Protecting the Solar System From Contamination 121
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.'"
And in the future... (Score:4, Funny)
will the Office Of Planetary Protection will provide condoms in which to encase the astronauts?
Re:And in the future... (Score:5, Funny)
Depends on whether they're down with OPP.
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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!"
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You and I have similar tastes.
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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!
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Oh it's bad alright. (Score:2)
It's the places that might already have life that we are trying to preserve. So that if they do have alien life, we can detect that life and do science on it.
Demonstrably dead things we don't care about getting life all over them. You can splash as much bacteria as you like on the Moon, no one cares. Asteroids? Go nuts. Life away.
But Mars, Europa, Titan, and comets; we wait until we figure out how to definitively rule out native, alien life.
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Unless there's profit to be made. To hell with everything, if there's profit to be made.
Too late... (Score:3)
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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?
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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
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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.
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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.
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>nature did not make us anything with a specific purpose
Maybe not, but evolution did grow legs and wings and thereby empowered life to expand to ever new territories. I don't see brains and spaceflight being any different in the context of life/nature "wanting" to expand.
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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
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If life does not exist anywhere else in the universe, the universe doesn't care.
It may be a waste of a good opportunity, but even "life" doesn't care. Except us, and maybe the dolphins.
So, as the only species capable of having an opinion, it might be a "crime" against humanity to... well, not do whatever we decide is the humane thing to do. If we decide not to pollute the universe with ourselves, then that decision is life's "natural will". If we decide to spread life far and wide in a hostile cosmos, then
Already done (Score:3, Interesting)
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.
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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)
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)
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.)
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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
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Re:Already done (Score:4, Interesting)
That is one of the things they're testing. They see an initial growth defect upon adding the new amino acid. Basically, every place the altered codon is found the resulting protein acts somewhat weird. Biology is flexible and the cells keep going anyway. After a short while, the cells get over the issue one way or another and there is no remaining growth defect apparent.
[A different experimental group...] If you have an ongoing culture and take isolates at incremental time points, the isolates show interesting behavior when compared. Each isolate will outcompete the isolate just prior when in a common culture, as expected. If you compare each isolate to the second back, most (but not all) will win. If you compare each culture to earlier isolates, it is essentially random which one will win. The expectation was that each isolate would outcompete all prior isolates...
The modified cells will lose to normal ones after the initial change... but once they have had time to get over the shock, it then becomes anyone's guess which way any particular competition experiment will go.
I think the group modifying amino acids is looking to convert them all to types not found in nature... resulting in E. coli with no natural amino acids. At that point, things start to get real interesting. Lots of aspects of our biology are tuned in some way to deal with the existing distribution of amino acids, so these highly modified cells will have lots of changes to lots of systems. Evolution is a really powerful thing. Once you start feeding the culture with less and less of the new amino acids, the cells will figure out how to synthesize them and do so efficiently. Some metabolic circuits will be tweaked, others will be scrapped and scrambled whole-sale.
Re:Already done (Score:5, Informative)
Actually, you should read up on the topic before you go spouting nonsense.
Transfer of Life-Bearing Meteorites from Earth to Other Planets [arxiv.org] for example.
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You may be the one spouting nonsense given that the topic of this discussion is "Protecting the Solar System From Contamination" and the paper you quote says
"For every object, the number NA and NB are much greater than one. Although
it is uncertain how rocks enter the presumed sea under the surface, for example,
of Enceladus and Europa, the probability may be high that micro-organisms trans-
ferred from Earth would be adapted and growing there."
I'll accept your apology, thanks. Next time make sure you read wh
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Ummm? The guy was stating that meteors couldn't go from earth to the other planets... I pointed out that they indeed can...? There is a whooosh in here somewhere, I am just uncertain where it is at the moment. I think we are reading the OP in different ways...
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woooooops... my bad. Mr AC's comment was hidden to me, so i thought you were replying to me. OK, my apologies to you instead :)
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reality check:
Life is a long shot. First off, blah blah blah, and then it would have to evolve into humans.
And it did and so it can.
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4.5 billion years.
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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.
No one on this planet (Score:1)
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
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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?
but rats still got every where (Score:1)
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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.
Re:but rats still got every where (Score:5, Insightful)
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!)
Re:Why bother? (Score:4, Interesting)
Ok, I'm not a complete nutjob here, and I understand two parts of why they bother, first the agency is there to protect our own planet from samples coming back: if the moon or Mars supported life for a few billion years it might become horribly invasive when brought back into the paradise that is our planet, so there is that. Second, they don't want a bacteria covered microscope looking for Martian bacteria because that would kinda nullify the results.
But anyway, I care. I personally feel that we have a responsibility to do whatever we can to take life off this planet ASAP. What if earth is rendered uninhabitable by some unforeseeable cosmic event? As far as we know life is unique to this planet and it would be kinda a bummer to see it all get wiped out when there was a chance to let it restart somewhere else. I'm morally opposed to protecting other planets from ourselves.
The whole article they talk about taking care of the solar system for future research, but fuck future research; if we successfully dropped life onto another planet, that would be way more interesting than our typical: "this rock has more iron than that rock," and I really see no need to save those rocks for our great grandchildren at the expense of creating alien life.
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Given that the determination of life outside our little planet is one the fundamental questions asked of the space program, seeding bits of ourselves, or even the reasonable possibility of contamination muddies the waters. You don't want to be accused of bringing the first novel bit of off planet life with you from the get go.
Re:Office Of Planetary Protection? (Score:5, Informative)
I'm so glad we put so much effort into protecting other planets.
Now how about we stop tossing radioactive shit all over our own? kthx.
I don't think that's NASA's department. You'd have to talk to the Department of Energy to ask them to stop letting coal plants emit so much radioactive waste products if your goal is to limit radiation release.
Why not let the bacteria live? (Score:1)
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.
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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.
better to err on side of caution (Score:2)
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
Re:better to err on side of caution (Score:4, Insightful)
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.
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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.
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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.
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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
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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?
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230 to 295 degrees Fahrenheit? (Score:1)
Yeah, that'll work [earthsky.org]
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It's unlikely that those bugs would be present in a 70 degree clean room with low relative humidity :)
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So those organisms survive when the water turns to steam? I doubt it.
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So those organisms survive when the water turns to steam? I doubt it.
Stop doubting [wikipedia.org] - thermal energy was one of the first to used by bacteria.
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But at the pressures those bacteria live, water is still liquid at high temperatures.
EOP. OPE. OPP. (Score:2)
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?
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Ice cream, Mandrake... Children's ice cream!
alcohol? doesn't kill them all (Score:2)
many types of Clostridium and tetanus bacteria can take 90 percent alcohol solution for *hours*
Re:alcohol? doesn't kill them all (Score:5, Informative)
Trek (Score:1)
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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
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There are 400 billion stars in our Galaxy. Each one of us could take a crap on a different planet, and that would still leave a 1% margin of error when we detect life on another planet.
Environmentalism belongs in an environment where actual living breathing human lives are at stake.
ps - those visiting to Mars will have to hold in their farts.
But for the foreseeable future, we're not going to be visiting anything outside our solar system.
Protecting the Solar System From Contamination (Score:1)
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.
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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 got it Backwords (Score:2)
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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.
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If the only life in the universe is found right here on earth,
"If" is an interesting question. And I'd like to see science be able to take steps towards an answer. Which is why it's stupid to spread Earthly bacteria until we can at least check if the obvious places in the solar system already have their own alien life. Mars, Europa, etc. If they are truly dead, go nuts.
as Ian sez: (Score:1)
So is alcohol sufficient? (Score:2)
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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 about radiation? (Score:1)
What effect, if any, does constantly being bombarded by ionizing radiation while in space transit have on sterilization?
I for one will welcome (Score:2)
our hitchhiking overlords when they return to Mother Earth.
Does it matter where it comes from? (Score:2)
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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
no brainer (Score:1)
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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.
All I know is... (Score:2)
computer viruses? (Score:2)
How would you get them mixed up? (Score:1)
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.
Why not? (Score:2)
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.
Because. (Score:2)
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.
Andromeda Strain (Score:2)
Tested alcohol regularely? (Score:3)
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.
Tardigrades (Score:1)
I'd be more afraid of... (Score:2)
I'd be more afraid of intelligent extraterrestrial life extrapolating our location using the trajectory of our spacecraft.
Kickin' Martian Butt! (Score:2)
Ha!
That's the end of you, then, Earth-invading Martian Scum [wikipedia.org]!
Where have the scientists gone? (Score:1)
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.?
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