisms.
    4. Anaerobic organisms die in large numbers as the atmospheric oxygen level rises.
    5. New, more efficient aerobic organisms appear and further the decline of anaerobic organisms.

    Although I cannot currently access my password to log in, I am
    Yet Another Coward
  • Many people would like to study Mars before we completely alter it. Biologists, geologists, certain classes of physicists and meteorologists, among many others, might learn a great deal from Mars. If we slap on some life too soon, we destroy some opportunities to see into Mars' past. If there is life on Mars, the arguments becomes even strong. Competition between earth organisms and Mars organisms could greatly alter both before we can study the Martians.
  • Posted by tha_skunk:

    That is really very cool.

    Let's fly a couple of spaceships packed with
    those microbes to the mars.

    They will start producing methan.
    Once we run out of fuel. We can just fly to Mars.
    compress all that methan they have produced in
    50 years or so and use it as a replacement.

    come on lets do it

    call your senator today
  • Posted by tha_skunk:

    > Can you say "great balls of fire"?

    oh yeah, in case that we solve the energy problem
    before we coulda blow hole mars in pieces, what a
    great firework would this be.

    >I hope you didn't mean the above. Imagine the
    >cost of transporting it

    was not really serious :-)

    But imagine the cost of having no fuel anymore
    and no real alternative for it!!!!!!!!!

    those number coulda make you freak out
  • Posted by tha_skunk:

    Jupiter is virtually a ball of hydrogen. There should be fuel a plenty to burn.

    but also a little bit farer away....

    But a ball of H2!!!!!!!!!!
    Jesus, and I thought a Methanized Mars would be
    a great firework!!!!!!! :-)
  • But I wouldn't want to LIVE there.

    can you imagine how hard it would be just to get something like fresh fruit?

    I'll stay here on Earth, thank you.

    If we can contimplate adjusting Mars' climate, we can contimplate fixing Earth's broken climate too.
    Something I think that is a bit more worthwhile.



    "The number of suckers born each minute doubles every 18 months."
    -jafac's law
  • Yeah, that's the plan. Ship-off all the human inhabitants of Earth (non essential MS employees included) to Mars, and then corner the Oxygen market. Sell it with a per-breath license fee.

    Then, he won't have to worry about Linux anymore.


    "The number of suckers born each minute doubles every 18 months."
    -jafac's law
  • Kim Stanley Robinson. Capsule review: first book great, second book mediocre, third book entirely forgets to have a plot.

    The answer to the question is probably: yes. There's a lot of stuff in the universe, and only a little bit of life. Life is a good thing; spreading it to another planet is too.

    --

  • My understanding is that one of the other problems with conditions on Mars is that with a weak magnetic field and a thin atmosphere, the surface gets bathed in much more harmful-to-life radation than we see here. This experiment doesn't seem to mention that. Am I wrong, or is the experiment missing a major factor?

    --

  • NASA Martian Experiments (Score:3)

    by Hrunting ( 2191 ) on Thursday June 10, 1999 @04:04AM (#1857493) Homepage
    You know, with all the emphasis given to landing stuff on Mars, I'm surprised that I haven't heard any talk of NASA sending these microbes (as well as a variety of life forms that don't qualify as animal -- wouldn't want to enrage the environmentalists, now would we?) in a controlled experiment to the Martian surface. We do our darndest to prove that life could possibly exist on Mars here on Earth, but the best Martian simulation is Mars itself. If we can send a robotic probe to the Martian surface and turn cartwheels in the dust all day, we can certainly set up rudimentary experiments that determine what kinds of lifeforms truly do live in such a harsh environment.

    I hope someone from NASA reads Slashdot and can comment on this. Hopefully, an engineer inside NASA's organization has already thought of this. I can't see why it would be that difficult.
  • They mentioned that there could be trace amounts of liquid water underground on Mars, so I think they were assuming the microbes would live underground, where the water is and where the radiation cannot reach them.

    CP

  • I know...off topic...but how did this anonymous post get a score?

    I personally think this post deserved a score...but I didn't think anon posts were even allowed to get a score.

    <tim<

  • Quote (Score:1)

    by manitee ( 2974 )
    "NASA has been studying the idea of one day sending a methane-producing robot spacecraft to Mars, said Kral."

    That sentence just looks and sounds hillarious.

    In any case, what would the time frame be for methane producing microbes to actually impact the atmosphere on mars? I have to imagine we are talking about thousands (maybe more) of years.

    What we really need is a nitrogen-eating oxygen producing microbe.

    PS: It's too bad these things dont eat methane. I could use some in my girlfriends restroom. ;-)

  • If I'm not mistaken, bacterial life started as anaerobic bacteria (bacteria that procuce oxygen as a byproduct of their metabolism). When there was sufficient oxygen in the atmosphere for it to become toxic to many anaerobic bacteria, aerobic (oxygen-loving) ones evolved.
  • The one thing that many scenarios for terraforming Mars forget is that Mars has no plate tectonics. At first glance that doesn't seem important, but actually it is.

    The oceans of the Earth absorb an amazing amount of CO2 from the atmosphere. In the water that CO2 reacts with the water to form carbonates, which settle on the ocean floor. The carbonates are recycled back into CO2, back into the atmosphere by underwater volcanos along the Atlantic and Pacific ocean ridges. The amount of CO2 that is put back into the atmosphere that way is exactly the same as the amount of CO2 that is absorbed by the oceans.

    A very delicate balance, that didn't, doesn't, and never will exist on Mars. When Mars was young it was probably quite similar to the Earth. Nice and warm. Life might have, and probably did, begin. But the oceans sucked in the CO2, the carbonates settled on the ocean floor, and there were no plate tectonics, no volcanos to recycle those carbonates back into CO2, back into the atmosphere. Slowly but steadily Mars ran out of CO2, the temperatures dropped because the main greenhouse gas was gone, and the planet froze.

    Now what would happen if we terraformed Mars? There'd be liquid oceans again. And again the same problem would arise. CO2 would be absorbed into those oceans, carbonates would settle on the ocean floor, and eventually Mars would again freeze up. Sure, then you could terraform again, or you could introduce other greenhouse gasses to keep Mars' temperature elevated, but eventually you wouldn't be able to keep up.

    The balance on Earth is so delicate that even a small change can screw up the climates all around the globe. Mars is completely different, it'll have a completely different balance.

    Venus, Terra and Mars all started alike. Venus' greenhouse effect got completely out of control and the planet heated up, probably even before life could form. Mars' greenhouse effect screwed up aswell, and the planet froze up before any complex life could form. Terra is right inbetween. A delicate balance that becomes upset after only minute changes. A delicate balance that imho is doomed to fail if attempted on any other planet.

    Terraforming mars is nice stuff for fiction, but I'm convinced it will never happen. And if it does, it probably won't last for more than a few hundred or maybe a few thousand years.


    )O(
    the Gods have a sense of humor,
  • CO2 isn't just needed for the greenhouse effect. It's also a necessity for plant life. Without not enough CO2 plants will not be able to create enough oxygen. And also, keeping CO2 production high? How? We're talking about an annual production of CO2 that rivals, if not surpasses that of all the Earth's industry and transportation combined.

    And yes, terraforming Mars will be a long, slow and boring process :-)


    )O(
    the Gods have a sense of humor,
  • I assume you mean the Earth is inbetween Venus and Mars astrometrically aswell. That indeed has an influence on the greenhouse effect in that the Earth gets 2.68 times more solar radiation than Mars, and Venus gets 1.95 times more solar radiation than the Earth (5.22 times more than Mars). But there is also the issue of atmosphere. The Earth's atmosphere for example holds back a lot of solar radiation.

    What caused Venus' greenhouse effect to topple is probably the high solar radiation. But what caused Mars' greenhouse effect to topple the other way is not as much the low solar radiation, but more the lack of plate tectonics.


    )O(
    the Gods have a sense of humor,
  • There's always the Brute Force and Ignorance approach: Mine the limestone back off the ocean floor and break it down into calcium oxide and carbon dioxide again. This would take a fair amount of industry, but if we have the wherewithal to terraform a _planet_, this should be do-able (if we want to).

    I hadn't thought of that... It is indeed a possibility, though horribly expensive. But, since terraforming Mars will take hundreds of years to complete with whatever method you use, there'll probably be effective ways to mine the sea bed by then.

    My big caveat isn't the fact that terraforming a planet is horrifically expensive, more that it takes horrifically long. Many generations would pass before the project is finished. I still have to find the first person who is willing to pay billions and billions of dollars so his great great great great grandchildren can move to Mars. :-)


    )O(
    the Gods have a sense of humor,
  • where are the moderators when you need them? :-)

    I had never heard of that... anybody know any online sources on terraforming Venus? Venus is indeed only a fraction smaller than the Earth, so if it could be terraformed, it would be a perfect Terra II. And Venus is closer than Mars too... Strange that something so obvious is completely overlooked due to the Mars Craze...


    )O(
    the Gods have a sense of humor,

  • Re:Radiation? (Score:3)

    by Chakotay ( 3529 ) <a DOT arendsen AT gmail DOT com> on Thursday June 10, 1999 @03:56AM (#1857503) Homepage
    Mars is also 1.637 times farther away from the sun, so it gets only 0.373 times the solar radiation as Terra here gets. Ultra violet solar radiation is probably still quite a big problem on Mars. And even though Mars is a lot farther away, solar winds might also provide a big problem. Due to its proximity to the Asteroid Belt it's also more likely to be hit by a big piece of space junk. Actually, Antarctica and the Sahara are hundreds of times more hospitable to human life than Mars.

    But then again, in the place that is the most inhospitable to human life here on Earth, in the depths of the oceans, there is life, completely independent from the sun. Actually I think the chance of finding life on Europa are larger than the chance of finding life on Mars. Mars' climate is unlike that anywhere on earth. Below Europa's icey surface are liquid oceans, melted by its volcanos; an environment quite similar to the depths of the Earth's oceans; an environment quite similar to the environment many scientists believe spawned the first life on Earth.


    )O(
    the Gods have a sense of humor,
  • (probably not a new Idea, but what the hell)

    Seed the universe with life. Lets say intelligent life evolved somewhere (not necessarily Earth). They get lonely. Being the patient species that they are, the figure that they only way to get some company is to make some.

    So: They load up a few zillion asteriods with a variety of different microbes, each type tailored to survive in a particular environment. Having sc attered these asteroids throughout the known universe, they sit back and wait for something "interesting" to evolve (say a billion years, give or take).

    The universe isn't so lonely any more.
  • I don't think I've ever heard of any group taking up for the rights of bacteria.

    "Penicillin must be stopped. End the killing now!"

    Genetic modification is a different matter, but I think you get the idea.
  • Hey, you got that idea from 2010.

    "All these worlds are yours, except Europa. Attempt no landings there."

    Life on Europa, as intriguing as it seems, hasn't been around long and won't be around longer. Almost all the heat out there is caused by volcanic activity on the moon; as its not very big, chances are that heat won't last very long.

  • Combustion is the combination of a substance with oxygen, by definition. Since mars has almost no oxygen around, there's not much chance of any burning at all. Your match would spark, but it wouldn't burn because there's no O2 to fuel it.

    It's the same reason why Jupiter (a big ball of hydrogen (and some other gasses) with tremendous electrical storms beneath the "surface") hasn't exploded lately. H2 combines swell with 02, but if there's no 02 around, no fire.

  • if we were to send microbes to mars that would pretty much destroy any chance of seeing if there was life native to mars. while it would be cool to terraform mars, it would also be cool to study what mars is on its own before we "embrace and extend" it.
  • And what was the atmospheric pressure in his experiments?
    Christopher A. Bohn
  • "NASA has been studying the idea of one day sending a methane-producing robot spacecraft to Mars, said Kral."

    But not to release it into the atmosphere -- this idea is to produce rocket fuel from indigineous resources ("live off the land") and store it for use by a return-sample mission that will arrive two years later.
    Christopher A. Bohn
  • Although I do work for NASA, do not take what I say here as anything even remotely resembling official NASA policy or opinion.

    Having said that, I think that it's very unlikely that NASA will send any microbes to Mars. To quote David Dubov concerning the Mars Pathfinder [nasa.gov]:

    There are internationally accepted guidelines that NASA has adopted as rules that govern the number and distribution of Earth "spores" (bacteria or other biological contaminate) that we can sprinkle (intentionlly or otherwise) on the surface of another planet (or moon) believed to have had the potential of harboring life in the past or present.

    The two Viking landers were sterilized in a large oven and then encapsulated just before they were rocketed to Mars. This means that there were minimal concerns about the spacecraft inadvertantly crashing onto the Martian surface and spraying Earth spores everywhere. Baking the Viking spacecraft was considered very controversial in its day however. The builders were very concerned that the high temperatures would damage or degrade the materials used in the construction. On Pathfinder we were very reluctant to bake the whole spacecraft. Instead, we opted for baking bits and pieces (low gain antenna, parachute, etc.), and cleaning the rest (wiping or immersing in cleaning solvents).

    The end result is that the outside of Pathfinder is clean to within the allotment set by the international guidelines (we know this because we were continously taking bio-assays to count the bugs). But what if we inadvertantly put it onto a collision course with Mars and then somehow lost control of the spacecraft? Wouldn't the Earth-bacteria sealed on the inside escape onto the surface when it crash landed?

    We don't know, but we could avoid the issue altogether by putting the spacecraft on a collision course in the first place. By keeping the trajectory near the edge (limb) of Mars we could make sure that, if the spacecraft is lost control of, either it misses Mars altogether, or crash lands with a velocity slow enough so it doesn't spew the bugs all over the surface. Of course, this won't happen!

  • Imagine putting a match to that!
    --
  • Yeap that's quite cool. Microbes... Three years ago NASA made some fuss about microbes from Mars. It got so burned up that forgot completely about the matter.
    Now it is thinking on making a missionary mission. With microbes. Ok don't forget to send the Bible with them.
    Lyrics...
    Maybe NASA should have always take for serious its own "case for the Face". At least it would have got a loot of publicity. Or search for li'll green men. Then it would never quit newspapers last page.
    Yeap it is time for NASA to turn into a masonic house. Every night a session of shamanism... Hoagland will not loose his job for the next 100 years...

    PS: One of you guys was talking about the "lack" of plate tectonics in Mars. Mars had them. There are several relicts of it in Mars. Recently NASA
    added some fire to this on publishing the results of Surveyor's geomagnetic data. Do not get surprised by this positive note on NASA. That thing is not an organisation. It is a battlefield. Unfortunately the dodos are on some of the tops of it...
  • I'm assuming that the experiment was conducted above the freezing point of water at whatever pressure they chose. How deep into the Martian surface does one have to go to be permanently above freezing? (I know, I know; it depends on where you are on Mars.)

    BTW, imagine a Beowulf cluster of Martian methanogens. Sorry.
  • Now what would happen if we terraformed Mars? There'd be liquid oceans again. And again the same problem would arise. CO2 would be absorbed into those oceans, carbonates would settle on the ocean floor, and eventually Mars would again freeze up. Sure, then you could terraform again, or you could introduce other greenhouse gasses to keep Mars' temperature elevated, but eventually you wouldn't be able to keep up.


    There's always the Brute Force and Ignorance approach: Mine the limestone back off the ocean floor and break it down into calcium oxide and carbon dioxide again. This would take a fair amount of industry, but if we have the wherewithal to terraform a _planet_, this should be do-able (if we want to).


    The last is a big caveat. Terraforming will be horriffically expensive. Either we'd need an extremely good reason to terraform, or the cost would have to drop a *lot* before we would do so.

  • I can understand what your saying. It does put a damper on complex life that has evolved how we have from existing on mars But who says that all complex life has to breath oxygen?
  • I wonder if those who want to terraform Mars have forgotten why Mars is in its current situation. Mars doesn't have the requisite gravity to hold liquid/gaseous water or any significant atmosphere. So, if we were to terraform Mars we would exhaust all of its water and atmospheric resources in a few hundred years leaving a dry stripped rock in our wake. I would hope our entry into colonizing the universe could be a little more considerate of our surroundings.

    Maybe we could just colonize the planet using domes and other resource conservation techniques and have an outpost for a good long time.

    Just call me an interplanetary tree hugger!

  • ...We'll stripmine the rest of the planets later"
  • So, assuming these little critters can (be adapted to) survive and prosper in the Martian atmosphere, what effect will bumping up Methane levels have on Greenhouse-type effects?

    If it has a warming effect, would it (eventually) rise enough to thaw any liquid water near the surface?
  • Whole last paragraph answered my first question.
  • Unless you're talking about satelites, which beam the energy down to earth (And you thought the powerline-cancer scare was bad....) I suggest you look a little deeper...

  • Re:been reading your Arthur C. Clarke (Score:3)

    by coreybrenner ( 19101 ) on Thursday June 10, 1999 @11:33AM (#1857523)
    Actually, he probably got this idea from reading the works of Richard C. Hoagland, who was the first to come forth with credible evidence of liquid water beneath the surface of Europa.

    The heat that could keep the system going would, indeed, be caused by vulcanism. However, it is doubtful that that volcanic activity will ever cease. Consider that Europa is probably about the same age as the Earth, and is at least hypothetically volcanically active. This volcanic activity would be caused by the gravitational forces of Jupiter and the other moons, and isn't likely to change (unless something rather drastic happens in the vicinity of Jupiter).

    Io, another of Jupiter's moons, is visibly volcanically active (probably the most active body in the whole solar system). It is and will remain very hot because of the gravitation of Jupiter.

    So, if Europa is currently volcanically active (a likely hypothesis, given the gravitational oomph of Jupiter), and has a big bunch of water ice (we believe we've observed this), and has liquid water beneath an icy crust (another likely hypothesis, given the heat that must be at the core of that little moon), then assuming that some kind of life could have organized itself there, and could have evolved to the point where it can survive in the water (which must be quite toxic, at least by our standards, by now, though what is garbage to us might well be rich nutrition to some little beasties on Europa), then it's a good possibility that life exists there to this day.

    --Corey
  • Sure we're doing it now and here but we're still literally light years away.

    Actually, you're not that far from Mars. It might take light a second or two to get from here to Mars. In stellar circles, that's just blinking.

    Just trying to keep things in perspective. :)
    jaz

  • Ok, sent the link to my pops and brother, both peeaichdee chemists.
    Here's my dad's response, pretty much verbatim. Enjoy knowing the truth, ya'll.
    jaz Beez,

    (Arrgh...) There were only a few howlers in that Mars story. A major one, though, is the suggestion that bacterial methane might "power" a Mars colony in an atmosphere that contains "no" oxygen. (Whatcha gonna burn it with?) Actually the martian atmosphere doesn't have "no" oxygen, but it's a little scarce: something like 0.1% if I remember right, which is actually enough for a pretty high redox potential, but not a good bet as a fuel burner. Also, in spite of the subhead, the bugs don't "make hydrogen and nitrogen" - which requires Big Bang/ stellar core conditions respectively - nor could they possibly "use hydrogen and nitrogen to make methane" without the intervention of alchemy.

    I'd be more impressed about the "martian conditions" if their petrie dishes had been bathed in UV and whiffed with ozone, hydrogen peroxide, and OH radicals like actual martian soil (that's why it has no organics left) and held at 200 - 250 K temperatures.

    Finally, they're going to have trouble with that methane-powered rocket back to Earth without an oxidizer. Of course, they could use (faint) solar power to make oxygen out of (scarce) water, - but then why not just use the hydrogen from that as fuel instead of methane?

    All of which is not to say that I don't love the breakthrough news. But you gotta watch that MSNBC. Would you trust them for news of a new PC virus?

    Love -
    Dad

  • In our AstroPhysics class (taught by a guy with a Nobel Prize) we had a real lengthy discussion about terraforming Mars. Basically, Mars is spinning too fast and is too far (or maybe close, I don't remember exactly) to the sun for it to actually be able to hold water vapor. Mars needs to be warmed up (or cooled down, its been 2 years since the class) and slowed down before an atmosphere with water vapor can exist.

  • In the article it says that faint traces of water in the soil are assumed. Isn't that most of the problem? That mars is a dry planet? Also, there is some oxygen in the atmosphere of Mars. It seems unlikely that, given previous evidence of amino acids (but not DNA or RNA) in meterorites, there could be a form of life on Earth which wouldn't need substantial changes in its system to survive on Mars.

    Scientific American [scientificamerican.com] has some information on this.

    -Ben Shniper

  • Now what would happen if we terraformed Mars? There'd be liquid oceans again. And again the same problem would arise. CO2 would be absorbed into those oceans, carbonates would settle on the ocean floor, and eventually Mars would again freeze up. Sure, then you could terraform again, or you could introduce other greenhouse gasses to keep Mars' temperature elevated, but eventually you wouldn't be able to keep up.

    So you find, breed, or genetically engineer organisms that convert the carbonates back into CO2, and set it loose on the bottom of your oceans.


    --

  • This makes me so mad (Score:3)

    by DonkPunch ( 30957 ) on Thursday June 10, 1999 @05:55AM (#1857529) Homepage Journal
    Why do they have to get involved in everything? Geez, isn't it enough that they dominate down here on earth? Now they have to spread to Mars!

    Oh, wait.... Microbes.... I thought it said "Microsoft".

    Never mind.
  • The article really talks about there could be life on Mars...
    but if there was life on Mars, and we can't survive in that environment, would we want to?
  • Sounds much like the Red/Green/Blue Mars series of books that I have read (can't remember the author dammit!). Terraforming with microbes.
    This idea isn't too new. Like many things that have since happened (such as Arthur C Clarke's prophecy of a network of satellites), I'm sure this terraforming of Mars will happen in the future.
    Now the question is: Do we really want to terraform Mars ?
  • From what I understand anonymous posts start out with a score of 0, but can be raised. Non-anonymous posts start at 1.

    Although I could be mistaken.
  • energy. Do what some people do. Call Oil CEOs at 4:00 in the morning and bitch in 40 different languages.
  • Nitrogenase dude..N2 -> ammonia, room temperature, 1 atm. It's a miracle of evolution ;)

  • Exobiology (Score:3)

    by Invicta{HOG} ( 38763 ) on Thursday June 10, 1999 @10:24PM (#1857535)
    Although I'm no expert on the subject and all real questions should be asked of Dr. Kral himself, I do have a passing familiarity with his experiments after certain lectures he gave in my micro class (I attend the University of Arkansas and had him for class this past year).

    He is really not trying to say anything special about this experiment; his happens to be a field which excites the imagination and draws popular attention. As such, I think that many of the quotes he has are the result of a request to speculate...

    Anyway, his experiment was simply to grow microorganisms in a fairly hostile environment which approximates many of the things that we know about current conditions on Mars. He used volcanic ash which is believed to resemble Martian soil. No temperature or pressure differences were attempted in the first run because little is known about below Mars below the surface. Indeed, the surface is too cold for liquid water (apparently around -200C) and higher temperatures must be assumed if life (as we currently understand it) currently exists on Mars. There are plans for a range of growth conditions which include harsher temperatures and pressures (as far as I know, no one has been able to grow microbes in the experimental conditions, let alone less hospitable ones).

    As far as radiation goes, both ionizing and non-ionizing forms are incident on the surface of Mars. However, at subsurface depths there is little reason to think that the intensities will remain the same, especially for non-ionizing (such as UV) forms. Since this is the environment which is to be modeled, radiation was ignored.

    Questions about nitrogen appear to stem from a misunderstanding, perhaps, of the metabolism of Archaebacteria. These bacteria are believed by many to be ancestral to the more accessible bacteria which abound on earth and in textbooks. Methanogens, from a very basic understanding that I have, can use a variety of molecules to provide the reducing power necessary to produce biologically accessible forms of energy and, as a result, biologically useful molecules. I know
    that NO3 is used but am less sure about pure nitrogen. I am not sure that the researchers themselves know the specific nitrogen source the microbes utilized, but it is believed that the nitrogen content of the experimental medium was ~1%, less than the 3% believed to be present in the Martian atmosphere. In any event, the microbes do not tolerate oxygen (it forms radicals which the cell cannot handle) and it is thought that, esp. given the low level of atmospheric oxygen, subsurface levels of O2 would be conducive to cell growth.

    Finally, as to previous proof of life on Mars (esp. the ALH001 meteorite), recent research has cast doubt on Zare, et. al's hypotheses. In fact, this past year Dr. Kral coauthored a paper which suggested that similar chemical patterns could be identified on rocks taken from the moon. Because the moon is such an unlikely candidate for life, the meteorite evidence shouldn't stand on its own as proof of life anywhere.

    This all just goes to say that no one will really know anything for certain about life on Mars until some redneck terraformer comes down with a cold...

    Sources for this post come from the university press release:

    http://PIGTRAIL.UARK.EDU/NEWS/june99/ mars_life.html [uark.edu]

    Sears D. W. G. and Kral T. A. (1998) Martian "microfossils" in lunar meteorites? Meteoritics and Planetary Science 33, 791-794,

    and correspondence with members of the research group. All information presented herein represent the (somewhat poor) understanding of an
    unrelated party (me!) and do not represent the actual researchers' beliefs or opinions.

    Invicta{HOG}
  • Coincidently, Terra happens to be between Venus and Mars in another important way... Or, I should say, your analysis implies that it is merely coincidental.
  • The author is Kim Stanley Robinson.
    Great Series. I bought it as a set and killed about 3 weeks of vacation time last summer.
  • That's supposed to raise hope that primitive life may exist on the Red Planet? Heh. :)

    I think it makes it sound as if the Red Planet is even more hostile to complex life than we imagine. Still, if microbes are able to thrive there, it doesn't mean they have.

    "There is no surer way to ruin a good discussion than to contaminate it with the facts."

  • Re:Radiation? (Score:3)

    by RimRod ( 57834 ) on Thursday June 10, 1999 @03:45AM (#1857539)
    You're absolutely correct. The article doesn't explicitly mention whether radiation and other non-atmospheric conditions were taken into account. Hopefully it just didn't make it into the layman's terms version of the research summary.

    Another important thing to think about (and I hope that people don't draw this conclusion) is that just because we've found something that could _conceiveably_ survive on Mars, it doesn't mean that it or anything like it ever did. I only mention this because the header of the /. post is somewhat misleading ("...raises the possibility of life on the Red Planet"). The article mentions nothing of actual life on Mars, past or present. The main focus, in fact, seems to be transplanting this earth-made organism _to_ Mars in order to create methane and change the climate somewhat (to facilitate human colonization).
  • *Many* years ago, a college friend, whose father worked in the space program, speculated the sterilization for the Viking mission was done with an early 1970's understanding of bacteria and virii. He thought virii like the Epstein-Barr virus might have withstood the 1970's NASA sterilization procedure, since the hardiness of such bugs wasn't widely understood and appreciated at the time. And it is exactly those hardy bugs that could withstand the rigors of sterilization and space travel, and thus would be able to survive on the surface of Mars.

    Not a Good Thing.

    I'm wholly unburdened with technical knowledge in the area, but I suspect we know less than we think...first, do no harm.
  • Hello, My name is Curtis Bekkum, I did most of the research for Dr. Kral on this subject. Let me try to answer some questions about our research. First of all, we did not find life on Mars.... yet. All we did was to take Martian soil simulant that was void of a carbon source and add varying amounts of water and detected growth by methane production. We wanted to show that the soil, if it has water and the water was liquid, then life could have and can flourish there.
    Everyone thinks we tried to copy the conditions on the surface of Mars, But life can grow underground. On Earth there was a discovery a few years back that bacteris existed in granite aquifers two miles below the surface. So if Mars is like earth and there is liquid water underground, then there,theoretically, could be life. Water is the key, and according to our results not that much water only about 0.5 ml per 5g of soil. Radiation would not be a factor since the organisms would be subterranian. Also methanogens use Hydrogen and Carbon Dioxide to make methane, this is it's chemoautotrophic mechanism to make energy. Nitrogen would be used to make amino acids and other compounds.
    The atmosphere of Mars is about 1/100th of that on earth, it is composed of CO2, N2, and CO. Some archea bacteria can exist only on CO and water. Also again subterranian water could have dissovled gases, such as hydrogen from various chemical and/or volcanic sources. As evidence I refer you to the above topic of granite aquifers. Also volcanic plums in deepsea vents harbor bacteria.
    So as conditions are now, life cannot exist on the surface of mars, too cold, not enough water, oxidation, radiation, ect. But it could have existed at one point, and it still could exist today under ground.

    Any other Questions can be asked to me, my email is cbekkum@comp.uark.edu

    Thanks, and i hope i answered at least some of your questions.
  • Discovery Channel had a show on microbes that exist at the bottom of the ocean, next to super hot vents. They also took core samples from pretty far down in the earth (technical??, sorry, I don't have the details). These microbes breath iron. He showed a jar of iron and another that the microbes ate. It was a jar of magnetite...
    They(Discovery ch.) suggested that this microbe could survive in outerspace with a sufficent supply of iron.

    ...when the mars probe data came back, there was a very small blurb on an excessive amount of magnetism, I beleive I read magnetite. Next probe needs to test for signs of this microbe. Anybody see a picture of the hugh crater on the other side of Mars??? if this microbe needs a carrier, that sucker would've been large enough.

    LIFE ON MARS !!!!! ...cool
  • So lets see, if i can just work out how to reinvent myself as a methane-making, oxygen-hating microbe there's fresh hope for me... Back to the lab to see what's on the slab.

    This isn't such groundbreaking news, NASA have been aware of the existence of microbes on Mars since August 1996 when scientists publically announced that an ancient meteorite that had plunged to Earth from Mars and revealed signs of primitive life. Astronomer Donald Goldsmith published a book detailing microbe findings which were traced from the rock remnants.

    Sure we're doing it now and here but we're still literally light years away.


  • That's the critical question here. It doesn't mean a helluva lot to say you've achieved microbial growth under 'Mars-like' conditions without putting the whole concoction thru -60C temperature. It's not particularly surprising to see microbes surviving in a methane-rich atmosphere, as many scientists already believe that this was the environment in which microbes emerged during our own planet's history.

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