Slashdot Mirror
Mars Exploration Must Consider Contamination
letxa2000 writes: "CNN is reporting that the National Research Council has submitted a report to NASA that recommends certain precautions be taken if NASA is to send astronauts to Mars to guarantee that they don't bring back Mars-based bacteria and contaminate earth; including possibly banning the return vehicle from entering the Earth's atmosphere. What is the likelihood of bacterial life on Mars infecting the earth if we ever get around to visiting Mars in person?"
Putting a scare of contamination into people is just a way of hyping the possibility of life on mars and the necessity of going there.
t
Shouldn't we be more worried about the other way around first - the contamination of Mars by some Earthly micro-organism?
If life exists on Mars, it has to be about as simple a a bacteria. Under this assumption, there really isnt much risk that it would be wiped out by an Earth contaminant. Simple life forms adapt extremely quickly. Look how quickly bacterial adapt to antibiotics.
Im not here now... Im out KILLING pepperoni
A toxin might kill an astronaut. That would be tragic, but not a disaster. The problem to be worried about is communicable disease, namely an organism (bacteria, virus) that harms the host and can spread. The organisms that work this way on this planet have evolved with us over a very long period of time. An organism that had never encountered a human before, or perhaps even earthly DNA, seems exceedingly unlikely to be communicable -- hasn't had the practice.
Still, I have to admit, this sounds an awful lot like, "this code should work".
I think the answer to that has been a resounding no. IIRC, we've had meteors fall that contained earth organisms still alive on them even after re-entry. There have also been many simulated re-entries that also show bacteria can withstand huge impacts and heat well enough to contaminate the earth in the event of a meteor strike.
Actually, I'm willing to bet Earth & Mars have already cross-contaminated each other, though at what point in time, I have no idea. Both planets have been hit hard enough to throw up ejecta which could have escaped the atmosphere and made it to the sister planet. Things change, of course, so the notion that we swapped bacteria with Mars a couple billion years ago is no reason not to wipe our feet before coming inside.
--
Freeper Logic
The most ironic thing is that if a person is sent to Mars, they will almost innevitably be called a 'Hero'.
Why? Because they were able to see more than any electrical equipment? No - machines would be able to see with much greater clarity without disturbing the environment they are examining. Because they can perform actions that no machine can? No - a machine that was allowed the weight of a human being, and the environmental protection of a human being, then given the budget of a human being would be able to do thousands of times the unique experiments a human would have time to do on the first trip - and it wouldn't need to come back either.
Now admittedly, this is more of a rant - but humans do not have any special reason to take the great pains needed to go into space to explore. Machines can, and do explore much better. Once a plan is made to make an environment outside of earth livable, and a sound plan is made, then it would be beneficial to have humans live in that environment. We do NOT need a human on Mars, nor do we need to spend the overwhelming resources needed to put a human on Mars.
I know, I know - it's not science that drives this, and now mostly, the only way to get the budget is to send a senator or other large source of money where they want to go, and fit science in after the ego. But if we have to go this route, couldn't we just go ahead and put McDonalds and AOL ads on permanant banners on Mars instead of having to send a human? Maybe make little human robots, controlled in a sort of a battletech way by senators and rich people on earth instead.
I'd much rather hear the press worry about the viral influence of children looking through their new high-powered telescope looking for the Pringle's ad on Phobos than the paranoia that would come from a human being sent to mars, and all that involves.
Any other "better than sending a human" ideas?
:^)
Ryan Fenton
The fact of the matter is that preventing contamination is impossible - we have pieces of Mars rock entering our atmosphere all the time. Most bacteria is incredibly hardy - the vacuum of space and heat of re-entry are certainly survivable. Please see this essay, entitled "Estimated Flux of Rocks Bearing Viable Lifeforms Exchanged Between Earth and Mars". Realistically, our primary concern is with accidentally seeding Mars with Terran bacteria - if that happens, we may never know whether or not Mars had any native life.
sending people is more expensive but it gets you more funding as well.
Once we know one way or another what kind of life exists on mars, then we can start thinking about sending humans. But that will invariably and irrevocably change mars.
And what makes you think that there never were fleshy beings on mars, who were subsequently eaten by a flesh-eating bacterium?
The martians said the same thing...
"We don't need to worry about flesh-eating bacteria on earth; just because it killed the dinosaurs doesn't mean it'll harm us.."
Although we're aware only of life based on DNA/RNA/protein as paradigm, there may well be many other possible life paradigms elsewhere, including Mars, and most of them would be so at variance in structure that infection would be unlikely (a silicon based chemistry wouldn't likely be able to infect most conceivable carbon based lifeforms), but as an ecology another planet may successfully supplant ours: look at how oxygen-using organisms supplanted anaerobic lifeforms that had ruled the Earth for much of its existence. I don't think it hurts to be cautious.
The idea that a Martian microbe could be pathogenic to earthly life is basically dumb. NASA doesn't believe this for a second.
So what's the bottom line of this red herring? Easy. NASA is now way too much of a fat, incompetent organization to dream of sending a man to Mars. They can barely get a simple Low Earth Orbit space station going for billions over an already bloated budget. Fearmongering is one (very low) way that they can produce classic FUD (fear, uncertainty, and doubt) about the very idea to let them off of the hook for not being able to produce such a mission.
Goodness, let alone so-called Mars bacteria. Let's think about this - if Mars has bacteria on it at all, shouldn't it have evolved at roughly the same rate as Earth's?
You cannot compare. Since Martian bacteria would face different evolutionary preassures. On Mars surviving extremes to temperature is more important than on Earth. On Earth surviving in an oxygen rich environment is important, as is competition with all sorts of other organisms. (Including many which have sophisticated methods of killing bacteria.)
All right, Mr. Submitter, I'll answer your question: I haven't the foggiest idea. I've learned a little here or there about microorganisms and their possible existence outside of the Earth during my lifetime, and I regard myself as a relatively intelligent person, and tend to have strong opinions about most anything, including stuff I don't know much about. But the awful truth is that I'm not the least bit qualified to speculate on the likelihood of extraterrestrial infections on Earth. That's not an informative answer, I admit, but it's honest, and I daresay a great deal more honest than nearly all of the responses you've received so far.
To be sure, there have been a few replies so far that seem to be thoughtful and well-informed, and perhaps they come from people who really are qualified to answer the question; but like I said, I'm not really qualified to make that evaluation. Almost all of the rest, it seems to me, are comments from people who may be relatively intelligent, may have read a thing or two about the possibility of extraterrestrial life, and have all kinds of strong opinions about anything, and now they are speculating with wild abandon. Which is fun, but they will give you almost no reliable answers to your question, and may lead you completely astray.
You probably wouldn't be having this problem if you had posted this question in a forum about "News for Molecular Biologists, Stuff That Matters to Astrophysicists". Why did you expect you expect to get any useful answers here?
Always keep a sapphire in your mind
Shouldn't they also be concerned about bacteria from earth contaminating Mars? I sure hope they have been. It would be a shame if we sent someone up there only to discover that Mars was crawling with life, but that the life rode to Mars on one of the earlier probes.