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PraedSt
2008-Oct-02, 03:03 PM
Got this idea from another post.

I think finding life on Mars, or indeed any body in the Solar System, would be a complete disaster.

Some version of the Prime Directive would kick in sooner than you can say deoxyribonucleic acid.

Just think. No humans. No exploration. No mining. No colonisation. No science. The End.

Who agrees with me? And who thinks I'm a soulless capitalist pig, who should be lynched?

MaDeR
2008-Oct-02, 03:19 PM
I think that discovery of life on, for example, Mars, would cause completely opposite effect - at last reason good enough for Joe Average for pouring tens of bilions $ into Mars missions and flying there in person!

Of course, there will be always pseudoecologs, various cranks and other fringe that would consider life-bearing place unconditionally off limit. But who care about them?

PraedSt
2008-Oct-02, 03:24 PM
One can hope.

But, as I'm sure you've noticed, every passing year brings 'pseudoecologs, various cranks and other fringe' closer and closer to the centre.

djellison
2008-Oct-02, 03:35 PM
No humans. No exploration. No mining. No colonisation. No science. The End.

The discovery of life on mars would mean more science, more exploration, it would drive forward the push to put people on Mars, which in turn could lead to colonisation. In essence, it would be the beginning.

PraedSt
2008-Oct-02, 03:45 PM
The discovery of life on mars would mean more science, more exploration, it would drive forward the push to put people on Mars, which in turn could lead to colonisation. In essence, it would be the beginning.

Like I said, I hope so!

But I think certain people would kick up a fuss

Exobiologists: They wouldn't want Martian life to be contaminated
Medical profession: They'd be worried about disease
Greenpeace: They'd want to be the biggest pain possible

This is how it would start.

Ilya
2008-Oct-02, 03:48 PM
One can hope.

But, as I'm sure you've noticed, every passing year brings 'pseudoecologs, various cranks and other fringe' closer and closer to the centre.
I disagree.

In 1989, eco-cranks (to shorted your descriptive but unweildy term :) ) brought a lawsuit to stop the launch of plutonium-powered Galileo probe. The suit was dismissed, but NASA had to take it seriously. They also staged a huge protest during launch itself.

In 1997 the lawsuit to stop Cassini probe never got formally recognized, and only a few dozen eco-cranks protested. In 2006 the same group made some noises agains New Horizons, but never even filed a lawsuit, and I don't think there were any protesters.

Don't know about the rest of the world, but in US eco-cranks are on the wane.

PraedSt
2008-Oct-02, 04:10 PM
I disagree.

Ok, let's agree to disagree on this one :)

I just think that the discovery of another form of life, another biology, would be so profound, that a coalition of interests would form to prevent any exploitation of the planet in question.

Let me add to my list from above:

Religious leaders
Zoologists
Geneticists
Philosophers
Musicians (Save the Martians)

Hell, even ordinary people might well think 'let them develop to where they may, undisturbed'

Because, make no mistake, if their biology is different to ours, the chances are high that either they will eventually go extinct, or we will.

MaDeR
2008-Oct-02, 04:31 PM
I just think that the discovery of another form of life, another biology, would be so profound, that a coalition of interests would form to prevent any exploitation of the planet in question.
Yes, a coalition would form. But with complete different goals. :)


Hell, even ordinary people might well think 'let them develop to where they may, undisturbed'
Maybe, as space geek, i do not know what is really preferred in world of Joe Average, but I really think that Joe would be for exploration, science and study of extraterrestrial life. It would be one of few reasons good enough for Joe to pay tens of billions $ on space every year, effectively raising NASA budget a few times without any opposition in Congress!


if their biology is different to ours, the chances are high that either they will eventually go extinct, or we will.
No, on contrary. Their biology MUST be same or almost as ours if they have to had any chance to infect and kill us. Our bacteria, viruses and other nice, deadly particles have very sophisticated means to enter our organism and cells, and live off/change genetic machinery to produce more copies of themself. This is like key and lock - they must match. Coincidentally matching key to our cells in Martian organisms is practically impossible.

In other words, more difference = more safety. And, of course, more information about real diversity of life in our Universe.

samkent
2008-Oct-02, 04:33 PM
Hell, even ordinary people might well think 'let them develop to where they may, undisturbed'

So totally WRONG.
Remember the Mayians and Incans?
Remember th American indians?

If there is something there we want WE WILL TAKE IT!

It's what we do. It's who we are.

PraedSt
2008-Oct-02, 04:42 PM
If there is something there we want WE WILL TAKE IT!

Heh. So true.

Unfortunately, killing people for resources seems to be frowned upon these days :)


I have to say though, I'm pleasantly surprised everyone has disagreed so far. Maybe I'm being unduly pessimistic.

Swift
2008-Oct-02, 04:49 PM
Who agrees with me? And who thinks I'm a soulless capitalist pig, who should be lynched?
Isn't there a third choice? ;)

I don't agree, but I don't think you should be lynched (I like pigs and I am undecided as to the existence of souls). :D

I suspect there will be people who are against it, there is always someone who is against anything. But I suspect, as others have said, there will be an overall positive effect.

Pippin
2008-Oct-02, 06:05 PM
Heh. So true.

Unfortunately, killing people for resources seems to be frowned upon these days :)


Frowned upon yes, but still widely practiced. If said found planet, asteroid etc. had any exploitable resource humans would find a way. Of course I'm sure we would be willing to set aside 5% of Mars as a conservation area for the native fauna/flora though :silenced:

PraedSt
2008-Oct-02, 06:27 PM
We have a 'Prime Directive' of sorts for the Antarctic, don't we? 'Thou shalt not exploit the Continent for evil profits'.

Although I think we've all agreed to that because no one really wants to live in a freezer.

And we have the 'Non-Weaponisation of Space Treaty', or whatever it's called.

So the precedent is there...

Anyone on this forum know any Space Law by the way? Your input would be appreciated!

Thanks

Argos
2008-Oct-02, 06:29 PM
Given the proliferation of Evironmental Protection Areas here on Earth, where access is becoming increasingly difficult [as my experience down here shows] I wouldnīt be surprised if your worries turned out to be true.

PraedSt
2008-Oct-02, 06:34 PM
Where is this: 22°20'42"S / 49°03'14"W exactly? Brazil?

Argos
2008-Oct-02, 06:38 PM
Yes. :)

Swift
2008-Oct-02, 07:00 PM
Given the proliferation of Evironmental Protection Areas here on Earth, where access is becoming increasingly difficult [as my experience down here shows] I wouldnīt be surprised if your worries turned out to be true.
But I don't know of any environmentally protected areas on Earth where research is forbidden, at least by qualified researchers with permission.

If life is found on Mars, it might have some impact on human's plans for the planet. As others have pointed out, it might actually increase interest in exploration, whether by probes or humans. And obviously, even if only for the sake of such research, such work would have to take steps not to destroy what they were trying to study. IIRC, NASA already does that.

It also might have some long term effects on future efforts to either colonize Mars, or even terraform it. But we are a long way away from such efforts, even if we didn't care about protecting "the natives".

Comparisons to such things as the colonization of the Americas by Europeans is, IMHO, silly. First, we are not talking about a Martian civilization; I think the mostly wildly optimistic expectation of current life is microbes. Second, I think humans have become wiser and a little more "thoughtful" (for lack of a better term) in the past 200 or more years.

Certainly, calling it a "disaster" seems to be wrong.

marsbug
2008-Oct-02, 07:17 PM
I think it would depend on the life we found as well. If it were found that earth and mars life had acommon origin, or that mars life was descended from earth life I can easily see that being spun as an argument for colonisation. If life is being transferred from earth to mars naturally life making the trip on a space ship is just an extension of what happens anyway. Once fuss over the fact that life does survive there has worn off I don't think many people will loose sleep over the fate of microbes.

PraedSt
2008-Oct-02, 07:26 PM
Ah, but what about the 'we too descend from microbes, lets give them a chance' argument? :)

Couldn't happen on Mars of course, but maybe on Europa?

Swift
2008-Oct-02, 07:53 PM
I think it would depend on the life we found as well. If it were found that earth and mars life had acommon origin, or that mars life was descended from earth life I can easily see that being spun as an argument for colonisation. If life is being transferred from earth to mars naturally life making the trip on a space ship is just an extension of what happens anyway. Once fuss over the fact that life does survive there has worn off I don't think many people will loose sleep over the fate of microbes.
I understand your point, but I don't think it would make a difference. Even if true, millions or billions of years of divergent evolution in very different environments (depending on when the last transfer took place) would make Mars life so different as to be worthy of separate preservation or study.

Don't get me wrong, if we find life on Mars, I think we need to preserve and protect it. I just don't think it would be a disaster and I don't think it would end exploration. I'm unsure about colonization, but that is far enough out that we can take a "wait and see" attitude.

iquestor
2008-Oct-02, 08:32 PM
:cool:This is a really great topic. Good Job.

I do think there would be a lot of discussion about the rights of the martian biology to exist without interference. I think that the areas where life was found would be explored robotically, but human contact might become a controversy.

Swift
2008-Oct-02, 09:06 PM
I think that the areas where life was found would be explored robotically, but human contact might become a controversy.
I'll even take that a slight step further. I don't think there is an inalienable human right, either for individuals or the species, to go anywhere with no limitations. I think, for example, that should be places on Earth (that are particularly sensitive or ecologically valuable) that are protected from all human disturbance or visitation. I can see this principle extended to Mars. But I also suspect we could do that without limiting all human visitation to Mars.

PraedSt
2008-Oct-02, 09:14 PM
:cool:This is a really great topic. Good Job.

Thanks.

I forgot to credit you actually. The idea came from your post http://www.bautforum.com/space-exploration/79558-moonbase-mars-mission.html and a comment from JonClarke

This is also part of an undercover effort to get everyone converted to Orbitals: http://www.bautforum.com/questions-answers/79495-planetary-colony-orbital-habitat.html :)

PraedSt
2008-Oct-02, 09:24 PM
But I also suspect we could do that without limiting all human visitation to Mars.

Total isolation might be required. I'm not sure that's possible without avoiding landings altogether.

I like your idea of replicating those areas on Earth you mentioned, but I'm pretty sure that plenty of biological exchange takes place.

Life finds a way, as someone in a dino movie once said. :)

Argos
2008-Oct-02, 09:40 PM
I really donīt think the mere human presence 'per se' could emperil the survival of other species in anywhere. I think thatīs an over-zealous, almost religious, stance.

Warren Platts
2008-Oct-02, 09:50 PM
The Outer Space Treaty prohibits "contamination" of celestial bodies. However, if there is life on Mars, it is most likely buried deep in underground aquifers. So humans living on the surface wouldn't have much of an effect. There is a problem on Earth with natural gas reservoirs getting contaminated by H2S producing bacteria, however, that over time turn pure natural gas into "sour" gas that must be treated to remove the H2S. Thus, any drilling efforts would have to take measures to ensure that the native flora did not have to compete with terrestrial bacteria.

Vilkata
2008-Oct-03, 02:14 AM
Slighty off topic.

Perhaps if a NASA probe or human explorers did "contaminate" Mars with earth bacteria, Greenpeace and the usual suspects would sue NASA profusely.

But that brings up a question that has always confused me.

Just exactly how many microbes survive on space probes to Mars? If we could examine the Viking landers in detail, would we find thriving micro-organism colonies? Would there be any viable Earth life on the landers? If so, then there already is life on Mars. We brought it there. If there isn't, then whats with all this "contamination" talk?

---Vil.

Jens
2008-Oct-03, 05:49 AM
Yes. :)

Were you answering the question, or just making a comment about your signature file? :)

Ronald Brak
2008-Oct-03, 06:06 AM
There are plenty of examples of life being discovered on earth and not too many examples of it not being used and abused for fun and profit, so based on that, I think that if Martian mole people are discovered they will end up stitching our shoes together for us at 20 cents a Martian day.

djellison
2008-Oct-03, 09:17 AM
Like I said, I hope so!
Exobiologists: They wouldn't want Martian life to be contaminated
Medical profession: They'd be worried about disease
Greenpeace: They'd want to be the biggest pain possible
.

Exobiologists would want to collect it and study it
Medical professionals would want to see what it might teach us

And Greenpeace? This is the Red Planet - not their jurisdiction :D

PraedSt
2008-Oct-03, 09:41 AM
I think that if Martian mole people are discovered they will end up stitching our shoes together for us at 20 cents a Martian day.

Heh.

The UN Committee on Equality and Greyness for Solar Systemites issued the following press release today:

The Martian day is approximately 40mins longer than ours. On an adjusted basis, this means that Martians actually work for a soul-sapping 19.5 cents a day. This is an outrage!

The Mars rotation rate should obviously be increased. The Bill we have presented in the Assembly today, the Agreement for the Restitution of Sol Equivalence (ARSE) should go a long way towards addressing the deficiencies of the Solar System. We hope all fair minded Earthlings will support it.

Warren Platts
2008-Oct-03, 12:19 PM
I think it was Carl Sagan who said he liked Mars just the way it is.

JonClarke
2008-Oct-03, 11:47 PM
We have a 'Prime Directive' of sorts for the Antarctic, don't we? 'Thou shalt not exploit the Continent for evil profits'.

The key word there is evil. In the context of the Antarctic fishing, sealing, whaling, etc. mining and petroleum extraction are widely considered in appproaite activities and there was and is a broad international consensus for this at both a grass roots and governmental level.

Tourism is an expanding bsuiness however, and many companies do very nicely providing logistic support to Antarctic programs.

Jon

JonClarke
2008-Oct-03, 11:50 PM
Exobiologists would want to collect it and study it
Medical professionals would want to see what it might teach us

And Greenpeace? This is the Red Planet - not their jurisdiction :D

One of the few bits of KSR's Mars Triology I liked was how "Greens" were for rampant development and "Reds" were for preservation.

Me? I'm for a rainbow Mars.

Jon

Vultur
2008-Oct-03, 11:52 PM
I always kind of hoped someone could figure out a non-environmentally destructive way to set up an Antarctic colony. It seems like the katabatic winds would be good enough to power an arcology-type structure; such a city would need cooling, and Antarctica might be the only place that wouldn't be a problem.

I'd like to experience the 6-month day/night cycle someday...

OK, I think I'm in "read too much science fiction" mode.

JonClarke
2008-Oct-04, 12:30 AM
It is important to address these issues ahead of time. There is already a literature out there exploring heritiage and conservation issues on Mars, of both natural features and human relics. Baxter, McKay, Murphy, Cockell, for example. As on Earth there will be features with very high level preservation requirements and other with less so. This is just applying best practice standards to Mars.

Jon

toothdust
2008-Oct-05, 12:06 AM
I agree with you on a certain level. I think that some sort of prime directive would be instated were we to find a planet similar to Earth, in habited by countless life forms, especially if some of them were similar to a primitive form of us, ie they are on there way towards intelligence.

As for a local planet/moon with bacteria, I don't think that would stop us.

JonClarke
2008-Oct-05, 02:23 AM
I always kind of hoped someone could figure out a non-environmentally destructive way to set up an Antarctic colony. It seems like the katabatic winds would be good enough to power an arcology-type structure; such a city would need cooling, and Antarctica might be the only place that wouldn't be a problem.

I'd like to experience the 6-month day/night cycle someday...

OK, I think I'm in "read too much science fiction" mode.

Wind power is increasingly being used at Antarctic stations as a power source.

Jon

Ronald Brak
2008-Oct-05, 02:44 AM
Wind power is increasingly being used at Antarctic stations as a power source.

That's true. Although one low quality science fiction show had an Antartic base with howling winds, a dozen people and about a dozen megawatts worth of wind turbines. And they were complaining about the cold. You'd think they'd have enough power to run a space heater or two, wouldn't you?

marsbug
2008-Oct-05, 10:08 AM
I always kind of hoped someone could figure out a non-environmentally destructive way to set up an Antarctic colony. It seems like the katabatic winds would be good enough to power an arcology-type structure; such a city would need cooling, and Antarctica might be the only place that wouldn't be a problem.

I'd like to experience the 6-month day/night cycle someday...

OK, I think I'm in "read too much science fiction" mode.

Then I am to, I knew what you meant by arcology without even wondering!

PraedSt
2008-Oct-05, 12:54 PM
Hi. Hope you had (are having) a good weekend.

Thanks for all your answers. The majority of responders seem to be confident that exploration/colonisation might be slowed, or regulated, but not entirely stopped. And even though this is a very biased sample, I'm less pessimistic now!

eburacum45
2008-Oct-05, 01:49 PM
It may be the case that any Martian microbes are distantly related to Earth life. This will imply that they have been transferred fro Earth at some point, or alternately that Earth life was transferred long ago from Mars to Earth (or some other location. It may not be possible to distinguish between these scenarios.

If Mars life does turn out to be related in this way, some people might regard it as no more than an extension of the Earth biota, and may therefore have less respect for it. After all, the microbial inhabitants of Earth are generally not regarded in high esteem.

But if Mars life turns out to be entirely unrelated to Earth life, then there may be more weight to the argument for preservation. This may well slow down colonisation somewhat.

PraedSt
2008-Oct-05, 03:20 PM
As I understand it, nuclei acids (as RNA and DNA) underpin all life on Earth.

Could that be the criterion?

If the life we find is based on nucleic acids- ignore it. If it's based on a different, exotic molecule- preserve it.

Simply put, of course.

??

JonClarke
2008-Oct-06, 02:49 AM
As I understand it, nuclei acids (as RNA and DNA) underpin all life on Earth.

Could that be the criterion?

If the life we find is based on nucleic acids- ignore it. If it's based on a different, exotic molecule- preserve it.

Simply put, of course.

??

It may be that nucleic acids are the universal for encoding genetic information. Not neccessarily DNA or RNA, of course.

Either way it is better to be careful than destructive.

Jon

PraedSt
2008-Oct-06, 05:16 AM
Either way it is better to be careful than destructive

I agree.

Personally, I do think the entire body, planet or moon, should be completely isolated if any life is found on it- just to give it a fair chance.

Which is why, of course, I'd rather no life was found in the first place.

JonClarke
2008-Oct-06, 10:41 AM
I agree.

Personally, I do think the entire body, planet or moon, should be completely isolated if any life is found on it- just to give it a fair chance.

Which is why, of course, I'd rather no life was found in the first place.

The scientific significance of such a disovery would mean that ways would be found to study it.

Since life on Mars, if it exists, is neither widespread nor easy to find, we will only find it after a lot more work has been done. Maybe in deep aquifers, or in widely scattered vents or springs. But the time we have done so there will almost certainly be dozens, maybe scores of landings, perhaps even human missions.

I would think it will be very hard to declare Mars off limits by then, even without the science interest.


Jon

joema
2008-Oct-06, 11:13 PM
...I think finding life on Mars, or indeed any body in the Solar System, would be a complete disaster...Some version of the Prime Directive would kick in...No exploration...No science. The End...
The truth seems otherwise.

After Viking failed to find any signs of life, one of the Viking scientists lamented had it only photographed a palm tree, there would be an immediate highly-funded exploration program. That scenario is much more likely than discovery of extraterrestrial life resulting in "no exploration" and "no science".

Noclevername
2008-Oct-07, 01:12 PM
Hi. Hope you had (are having) a good weekend.

Thanks for all your answers. The majority of responders seem to be confident that exploration/colonisation might be slowed, or regulated, but not entirely stopped. And even though this is a very biased sample, I'm less pessimistic now!

In the long run, the anti-science Luddites can't win, simply because genies cannot be put back into bottles. If something can be done, someone will do it, and then everyone else has to either catch up or get out-competed.

Sooner or later, someone will go to Mars, just because the capacity to do so exists, and because it's there. It's human nature.

toothdust
2008-Oct-07, 03:01 PM
I think its kind of ironic, funny and somewhat sad that some of us on here are so adamant about preserving a few Martian microbes that may or may not exist, that we could probably easily study, visit and habitate their surroundings, all without harming them or wiping them out; all the while we pillage our own planet, mainly the rainforests, where countless unknown species of plants and animals reside that are just waiting to be discovered. I have read somewhere that biologists agree that only about 25% of all species of life on Earth are known to us. And here we are raping our ecosystems, lost in a debate about Martian microbes that we don't even know are there or not.

marsbug
2008-Oct-07, 03:25 PM
Good criticism but some have been screaming that for years, and it either hasn't made blind bit of difference or what action it has roused has been a sad example of too little too late.

Bear in mind the people doing the felling are just making a living and feeding thier families, and if they weren't destroying ecosystems they might be jobless homeless and starving.... not a great victory for enviromentalism. On mars, if we do find life, at least such quandries wont hang over the issue of conservation.

PraedSt
2008-Oct-08, 09:01 AM
I think its kind of ironic...

Bear in mind the people doing the felling...

Yeah, good points, but I'm in two minds about this. It's a controversial topic isn't it?

Nevertheless, if you believe in the 'we're killing the Earth' thesis, all the more reason to ship people out into space I think.

marsbug
2008-Oct-08, 10:35 AM
I would have looked at it from the other direction: If we're killing the earth all the more reason to export life to barren worlds and then let it take it's own course, to ensure diversity is not lost! I don't think there are any really easy answers to questions like these.

A world that might merit strict conservation even though it's apparently lifeless is Titan. As the whole moon is a giant organic chemistry experiment thats been running for 3 billion years plus we might learn more from studying it as is than trying to make it liveable. And there is always the slim chance that the experiment has given rise to it's own low temperature take on 'life'.

However evn if titan is decared a strictly no landings zone (unlikely IMHO) I still think there'll be a flotilla of space craft studying it from above, and that can only be a boost for space exploration

Ilya
2008-Oct-08, 01:01 PM
How about this -- If we're killing the earth all the more reason to move polluting industry and energy production into orbit! Much more practical than trying to make Titan livable.

springa
2008-Oct-08, 01:48 PM
In the short term, I think that the discovery of microbial life on Mars would probably greatly increase scientific and popular interest in the planet and lead to more extensive exploration by unmanned spacecraft and manned missions. In the longer term, it might restrict human settlement/exploitation of Mars if these activities would be dangerous to survival of much of Martian life. Terraforming, in particular, would be very problematic because it might make most of the planet uninhabitable to its own native life forms.

I'm pretty sure that it would NOT lead to a "quarantine" of the planet. Given how curious a lot of scientists and ordinary people are about extraterrestrial life (even if it is microscopic), there's no way that everyone would agree to stop studying Martian life forms as soon as they are discovered.

Warren Platts
2008-Oct-08, 06:41 PM
Since life on Mars, if it exists, is neither widespread nor easy to find, we will only find it after a lot more work has been done. Maybe in deep aquifers, or in widely scattered vents or springs. But the time we have done so there will almost certainly be dozens, maybe scores of landings, perhaps even human missions.

I would think it will be very hard to declare Mars off limits by then, even without the science interest.


Jon
Arguably, the original Viking mission did detect life. At any rate, one cannot say that Viking conclusively did not detect life. And since the Viking missions, not one mission has included equipment designed to directly detect life! Talk about conspiracy fodder! It's like they're afraid of detecting life.

PraedSt
2008-Oct-08, 06:56 PM
not one mission has included equipment designed to directly detect life!

At the risk of having this shunted over to CT, I'd have to say I've wondered about this too.
Do the biologists have a simple, universal test for life?
If so, why hasn't it been employed? If not, why hasn't it been paid for, developed?
(Life as we know it, of course)

marsbug
2008-Oct-08, 08:43 PM
We don't have a universal test for life because we don't have a universal definition for life. A thread that touches on this subject (http://www.bautforum.com/general-science/78078-life-non-life-what-lies-between-how-do-we-define.html), and I'm sure there are lots of others. That one wanders a lot, mostly because I started it in a very unclear fashion...

JonClarke
2008-Oct-08, 09:36 PM
Arguably, the original Viking mission did detect life. At any rate, one cannot say that Viking conclusively did not detect life. And since the Viking missions, not one mission has included equipment designed to directly detect life! Talk about conspiracy fodder! It's like they're afraid of detecting life.

And here we have a methodological problem. How does none "directly detect life"? Especially when tthe presence and nature of that life are both unknown? Their metabolism? Their morphology? Their movement? Their bodies? Their isotopic signatures? It is not easy.

The three Viking astrobiology experiments were designed to detect the results of metabolism, based on a range of very general assumptions about what alien metabolism might mean - nutrient uptake, gas release, and gas exchange. All three gave ambiguous results. A fourth experiment, the gas chromatograph and mass spectrometer measured the abundance of organic matter and isotope signatures, in other words the phsycial consistuents of (carbon) life, and the chemical signatures of its present. These were conclusively negative.

Unless we find evidence for their bodies, tests for martian metabolism are pointless. So Beagle 2, Mars 96.MPL and Phoenix all carried a MS. Beagle 2 also carried a GC. MPL and Phoenix carried TEGA which could detect organics by pyrolysis. So far the Pheonix MS and TGA results have been negative for organics and for isotopic anomalies, although it is early days.

As for other methods, the MERs, Beagle 2, Mars 96 and Phoenix all carried optical microscopes, Phoenix has an AFM as well. None of these have shown anything convincingly biological or evidence for biological movement.

So while nobody has repeated the Viking metabolic experiments (with good reason, why repeat experiments that gave inconclusive results?) many other experiments have been flown that can directly and indirectly look for life. Unfortunately most of the best did not make it.

Jon

PraedSt
2008-Oct-09, 09:46 AM
We don't have a universal test for life because we don't have a universal definition for life. A thread that touches on this subject, and I'm sure there are lots of others. That one wanders a lot, mostly because I started it in a very unclear fashion...
Thanks marsburg. The thread's fine!
And I know we don't have a universal definition of life, so my original question was a bad one!
At the risk of another stupid question, how about a simple culture test, like we do here? You might need a microscope, but if you're lucky a simple camera would do. If nothing else, you could at least say 'there's no Earth-like bacteria in this sample'.
Mmmm...I'm hoping that that statement advances the line of inquiry. Might be a totally useless statement.

Anyway, this would cover morphology and bodies from the first para of JonClarke's post. So same question to you JonClarke!

Also, at the end of your post:

Unfortunately most of the best did not make it

Weight issues?

Thanks

marsbug
2008-Oct-09, 12:46 PM
If we find a fairly earth like environment to test then a culture test would be one approach to use, but even different earth bacteria wont always grow on each others habitats. Some cold loving bugs wont grow at room temperature, some extreme heat lovers won't grow below 80 deg c etc.

These days i'm more and more of the opinion that, although there may still be a little life hiding somwhere on mars, the outer planets moons are the better place to look. In fact right now I'd rate titan as the most interesting place. The complex organic chemistry in the atmosphere is certainly relavant to lifes origin, and interesting in its own right, it may well have a subsurface ocean, has liquid seas (of methane but how do we know that couldn't work?)on its surface, and has probably seen surface pools of water during impacts and eruptions in the past... Hence why i brought up Titan as a much better place to conserve than mars earlier.

I think the way forward might be to forget about looking for 'life', and just look for interesting phenomena with their own unique properties. If we find a world has something interesting we want to study we think about conserving it. If it's a boring desert we can do what we want with it.

Of course different people are interested in different things....so we need to think, and look hard, before we start making big changes to a place.

Edit: That doesn't mean I think we shouldn't change things if there's genuinly nothing of interest there, or if we can make changes without disrupting what we want to study.

Warren Platts
2008-Oct-09, 04:56 PM
And here we have a methodological problem. How does none "directly detect life"? Especially when tthe presence and nature of that life are both unknown? Their metabolism? Their morphology? Their movement? Their bodies? Their isotopic signatures? It is not easy.I will go out on a limb and say that Martian life will probably consist of tiny bacteria. What about the Martian meteorite they thought had life on it? I don't believe that myself, but whatever those things were, they were detected by an electron microscope, were they not? Seeing regular bacteria here on Earth with ordinary microscopes is not a trivial task. So it's not surprising that none of the microscopes sent so far haven't found swarms of bacteria.


Unless we find evidence for their bodies, tests for martian metabolism are pointless.There "bodies" could be tiny nanobacteria that would be difficult to see. More likely, they would exist as tiny dried spores and would be concentrated at the ppb level. Or they might be endolithic organisms. I don't believe we've sent a robot that can do thin sections of rocks yet. It would be much easier to try and culture Martian life than to try and find them with microscopes designed to look at minerals.


So Beagle 2, Mars 96.MPL and Phoenix all carried a MS. Beagle 2 also carried a GC. MPL and Phoenix carried TEGA which could detect organics by pyrolysis. So far the Pheonix MS and TGA results have been negative for organics and for isotopic anomalies, although it is early days.The results were negative, but what was the level of resolution? Can they say for sure that there was not one bacterial spore in their samples?


As for other methods, the MERs, Beagle 2, Mars 96 and Phoenix all carried optical microscopes, Phoenix has an AFM as well. None of these have shown anything convincingly biological or evidence for biological movement.Movement?


So while nobody has repeated the Viking metabolic experiments (with good reason, why repeat experiments that gave inconclusive results?) I wrote a paper on the Viking results during my undergraduate days, and IIRC, the Viking experiments were repeated on Antarctic soils known to contain life, and the same results were obtained.

You have to try and imagine what the life cycle would be like for Martian bacteria to make a living on the surface. Most of their time would be spent existing as tiny weather resistant spores. They wouldn't do anything, and wouldn't look like much. Then during very brief interludes when the temperature gets above freezing, they would grow a little bit, and then produce more spores. So the polar region where Phoenix is is probably not the best place because it never gets above freezing there. I would suggest that the best place to find surface life would be at the very lowest elevations on the planet at tropical latitudes. That would be Hellas Basin. I think one of the Viking probes was sent there if I'm not wrong.

PraedSt
2008-Oct-10, 09:04 AM
Some info about Desulforudis audaxviator, a bacterium which lives in groundwater, ~2km below the surface. Found in 2006.

Some of the wiki splurge:

This type of bacterium, approximately four micrometers in length, has survived for millions of years on chemical food sources that derive from the radioactive decay of minerals in the surrounding rock, making it one of the few creatures known that does not depend on sunlight for nourishment and the only species known to be alone in its ecosystem (Highlights added)

They've just analysed the DNA from samples, and sequenced the entire genome. The physorg.com link:
http://www.physorg.com/news142777731.html

There's good news and bad news.
The bad news, as I've highlighted above, is that they only found one species.

"We knew from previous work in these mines, using molecular biology techniques, that there seemed to be very simple communities living down there," says Fred Brockman of the Biology Department of PNNL in Washington state, where the DNA was extracted from the filtered cells. "We expected we'd have a good chance of assembling one entire genome of the most dominant species, or perhaps 70 to 80 percent of several species."

Says Chivian, "What we instead discovered was that there was only one organism present in the sample. More than 99.9 percent of the DNA came from that single organism, and the tiny remainder appeared to be trace contamination from the mine and the laboratory"


The good news is the corollary, in that it seems possible to thrive on your own.

the genome contained everything needed for the organism to sustain an independent existence and reproduce, including the ability to incorporate the elements necessary for life from inorganic sources, move freely, and protect itself from viruses, harsh conditions, and nutrient-poor periods by becoming a spore.

"One question that has arisen when considering the capacity of other planets to support life is whether organisms can exist independently, without access even to the sun," says Chivian. "The answer is yes, and here's the proof. It's sort of philosophically exciting to know that everything necessary for life can be packed into a single genome."

JonClarke
2008-Oct-11, 02:59 AM
Warren, some thoughts:


I will go out on a limb and say that Martian life will probably consist of tiny bacteria. What about the Martian meteorite they thought had life on it? I don't believe that myself, but whatever those things were, they were detected by an electron microscope, were they not? Seeing regular bacteria here on Earth with ordinary microscopes is not a trivial task. So it's not surprising that none of the microscopes sent so far haven't found swarms of bacteria.

There "bodies" could be tiny nanobacteria that would be difficult to see.

The existance of nanobacteria are highly controversial in their own right. And of course "bacteria" (nano or oterwise) are a terrestrial concept. We don't know whether martian organisms, if they exist, correspond to them.


More likely, they would exist as tiny dried spores and would be concentrated at the ppb level.

Quite possibly. This is why the Viking experiments tried various simulants to try and encourage their growth. of course since we don't know what conditions stimulate that growth. if they were present at the ppb level the Viking and Phoenix mass specs should have found them. Since they didn't that means they are at the ppt level, if there at all.


Or they might be endolithic organisms. I don't believe we've sent a robot that can do thin sections of rocks yet.

You could crush the rocks and try cultures on that. Viking could, I think, crush rock samples. Unfortunately there weren't any rocks in reach. MSL will be able to crush rocks,but can't culture.

Being able to make thin sections would be a tremendous innovation. But it is well beyond pesent robotic technology. It is a very complex task, more of a craft than anything. Especially the final stages. I don't think we will be able to this for a long time. Even when we send people there it might require too much equipment(100 kg of rock cutting and polishing equipment, plus a lot of water and grinding powders.


It would be much easier to try and culture Martian life than to try and find them with microscopes designed to look at minerals.

Well, we tried that, and it didn't work very well. And of course to culture you need to find a growth medium. That is why there were the different Viking astrobiology experiments, each with different assumptions about growth conditions. Further, even on Earth there are many microorganisms that are difficult, if not impossible to culture.

These are some of the reasons why the technology as moved away from the 60's focus on culturing towards direct identification of biomarkers and bioindicators. But of course to do that you need the organic deposits to analyse. These we haven't found.


The results were negative, but what was the level of resolution? Can they say for sure that there was not one bacterial spore in their samples?

As I recall Viking was ppm for methane and similar simple organics and ppb level for complex organics. Phoenix I understand is better than this by an order of magnitude (I have been trying to find a reference for this, without success.

Of course, you could be right, and there may be spores etc. below detection limits. Absence of evidence is not evidence of absence, and all that. But it is not evidence of presence either. As detection limits improve sooner or later you reach the point when you have to say they are just not there. Whether that is at the ppb or ppt level is something to discuss.


Movement?

Movement by a feature that could not be attributed to wind or gravity, etc., would be bioindicator. Some Viking images were taken with the specific aim of searching for movement.


I wrote a paper on the Viking results during my undergraduate days, and IIRC, the Viking experiments were repeated on Antarctic soils known to contain life, and the same results were obtained. [QUOTE]

Yeah, I remember reading about this too. Do you have the source?

Atacama surface soils from near Yunguay also show Viking-like behaviour and are sterile.

[QUOTE]You have to try and imagine what the life cycle would be like for Martian bacteria to make a living on the surface. Most of their time would be spent existing as tiny weather resistant spores. They wouldn't do anything, and wouldn't look like much. Then during very brief interludes when the temperature gets above freezing, they would grow a little bit, and then produce more spores. So the polar region where Phoenix is is probably not the best place because it never gets above freezing there. I would suggest that the best place to find surface life would be at the very lowest elevations on the planet at tropical latitudes. That would be Hellas Basin. I think one of the Viking probes was sent there if I'm not wrong.

I think Chris McKay, Carol Stoker and the others working on the Phoenix astrobiology would be gob-smacked to find live organisms. But remember a million years ago when the axial tilt was near 50 degrees the temperature would have been much warmer, warm enough for liquid water to be present. Bugs could have thrived then - if they were there. Their remains, perhaps even spores, could still be about. In which case they should show up in the mass spec and in the oven.

Viking 1 landed in the Chryse basin, which is relatively low and relatively equitorial (22N). Viking 2 landed at Utopia (48N).A mission to Hellas would be a great site for many reasons, but I don't think the significance of Hellas was fully appreciated at the time the Vikings landed. Hellas has been ruled out for subsequent missions because of engineering issues.

cheers

Jon

borman
2008-Oct-11, 05:17 PM
Martian Methane seems more likely to come from conduits from the subsurface

This does not say whether it is biotic or abiotic such as Atreya’s suggested method of formation. While it is often associated with water vapor, this correlation is not exclusive. But the features of the geography where the emissions seem to occur suggest underground collapse or faulting creating a conduit to the surface.

This was from Muma’s talk this morning at DPS40 that was live streamed over the internet. Much thanks to Mr. Bell for his successful implementation of live streaming and archiving.

You may still be able to hear the talk by clicking on the link. Muma’s talk is about 2/3 the way through. Also of considerable interest related to Muma’s talk is the localized water vapor releases and the last talk on how a combination of solar wind and crustal magnetic fields may serve to pinch off plasma and give another important route for the loss of the Martian atmosphere. The magnetic ropes pinch off and send blobs of atmosphere off into space. If these “pie in the face” blobs have intersected the Martian moons, they may be the needed repository of information of past Martian Atmospheric history that can tell evidence if Mars had a thick enough atmosphere so that is was wetter and warmer in the past. Also in the earlier Mars talk, erosion rates would be two orders greater than today’s rates if the pressure was greater.

Mars Atmosphere (Session 6)
http://cornellmediasite.cit.cornell.edu/mediasite/Viewer/Viewers/Viewer320TL.aspx?mode=Default&peid=73d7f3be-19dd-456b-a327-bf231e1d9cfd&pid=5344881c-9c50-49d4-823d-226f9cca4300&playerType=WM7