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Mars NASA Space

New Evidence For Ancient Life On Mars 186

Posted by kdawson
from the martian-overlords dept.
siddesu writes in with "compelling" new data that chemical and fossil evidence of ancient microbial life on Mars was carried to Earth in a Martian meteorite. The finding is being highlighted by the same NASA team who made the initial discovery 13 years ago. Spaceflight Now has more details of the analysis.
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New Evidence For Ancient Life On Mars

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  • Well (Score:3, Insightful)

    by Dunbal (464142) on Friday November 27, 2009 @07:04PM (#30250288)

    This would certainly widen the belt for what we consider to be the "habitable" range, in our search for habitable exoplanets.

  • Re:Panspermia (Score:5, Insightful)

    by danlip (737336) on Friday November 27, 2009 @07:22PM (#30250492)

    I'm rooting for independent evolution. It would make it far more likely that the universe is teaming with life. But unless we find current life on Mars, it may be hard to tell the difference.

  • Re:Mars origin (Score:3, Insightful)

    by Anonymous Coward on Friday November 27, 2009 @07:24PM (#30250500)

    Can someone explain to me why the set of meteorites are considered more likely to have originated on Mars than from an impact on Earth itself?

    Are there Earth-origin ones known to distinguish them from, since debris from such an earth impact would more likely have orbits intersecting earth's, or is some other evidence used? I'm having trouble finding it.

    Got to actually read the articles. They explain the traces of atmosphere match Mars not the Earth. A number of other Mars meteors have been identified. The article even mentions two others with the same structures. Lots of good info if you read the articles. Once people throw in the towel and accept that there was or is life on Mars then the argument will be did it evolve there and is it part of the same evolutionary cycle as Earth? Those are the fights that will likely take decades and there may never be a clear answer. It's a massive question because if it did evolve independently then anywhere life could evolve it probably has evolved meaning there are millions of planets with life just in our Galaxy. I think within the next 20 years there will be a resolution to the question of life based on direct sampling but the second question of it's source will be a fight to the bitter end.

  • by cefek (148764) on Friday November 27, 2009 @07:28PM (#30250546)

    It is our genes that push our kind to the Space, and it is our genes that are calling home. Wonderful thing that somewhere in our DNA strands lies our extraterrestial legacy.

    It could be the nature that put us here. It must be our civilizational effort to get outta here... before we shred this planet to pieces.

  • Re:Panspermia (Score:5, Insightful)

    by Anonymous Coward on Friday November 27, 2009 @07:30PM (#30250556)

    Either case means the same thing, that life can travel and spread. It takes millions of years for a rock from mars to reach earth, and vice versa. If life can survive that journey, why couldn't it survive in some small way between stars, over billions of years.

    If life once existed on Mars, it will exist now. It is highly unlikely the entire planet became 100% sterile. There will be pockets of life surviving the harsh climate.

    The big question is exploration of Mars. If life evolved independently, we will have a much harder time mucking around there, especially colonizing it. Folks will want to leave it alone to its own devices. It life on Mars and life on Earth share a common history, it makes it much easier to muck around on Mars, because it'll just be another extension of life here so no worry about contamination.

  • by Beelzebud (1361137) on Friday November 27, 2009 @07:47PM (#30250748)
    It's a 9 month journey to mars, and 9 months back. I don't think we'll need warp drives for that. The only thing that stops us is the will to do it.
  • by ianare (1132971) on Friday November 27, 2009 @07:54PM (#30250830)

    If it wasn't for the spacecrafts sent to Mars, it would not have been possible to identify the meteorite as coming from Mars. From the article : "Scientists were able to trace the meteorite back to Mars, as its chemical composition matched the relative proportions of various gases measured in observations of the atmosphere of Mars made by the Viking spacecraft in the 1970s."

    As for the rovers sent later, they were not sent to investigate life but mainly to study the geology and climate.

  • by cameigons (1617181) on Friday November 27, 2009 @08:21PM (#30251086)
    There's a whole lot of people with lots of will and wits to do it. It's just that the 'money people' doesn't seem to be an expressive crowd among them, and the government thinks it's better to spend our taxpayer's money giving it away to banks or killing and starving already dirt-poor people in the middle east. Also, It all sounds very exciting when some promising report such as this one comes out on the media. But there's a few engineering and life-sustaining problems to be overcome so the trip becomes reality, and research in that area is more often than not preceded by years of seemingly(or 'from a business perspective') fruitless research. Imo, that seems to have driven some potential investors away.
  • by Beelzebud (1361137) on Friday November 27, 2009 @08:38PM (#30251268)
    Well that's sort of what I meant by the "will to do it". The people that can green light a project like that, won't, because of political fear, and short-sightedness.
  • by cameigons (1617181) on Friday November 27, 2009 @08:40PM (#30251274)

    More seriously, even with chemical propulsion, the worst case, you can get to Mars in about six months. Sure it's a hard problem, but that's all that it is. There's nothing impossible about getting to Mars. It would be nice to have some far faster means of getting there, but it's not necessary.

    But, considering that's the way to go, can you estimate how much would that cost to assemble,test, launch, deploy, etc? Would the astronauts have canned food for a year or would have some sort of greenhouse to grow their own? Can they carry the necessary amount of fuel to be used in the years they'll spent on the trip? How much would the payload be.... How exactly would they avoid the martian windstorms(this might pose a problem specially to the launch back to Earth) and extreme temperature variations.. I'm just saying, we can't overlook the "details".

  • Re:Panspermia (Score:3, Insightful)

    by Walkingshark (711886) on Friday November 27, 2009 @09:25PM (#30251568) Homepage

    If your hypothesis is right, then any other earthlike planets are also spewing bacterial spores into deep space, which means that life all over the galaxy should be pretty similar.

    So maybe the aliens really will be coming to eat us.

  • Re:Panspermia (Score:5, Insightful)

    by c6gunner (950153) on Friday November 27, 2009 @09:31PM (#30251598)

    Either case means the same thing, that life can travel and spread

    No, they don't mean the same thing. If life began once and was seeded via meteorites, then it's a giant crap-shoot, and the vast majority of solar-systems are probably sterile. On the other hand, if abiogenesis took place twice in a single solar system, then the universe is probably teeming with life.

    If life evolved independently, we will have a much harder time mucking around there, especially colonizing it. Folks will want to leave it alone to its own devices.

    Hardly. It might raise some ethical conundrums, but it certainly won't make colonization any more difficult.

    If we ever colonize mars, we're going to start by building habitats. We'll have hundreds of years to live on a planet which we haven't even begun to terraform. That will give us plenty of time to have the People for the Ethical Treatment of Martian Lifeforms present a convincing case for why we should abandon an entire planet to a bunch of alien microbes. If they fail in convincing the rest of humanity, then we'll carry on with our terraforming effort, and the Martian bacteria will be relegated to sample jars, museums, and computer databases.

  • Re:Panspermia (Score:5, Insightful)

    by Tablizer (95088) on Friday November 27, 2009 @10:24PM (#30251878) Homepage Journal

    Actually, astronomers figured it out a few decades ago. They concluded that, while the Mars -> Earth trip is difficult and unlikely, the other direction has happened with probability around 0.999999....

    Mars-to-Earth is 100% because we found a dozen or so meteorites from Mars, proving it happens. (Kudos to Viking Landers for the chem analysis to compare.)

    Because of Earth's size compared to Mars, Earth was still a hot coal when Mars was almost like Earth today, with mild temperatures, relatively thick atmosphere, and lakes, possibly even oceans. Thus, life is more likely to have had evolved on Mars early in the solar system's history than Earth, if it was around then. Mars was the happening club in town back in the days.
       

  • Re:Panspermia (Score:2, Insightful)

    by Hammer79 (1163799) on Friday November 27, 2009 @10:56PM (#30252030)
    If the Earth is leaving a dust & bacteria trail behind, the dust would still be caught in orbit around the Sun. The dust would orbit the galaxies core at the same speed as the Sun unless it was forced out the Sun's orbit by something else.
  • Re:Panspermia (Score:3, Insightful)

    by jc42 (318812) on Saturday November 28, 2009 @12:22AM (#30252414) Homepage Journal

    Yeah, Jupiter would be a sinkhole for a lot of the debris being pushed out by the solar wind. But it's not all that effective. After all, Earth has a couple hundred recognizable impact craters, things the Jupiter wasn't able to grab. Astronomers have also been able to measure the smaller incoming particles, and they amount to several tons per day. (I wonder whether this is more or less than the loss via the dust tail. Anyone know the numbers?)

    I've seen a few references to an astronomer's comment that the Solar System is the sun, Jupiter, and a lot of insignificant rubble. I've also seen a suggestion that this could turn out true for living things, too. Of course, the sun would tend to dissociate the molecules of any living thing that falls into it, unless there's "life" that exists in a plasma state. But if you look at the chemical constituents of Jupiter's atmosphere, it does look a lot like a huge biochechemical reactor system. Lots of yummy molecules with C, H, O, N and trace elements. It just might turn out that most of the life in the Solar System is inside Jupiter are various depths. It may be a while before we have a good Jupiter Explorer bot, though. There aren't any Earth-like conditions there anywhere.

  • Re:Panspermia (Score:1, Insightful)

    by Anonymous Coward on Saturday November 28, 2009 @01:11AM (#30252604)

    the likelihood that alien lifeforms will have a genetic coding that is structured the same way as DNA or RNA is slim, but possible

    Citation please?

    What if the following two statements are true? 1> Only nucleotides as we know them can form life, and 2> Life emerges independently throughout the universe.

    I'm just saying, no two different molecules have identical properties, even versions with opposing chirality. It could be the case that the nucleotides we know are the only way life can work, even to the point that DNA might have to twist the same way! And, it could be that nucleotides that we know are created randomly everywhere, meaning life can spring up everywhere in the universe.

    I actually find that easier to believe than to believe that Earth and the life on it is something unique.

  • Re:Panspermia (Score:3, Insightful)

    by Solandri (704621) on Saturday November 28, 2009 @02:26AM (#30252864)

    Hardly. It might raise some ethical conundrums, but it certainly won't make colonization any more difficult.

    If we ever colonize mars, we're going to start by building habitats. We'll have hundreds of years to live on a planet which we haven't even begun to terraform. That will give us plenty of time to have the People for the Ethical Treatment of Martian Lifeforms present a convincing case for why we should abandon an entire planet to a bunch of alien microbes. If they fail in convincing the rest of humanity, then we'll carry on with our terraforming effort, and the Martian bacteria will be relegated to sample jars, museums, and computer databases.

    Yeah, that sounds great if you're the one doing the terraforming. I suppose you'll have no problem when the Vogons come by to eliminate Earth to make room for a hyperspace bypass, relegating all of Earth to a computer database entry of "Mostly harmless"?

  • Re:Panspermia (Score:3, Insightful)

    by greyhueofdoubt (1159527) on Saturday November 28, 2009 @01:46PM (#30255500) Homepage Journal

    Eh, I have to disagree on that point. It has historically gone more like this:

    -microbe evolves side by side with a human (or close human relative) population; the humans build up defenses against that particular microbe

    Then either:
    -Something changes (environment, nutrition, domestic animals, etc.) that tips the scales in one direction or the other, giving you a plague or a reduction in disease
    -A previously unexposed group of humans encounters the microbe; the microbe has evolved to deal with human defenses, these humans don't have the defenses, bam, you got yourself a plague.

    I have yet to hear of a real human-killing pathogen that just appeared out of nowhere. HIV, for instance, crossed over from our close ape or monkey relatives. Rabies is another one. Anthrax, certain flues, many parasites. My point is that it's very unlikely that life on mars would be deadly to us as an infectious agent because it had spent millions of years focusing on surviving heat, cold, radiation, drought or flood, etc.- and most importantly, there are no food sources that even remotely resemble warm-blooded animals on mars. So the microbes would have to make an evolutionary leap from eating iron, sulfur, or other inorganic substance to dealing with the intricate and extraordinarily hostile environment of a human body.

    I'm really not worried about it. There are so many other difficulties to overcome that by the time we actually send people to mars, I'm sure we'll have a pretty good picture of what kind of life, if any, exists there.

    -b

  • Re:Panspermia (Score:3, Insightful)

    by danlip (737336) on Saturday November 28, 2009 @03:04PM (#30255966)

    RNA probably came before DNA, and some life uses only RNA (some viruses for example). DNA is not just 2 RNAs put together, there are substantial differences. So even on earth there are 2 different solutions to the basic problem. Even keeping the basic structure of DNA/RNA there are probably lots of ways to hang a few extra atoms of the bases to create completely different bases (which would then need different transcription enzymes, etc.). And I still wouldn't rule out a completely different structure, since there are so many ways to link carbons together to form complex structures.

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