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Space Science

The Viking Landers, 25 Years Later 99

Posted by timothy from the where-babies-come-from dept.
bavid314 writes: "CNN has a decent story looking back on Viking I and Viking II. For someone who wasn't alive at the time of the landings, it provides a good synopsis. Furthermore, it evokes the question of why recent missions fail to include biological experiments to test for the presence of life."
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The Viking Landers, 25 Years Later More

The Viking Landers, 25 Years Later

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  • Re:is miniaturization good or bad? (Score:1)

    by Anonymous Coward
    And just how open are the Russians when it comes time to announce failures? You only assume that they have a decent success rate...

  • Re:Intelligent life (Score:1)

    by Anonymous Coward
    Not when you dial down the middle - 1-800-CALL-ATT.

    Oh no....those stupid ads have taken over.

  • Bill Weller took four Mars Pathfinder images and created an animated, 3-D stereogram of something popping out from behind a rock. (Hope you are good at crossing your eyes to resolve those "Magic-eye"-type images.)

    He nicknamed the organism the "Zolax [google.com]." (Scroll two-thirds of the way down the page to see it.) If it resembles any earth organism, I would say the tarantula -- although it seems to have a half-dozen or so "tentacles," rather than articulated legs. If you look closely at the lower-left corner of the image, you'll even see one of the tentacles in contact with the ground. The point where it's attached to the body is hidden behind the rock, and it's casting a shadow! If this is a hoax, the hoaxer showed admirable attention to detail.

    Disclaimer: the other purported anomalies on this web page are pretty dubious. (Don't you hate when some wacko points to a JPEG artifact and says "look, an artificial structure!" or "look, an organism!") I wish they weren't on the same page as the Zolax, because they hurt its credibility. Nevertheless, the Zolax looks like the real deal. It appears in both the left and right cameras simultaneously, so it can't be an image-processing artifact. It could be a hoax, but it would take a lot of effort to fake a stereo image like this.

    It would be nice if we knew the time interval between the two frames -- then we'd have an idea of how fast this critter moves.

  • If you want to debunk this, then instead of being flippant, why don't you come up with an alternative explanation for this object seen by both the left and right cameras?

  • A bit of family history (Score:3)

    by deeny ( 10239 ) on Monday July 23, 2001 @09:32AM (#67927) Homepage
    I've always been proud of the fact that my dad worked on one of the "search for life on Mars" projects -- the GCMS project (gas chromatograph mass spectrometer, affectionately dubbed the "green-colored Martian sniffer").

    Those were the days when we did big space science, before we lost some of our hope.

    But boy did it make the "what my parents do" presentations more interesting for me.

    Dad's retired now, but he taught me how to program (a career I likely wouldn't have if it weren't for the space program) and gave me the foundation for a good geek life.
  • ...about using handedness of molecules to test for
    biological processes - is there an error in there
    somewhere? If similar biological life evolved
    independently on Mars, it would prefer one or the
    other handedness. A better test would be to
    have a sample that initially contains both types,
    in equal measure, to expose it to your sample,
    and then to see if the ration had changed.

    And isn't this actually an idea of Richard
    Feynman's, from one of his public lectures? I'm
    pretty sure I've heard it before...

    K.
    -

  • Re:Life on Mars is not necessarily carbon-based (Score:3)

    by FreeUser ( 11483 ) on Monday July 23, 2001 @06:38AM (#67929)
    If a silicon-based one was possible, Earth was the perfect planet for it.

    Well, perhaps not. If carbon life is 100,000 times more likely to develop than silocon life (for reasons mentioned elsewhere sucn as silicon's weaker binding properties and lower reactiveness in simple compounds), and earth has 10,000 times more silicon than carbon, then under those conditions carbon based life is still 10 times more likely to develop than silocon based life. This by no means rules out silocon based life at all. Indeed, perhaps the presence of carbon, even in smaller amounts than silicon, was sufficient for carbon based life to evolve first, preventing any silicon life from ever developing (or outcompeting it in the primordial soup, which amounts to much the same thing).

    In which case earth would not be the perfect place for silicon based life to develop, as it has been "poisoned" by the presence of carbon. This does not remotely prove, or even strongly imply, that silicon life can't and won't develop elsewhere. It merely suggests that, in earthlike conditions, carbon life is much, much more likely to develop. Even that is uncertain, as we have but one data sample, namely the Earth. The opposite could well be true: maybe silicon life is ten times more likely to develop than carbon based life, but we are one of the "ten percent" which have, nevertheless, developed carbon based life. Without additional datapoints (other worlds) the best we can do is make suppositions about this sort of thing, and any supposition we do make is necessarilly suspect.
  • How do you design a test for life that is all-encompassing? Isn't it arrogant to assume that our definition of life (that which revolves around our ball of dirt) is the only definition? What about a silicon life-form? We are designing tests for carbon-based life, tests for earth life.

    What kind of test could we send to detect microbial life that diesn't meet our definitive tests?

    This, I believe, is the one major and convincing point to send a crew to mars. not to do the photo-op fluff piece, but a 1 week or 1 month stay trying to grow everything in petri dishes,etc...

    I doubt any super simple probe test will ever product any conclusive evidence that will be accepted. On the other hand, short of bringing back a 3 eyed green martian, wont convince many in the poloticical-scientific community.
  • Maybe we should tell them the truth, that all the chimps we sent into space came back super-intelligent.
    --
    NASA doctor

    --
  • Levin thinks he knows how to find the answer. All known life on Earth prefers so-called right-handed sugars and left-handed amino acids. So researchers should repeat variations of his 1976 labeled release experiment, using those sugars and amino acids in one test. And in another, they should use their mirror images -- left-handed sugars and right-handed amino acids.


    Yes, all know life is based on left-handed amino acids, but nothing precludes right handed amino acids. The currently theory on right versus left it just chance dominance of a community (well, as much of a "community" as you can have out of stray amino acids in primodial soup) that grew from one side of a crystal instead of another. And later, since the two can't exchange amino acids, symbiotic co-habitation was basicly out of the question, and it was inevitable one group would dominate over the other.
  • Of course: "choose" not "chose".

    "I previewed! Honest!"
  • That was the problem. All the average person saw was rocks, sand dunes and pebbles. Just like somewhere on Earth that you know you saw in National Geographic sometime.

    Too few could make the mental connection to realize: "HOLY SHIT! THIS IS ANOTHER PLANET!"

  • Question: When the first pictures from Viking 1 where released, what did Time chose to put on the front cover that week?

    Granted they put a little teaser pic in the top-right corner with the caption Inside: Mars.

    And you think there is less interest in space now?
  • There's a lot of reasons carbon-based life is favored among the different choices available, not least of which is carbon's very average electronegativity. Some believe that is required for a backbone atom, allowing it to bind most anything from either end of the periodic table.

    mefus
    --
    um, er... eh -- *click*
  • But I don't think that smaller and cheaper is worse... it obviously reduces the impact in case of a failure.

    Even a small probe needs a huge rocket to launch it. Indeed a small probe may need a more expensive tracking network, since the eaiest way to cut down of weight is to make smaller solar arrays or RTGs.

    Moreover, I would reason that the instruments used in modern probes are lighter, cheaper, sturdier, smaller, more powerful versions of the ones used on the big old probes.

    But the old stuff is likely to be a lot more resistant to radiation. The smaller a circuit the eaiser it is for a single charged particle to mess things up.

  • Re:Life on Mars is not necessarily carbon-based (Score:3)

    by mpe ( 36238 ) on Monday July 23, 2001 @02:43AM (#67938)
    Well, similarly, I see no reason why Mars wouldn't be teeming with life that's not carbon-based.

    Problem is that no-one can come up with any kind of chemistry which can be as complex and varied as carbon based organic molecules. Also these kind of compounds are very common.

    A more definite answer to that question (and a nice exercise in interstellar navigation and precision landing) could be obtained by landing a probe right next to one of the Viking probes and

    a horribly compex piece of navigation. Also the only time anything like this has been done used a manned lander

    seeing if some of the materials they were made of have been chewed at, or consumed, at a rate that's not explainable by natural phenomena.

    Only proves anything if this has actually happened. Martion lifeforms might find a terestrial machine inedible, or take a long time to noticably consume such a large object.

  • Re:Life on Mars is not necessarily carbon-based (Score:3)

    by mpe ( 36238 ) on Monday July 23, 2001 @02:50AM (#67939)
    That doesn't exclude other forms of silicon-based life, but chances are any life that is out there is carbon-based (though not necessarily the same as carbon-based life as we know it.)

    Possibly similar compounds, but different in issues such as chirality. (Some common organic compounds have multiple chirality). Also it's perfectly possible to have amino acids, fatty acids, sugars, nucleic acid base pairs which do not exist in terestrial organisms. Let alone that you can have different "genetic codes" even with DNA/RNA chemically similar to that on Earth.
  • 25 Years ago they actully managed to get through with this kind of missions. Nowadays they just plain fail

    25 Years ago they still had popular support, the moon race had totally inflamed the public, the Big Bad Russian(tm) had been beaten to it, and now those sneaky Russian were at it again, this time for Mars.

    That's why NASA had a budget of over 1Billion for the Viking lander.

    ...Time changes...

    The Russians are now Firendly but Poor(c), most people remember the moon landing as something only their dad talks about. And people want results right here, right now, because for them NASA is just another TV show in their 400 channel choice.

    That's why NASA made 130Million probes, and try to get as much science as they can out of them. Meaning that they'll use off the shelf equipment as much as they can, and try to cram every new technollogy into the smallest mission (the DS1 is an exellent example). They even (succesfully)landed a prob on the asteroid Eros, even though that prob had never been designed to get closer than a couple hundred kilometers to it.

    Murphy(c).

    Murphy.
  • One probe failed because the engineers thought in newton meters and the designers thought in feet per second per second. (Or the other way around.) This caused the probe to go off course.

    One failed because it crashed, it was landing in an area that hadn't been surveyed. Significantly, Viking DID survey the area before they landed, which is why they missed the July 4 target landing date.

    One (climate observer?) failed due to a lack, apparently, of redundancy in the control systems.

  • Viking 1 was originally scheduled to land on July 4, 1976. When the scientists saw the survey images, a week or so earlier, they saw a rock garden and said "No way we can land there!" and it took them a couple of weeks to find a good landing site. The Viking orbiters (yes, orbiters, each Viking had an orbiter and a lander)were, IIRC, the first to take sub-kilometer images of the Martian surface.
  • until hot chimneys were discovered at the bottom of the Atlantic, most scientist took for granted that life needed oxygen

    uh, wrong analogy. anaerobic lifeforms (e.g. lactic acid bacteria) were already well known to early biochemists (19th century stuff). The extremophile analogy is closer. Speaking of which: the fact that life will occur almost everywhere, I think, is further reason to doubt that the Mars Meteorite (I forgot the number) contained evidence of Martian microbes: if they were there, they should still be there and thriving and easily found, even in the Martian extremes.

  • My grandfather was procurement officer for the Viking I program at Langley, they had a a reuninon party which I attended. Everyone kept remarking about how everyone worked together then and how now it's a giant rat race, everyone competing against each other. It's a good point to observe, the companies are very cutthroat now adays, and don't cooperate as much as they used to. Look at the unit conversion (or lack thereof) that caused the probe to crash. Lack of cooperation. Patrik
    -------------
    Just your ordinary BOFH :) http://pjbutler.dhs.org/me
  • Thank you Tommy Lee Jones.....
  • I think it would be cool if every geek who has ever looked up at the night sky and wondered sent their silly $300 IRS refund to NASA. If GWB can't figure out a good way to spend it, maybe we can.
  • yup, but you're missing the point. If any sort of stereoscopic preference is found, then that's a pretty damn good evidence that it's life. Only stereoisomers can distinguish other stereoisomers from mixes of both the left and right handed molecules, and there is no known non-biological source for stereoisomers, for so if the Martian soil can distinguish between left and right handed amino acids, you know that something is up. Of course, it might be even more exciting and have more implications if the Martian life is left-handed like we are.......
  • "In 1997, Biospherics' President and CEO, Dr. Gilbert V. Levin, announced his new conclusion that his 1976 Viking Labeled Release (LR) life detection experiment found living microorganisms in the soil of Mars. Objective application of the scientific process to 21 years of continued research and to new developments on Mars and Earth forced this conclusion. Of all the many hypotheses offered over the years to explain the LR Mars results, the only possibility fitting all the relevant data is that microbial life exists in the top layer of the Martian surface." Details here [biospherics.com].
  • You can't have long, stable chains of silicon only, but you can if the chain is made of alternating atoms of silicon and oxygen. The Si-O bond is stronger than the Si-Si bond. This is is the basis for the manufacture of silicones.
  • I know of no one who claims that these researchers are exaggerating their claims.
    Search google using keywords "alh84001" and "exaggerated".
    --

  • Re:conspiracy to keep the dollars flowing? (Score:3)

    by SIGFPE ( 97527 ) on Monday July 23, 2001 @06:26AM (#67951) Homepage
    Propaganda is more subtle than just saying facts outright. NASA carefully use language like 'suggests that...' which seems incredibly modest but the sum total of these claims are in fact much stronger than the evidence allows. It's like me saying "I'm not 100% sure, but some evidence does suggest that maybe I do have some limited telekinetic ability". Modest language but an outrageous claim.

    The fact that it didn't succeed in raising funds is in no way evidence that it was in fact a ploy to raise funds. In fact I have been complaining about NASA's exaggerations for many years now on the grounds that it's short sighted, people will eventually see through them, and thus the money will suddenly dry up due to disillusionment with the whole subject of Mars.

    --
  • Take a look at this [spacedaily.com] article about the Mars Climate Orbiter.
    To lose one Martin orbiter may be regarded as a misfortune. To lose a second looks like carelessness. NASA's previous Mars mishap, the loss of the $1 billion Mars Observer in 1993, was instrumental in causing the switch to more frequent, cheaper missions. But some scientists wonder if the pendulum has swung too far.

    "We've been saying all along they were going to lose one of these things," says one. "With 'faster, better, cheaper' you work your people to death," agrees Peter Smith of the University of Arizona, principal investigator for Mars Polar Lander.
    Problem is, if you want to make a smaller, cheaper, lighter version of a probe, 'sturdier' definitely doesn't come into it. Furthermore, when you make budget cuts on projects like this, the first thing you lose out on isn't hardware but manpower. Granted that the Russians seem to be able to take off-the-shelf parts, weld 'em together, wind up the rubber band propellant system, and end up with a working probe, but NASA isn't about to evolve the ability to work this way just because you take away their funding. It'd be more useful to get the Russians in to manage it ;-)

  • Re:conspiracy to keep the dollars flowing? (Score:3)

    by kaiidth ( 104315 ) on Monday July 23, 2001 @01:46AM (#67953)
    Here's [nasa.gov] a NASA archive on the subject of the Martian meteorite... and the initial press release [nasa.gov]. It doesn't read as particularly sensational, being full of language like 'suggests that', 'is believed that' and a quote from a Dr Richard Zare, a Stanford chemistry professor, "It is very difficult to prove life existed 3.6 billion years ago on Earth, let alone on Mars."

    Of course, it's still a massively controversial subject and they must have been hoping that it would be good for their funding. The press release was dated August 1996, which is certainly a good time for NASA to have been feeling a bit poor [ndia.org]. In fact, looking at the 2000 NASA budget testimony [permanent.com], if the 1996 release was a bid for funding, it really didn't work very well.

  • 25 Years ago they actully managed to get through with this kind of missions. Nowadays they just plain fail.

    What gives?

  • Yup, silicon atoms just don't like attaching themselves to other silicon atoms like carbons does. IIRC, over about 6 atoms in a chain is totally unstable. My high-school chemistry teacher spent about a 1/4 hour going into (too much) detail as to why silicon-based life just wouldn't happen (prompted by that X-Files episode with some sort of plant/fungus thing that was silicon-based [I don't really remember the plot, but I'm sure plenty of folk here do]). Carbon's just really good at forming the sorts of molecules needed to make an organism.

    Of course, we could always find a planet populated by robots a la Transformers....

  • Bill Waterson, Calvin and Hobbes. "Sometimes, I think the best evidence that there's intelligent life in the universe is that none of it has tried to contact us yet."

    The only "intuitive" interface is the nipple. After that, it's all learned.
  • The experiments on the viking landers to determine if there was or was not life present were originally designed not to give a binary answer: you could get back "yes" or "no" or "maybe" as a result. However, congress balked at the idea of spending all that money and not getting back a definite answer. So, to get the appropriation, the project simply redesigned the system so that if the answer was "maybe", it would return "no", and they got the money.

    So the landers went to Mars, tested the soil, and sent back "no, there is no life on Mars."

    Not long thereafter, somebody took a soil sample, took it back to the lab, dumped it in an identical test rig, and discovered that there's no life on Earth either.

    After reviewing the raw data from the lander some 20 years later, it was determined that really the answer should have been "yeah, probably" all along. However, this didn't get any press because NASA was busy trumpeting their new Mars program.

    (This is what I get for talking to my friendly neighborhood astrophysicist.)

  • Re:Life on Mars is not necessarily carbon-based (Score:5)

    by ozbird ( 127571 ) on Monday July 23, 2001 @01:51AM (#67958)
    Try getting an organic chemist to say "silicon-based life" with a straight face.

    IANAOC, but the short answer is that while you can substitute silicon for carbon on paper, the properties of silicon are different enough to make this impossible in practice. For instance, the silicon equivalent of methane (CH4) is silane (SiH4) which spontaneously burns on contact with oxygen. Silicon-to-silicon bonds are weaker, so making large compounds is difficult; smaller silicon compounds (e.g. SiO2) are often stable and unreactive.

    That doesn't exclude other forms of silicon-based life, but chances are any life that is out there is carbon-based (though not necessarily the same as carbon-based life as we know it.)
  • You have to keep in mind that planets aren't closed systems. For one thing, they don't possess a fixed amount of energy, because some is radiated out into space, and some is absorbed by the planet. Planets don't even have fixed mass as asteroids frequently enter the atmosphere and become a part of the planet. Thus, as long as there is a positive or negative flux of energy, it is probably possible for planets to exist in states not in chemical equilibrium without the presence of life. Of course, depending on how loose your definition of life is, then lifeless planets not in chemical equilibrium might be considered alive. -Markus

    "That explains the milk in the coconuts."
  • Of course NASA tries to keep the public interested in space exploration. Without the support of the public, there would not be any space exploration.

    Space tourists, life on Mars, etc., are the sort of thing that Joe Public wants to see. These are also the sort of stories that get covered in the media as well.

    This is a necessary evil in this modern world of economic rationalism we have built.

  • As any of the alien life forms that have visited our planet will tell you, the only true way to test for life is with an Anal Probe. [akamai.net]

  • Re:Life on Mars is not necessarily carbon-based (Score:5)

    by TomV ( 138637 ) on Monday July 23, 2001 @03:27AM (#67962)
    A more definite answer to that question (and a nice exercise in interstellar navigation and precision landing) could be obtained by landing a probe right next to one of the Viking probes and seeing if some of the materials they were made of have been chewed at, or consumed, at a rate that's not explainable by natural phenomena

    This is roughly the insight that led to the Gaia hypothesis.

    James Lovelock came up with the idea when he was hired to do some life-detectors for Viking. His reasoning went along the lines of:

    • 'Life' can be taken to refer to a property of a system that allows it to stay in a non-equilibrium chemical state. (bear with me)
    • 'life' achieves this by interaction with its environment.
    • This interaction therefore leaves the environment in a non-equilibrium chemical state - for instance the Earth's atmosphere wouldn't contain 20% oxygen in the presence of lots of reducing agents unless something is actively producing fresh oxygen.
    • therefore a nice test for life on, e.g., Mars is to look at the chemical composition of the atmosphere and see if it's chemically stable in isolation. Which, disappointingly perhaps, it is.
    The nice bit about this approach, I thought, is that it uses a sufficiently generic definition of life that it avoids the carbon-centric issue. As long as you go along with his 'life' definition.

    The really hairy conceptual leap from there is the full-on Gaia hypothesis which roughly says that if 'life' is defined as above, then the whole Earth might be treatable as 'life' since it's out of chemical equilibrium. Take it or leave it - Lovelock refuses to refer to Gaia as other than a Hypothesis.

    Good piece or Gordian-knot cutting by Lovelock, I thought.

    TomV

  • Oh yeah. And I was reading Astronautica a few days ago about the Luna series and other probe series... for Luna I think they blew up something like 6 missions, launching one every month, before putting a spacecraft in an orbit around moon, another 5 before soft-landing, and so on. It's pretty funny actually, neither NASA nor RSA/Rosaviakosmos have the guts to do that sort of thing now (not that it would necessarily work out, either).

  • is miniaturization good or bad? (Score:4)

    by darkwhite ( 139802 ) on Monday July 23, 2001 @12:21AM (#67964)
    It's interesting how they regard the Viking probes as something gigantic and powerful(and, importantly, successful) as opposed to recent probes that are smaller and cheaper. But I don't think that smaller and cheaper is worse... it obviously reduces the impact in case of a failure. Moreover, I would reason that the instruments used in modern probes are lighter, cheaper, sturdier, smaller, more powerful versions of the ones used on the big old probes. And they made significant advances in a ton of other areas, they know more about where to look for failures, they have more powerful computers, transcievers (DSN I guess) and so on... so why is the faster/cheaper/smaller approach showing itself as a failure?
  • The Vikings were great spacecraft, there's no doubt about that, and the things that they discovered about Mars have been invaluble to planetary scientists over the past 25 years. However, the biology experiments on board the landers were just poorly thought out crap.

    Prior to the Viking lander touchdowns, the only spacecraft to touch down on mars was the Soviet Mars 3 mission which landed safely in 1971, only to have its computer lock up 30 seconds later such that no data was ever sent from the surface (D'oh!). All that was known about the surface was that which could be learned from orbiting spacecraft -- geomorphology, aeronomy, and the like, but certainly no chemistry. By sending generic rudimentary biology experiments to Mars without any knowledge of the chemical environment they would be operating in NASA set itself up for the rash of uninterpretable data that those experiments returned. In addition, the biology experiments for Mars were designed by astronomers, not biologists, and their focus reflects this.

    This failure has an important lesson to teach us about planetary exploration: don't get ahead of yourself. Before we can go searching for life, we need to do some basic science, learning about how a planet works before blindly looking for our version of life everywhere. Despite this, every NASA Mars press release mentions how Mars Odyssey, or MGS, or whatever new spacecraft will be looking for life, and that's too bad. At least the spacecraft themselves are better thought out, sent to address specific scientific problems and to teach us more about the planet Mars so that someday we CAN go look for life, but this time, we'll do it RIGHT.
  • No, they're just afraid of finding out that life on Mars is more intelligent than your president. Then again, that's not too difficult.

    Hacker: A criminal who breaks into computer systems
  • They've been looking, speculating, guessing and who knows what else and they found shit... There's nothing in our vicinity that we could find. Face it, if there is life somewhere it will have to find us, because with today's technology we're incapable to find anything usefull...

    If there was life somewhere else, they shouldn't bother to look something that is not carbon based. Silicon or whatever based life is right now as close as a warp drive... People speculate about it, you can see it in the movies and that's about it... :)

    Wait few decades, I hope things will change and somebody will find something or they will find us... If not, then this whole space is such a waste... *grin*

    ---------------
    I never wanted to go anywhere. I'm happy here...
  • So the real reason NASA doesn't look for life is they don't want to look dumb if they wrong? That's what I get from the article anyway...
  • Wouldn't that essentially be the test that Lavin performed? Though the boiling them would be within livable heats for some organisms, but according to the data, obviously not these ones.
  • However, there is no proof that other forms of life, such as silicon-based life, don't exist.

    Try getting an organic chemist to say "silicon-based life" with a straight face. And don't give me any crap about being open-minded -- take the classes yourself and you'll see why carbon is IT, baby.
  • most scientist took for granted that life needed oxygen, and a narrow range of pressure and temperature.

    err...scientists (and wine makers) have known about anaerobic microorganisms for a long long time. the process of fermentation is caused by microorganisms gaining energy from carbohydrates without using oxygen as a terminal electron acceptor. and you don't need to go to the bottom of the atlantic to find thermophilic bacteria either...you can find them in geothermal springs, where the water temperature can be routinely as high as 95 degrees celcius.

    no big surprises there...guess i've been trolled, haven't i?

  • Chimp with a british accent

    No, I don't think we are going to do that.


    Enigma

  • I must disagree with this. Certainly, NASA trumpets the news it thinks people will get most excited about. But what you have to realize is that NASA, as an organization, does not make these claims. The individual scientists, both at NASA and outside of NASA's immediate control, make claims that NASA then often announces.

    Personally, I think that claiming it is a ploy, sucessful for not, is overly cynical and does the scientists a disservice. There continues to rage a very hot debate over life on Mars, especially ALH84001. While the claims are perhaps extraordinay, they aren't wild or unfounded. The scientists involved have repeatedly gotten their analyzes published in peer reviewed journals (not run by NASA) and these papers are given due thought and credit by their peers. Many of us (myself included) do not feel that the data conclusively supports the claim that Martian life has been detected, but I know of no one who claims that these researchers are exaggerating their claims.

  • One failed because it crashed, it was landing in an area that hadn't been surveyed. Significantly, Viking DID survey the area before they landed, which is why they missed the July 4 target landing date.
    What mission are you talking about? Mars Pathfinder is the only mission that I know of that landed on 4 July (or tried to). And I wouldn't call it a failure by any means.

    If you're thinking of Mars Polar Lander, the area had been surveyed and the landing was targeted for late November or early Decemeber of 1999. I still haven't heard NASA give a conclusive explaination of the failure mode, yet.

  • How are you describing this as a crash or a failure? Perhaps I'm mis-reading your first post, but it seem to imply that you consider the landing a failure.
  • If you read carefully, you will note that the context of that statement was other scientists. Speaking as one of said, one who has read the major paper on both sides of the debate, I stand by my statment. Scientists disagree on the conclusions, but until you can point me to a credible scientist claiming that McKay et al. are intentionally exaggerating their claims (as opposed to reaching a different conclusion than others), I stand by that claim.

  • ...and a nice exercise in interstellar navigation...

    Interstellar navigation? Interplanetary, surely.

  • ...if they were there, they should still be there and thriving and easily found, even in the Martian extremes.

    A nice argument, with only one tiny flaw: all life found to date or theorized about requires liquid water, at least for a reaction medium if nothing else, and there isn't any liquid water on the Martian surface.

  • Small isn't necessarily beautiful when it comes to spacecraft. I'm a big fan of the "Big Dumb Booster" theory, which states that the cost of a space mission is related not only to the cost of fuel, resources and construction, but also to the amount of R&D that has to be done to create new technology for the mission.

    Using state-of-the-art technology incurs costs in R&D, since NASA has to justify its existence by contracting out to private companies and re-inventing the wheel everytime. I bet it'd be much cheaper to re-use the large and out-of-date Viking technology of 25 years ago than spend billions developing a bleeding edge spacecraft, but it'd do just as good a job.


  • Mars (Score:3)

    by marcovje ( 205102 ) on Monday July 23, 2001 @01:30AM (#67980)


    If you stack all papers discussing life on Mars on top of eachother, you can probably reach Mars ;_)
  • I'm sitting here with mod points, but since I don't see a 1, Grossly uninformed) pulldown, I guess I'll have to post some facts instead.
    until hot chimneys were discovered at the bottom of the Atlantic, most scientist took for granted that life needed oxygen, and a narrow range of pressure and temperature.
    Ever heard of anaerobic bacteria? I don't recall finding too many human digestive tracts [gu.edu.au] at the bottom of the ocean. Here's a few keywords for your Google search: methanogenesis, denitrification, sulfate reduction.
    Nowadays, we know that the organisms that live near the chimneys don't need oxygen, live in waters heated at 350 centigrades and seem pretty happy at pressures well over 100 atmospheres (they actually die when they're brought back to the surface due to the lack of pressure).
    And guess what? They're still carbon-based! [144.92.49.74]

    Non-oxygen-breathing does not equate with non-carbon-based.

    Please wait until you've finished your 10th grade biology class before making this proposal.

  • The most important Viking experiment (detecting life by degradation of irradiated earth-like nutrients) assumed that life over there should be carbon-based. However, there is no proof that other forms of life, such as silicon-based life, don't exist. As an analogy, until hot chimneys were discovered at the bottom of the Atlantic, most scientist took for granted that life needed oxygen, and a narrow range of pressure and temperature. Nowadays, we know that the organisms that live near the chimneys don't need oxygen, live in waters heated at 350 centigrades and seem pretty happy at pressures well over 100 atmospheres (they actually die when they're brought back to the surface due to the lack of pressure).

    Well, similarly, I see no reason why Mars wouldn't be teeming with life that's not carbon-based. A more definite answer to that question (and a nice exercise in interstellar navigation and precision landing) could be obtained by landing a probe right next to one of the Viking probes and seeing if some of the materials they were made of have been chewed at, or consumed, at a rate that's not explainable by natural phenomena.

  • Life on Mars is probably carbon based for two reasons:

    We believe that Mars might hold life because Mars is relatively similar to Earth. Correct me if I am guessing wrong, but silicon based life forms would live on a planet with higher temperatures.

    The second reason is the panspermia theory. Small molecules and pre-bacteria, not very much lifelike, are enough to push the chemistry between planets onto a certain path of evolution.

    ---

    Mars picture [msss.com] and Picture zoomed out. [msss.com].

  • The biological experiment was not bad, it is just that there were not enough different tests performed. It is interesting to see that nutrients were converted to gas prior to heating and then the conversion stopped after heating.

    Of course, there are non-life based ways to create gas through reaction: spill some water onto common Arm&Hammer baking soda and you get CO2 gas.

    The result of the nutrient -> gas test just begs for more testing. It does not rule life in or out.


    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ~~ the real world is much simpler ~~

  • I'll tell you why... (Score:3)

    by IKEA-Boy ( 223916 ) on Monday July 23, 2001 @01:47AM (#67985) Homepage
    I'll tell you why they stopped searching for life, they already found it. Or rather, it found us.

    For the last couple of years the martians have been sending their best specimens to earth to infiltrate into our governments. Just recently they booked an enormous success. They managed to get one of their top spies into the most powerful position on earth. Sure, he still has a speech impediment and he still has trouble with human logic but it worked! The humans actually bought it!

  • Re:Life on Mars is not necessarily carbon-based (Score:3)

    by at_18 ( 224304 ) on Monday July 23, 2001 @02:21AM (#67986) Journal
    However, there is no proof that other forms of life, such as silicon-based life, don't exist.

    Maybe silicon-based life can exist, but the strongest argument against it is the fact that here on Earth, with a lot more silicon than carbon, we developed a carbon-based life. If a silicon-based one was possible, Earth was the perfect planet for it.
  • Think about it. Increased government funding comes from success (or really, really, spectacular failure). It doesn't come from admitting you were wrong about something (well, unless you're the FBI). Now, it cuts both ways: if they said they found life and later had to retract that statement, they look just as stupid as if they had to say the opposite. Their "best" course of action is to keep with the story they first gave (i.e. there is no life on Mars).

    Kierthos
  • Considering how low on the government funding totem pole NASA is, I wouldn't be a bit surprised to see them hype anything to get money out of GWB.

    Of course, if they could "develop" a space death ray that takes out incoming missiles, then they could probably ride that pork-project all the way to the end.

    Kierthos
  • I have to wonder... if it hadn't been for that one Star Trek episode (the one with the Horta), would anyone say "silicon-based life" with a straight face? Because that's, as far as I can figure, the first place I ever heard it. (Of course, I haven't read every last bit of science fiction, so it's possible/probable that Rodenberry was ripping it off from somewhere else.)

    Kierthos
  • I don't. The Russians had an amazing track record of blowing up their own spacecraft or having other spectacular failures. Notable points include the Oct. 24, 1960 explosion of the R-16 ICBM in Baikonur (which was pretty much hushed up for 3 decades), the July 14, 1968 explosion of the Proton launch complex, multiple failures of the N1-L2 rockets either at launch or shortly thereafter in 1969, and the Salyut space station not reaching orbit due to Proton rocket failure in 1972. The Cosmos-557 space station would fail in orbit the next year. (Mir would not get launched until 1986.)

    But, they were also logging some successes, including the first probe to enter the atmosphere of Venus (Venera-4 - June 12, 1967), the Venera-7 lander sending data from the surface of Venus in 1970, and so on.

    Kierthos

  • Re:Better hardware 25 years ago? (Score:3)

    by Jagin ( 243283 ) on Monday July 23, 2001 @04:06AM (#67991)
    No no.. its just that there was more national pressure back then. It was seen as real important. Thus more money, more brilliant people.. that sort of thing.
  • Everytime I read another one of these "Life on Mars" articles I wonder if it isn't a NASA conspiracy to keep the public interested in space exploration and thus keep the dollars flowing (from Congress). Seems that everytime I turn around there is there is some new controversal space story (i.e. space tourists, life on mars etc etc).
  • If slashdot is my only connection to other human beings, does that qualify me as a silicon based life form?
  • > ...multiple failures of the N1-L2 rockets either
    > at launch or shortly thereafter in 1969, and the
    > Salyut space station not reaching orbit due to
    > Proton rocket failure in 1972.

    Let's not forget the mid 70's when they launched that stupid Venus probe that crashed back onto earth and the Real Steve Austin had to stop it before it killed millions.

  • Actually, the large organisms all need oxygen.

    Also, scientists were well aware that some bacteria not only don't need oxygen, but are killed by it. Those bacteria can be a problem in canning if you aren't careful.

  • > Of course, we could always find a planet
    > populated by robots a la Transformers....

    Nah, we already have bombs that can punch through thirty feet of steel-reinforced concrete before even exploding. A few feet of steel ain't jack squat. A walking aircraft carrier will be dead in minutes in a war. At least sea vessels protect important things below the water line and have defensive Vulcan guns and whatnot.

    Transformers, Ultra-Man, Johnny Socko's flying robot, Godzilla, Mech-Streisand, they'd all be dead within a half an hour of walking up on the shores of New York or Tokyo or Southpark, CO.

  • For crying out loud, 11% of the adult population in this country doesn't even understand the world is round like a ball and not round like a flat pancake.

  • Also sprach JBowz15:
    Hard to believe that it's already been 25 years since Leif Erickson and his Viking pals first came to North America.

    Of course, they landed way up in what is now the Canadian great white north, so it is not too surprising that no signs of life were found.

    Well, they did land on a Tuesday night, so finding no signs of life is no surprise.

    FWIW, I worked at NASA for 2.5 years and never once did I see intelligent life there ...

  • Back then, NASA was about space exploration. Most of the people working there were scientists, programmers, engineers, data archivists, etc.

    Nowadays, most of the people at NASA are bureaucrats. Thus they add expense without expertise, knowledge, or usefulness.

    ...

    Okay, that was a cheap shot and was unfair. The cumbersome, vapid bureaucracy is only one of the problems, but it's a big one. By and large, one good bureaucrat can replace twenty average ones and be more effective because the one good bureaucrat knows how to get out of the way and how to shield the techies from the idiocies of other bureaucrats. This is true in business, government, education, charities, wherever. The only problem is, in government, you can't be fired for incompetence. ("The thin end of the wedge." - Yes, Prime Minister)

  • Luckily we figured out a way, after eight years, to make her powerless and impotent by getting her married to James Brolin.

  • Why would the government look for life on Mars? Why, so the IRS could tax it, of course! (They're doing it for the kids, really.)

    Though I agree about silicon-based life. Carbon is far more common in our galaxy and solar system. Carbon is more chemically active, ie more likely to bond with hydrogen, oxygen, etc. (I know there's a term for that and I can't think of it for the life of me.) Also, carbon-carbon bonds are tighter than silicon-silicon bonds. So while silicon-based life is possible, it's highly doubtful. Where conditions exist to make silicon-based life possible, carbon-based life will be more probable.

  • How do you design a test for life that is all-encompassing? Isn't it arrogant to assume that our definition of life (that which revolves around our ball of dirt) is the only definition? What about a silicon life-form? We are designing tests for carbon-based life, tests for earth life.

    Only if we use your definition of arrogance.

    What kind of test could we send to detect microbial life that diesn't meet our definitive tests?

    If we don't use definitive tests, how will we know whether the answers are any good? What would you do? Drop some aluminum siding on the surface to see if there is an overwhelming need for martian life to bond to it?

  • Well, I guess you've got to compete with someone to stay motivated. With the Soviet Union out of the picture, NASA just competes with itself instead. That probably wouldn't be so bad, but I'm sure that the internal competition pulls in random directions instead of directing everyone towards the same goal. Good managers would figure out how to channel all of that natural tension in a productive manner; right now it is just being dissapated.
  • "Life on Mars" conspiracy originated from rocks found in Antarctica, not NASA. "Space tourist" conspiracy originated from the Russians and Tito, not NASA. Now, the "JFK" conspiracy, that's where you should look at NASA.
  • to think of how incredible NASA used to be as compared to what it's like now. I don't do any work related to NASA but from everything I've heard, and this article supports it, the agency has been getting less and less... I don't know, radical (I mean that in a good way) in its approach to problems. This is not really the fault of the scientists working there, funding is much smaller than it used to be and the government is seeing NASA as less important than it used to. Some would say that the money could be spent in better ways but I fully support NASA and its foreign equivilents. It's a sad day when a NASA scientist says that we attempt fewer things with each project.
  • just because life was found around volcanic vents doesn't necessarily mean that it originated there. we live on a planet thriving with life (especially the oceans) , and as we all know life tends to find its way into every conceivable nook and cranny that exists on this planet... So while I find life around thermal vents intriguing, I'm skeptical about it originating there...
    --
  • Finding conclusive proof of life on Mars would cause a huge, HUGE change in the is country and all over the world concerning the need and worth of the space program. On the other hand, having lots of fanfare and parading about that you will test for life, but then fail to find anything will cause more backlash and disgruntled Americans to wonder why we are hurling things up into space when, by all rights, we could be thinking about the children.

    Probably the best solution, and I think this may have been happening all along, would be to do preliminary tests in secret, maybe by seperating a 10 part test into 10 different missions, where they would never be discovered by the press, but that could help them determine whether or not they should go balls out on another test for life.

    Of course I am pulling this out of my ass, but at the same time NASA has become less of a science endeavor and more of a PR firm. They still do some science, but in order to justify it to the public, it has to be sexy.

    ...just my 2 cents
  • Comment removed based on user account deletion
  • Problem is that no-one can come up with any kind of chemistry which can be as complex and varied as carbon based organic molecules.

    However, just because nobody has come up with it yet, does not mean it isn't possible. 400 years ago, people surely thought they were on "the cutting edge", that they "knew" so much about the world around them. Compared to what we now know, we can look back and laugh our collective asses off at many of their theories and "truths".

    In a few hundred years, we will be the ones being laughed at.

    Given the course of history, it's silly to completely dismiss an idea based on what we currently know. This is not to say we should spend millions on research of fanatical ideas, only that we should recognize the fact that there is likely much more to this world than any of us could imagine.

  • Ah, memories.... (Score:5)

    by JBowz15 ( 451573 ) on Monday July 23, 2001 @12:20AM (#68010)
    Hard to believe that it's already been 25 years since Leif Erickson and his Viking pals first came to North America.

    Of course, they landed way up in what is now the Canadian great white north, so it is not too surprising that no signs of life were found.

  • My former adviser was telling me about an experiment that's planned to fly on some future Mars probe: they're collecting DNA samples from representatively diverse lifeforms which they will tag with a fluorescent marker and bring to Mars in something like a microwell dish. Then when it gets to Mars the probe'll toss in some Martian soil (no doubt processed in some way) and see if any of the DNA hybridizes by measuring the fluorescence.

    Obviously this won't find any really weird organisms like something silicon-based (which is at least theoretically possible, see Genetic Takeover and the Mineral Origins of Life by A. G. Cairns-Smith) but it could confirm the panspermia hypothesis (Mars->Earth or Earth->Mars); and even if there was no direct relationship between Earth and Mars life, there would be some level of hybridization as long as Martian life used DNA (or a closely related analogue).

    So although the bulk of the focus now is on looking for more general life-conducive factors like liquid water, past atmospheric composition, and temperature history, there's also some attention to specific tests for life, even if they are expected to fail.

  • NASA has solid intentions (Score:5)

    by deathcow ( 455995 ) on Monday July 23, 2001 @02:12AM (#68012)
    NASA probably probably appreciates anything that raises public awareness about space and planetary exploration.

    Look at all the Mars stuff happening - Mars in the Media [imdb.com], and the immediately recent Mars opposition [stsci.edu] and new hubble shots [stsci.edu], the killer success of the surveyor mission [nasa.gov], the probes [nasa.gov] heading there right now, the rover mission and others [nasa.gov].

    NASA should be pimping the hell out of it. The existence of extraterrestrial life, even microbes, is a question of enormous magnitude. It is truly a question of biblical proportions. NASA's work on Mars could perhaps unravel one of the greatest mystery humans face. [nasa.gov] It will be very interesting to discover what is returned to Earth in the Mars soil samples [nasa.gov] returning to Earth in 2005. You can check out the strategy paper [nasa.gov] NASA issued on researching Mars exobiology.

    The ultimate mystery!

  • Long ago, I remember reading a story by some Russian author where the good Soviet cosmonauts met up with *FLUORINE* (see note) based life.

    Note: They used Fl instead of O2 in their respiratory systems.
  • I knew I'd heard something like that quote somewhere, but I'd no idea where :)

  • Intelligent life (Score:3)

    by Richard Bannister ( 464181 ) on Monday July 23, 2001 @12:39AM (#68015) Homepage
    Isn't the best evidence that there is intelligent life out there the fact that it hasn't contacted us? :)
  • It also might be possible that something which would classically be considered alive (self-sustaining, consuming resources, locomotive, etc...) could exist in an equilibrium system. Just because life may cause a non-equilibrium system doesn't necessarily mean that it must.
  • Has anyone out there read The Andromeda Strain? It certainly made me think about how we define life. I can't recall the criteria given in my Biology textbook, but I'm pretty sure that carbon-based was not a requirement. Let's see: 1)Able to reproduce; 2) Metabolism (uses energy); 3)Made up of cells [who says life on another planet will use cells?]... There are more characteristics I'm forgetting, but you get the idea.
  • Put me up for the next trip to Mars. I have been using seti@home for years, but this might be the time we finally finds some life in the universe.

    If it's wet, Drink it! [spitzy.net]
  • Welcome to the language of science, where nothing is ever known for a fact. Not only do I think that NASA releases information to the public in an attempt to raise funding, but I also believe some of their missions are primarily about fund raising. Unfortunately I think it's necessary, since the public doesn't want to be bothered by taking the time to learn how much can be gained by funding NASA.
  • Heh. It would prove extraterristrial life to be unintelligent if it contacted us. I mean...just think of the phone bill!

    Phoenix
  • The US government is afraid of finding out that life on Mars is more intelligent than life on Earth.

    Phoenix

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