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Space Science

Little Green Plants on Mars? 41

Posted by michael from the body-snatchers dept.
moorhens writes "The BBC is reporting the first evidence for chlorophyll on Mars. Without chlorophyll, plants' green pigment, and photosynthesis, life on Earth would be limited to deep ocean volcanic vents and politicians."
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Little Green Plants on Mars? More

Little Green Plants on Mars?

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  • Scientific press releases (Score:3, Insightful)

    by nucal ( 561664 ) on Friday April 05, 2002 @10:50AM (#3290674)
    Given the controversial nature of their findings and the early stage of the research, the scientists want to hold back any claims about what they may have found until they have done more work and prepared a detailed paper for submission in a scientific journal.

    But they are happy to use a non-peer reviewed press release to publicize their findings. The potential of plant life on Mars is amazing, but the way this news was released is pretty irresponsible.

    • Re:Scientific press releases (Score:5, Insightful)

      by DeadVulcan ( 182139 ) <(dead.vulcan) (at) (pobox.com)> on Friday April 05, 2002 @02:41PM (#3292277)

      But they are happy to use a non-peer reviewed press release to publicize their findings. [...] the way this news was released is pretty irresponsible.

      I have to say, I'm a little tired of hearing the same kind of comments over and over, bemoaning irresponsibility and "bad science."

      I can't find any evidence that these people prepared a press release (if you can show me one, then I might agree with your position). A "press release," remember, is written up and handed to the press. If a journalist comes knocking and you answer some questions, that's not a press release. It seems to me likely that the latter is what happened here.

      And if an eager journalist does come knocking, I would prefer to talk to them myself, rather than leaving them to get their information from people who might not know what they're talking about. Nor do I think it's a really good idea to be doing scientific work in secrecy (yes, even secrecy from journalists). I, personally, would want to be able to impress on them what's certain and what's not. If they ignore me, then they are the ones being irresponsible, not me.

      Now, the whole cold fusion story was poorly handled precisely because the scientists didn't merely talk to the press, they themselves took it to the press before they took it to a peer-reviewed journal. There's a very, very big difference, IMHO.

      This BBC article wasn't even that poorly written, either. There was a bit of poor word choice ("two areas close to Pathfinder [...] have the spectral signature of chlorophyll." - I think "a spectral signature consistent with that of chlorophyll" would have been more accurate); but it wasn't all that bad, I think.

      • This is an abstract of a poster that Dr. Stoker is presenting Search for Spectral Signatures of Life at the Pathfinder Landing Site [astrobiology.com] at the Astrobiology Conference next week - presumably sent in a while ago.

        The Superpan, an image product from the Pathfinder lander camera, is a multispectral panorama of the Pathfinder landing site acquired in 15 wavelengths in the spectral range 440 - 1100 nm. We have performed an automated search of the Superpan image cubes for the spectral signature associated with chlorophyll. First, images were calibrated to radiance values and then the multispectral images were co-registered to subpixel accuracy. An automated pixel-to-pixel search was performed on a 3-filter set of images (530 nm, 670 nm, 980 nm) to identify pixels where the following condition was met: 530 nm > 670 nm, and 980nm > 670 nm. Thus, we searched for the spectral signature associated with red light absorption by chlorophyll. When this case was met by the search routine, we plotted a full spectrum for the involved pixels and carefully examined the images. The condition was met for small areas in six image cases. All of these cases occur in near field images, where resolution is highest. Four of the cases occur on the spacecraft and appear to be associated with spacecraft structure. Two intriguing cases occur in small areas on the ground near the spacecraft.

        So it was an abstract, not a press release. And partially cmpleted studis are certainly fair game for a scientific meeting. But, if it is not ready for publicaton in a scientific journal, than why is it ready for the popular press? Obviously Dr. Stoker's call ... granted, getting BBC-caliber press is tough to turn down.

      • From a Space.com article [space.com]:
        "Stoker has said they did not find evidence of chlorophyll or any evidence of life on Mars," the spokesperson said. "There's really nothing to report. I think they [the BBC] read more into the abstract than is really there."

  • We need to go to Mars (Score:2, Interesting)

    by jspey ( 183976 )
    Dammit, can we just send some people to Mars already? All this work with robots going around and looking at Mars and analyzing the soil and air and whatever is impressive but we'd learn a lot more if we could just send some people out there and have them do the collection and analyze everything and bring some of it back with them. People can travel a lot farther than the little robot rovers can and they can do it a lot more dependably and there's a lot more that can be done to analyze Martian soil and air here on earth rather than on site. Argh! Stupid polititians not giving stupid NASA enough money to build a stupid spaceship to go to stupid Mars. Well, hopefully this discovery will spur someone to go to Mars. Well, unless they end up not finding conclusive data.

    Mr. Spey
    • Personally, I would like to see a truly international effort to do this. After all, it just costs USD 4 billion for the first mission and 2 for each consecutive one (the "Mars Direct" program). That shouldn't really be such a big problem on an international budget...
      Anyway, I think the Chinese space program must have aspirations of this kind already. It would be such a huge PR win for them.

      • After all, it just costs USD 4 billion for the first mission

        You're off by quite a bit. The Mars Direct plan would cost about $50 billion USD to get off the ground. However, according to Zubrin, that cost is also spread out over about a ten year span. Note that the $50 billion gets us a year-and-a-half long stay on the surface of Mars. This is also doable with current or almost-current technology.

        However, the "Battleship Galactica" approach that NASA in the early 90s wanted to take, which was to build some massive support ship, with separate landers, building everything in orbit, would've been $500 billion - and netted us only a 30-day stay on the planet surface. And it would've required invention of an awful lot of stuff.

        • However, the "Battleship Galactica" approach that NASA in the early 90s wanted to take, which was to build some massive support ship, with separate landers, building everything in orbit, would've been $500 billion - and netted us only a 30-day stay on the planet surface. And it would've required invention of an awful lot of stuff.

          Yeah, but it would have built Battlestar Galactica, with cool robots and ship-launched space fighters and stuff. Oh well, back to playing "Wing Commander".

        • You are right, I conveniently ignored the initial investment in hardware (slight memory leak on my part!). However, the $50 billion you quote is not for the Mars Direct, but rather an Enhanced Mars Direct, a case of "double the size, double the cost". The initial investment should be between $20-$30 billion, with 2 billion per each mission (I am quoting Zubrin's book now, no more memory games!). This amounts to just 7% of the US military and civilian space budget.

          • The initial investment should be between $20-$30 billion, with 2 billion per each mission (I am quoting Zubrin's book now, no more memory games!).

            Ah. It's been a while since I've read it, and my memory has never been what it used to be.

            :)

      • It would be quite funny if the Chinese hacked together a solution on this one, or maybe did a combined effort with the Russians.


        Seems like the USA is the place everybody is holding back on the possibilities of space, it is the Russians who are up for opening up to tourism, the Chinese who have the big dream for their country, Europeans doing a solid commercial job of launching satellites down Guyana way.


        Oh, Don't forget it is Yuri's night this Friday...

  • You forgot lawyers... (Score:4, Funny)

    by swillden ( 191260 ) <shawn-ds@willden.org> on Friday April 05, 2002 @11:05AM (#3290790) Journal

    ... but maybe you were just oversimplifying, since lawyers are larval politicians.

  • Close examination revealed that four of the cases occurred on the Pathfinder spacecraft itself. But two regions showed a chlorophyll signature in the soil around Pathfinder.

    The fact that four out of six possible matches are on the spacecraft makes me really skeptical about the whole thing. Moreover, from reading the article, one might think they took just "any old picture" from the mission and ran it through some simple filter algorithms, to see if they found something interesting. Of course, such methods can be very valuable tools, especially at large scales, but this looks like a bit of overinterpretation to me. Plus chlorophylls?!? Come on, shouldn't we be able to detect those from orbital images or even Hubble, especially if they are so abundant in the soil?

    • Looking for a particular spectral signature probably just means looking for pixels with RGB in a certain domain. Maybe they have some other channels too: IR and UV from detectors alongside the camera (that might explain the 'image registration' issues), so they're looking at multispectral images. Either way: extraordinary claims require extraordinary evidence and pixels of a particular colour are barely even interesting - let alone extraordinary. Sounds like yet another scam to get funding to me.
      • I take back what I said about a scam. I had a look at the abstract of the poster on the web site. This is just a poster. This is no giant research project, it's just someone who's had the initiative to do a nice little analysis of old data and put up a poster about it at a conference. They're not making wild claims and all that's available online is an abstract. This is about as far from publication as you can get. This is truly terrible reporting by the news agencies.
    • Since four of the six spectra were located on the pathfinder itself, the area around the site could have been contaminated by the little rover running around. It wouldn't take that much contamination to get a false reading.

    • (* Moreover, from reading the article, one might think they took just "any old picture" from the mission and ran it through some simple filter algorithms, to see if they found something interesting. Of course, such methods can be very valuable tools, especially at large scales, but this looks like a bit of overinterpretation to me. *)

      It is not that much different than people who stare at images looking for faces, Snoopy, words, and other patterns. There are a couple of funky webpages devoted to "patterns" found by people with too much time on their hands using lander and orbiter photos.

      I bet an Elvis image filter would turn up just as many matches.

      People have been seeing "patterns" on Mars at least since the "Canali" days, where astronomers swore they saw strait, linear "canals" on Mars.

      Too many false alarms WRT Mars.

  • Piss-poor science.... (Score:3, Flamebait)

    by Doctor Fishboy ( 120462 ) on Friday April 05, 2002 @12:09PM (#3291285)
    I'd be extremely interested to see their 'spectra' of the chlorophyll patches. I've worked with broadband astronomical imaging for a few years, and even straight forward accurate photometry can be fraught with subtle systematic effects due to the nature of the camera and the filters. My money is on scattered light from a combination of the sun-camera-rock position causing the measured colours to go skew, or an inorganic mineral with a similiar response curve to chlorophyll.

    Of course, I can't go and look at the paper for myself because there is no refereed and accepted paper - releasing it as a press release when the work hasn't been peer-reviewed is just fucking stupid.

    Sloppy. Damn sloppy.

    Dr Fish
  • All of the detections occurred close to the camera. ... Close examination revealed that four of the cases occurred on the Pathfinder spacecraft itself.

    I bet we just brought cloryphyll to Mars. I wonder if anything will come of it?
    • I bet we just brought cloryphyll to Mars. I wonder if anything will come of it?
      Wouldn't that be a hoot if the Pathfinder mission inadvertantly brought some terran photosynthesizing organism to Mars? Universities and think tanks having sunk untold amounts into the research and study of terraformation just to have it take place where NONE of them would get the credit?

  • The article says the claims come from Dr. Carol Stoker of Nasa's Ames Research Center. This is Nasa, so I wouldn't be so quick to shoot down these extraordinary claims. Nasa sent real men to the moon. It's not like they're claiming to have developed an anti-gravity device.
    • Whether they work for NASA or not is irrelevent, really. NASA employs plenty of scientists, none of whom have much to do with sending people to the Moon or anything else in that vein. NASA's scientists are, on the whole, no better or worse than the ones you'll find at every university and college in the country. And even if they did have a brighter population on the average, that doesn't mean that they can't be wrong. Espeically since they so often disagree with each other at NASA. (Remember ALH84001, the Martian meteorite that may have had life on it? Most of the people most strongly for and against those claims are at Ames.)

      Put simply, arguing from authority is poor science. Particularly when the authority is an acronymn.
      • (* Whether they work for NASA or not is irrelevent, really. NASA employs plenty of scientists, none of whom have much to do with sending people to the Moon or anything else in that vein. NASA's scientists are, on the whole, no better or worse than ..... *)

        The statement you are replying to was meant to be humorous (and was IMO). You see, Nasa *did* actually spend money on some allegedly dubious anti-gravity research. Slashdot ran a story about it a month or so ago. Many classified the experements as no better than perpetual motion gimmicks.
  • mmmmm..... cant wait to taste some Mars plants..... or even better some Mars animals........ mmmmmmmmm..... [kidmoe.com]
  • here's a little theory i just thought up (that i'm sure is wrong, i just don't know why - yet):

    in this article, they stated that they're looking at "two regions showed a chlorophyll signature in the soil around Pathfinder."

    it seems to me that life (using earth as the only analogue) will evolve to fill it's surroundings. in the case of the earth, these are far reaching - from deep sea volcanic vents to below the earth's surface, etc. point being, life adapts in an attempt colonize new areas.

    if there was life on mars now (which i *hope* is true, but i doubt for many reasons - this one included), would it not have expanded to be more than a couple of little patches accross a vast plain like this??

    there are a few possibilities to reject this hypothesis, but none that i find convincing:

    1) the *life* in question has just arrived/come into being, etc. or another way to put it is that it hasn't had time to radiate into the other areas yet.
    i'm gonna use the 'what are the odds we showed up right when life started' argument against this here.

    2) these two areas are 'special' in some way that they can harbour life, but not anywhere else on the plain.
    as well as the 'what are the odds of us landing here' argument, i'd also like to point out the tenacity that life shows on earth to move into new ground - in this case (apparently) *very* similar to the two areas in question.

    3) i'm sure there are other (and better) counter arguments, but i can't think of them so i'm asking you...

    this post is not against this finding per se, it's more of a hypothetical question of:
    "would we ever find tiny pockets of life on a planet (assuming sufficient time for life to evolve/expand)??"
    • "would we ever find tiny pockets of life on a planet (assuming sufficient time for life to evolve/expand)??"

      Life expands until it encounters a limiting factor. In this way, you can compare the expansion of life to a chemical reaction (appropriate, since the functions of life ARE chemical reactions).

      100H2 + 100O2 ---> 100H2O +50O2

      In such a case you wouldn't complain about all that "extra" oxygen. Now we apply the same thing to resources required for life -- such as water. If there's only 1 square meter of water on Mars, would you be surprised to see only tiny pockets of life? No.

      If there is life on Mars, it may only exist in tiny pockets -- we may not even be able to deduce what the limiting factors are.
  • The editor clearly did a poor job. The corrected version is below. In order to avoid introducing any editorial bias that might twist the author's intent, paragraphs where either included or deleted in their entirety. The only changes I made [in brackets] are three corrections of fact fully supported by later statements.

    An analysis of data obtained by the Pathfinder mission to the Red Planet in 1997 suggests there could be chlorophyll - the molecule used by plants and other organisms on Earth to extract energy from sunlight - in the [Pathfinder spacecraft].

    Researchers stress their work is in a very preliminary state and they are far from making definite claims.

    A detailed analysis of the images of the landing site now reveals     [four areas of the] Pathfinder that have the spectral signature of chlorophyll.

    According to experts it might be highly significant - or could be just a patch of coloured     [paint].

    In Dr Stoker's study six regions of the Superpan matched positive for the chlorophyll signature.

    Close examination revealed that four of the cases occurred on the Pathfinder spacecraft itself. But two regions showed a chlorophyll signature in the soil around Pathfinder.

    -
  • Chlorophyll wasn't invulnerable to huge lethal curie counts. With the surface radiation as high as it is I find it highly unlikely that ANY life exists on Mars. It would get cooked.
    • Since we don't have a real sample of the plant life form, if there it is indeed there, we can't say how it differs to what we find on Earth. Since there are bacteria that can withstand amazing amounts of radiation, and others that can withstand other extreme conditions, what is there to say that no plants have cells adapted to this sort of environment. Heck, what even says that the source of the chlorophyll signature are plants, it could just as well be from bacteria that uses cholophyll for its soucrce of energy.

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