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Mars Space

Rover Exiting Crater To Continue Martian Marathon 150

Riding with Robots writes "The robotic geologist Opportunity has nearly reached the rim of Victoria Crater, which it is leaving after a year of exploration inside. Rover handlers decided to abandon attempts to approach the crater's cliff walls when they saw a power spike similar to the one that preceded a broken wheel on its twin, Spirit. Opportunity is already making do with a stuck robotic arm. The mission's manager said, 'Both rovers show signs of aging, but they are both still capable of exciting exploration and scientific discovery.' Opportunity is set to continue trekking across the Meridiani Plains of Mars, even though its wheels have already seen 10 times the use they were designed for. Meanwhile, Spirit has survived yet another harsh Martian winter to produce another striking panorama." Adam Korbitz notes other Mars-related news that funding has been approved for the Search for Extra-Terrestrial Genomes (SETG) Project. The project was one of 15 selected to receive funds through a NASA research opportunity program. The stated goal of the proposal is to "develop a PCR detector for in situ analysis on other planets, most immediately, Mars. This instrument is so sensitive it should allow the detection very low levels of microbial life on Mars, and will determine its phylogenetic position by analysis of the DNA sequence of the genes detected in situ."
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Rover Exiting Crater To Continue Martian Marathon

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  • by Hatta ( 162192 ) on Thursday August 28, 2008 @10:31AM (#24780025) Journal

    PCR requires 2 primers of known sequence, roughly 20 bases long, between 100 and 1000 base pairs apart. Given that we have absolutely no sequence information from which to design these primers, how do they expect to do PCR on completely unknown DNA?

    • by eln ( 21727 ) on Thursday August 28, 2008 @10:34AM (#24780045)

      Using the DNA samples from Area 51 that we obtained from the Martians that crash landed in Roswell, of course. Duh.

    • by Shimmer ( 3036 ) on Thursday August 28, 2008 @10:48AM (#24780255) Journal

      It's much worse than that. What makes them (or you) think that alien life will have any DNA at all?

      They seem to be assuming that alien life will share a common ancestor with Terran life. This seems like a pretty dubious assumption to me.

      • by MyLongNickName ( 822545 ) on Thursday August 28, 2008 @11:03AM (#24780469) Journal

        Because they have to start somewhere? It isn't unreasonable to think that most naturally occurring forms of life are based on DNA. Yes, that is an assumption that could be wrong. We have one data point to work from. If our assumption is wrong, we can create different methods of detection other types of life.

        My question to you: what kind of machine would you put together that would search for microscopic life forms that are of a type we have yet to imagine? When you answer this, then you can mock the article's approach.

        • Re: (Score:3, Interesting)

          I think that's a ludicrous assumption. A reasonably safe assumption is that most life in the Universe is carbon-based, simply because carbon is capable of making the largest and most complex molecules. There's no reason I can think of to think that the end result of any abiogenesis process has to be DNA as the replicating molecule. Carbon can probably be used to produce all sorts of replicating molecules.

          • I noticed that you did not answer the second part of my post. What kind of process WOULD you use to detect these Non-DNA based life forms?

            • by eean ( 177028 )

              I liked the idea that got struck from the Viking mission. Put out a petri dish with some yummy organics, and drop some martian dust on it. See if anything grows.

              IANAChemist, but seems like there should be some way to detect interesting organics other then a DNA test...

              • there is, it's called NMR, now, we'll leave the engineers to put an NMR machine and a robot that can prepare an NMR sample in a lander. Really, the best thing would be to bring the sample back to Earth, that's the only way to test them properly, a single instrument can never tell you what you have, you need multiple tests.

                You could use Mass Spec to get some evidence of big molecules, it wouldn't tell you much about structure, but it would tell you that there's some big carbony molecules there, Beagle 2
          • Re: (Score:3, Insightful)

            by John Miles ( 108215 )

            There's no reason I can think of to think that the end result of any abiogenesis process has to be DNA as the replicating molecule.

            Earth is an incredibly diverse planet, environmentally speaking. The fact that no living things on Earth are non-DNA based makes me think that DNA is indeed the most-efficient way to handle replication. In other words, it's likely to outcompete any alternatives in Earth-like environments that are capable of supporting life to begin with.

            Everything from the extremophiles found

            • Moreover, in the same way that carbon-base biology is far more energy efficient than silocon-based one is the most likely reason all life on earth is carbon-based despite overabundance of silicon on the Earth surface, it has been demonstrated that RNA/DNA is superior on a physico-chemical ground to any other potential data storing chemicals studied.

              There may be somewhere life very different from what we could imagine, but the water/carbon/proteins combination is by far the most efficient one scientists coul

        • by jesdynf ( 42915 ) on Thursday August 28, 2008 @11:16AM (#24780627) Homepage

          My question to you: what kind of machine would you put together that would search for microscopic life forms that are of a type we have yet to imagine?

          A microscope.

          • At first, I thought this was snarky (and it may very well have been meant that way). However, if you could send the probe with a microscope, and a method for having the visual sent back to Earth for a team of analysts, this might not be a horrible idea.

            • by jesdynf ( 42915 )

              Fifty-fifty sort of thing. Didn't some dudes recently make a microscope the size of a dime? I just think we've got better odds dropping microscopes from space and looking to see if they land on marscrobes than we do trying to genetype the damn things. GATTAQA?

            • by drerwk ( 695572 ) on Thursday August 28, 2008 @12:15PM (#24781599) Homepage
              Kind of like the microscope on Phoenix? http://www.nasa.gov/mission_pages/phoenix/news/phoenix-20080814.html [nasa.gov]
              100nm resolution. DNA however is only 3nm wide.
              • by jesdynf ( 42915 )

                Question asked concerned a tool to find microscopic life. Microscopes are an excellent way to go about that. "Gorsh, nothing down there that looks like DNA" doesn't really answer the question, even if "yes, if it existed, it probably DID use a DNA analogue" is a good assumption.

                Of course, finding DNA would be sweet, it's true.

                • Comment removed based on user account deletion
                  • by jesdynf ( 42915 )

                    Yes. I know. That's why I keep talking about microscopic life. Microscopes are good at seeing microscopic life. The poster I was snarking at -- who, if he's reading this, has surely seen justice done at this point -- asked about microscopic life. So I mentioned a microscope.

                    • The problem with microscopes is that you often have to know what you're seeing to understand what you saw.... High magnification images are complex and there are many inorganic reactions that can give you complicated looking structures. Most optical microscopy is done using a pretreated and often stained sample. Likewise electron microscopy. Many microscopic images look like semi random garbage on first look.

                      Now, it's a bit of a no brainer to put some sort of microscopy on future planet probes, but us
              • by smoker2 ( 750216 )
                Informative but irrelevant.
                The microscope is *instead of* looking for DNA. We already established we don't know what to look for with DNA, other than known types. But a microscope can *see*, no prior knowledge needed. We were kinda hoping that alien life would actually be in our dimension, so we should be able to see it.
                I am hoping that when alien life is finally discovered, it will show that we are just another species differentiated by distance like the Galapagos island creatures. Humans are only really j
          • Oh my God. Thank the heavens that you are so much smarter than the scientists at NASA. What would they do without you! I highly recommend they bring you on staff, and you can be in the much vaunted position of "Minister of Keepin' it Real".
        • Re: (Score:2, Informative)

          by waferbuster ( 580266 )

          yep, based on the single datapoint of earth life using DNA, it's reasonable to expect and look for ET DNA. However, after rolling a die once and getting 4 it would be similarly reasonable to expect subsequent rolls to also be 4.
          Extrapolating based on a single datapoint is shaky at best. But without alternative substances to check for, DNA seems reasonable.

          This reminds me of the old saying about when holding a hammer, everything looks like a nail.

          • And that is what is so exciting yet frustrating about this type of thing. We know so very little that we don't even know the right questions to ask.

            (much like sex )

      • Yes and no. I think it is entirely more likely that life inside our solar system shared a common past at some point, than it is for life to just so happened to form completely independent of one another.

        If life happened to form in two different places, independently, within our solar system, either we hit the cosmic jackpot, or life is much easier to form than we ever thought possible. And if that is the case, then through the vast amounts of universe that there is, we would have seen SOMETHING SOMEWHERE f
        • Re: (Score:3, Insightful)

          by Jhon ( 241832 )

          And if that is the case, then through the vast amounts of universe that there is, we would have seen SOMETHING SOMEWHERE from a more intelligent race.

          (A) we're either the first, or basically it takes ~X amount of time (X being the age of the universe) for intellegent life to evolve and we can't see ET sending us signals because he hasn't evolved yet or he's sending them from 200k light years away as we speak and wont see them for a very long time.

          (B) Signal loss is so huge in the vastness of space we just

          • "(A) we're either the first, or basically it takes ~X amount of time (X being the age of the universe) for intellegent life to evolve and we can't see ET sending us signals because he hasn't evolved yet or he's sending them from 200k light years away as we speak and wont see them for a very long time."

            it's very unlikely that intelligent life evolve in two (or more) distinct point of the univerve within 0.0016% of current universe age. The problem might also be far worse: imagine a million civilizations exis

      • Re: (Score:3, Interesting)

        > This seems like a pretty dubious assumption to me.

        We don't know how life arose on Earth but the assembly of complex self-reproducers from simpler compounds doesn't seem like any everyday occurrence. We do know that material can be transferred from Mars to Earth and possibly vice versa. So if we find life on Mars we have three scenarios:

        1. Life arises spontaneously on Mars by unknown mechanism. Life arises spontaneously on Earth by unknown mechanism.
        2. Life arises spontaneously on Mars by unknown mechani
        • >the assembly of complex self-reproducers from simpler compounds doesn't seem like any everyday occurrence.

          The evidence seems to show that the appearance of cellular life occurred quickly after the Earth developed a stable surface cool enough for widespread liquid water. That would argue that "life arising spontaneously" is not particularly unlikely. That might change which variable you assign as A and B in Bayes' Theorem.

          • > The evidence seems to show that the appearance of cellular life occurred quickly after the Earth developed a stable surface cool enough for widespread liquid water.

            That's an interesting but tricky way to argue. After all, what we observe is conditioned on the fact that we are here now and hence that there needs to have been ample time for our own evolution. Frankly, as soon as we veer to close to anthropic arguments I'm no longer as confident as I once was about what arguments are valid. (But check o

            • I think that the anthropic principle is a null statement, and I agree with you that one should tread lightly if you get near it. I don't think it needs to be invoked in this case. I am more concerned about extrapolation from a single datum. The evidence seems to show that prokaryotic life arose quickly on Earth. There was then a really long period before the evolution of eukaryotic life, but that isn't germane here. If the evidence showed that there was a long sterile period before the appearance of pr
              • > There was then a really long period before the evolution of eukaryotic life, but that isn't germane here.

                It might be germane. If the step abiotic->prokaryotic is much more likely than the step prokaryotic->eukaryotic then we'd expect to see precisely the result we see: the first step happening quickly compared to the second step. This would be true even if both steps were a priori incredibly unlikely because we're looking at probabilities conditioned on the fact that eukaryotic life did arise.

        • Or even:

          4. Life arises somewhere else, and is transported to Earth and Mars by a known mechanism

        • by Kjella ( 173770 )

          A simple application of Bayes' theorem tells us that the first is the least likely.

          Hidden in that bunch of pseudo-mathematical drivel you still haven't got a clue what the probabilities are, so you're just making it up. Who says life is rare? We find life in the stranges places here on earth, maybe the solution to abiogensis (creation of life) is blatantly simple but we can't see it because there's so much life, so much competition and evolution it's difficult to imagine the most basic of forms life could take on. If there was any other phenomenon in the universe, any at all, my first tho

      • that got there aboard Viking, Mariner, etc. The terraforming has already begun.
      • the problem is which is which. It should be obvious they are making the assumption that life that we are interested in has DNA. After all, we know about prions (not life, but certainly infective). But unless we have a FULL chemical lab there, we will not know what to look for. So the safest (and easiest) solution is to assume that life has some common grounds. What I am going to be curious about, is that it is possible for DNA/RNA to have different base pairs. This will ahve to assume the bases that we know
        • It's like the stories you hear about an army guy getting the permanent assignment overseas because his "helmet-head spaceman" caught something, is turning black and gooey and the army does not want him bringing it back home.

      • If life is commonplace, there are probably at least some chemical commonalities (carbon, for example). It may be that the formation of DNA or DNA-like molecules is simply inevitable in an organic chemical soup... we really should be checking the composition of organics on asteroids, I think.

        If the test is robust enough to detect DNA-like structures (DNA/RNA/etc with maybe different base pairs, but the same general structure) or complex proteins, i would make a semi-educated guess that we'd be able to identi

      • Re: (Score:2, Interesting)

        by drolli ( 522659 )

        Well.

        a) Working point for life is liquid-solid

        b) To form structures, valence bonds are suitable

        c) Combinatorics requires more than two valence bonds to make different molecules

        d) bonds should be strong in comparison to temperature, yet not forever

        All this make carbon a pretty likely candidate to be involved. Hydrogen is painly so abundant that it *will* be involved and oxygen is also not seldom. So it is not unlikely that life somewhere else may be based on a cemistry similar to ours.

      • That assumption is probably one of the things they are trying to prove, namely did Earth life originate off-planet? If they get a negative result because they don't find common ancestry, they've added some evidence against the panspermia theory.

        • by Shimmer ( 3036 )

          You're kidding, right? If they get a negative result, then they think they don't have life at all and they dump the sample.

      • by mbone ( 558574 )

        What makes them (or you) think that alien life will have any DNA at all?

        The Earth and Mars have been exchanging biological material all along, through meteor impacts. To me, that makes it highly likely that there is a biosystem there, and fairly likely that there is some commonality between the two biosystems.

      • It's much worse than that. What makes them (or you) think that alien life will have any DNA at all?

        Because it may not be alien. Martian rocks have been found on earth. [wikipedia.org] They were apparently ejected into space during metor impacts on Mars, drifted through space, and eventually landed on Earth. It is reasonable to assume that some terrestrial rocks made the opposite journey. Life may have hitchhiked on these rocks in either direction. So Martian life may have originated on Earth, or vice versa.

        • by Shimmer ( 3036 )

          It is reasonable to assume that some terrestrial rocks made the opposite journey.

          No, it is reasonable to hypothesize that some terrestrial rocks made the opposite journey and then design the experiment to test that hypothesis. That's apparently not what's going on here.

      • by Urkki ( 668283 )

        I think the motivation for selecting this particular project was, that improving these techniques will likely have applications here on Earth too.

        But looking for DNA is a pretty good guess for life for any planet that might have life on Earth-like conditions. It might very well be that DNA is the best molecule for genetic information in this kind of environment, and possibly even the only viable molecule in more extreme conditions like current Mars. It has, after all, "enslaved" RNA, and completely wiped ou

    • You can get around the need for primers by fracturing the DNA using restriction enzymes or mechanical sheering to break the unknown DNA into shorter fragments and then ligating adaptors onto the ends of your new 100-1000 bp fragments. Then you use primers complementary to your adaptors and viola you're in business.

      My question is why we'd expect life on Mars to use DNA at all.
    • by Anonymous Coward

      16S RNA gene PCR, the most sensitive detector for life on Earth

      This detector is an amplification strategy called the Polymerase Chain Reaction (PCR) that is based on artificial replication of DNA. PCR is a technique which is used to amplify the number of copies of a specific region of DNA, in order to produce enough DNA to be further analyzed. In order to use PCR, one must know the exact DNA sequences which lie on either side of a given region of interest in DNA. One need not know the DNA sequence in-betwe

      • Re: (Score:3, Insightful)

        by HTH NE1 ( 675604 )

        16S RNA gene PCR, the most sensitive detector for life on Earth

        What part of Mars don't you understand?

    • by Eicos ( 1338783 ) on Thursday August 28, 2008 @11:12AM (#24780565)
      They would use random primers. A DNA hexamer (six-base sequence) is sufficiently long to serve as a PCR primer, but short enough that it would take only 4096 different types of molecule to comprise all possible sequences. Of course, we don't want the sample DNA to be plastered in our primers, so we'll pare those 4096 down to a handful, at least one of which, in any sample sequence of significant length, will nonetheless find somewhere to anneal. Once we've gone through enough cycles, it's likely that we'll have amplified at least some segment of the sample DNA. Then, getting the reaction contents purified and sequenced is simply a matter of applied microfluidics.
    • Re: (Score:3, Informative)

      by SlashBugs ( 1339813 )

      Use random primers, just like you do for reverse transcription when you want to pick up all the RNA sequences in your sample. The reaction's efficiency would take a hit, but if all they want to do is detect DNA (or maybe even sequence a few very short sections) it could probably be made to work.

      A bigger problem is the enzyme used in the PCR. IANABiochemist, but I'd expect the PCR to only work if the Martian bugs hava genomes based on double-stranded DNA chemically very similar to ours.

      There are plenty of st

    • Re: (Score:3, Informative)

      Their working hypothesis (spelled out on the linked page) is that early in the development of microbial life there is (they claim) a statistically relevant chance that microbes developed on either Earth or Mars could have survived transfer from one planet to another via "meteoric exchange", which there would appear to have been a lot more of back ~3.5billion years ago when the first signs of modern-style microbes appear in the geological record.

      Their assumption is that regardless of whether microbial life o

    • Well it's classed as a research project, and I would think - just a guess mind you - that part of the problem may be to get around that issue. Whose to say the technique will look anything like the stuff we're using now.
    • They're looking for a particular gene, which is found in all known life on Earth.

      The gene that has changed the least over the past 3-4 billion years is the 16S (or the related eukaryotic 18S) ribosomal RNA gene. Ribosomal RNAs are the main structural and catalytic components of the ribosome, a molecular machine that translates RNA into proteins (8,9).

      It is the slow rate of change of the 16S gene that makes it the best detector of life. Within the ~1500 nucleotides of the 16S gene, there are multiple 15 to

  • zzz (Score:3, Interesting)

    by apodyopsis ( 1048476 ) on Thursday August 28, 2008 @10:34AM (#24780047)
    so.. we all know what would happen if Microsoft designed a motor car, but what would happen if the Rover Team designed one?

    (I don't know about you, but I think still working after 4 years is damn impressive)
  • Does someone have a link to a medium-res copy? The thumbnail is tantalizing, but I don't want to download a 42MB TIFF.
  • Are there any key lessons to be learned from these rovers' success? Or is it simply that they have no critical consumables (being solar powered and all) and they evidently were overengineered? I guess for starters, having redundancy and the ability to turn off failing components is good, seeing as they're six wheel drive and one of the rovers is now dragging a bad wheel around. What else has been learned from these rovers about engineering long-lasting probes?
    • by Colonel Korn ( 1258968 ) on Thursday August 28, 2008 @10:51AM (#24780303)

      Are there any key lessons to be learned from these rovers' success? Or is it simply that they have no critical consumables (being solar powered and all) and they evidently were overengineered? I guess for starters, having redundancy and the ability to turn off failing components is good, seeing as they're six wheel drive and one of the rovers is now dragging a bad wheel around. What else has been learned from these rovers about engineering long-lasting probes?

      Another lesson to learn is that despite highly publicized mistakes, NASA does have a lot engineers who are both brilliant and wise.

      • by Kjella ( 173770 ) on Thursday August 28, 2008 @11:25AM (#24780765) Homepage

        Another lesson to learn is that despite highly publicized mistakes, NASA does have a lot engineers who are both brilliant and wise.

        I don't think anyone has questioned that. But one mistake from one engineer and it's game over, so it takes a very unique process to deliver on that. Even in healthcare people die because of mistakes, and while fatal to the patient it's not like the hospital will crash and burn because of it. It doesn't matter how remote in the wilderness you are here on Earth, it's a lot easier to fix or try again than any space probe. I think SpaceX is starting to figure out how hard it is to avoid all potential problems at once...

  • Or that Optimus Prime hasn't stomped on it.

  • Re: (Score:2, Offtopic)

    Comment removed based on user account deletion
  • WTF? I think we should first concentrate on finding something that somewhat resembles our microbial life before we spend a lot of government funds to ship a PCR detector there.
    Not only do they assume that life there has genes in about the same way as ours but also that they are made from the same nucleotides. What would be the odds of that? (excluding panspermia and so on).
    • Re: (Score:3, Insightful)

      by DerekLyons ( 302214 )

      I don't see any plans to fly a PCR detector - only to develop a PCR detector. Expanding the technology base for compact, low power, automated laboratory and detector systems will be useful as it could lead to any number of useful spinoffs. Like portable blood sugar analyzers, or pregnancy detection kits, or decreasing the time it takes to perform forensic DNA analysis...

    • Re:Gene expressions? (Score:5, Interesting)

      by clonan ( 64380 ) on Thursday August 28, 2008 @11:18AM (#24780669)

      Actually, there are fairly good odds that alien life uses DNA in a similar way that we do.

      Primarily because proteins/amino acids are the only chemical family that has the variation needed for life to function. Sugars don't have the variety necessary and lipids have difficulty interacting with aqueous environments. the 20 amino acids we use cover the full range of conditions, acid/base/hydrophobic/hydrophilic/big/small/odd (proline). It is unlikley that other lifeforms will use significantly more or less amino acids even if the specific chemistry is slightly different.

      The biggest problem with proteins is that they can't store information. They can't form complements and unfolding a protein to directly read off the amino acid sequence typically destroys the original protein. Life needs a repository of information that is self correcting and is non-destructive to existing proteins.

      Since sugars and amino acids are common (sugar forms easily and amino acids are necessary for efficient life) it is not unlikley that DNA/RNA (which is based off of these two molecular families) would form and it DOES fit the bill for data storage. Since simplicity provides stability, it is unlikley that a huge number of different base pairs would be used so either 2 or 4 bases are likley. Due to space limitations it is very unlikley that a DNA/RNA system would use more than 3 hydrogen bonds and 1 hydrogen bond is too weak. Therefore the list of usefull base pairs drops to either 2 or 3 bonds and we call them adenine, thymine, guanine and cytosine.

      I freely admit that this is based off of an N of 1. But even with that said it is important to remember that life is hard and the simpiler/more efficient a system is the better able a life form is to survive. While the system we use isn't mandatory, it is very likley that it is representative of other similarly effective systems.

      A PCR system would be able to detect the residue of a lifeform that looks even remotly like us on a molecular level. Since we know our system works and we have no knowledge of a different life system it is only reasonable to look for a system we know works. PCR is our best bet for identifying life.

    • In the proposal, they state that they assume viable organisms are occasionally transferred between the planets on meteors. We only find one kind of life here on earth, the DNA-based kind. Since they assume that organisms can be occasionally transferred between Earth and Mars, if there is life on Mars, chances are it's DNA-based. Because either life developed on Mars and transferred here, or life developed here and tranferred there.

  • by OolimPhon ( 1120895 ) on Thursday August 28, 2008 @10:48AM (#24780253)
    "...the Search for Extra-Terrestrial Genomes (SETG) Project..." Sigh. I read that as "the Search for Extra-Terrestrial Gnomes Project". It's late. I'm tired. Perhaps I should stop coding now...
  • I can just see Luke coming up over that ridge in the speeder... too bad for the whole 'no oxygen' thing.

  • Kind of a waste (Score:4, Insightful)

    by Reality Master 101 ( 179095 ) <RealityMaster101 @ g m a i l . c om> on Thursday August 28, 2008 @11:08AM (#24780521) Homepage Journal

    I wish NASA would get off the "looking for ET life" kick. The probability of finding any sort of life on Mars is vanishingly small. I suspect that NASA knows this, but thinks that it can capture the public's imagination (and thus pocketbook) by pushing the whole "Searching For Life" thing. There are so many other experiments we could do that have a much higher payoff.

    I don't think the search for life is going to fire the public's imagination more than the cool photographs they get back. If they *really* want to get the public excited, send an HDTV recorder up there to zoom around... maybe even stereo HDTV so we could see 3D. Let me see a Martian sunset. Those are tactile things that everyone can be excited about. The search for life is an endless string of boring failures. Sure, if it *did* succeed, it would be immensely exciting, but that's like saying it would be exciting to win the lottery, instead of paying the rent. Except winning the lottery is a lot more probable.

    • Re: (Score:3, Interesting)

      I tend to agree as far as finding life on Mars. Even if there is, it's either far under the surface (and it's highly unlikely that any robotic mission is going to get complex enough to wield great big drills), or they're looking the wrong places. I would think a more profitable region to look would be something like Valles Marineris, which at its deepest would have quite a bit denser atmosphere (maybe dense enough for liquid water).

    • Re:Kind of a waste (Score:4, Insightful)

      by fiannaFailMan ( 702447 ) on Thursday August 28, 2008 @12:09PM (#24781479) Journal

      The probability of finding any sort of life on Mars is vanishingly small.

      How can you know this without knowing the outcome ahead of time?

      There are so many other experiments we could do that have a much higher payoff.

      Such as...? And how do you define 'payoff?'

      I don't think the search for life is going to fire the public's imagination more than the cool photographs they get back.

      Sure, if it *did* succeed, it would be immensely exciting

      Which is it? Is the search for life exciting or isn't it?

      I don't think the search for life is going to fire the public's imagination more than the cool photographs they get back.

      Huh? 'Cool photographs' are better than performing actual science to answer one of the greatest questions that has been on the minds of man ever since we discovered that ours was not the only world in the universe? What's it going to be next? Canceling experiments on the ISS to make way for a weekend visit by Paris Hilton?

      OK, I'll give you that the likes of the Apollo program might have had a skewed ratio of scientific usefulness to inspirational value, but I have my doubts that cool photography from Mars is more inspiring than the possibility of finding evidence of life there.

      • How can you know this without knowing the outcome ahead of time?

        Because it's an *extremely* low resource environment. Sure, it's theoretically possible, but it's vanishingly unlikely.

        Such as...? And how do you define 'payoff?'

        Payoff = advancement of knowledge beyond a result of "Negative for life." And are you really that low on imagination that you can't think of any experiments to run on Mars?

        Which is it? Is the search for life exciting or isn't it?

        The *search* is utterly boring. It would be extreme

  • by azav ( 469988 ) on Thursday August 28, 2008 @11:12AM (#24780571) Homepage Journal

    But without all the poverty.

  • Even developing a space-ready PCR system seems premature at this point. What about looking whether there is DNA there in the first place?

  • This instrument is so sensitive it should allow the detection very low levels of microbial life on Mars, and will determine its phylogenetic position by analysis of the DNA sequence of the genes detected in situ.

    So, what makes them think that a DNA based creature from MARS is going to be in any particular phylum that we know and/or can comprehend?

    RS

  • Or is it already dead?

  • Martian Trash? (Score:3, Interesting)

    by trongey ( 21550 ) on Thursday August 28, 2008 @01:30PM (#24782755) Homepage

    Did anybody else who's dowloaded the high res pic notice the white plastic pill bottle just right of center, about 1/3 of the way up from the bottom?

  • More Mars color BS (Score:3, Interesting)

    by Teilo ( 91279 ) on Thursday August 28, 2008 @02:38PM (#24783663) Homepage

    Once again, another BS color image from Mars.

    Anyone who cares to, do this: Open the image in Gimp or Photoshop.

    Look at the per-channel histograms. You will see that someone compressed the Blue and Green channels before posting the image.

    To fix:

    Normalize each channel individually so that 0-255 spans the full channel range.

    The result? Mars as Opportunity actually photographed it.

    Does NASA really think that we are so simple-minded that we would be too confused and disoriented to see a Mars without red sky?

    • Re: (Score:3, Informative)

      by Teilo ( 91279 )

      Here is a before and after, if anyone cares:

      http://tinyurl.com/5mon9r [tinyurl.com]

    • Once again, another BS color image from Mars. Anyone who cares to, do this: Open the image in Gimp or Photoshop. Look at the per-channel histograms. You will see that someone compressed the Blue and Green channels before posting the image.

      You must be one of those people who believe the moon landings were faked.
      Take a look at this image [fotosearch.com] in the Gimp.
      OMG, someone squeezed the blue all the way out!!!

      Hint: Mars really is red, and being almost entirely desert with plenty of wind, there will be red dust in the air.

      • by Teilo ( 91279 )

        Typical knee-jerk reaction. For the record, since you obviously seem to know everything about me: I don't believe in aliens are or have ever been on Mars or anywhere else in this solar system. Cydonia is just a pile of rocks. We really did land on the moon. There. Satisfied?

        Did you look at the histogram? No? Didn't think so.

        • I did look at the histogram. Feel free to enlighten me how you get that the image was tampered with, from looking at that histogram.
          In a predominantly red scene, you will get a red histogram that peaks in the high values, while green and blue will peak at lower values. That's what I'd expect, and that is what I see -- plus sharp peaks that were caused by the bits of the rover that are within the frame.
          Now, take a look at the histogram for that other picture I mentioned, the one with the yellowish-green
          • by Teilo ( 91279 )

            Alright. Answer me this, please. Why is it that every single rover image, has an R, G, and B hump in an entirely different range? Every single image.

            I have looked at thousands of histograms, and I have never seen this pattern anywhere else. I can easily reproduce the effect of course, but never have I ever seen the typical bell-curve of a histogram be consistently different in each channel, image after image, EXCEPT with NASA Mars images, in normal images.

            It is particularly obvious in this image because of

            • Why is it that every single rover image, has an R, G, and B hump in an entirely different range? Every single image.

              Because the rover is on a different planet, with different lighting conditions, different atmosphere, different everything?

              I have looked at thousands of histograms, and I have never seen this pattern anywhere else. I can easily reproduce the effect of course, but never have I ever seen the typical bell-curve of a histogram be consistently different in each channel, image after image, EXCEPT with NASA Mars images, in normal images.

              You have never seen this pattern anywhere else? What exactly are you comparing it to?

              It is particularly obvious in this image because of the blow-out in the channels (the vertical columns on the right of the hump in each histogram). I made another version where I did nothing but adjust the three channels so that that vertical column lines up on all three channels. Not quite as bright, but probably more accurate. Since this camera is, I believe, using a monochrome CCD with filters, that column, present in all three channels, is likely an artifact of the CCD or in the image processing. Since it is the same CCD, with three different filters, those three channels should line up on the column. They should not be in entirely different thirds of the image.

              You say that that "blow-out" or "column" is likely an artifact of... whatever.
              You also say that the camera is, I believe, using a monochrome CCD with filters, etc... That sounds plausible to me, because from what I've read in the past, that's pretty much standard equipment on unmanned NASA missions...

    • by sighted ( 851500 ) on Thursday August 28, 2008 @03:46PM (#24784751) Homepage
      Here's a page that attempts to rebut this: http://www.donaldedavis.com/2008%20new/CLRMARS.html [donaldedavis.com].
      • by Teilo ( 91279 )

        Interesting site, but totally irrelevant to what I note. Check the per-channel histogram. He does not explain how an image can have a histogram such as this, and other similar images have.

        I am not claiming any conspiracy. I am claiming NASA stupidity. Check the histogram. You will see what I am talking about.

    • I will have to wait to look at actual histograms until I get home from work, but it sounds to me like you don't understand image histograms. The blue and green channels can be biased towards the dark end either because someone darkened those channels (which typically results in identifiable artifacts in those channels...spikes or gaps in the histogram), or because there's simply not a lot in the image that is bright in those channels. This is the reason why NASA has the color calibration targets. It's sort
      • by Teilo ( 91279 )

        I believe Mars is red. But I don't believe it is as red as these pictures show.

        And yes, I understand image histograms very very well, as I work with them every day. I understand white balance. This is not a case of biasing. This is a case of clipping, by different amounts, in each channel.

        I will be interested to hear your response after you have actually looked at the per-channel histogram.

    • If white balance were as simple as normalizing the three color histograms, every picture ever taken by every digital camera would have perfect color. Truth is, if the histograms for all three primary colors in a picture span the full 0-255 range, it's a pretty much a surefire sign that the color is incorrect. Cameras have a "neutral" objective view of colors. The only reason we need white balancing is because our brains don't work like that, and insist on fiddling with how we perceive colors depending on
      • by Teilo ( 91279 )

        Yes, I understand this. Deal with it every day.

        Two things: In all the rover color images, the histogram shows a triple R,G,B hump. For a monochrome CCD with filters, that's not normal. I dare anyone to try to duplicate this with natural lighting in any scene, to arrive at such a histogram. I don't think it can be done (but I've been wrong before).

        Second: This image has a giveaway. The histogram, has a wide vertical spike right-center of the bell curve, in all three channels. That spike, likely caused by a C

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