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Mars Space Science

Protecting the Solar System From Contamination 121

Posted by Soulskill
from the life-will-find-a-way dept.
tcd004 writes "An article at PBS begins, 'Imagine this crazy scenario: A space vehicle we've sent to a distant planet to search for life touches down in an icy area. The heat from the spacecraft's internal power system warms the ice, and water forms below the landing gear of the craft. And on the landing gear is something found on every surface on planet Earth... bacteria. Lots of them. If those spore-forming bacteria found themselves in a moist environment with a temperature range they could tolerate, they might just make themselves at home and thrive and then, well... the extraterrestrial life that we'd been searching for might just turn out to be Earth life we introduced.' The article goes on to talk about NASA's efforts to prevent situations like this. It's a job for the Office of Planetary Protection. They give some examples, including the procedure for sterilizing the Curiosity Rover: 'Pieces of equipment that could tolerate high heat were subjected to temperatures of 230 to 295 degrees Fahrenheit for up to 144 hours. And surfaces were wiped down with alcohol and tested regularly.'"
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Protecting the Solar System From Contamination

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  • by Press2ToContinue (2424598) * on Wednesday March 06, 2013 @07:11PM (#43098685)

    will the Office Of Planetary Protection will provide condoms in which to encase the astronauts?

    • by dgatwood (11270) on Wednesday March 06, 2013 @07:37PM (#43098989) Journal

      Depends on whether they're down with OPP.

    • Actually, when two isolated human cultures meet, one of the first things trade are sexually transmitted diseases. The same thing will happen with aliens:

      "Captain, I know it was against orders . . . but I just couldn't resist her green scaly skin, her soft yellow underbelly, and her series of fin-like ridges running down here spine!"

      • by Anonymous Coward

        You and I have similar tastes.

      • by maroberts (15852)

        Actually, when two isolated human cultures meet, one of the first things trade are sexually transmitted diseases. The same thing will happen with aliens:

        "Captain, I know it was against orders . . . but I just couldn't resist her green scaly skin, her soft yellow underbelly, and her series of fin-like ridges running down here spine!"

        Dr McCoy calling James T. Kirk to the Medical Bay - again!

      • Does the word rishathra still exist?
  • by Kenja (541830) on Wednesday March 06, 2013 @07:14PM (#43098713)
    we're already here.
    • I don't see how it's a bad thing to seed life on a lifeless planet. We could take a lifeless planet and in a few hundred million years complex life forms might evolve. This is bad how? I thought life is a good thing.

      Actually, thought experiment: If it's "better" to keep a planet lifeless and dead instead of seeding it with life, then wouldn't it also have been "better" if Earth had remained lifeless and dead?

      • We could take a lifeless planet and in a few hundred million years complex life forms might evolve

        'Correction', I mean also, moons, e.g. Europa is one candidate.

        As far as we can tell, life is precious and valuable in this universe ... to inherently call life "contamination" smacks of some very broken way of thinking. If we see ourselves as "contaminating" other planets by colonizing them, then it is only logical that we must exterminate ourselves on Earth too, as we are a "contaminant". That would be sil

      • Yes, IF that planet really is lifeless. A single tiny non-terrestrial colony of bacteria would answer some of the biggest questions in biology and xenobiology, you have to know you've not infected the planet to use that data.

        Genesis is a wonderful power, but you've got to make sure you don't overwrite an existing matrix for the science to be any good, even if it's only a Ceti-Alphan earslug.
        • Yeah, but we already don't really "know", due to meteor-based seeding that has been going on for a long time. I agree it is of course prudent to at least check for existing life before attempting to seed life (the summary implies a lifeless body as a contextual premise here).
        • Of course, if we do seed life (and ultimately intelligent life) on other planets, we should leave them with some really confusing "guide-books" explaining their origins, as a prank.
      • Yeah, maybe nature made us intelligent and able to build spacecraft precisely to spread life further from Earth. Maybe that is how life on earth originally came to be.

      • You are missing the point. We aren't trying to keep a dead planet dead, we are trying to keep it dead long enough so that we know it WAS dead. The equipment we currently can send out now, can generally only tell us if there is life, and some basic details about it. So if we accidentally seeded the life, we would have no way of knowing if the discovery was 'real' or not.

        However, there are some very good reasons to not want to contaminate a planet. What if you were trying to evaluate the chemical composit

  • Already done (Score:3, Interesting)

    by able1234au (995975) on Wednesday March 06, 2013 @07:19PM (#43098763)

    Meteors from earth have probably peppered the other planets anyway. Some bacteria spores can survive inside them. So they are probably already contaminated. And in any case we could compare the DNA to see if it is from earth.

    • If we could examine its DNA with any of our advanced tools, we will know it came from earth before we get around to doing any sequencing.

      Though there are good reasons that DNA might be used in other biogenesis events, there is no particular reason that the bases our DNA uses would also be used.

      • Re:Already done (Score:5, Interesting)

        by garyebickford (222422) <gar37bic AT gmail DOT com> on Wednesday March 06, 2013 @07:56PM (#43099209)

        IANA physical biologist, but I did look into this question a bit from a systems point of view a few years ago. The key thing would be the minimizing of the energy required to sustain the structure while at the same time allowing maximal adaptability. Or, more abstractly, the 'fitness' of each amino acid pairing for the general task.

        There is certainly a large element of chance, but it's probable that the four amino acids that ended up being used are pretty close to the optimal set. This derives from a general evolutionary model, where various things happened by chance, and the ones that worked best for the situation (I could have said 'survived' but that carries too much baggage) would tend to be the ones that were incorporated.

        Otherwise, one is arguing that a single chance pairing of amino acids just happened to work, and no others were (in an analogous sense) 'tried' in the right conditions. To my mind, it's more likely that many combinations came together, and one was more successful. It might even be that there was a sequence of such cases - maybe (hypothetical example) when the G and C bases bond together, they float better in a solution with a pH of 7.2 or some such thing.

        I prefer to think that certain bases were more available, or just happened to work better under the conditions, and so they got used while others that were 'almost as good' didn't, or didn't for very long. In this case (again with little biological background), things like requiring just enough energy to be split apart, or fitting just right together with the splitting mechanism, or any of several other criteria including environmental ones such as 'in this temperature and pH range') would all be factors. I suspect some very interesting analysis and experiments could be done on this.

        • Re:Already done (Score:5, Informative)

          by the biologist (1659443) on Wednesday March 06, 2013 @08:39PM (#43099677)

          As my handle suggests, I am a research biologist. Mostly, that just means I like to think about this sort of topic. Don't take it as me attempting to shut you or others down.

          Your logic is more or less on the ball... DNA isn't made of amino acids. There are plenty of other nitrogenous bases which could have been used in DNA without any other complications. The paired bases do have to match up in a consistent way. Various forms of synthetic DNA has been made with alternate bases and it seems to behave like DNA in a physical sense.

          I too prefer to think that the bases our DNA use has do do with which ones were most readily available, or which were most available in the little puddle where the biosystem started. Those basic organisms which started later or used things 'almost as good' got eaten in the endgame.

          Similar logic comes in to play with the amino acids which we use to make proteins. There are many alternatives, several of which have been experimentally introduced into living biosystems. (There are E.coli which now use amino acids not found in any natural biological system; labs at University of Texas-Austin study this topic.) With amino acids, there is even more room for random chance in the initial choise of basic modules. Once that first living system started, it probably ate every other nascent living system. There is good reason to believe that amino acids will be used to form proteins and that a certain diversity of amino acids is needed, covering several basic chemistries, but that the specific amino acids isn't so important. (The E.coli types with chemically novel amino acids grow just fine.)

          • Once that first living system started, it probably ate every other nascent living system.

            That reminds me a bit of Microsoft. DOS and 16 bit Windows weren't actually very good. However they could run on cheap 8086 and 80286 hardware. Unix really needed an MMU and only really worked well in flat mode, both of which needed a 80386 or later. MS got DOS and Windows out into the market relatively early. They had very good relations with "Developers! Developers! Developers!" too. So most of the world end up with a box running an OEM copy of Microsoft Windows because the hardware was cheap and the soft

    • by Shavano (2541114)
      This is a real longshot. First off, rocks on Earth typically don't have a lot of bacteria in them. Second, the kind of shocks that could splash Earth stuff into space are... extremely rare. Third, most bacteria could not survive decades to centuries in space. Fourth, very little such material could end up on orbits that intersect other planets. Fifth, it would then have to survive the final crash and find itself in a hospitable environment.
    • by wvmarle (1070040)

      And that is exactly one of the theories on how life started on earth: seeded by meteors carrying alien lifeforms.

      So now we can add another theory to the origins of life: bio-contamination left behind by alien visitors.

  • by Anonymous Coward

    There are people stating we may have put Streptococcus on the moon. There is no one qualified to begin to tell us how a organism from a unknown planet might work. The reality is the best we have is guesses. 295 degrees Fahrenheit is no wear near the flash point for many living organisms and their progeny. The only safe way is to quarantine permanently everything off planet, until the time needed to research all these possibilities has been done. This may mean life appointments to quarantined research

    • by hawguy (1600213)

      There are people stating we may have put Streptococcus on the moon.

      This is in dispute - many say that the camera was contaminated after its return on earth.

      There is no one qualified to begin to tell us how a organism from a unknown planet might work. The reality is the best we have is guesses. 295 degrees Fahrenheit is no wear near the flash point for many living organisms and their progeny. The only safe way is to quarantine permanently everything off planet, until the time needed to research all these possibilities has been done. This may mean life appointments to quarantined research areas for off planet exploration employees.

      I've never heard "flash point" applied to microorganisms - how does one determine the flash point of a microorganism and how does that relate to its survivability on another planet? Does the progeny of an organism have a significantly different flash point from the original organism?

  • Two centuries ago exploring ships did the same thing (so they thought) anti-rat boards on ships; fumigants etc. but rats still found their way on board, and go off when we got off. Anyway the bacteria we might find could be common across the galaxy.
    • by Anonymous Coward

      Pieces of equipment that could tolerate high heat were subjected to temperatures of 230 to 295 degrees Fahrenheit for up to 144 hours. And surfaces were wiped down with alcohol and tested regularly.

      You're comparing apples to bananas. They knew very well how effective their anti-rat measures were, just as we know very well how our antibacterial measures are. Just because something analogous to what we are doing today failed two hundred years ago (and people even knew it didn't work) doesn't mean what we are doing today will also fail.

      • by garyebickford (222422) <gar37bic AT gmail DOT com> on Wednesday March 06, 2013 @08:07PM (#43099357)

        I think the analogy stands. Consider the tardigrade, an animal composed of 40,000 or so cells (every adult has the exact same number of cells). They have been shown to survive freezing to near 0K, heating to over 130C, and the radiation and vacuum of space outside the ISS (or was it the Shuttle?).

        The point is that for a given potential infestation, the bugs only have to succeed once. Sterilization measures have to be 100% successful every time. And they aren't, can't be and won't be. Even if we never actually put humans into space again, every vehicle will contribute it's little pile of DNA. Each halving of the number of impurities left on a surface increases the cost, difficulty and effort by an order of magnitude. (hmm - this is much like the 90% rule of software!)

  • by Anonymous Coward

    Sure, for the first few missions go ahead and sterilize the bacteria. But once it's been pretty well established you're looking at a ball of rock and/or ice, just let the bacteria grow. See if life from Earth can grow in other climates. It might actually help to understand the variability of conditions for sustaining life a whole lot better than aiming a telescope into space and measuring the X-rays and infrared light for Earth-like conditions.

    • by hawguy (1600213)

      Sure, for the first few missions go ahead and sterilize the bacteria. But once it's been pretty well established you're looking at a ball of rock and/or ice, just let the bacteria grow. See if life from Earth can grow in other climates. It might actually help to understand the variability of conditions for sustaining life a whole lot better than aiming a telescope into space and measuring the X-rays and infrared light for Earth-like conditions.

      How do you determine that with any certainty? We're just now drilling deep underground into a sealed antarctic lake that may contain bacteria that's been living there for thousands of years.

  • It's tempting to conclude there's nothing living on Mars, so why not colonise it it with some custom-engineered stuff.
    I would love to believe the SciFi stuff - imagine that by the time we have just about finished destroying Earth, Mars will be waiting for us with an atmosphere full of oxygen, and unlimited meat and veg for all. Ah yes, and the benevolent bugs that turned rock into water are totally not going to mutate into anything that kills you.

    Since we've managed to screw up all of the unique ecosystems

    • by viperidaenz (2515578) on Wednesday March 06, 2013 @07:49PM (#43099125)

      First you need to give Mars a magnetic field to shield it from the radiation given off by the Sun, which also strips off any atmosphere that accumulates too. It's also pretty good at killing things too.

    • We're rapidly approaching the point (assuming we're not already there) where a well-funded small group will be able to send a tailored package of bacteria to Mars and start trying to terraform it, with or without the permission or knowledge of the rest of the human race.

    • IMHO, from the perspective of the solar system, we are 'life'. There's no evidence of life anywhere else in the solar system. If so, then where we go, we bring 'life' with us. We are the carriers of that seed. So in that sense, we are the fruiting body of the biological entity called 'Terran Life'. It has taken a billion years to develop its fruit, with the capability to carry itself to other soils.

    • Any life that is or may have existed on mars at any point in the past is almost certainly already related to life of earth. Either mars seeded earth or the other way around. We'll never know... and if we find life on mars we'll never be totally sure it wasn't some mutated form of bacteria that came off a probe in the early stages of the space program. Because, like I said, it's almost certainly going to be very earth like. How long can you keep mars sterile for? It's the only planet in the solar system that

    • You're worried that we can "screw up" a sterile (i.e. lifeless) environment? What does that even mean? If it's sterile, then by definition there is nothing and nobody there to harm - just lifeless dirt, rocks etc. And so who does it benefit to keep it sterile? Do the rocks or dirt benefit?

      If introducing life on to a planet is "bad", then shouldn't you be arguing that we wipe out all life on Earth too? Or is that actually what you're arguing?

  • It's a variation on Peace on Earth or Purity of Essence or Office of Planetary Protection. Mad as a bloody March hare!

    It's incredibly obvious, isn't it?

  • many types of Clostridium and tetanus bacteria can take 90 percent alcohol solution for *hours*

  • by WizADSL (839896)
    I love Star Trek, but this isn't Star Trek. Although we should prevent accidental contamination of another ecosystem, I don't think we should freak out if it happens. Natural cross-contamination (meteors, etc) stand a good chance of being the reason there is life here on Earth.
    • It's not so much Star Trek non-interference as it is good science. To use the example given in the summary, we land a probe on some icy world which melts the ice. We infect the place with bacteria on the landing gear. We then take samples and find--surprise surprise--bacteria!

      Well, gosh, what did we learn? We can't really say if the bacteria--which looks remarkably like bacteria found on Earth--was native to the planet or that we just brought it along with us. So this $500 million probe doesn't answer

  • As astronomer Dr. Hugh Ross noted, sending a probe to Mars to search for life is pointless if that probe is not programmed to both recognize and ignore earth-based life because our planet "contaminates" the other planets down-solar-wind from us all the time. Indeed, spores and whatnot are able to waft high enough into our atmosphere to be caught by the solar wind and taken into space, to land who knows where.

    • by hawguy (1600213)

      As astronomer Dr. Hugh Ross noted, sending a probe to Mars to search for life is pointless if that probe is not programmed to both recognize and ignore earth-based life because our planet "contaminates" the other planets down-solar-wind from us all the time. Indeed, spores and whatnot are able to waft high enough into our atmosphere to be caught by the solar wind and taken into space, to land who knows where.

      But how would you know if the spore originated on earth, or it originated somewhere else and colonized the earth?

  • They should be loading their rovers and satellites up with as many forms of bacteria and simple life forms as they can. We should be encouraging spreading life as much as possible. It might not effect us now but millions of years from now we could have planets in our solar system with lots of carbon based life and atmospheres more hospitable to humans so when we eventually destroy the Earth we have a few fallback plans.
    • You've been watching too much sci-fi.

      It took ever a billion years for early life to produce enough oxygen to saturate the oceans and make its was in to the atmosphere. You also need liquid water on the surface for that to happen too, which requires enough atmospheric pressure and the correct temperatures.
      If Mars could sustain an atmosphere, its a possibility. Venus and Mercury are too close to the Sun and all the other planets are too far.

      • by detain (687995)
        It doesn't have to wind up being an atmosphere thats really compatible with human life but life in general would be good, and I acknowledge millions of years might not be enough time, but I don't see humans lasting on earth more than a few million more years at most .
  • life finds a way.
  • So if they wipe some parts of the craft with alcohol why do they bother heat blasting the rest of it? I assume because heat blasting is better. Which means that some of the craft is bacteria free and the rest isn't. So... what was the goal again here?
    • It's not sufficient to stop: "OMG there's alcohol breakdown residue on the surface of this rock! That's organic! It must have been from the same life that made that chunk of plastic!"
    • by wvmarle (1070040)

      Not all the parts can withstand the heat so well. And even heat blasting is not guaranteed to make it all completely sterile, as there is always the outside of the craft that remains in touch with the atmosphere. There are always ways for bacteria to sneak in after all. All they can do is try to make it as hard as possible for germs to get in, and after that make it as hard as possible for those that do, to survive.

  • What effect, if any, does constantly being bombarded by ionizing radiation while in space transit have on sterilization?

  • our hitchhiking overlords when they return to Mother Earth.

  • Does it really matter whether the life comes from Earth or is native to the planet/moon? Wouldn't the more important discovery be the proof that life could actually survive there?
    • Depends on what you're looking for.

      The immortal question is, "Are we alone in the universe?" Well, to begin answering that question, we have to determine whether or not there is life out there--any kind of life. If we send a probe out to Mars or Europa or a comet or some such place and we look for life and we find it, how do we tell whether or not it was there before us or if we brought it with us? So it makes it hard to tell whether or not the solar system is teeming with life because we brought it ther

  • nuke the landing site before and after arrival.
    • by rubycodez (864176)

      may not be effective, some bacteria can take massive dose. if 800 rem can kill a human, 90,000 a cockroach, consider that some bacteria can take 3 million. of course, there are fragile ones that are killed at 100 rem too.

  • We can't even prevent cross-contamination from occurring here on Earth. The commercial overseas shipping industry has introduced countless, destructive, invasive species into other ports that wreak havoc on the local ecosystems - and have the potential to impact local economies. Off-planet is not going to be any better; spreading Earth dust is unavoidable. As Jeff Goldblum said in Jurassic Park, "Life.... finds a way." I say give it an honest effort, but don't dwell too long on attempting to thwart the inev
  • So if someone loads a computer virus onto Curiosity, it might spawn robots on Mars?
  • If there was life on another world I would suspect that it would operate on different mechanisims, you wouldn't have the same DNA structure, it would have different protein's, ect. I would be more concerned that our life would wipe out the alien life or vice versa.

  • If there is no life there already, why no contaminate it with life, get something started there. As long as there is no life there already, it does not violate the prime directive (according to my copy of Starfleet manuals). I cant seem to see the harm in it.

    • If there is no life there already,

      "If". That's the question. We don't know. And we can't find the answer if we slime up the test subject before we even run the test. It's about trying to avoid contaminating our samples with the very thing we're looking for. (Imagine if you were an oil surveyor looking for signs of oil, but you were randomly leaking oil everywhere you went.)

      Once we know for sure that a body is lifeless, then yes, go nuts.

  • So nice to know that we're now catching up to science fiction from 40 years ago.
  • by Vitus Wagner (5911) <vitus@wagner.pp.ru> on Thursday March 07, 2013 @12:20AM (#43101335) Homepage Journal

    Oh, these engineers only need a slightest exuse to get some alcohol by taxpayers money. They would indeed test it regularily. Because they know that contamination might happen only in the imagination of bad pulp fiction writer, and alcohol has a much better uses than to spill it onto the rover.

  • Pretty sure there were a bunch of little Tardigrades [wikipedia.org] stuck on rocks that have been blasted off the surface of Earth at some point and end up roaming around the solar system waiting to crash somewhere. They are likely to have been around for many hundreds of millions of years.
  • I'd be more afraid of intelligent extraterrestrial life extrapolating our location using the trajectory of our spacecraft.

  • Ha!

    That's the end of you, then, Earth-invading Martian Scum [wikipedia.org]!

  • "230 to 295 degrees Fahrenheit"

    I know that 1000 F was defined as the temperature of the king of france's lit fart, so it's about a quarter of the temperature of a lit fart.?

Hacking's just another word for nothing left to kludge.

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