Author Topic: Value of Biologically Pristine Mars for Science and Humanity  (Read 15731 times)

Offline robertinventor

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Perhaps you may be interested to discuss this? My aim was to try to explain why it is that some scientists care so much about a biologically pristine Mars. I have found in debates here and elsewhere, and also most of the news stories about Mars colonization that there is little appreciation of this. Even amongst space scientists, it is rarely emphasized. I hope this will help promote mutual understanding between those who care for the current biologically pristine Mars and those who are keen to land humans on the surface.

Value of Biologically Pristine Mars for Science and Humanity

I posted this before but just as one link amongst several, also  have done a lot of work since then and added several new sections. Hope you enjoy it and find it a good read and interested in any comments.

Offline gospacex

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Looks like few appreciate the extraordinary value and uniqueness of a colonized Mars.

Throwing away political correctness, I'd classify people who want to ban Mars colonization as eco-nazis.

Offline robertinventor

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Looks like few appreciate the extraordinary value and uniqueness of a colonized Mars.

Throwing away political correctness, I'd classify people who want to ban Mars colonization as eco-nazis.

In what way is a colonized Mars of extraordinary value and unique? Let's have a proper debate, not just name calling. Also what is the huge urgency to colonize Mars right away before we have a chance to study it?

I'm not against colonizing Mars for ever. In the article I just said that the time for the great debate about that is not yet as we don't yet know enough, and suggested a time line of perhaps 50 years before we can do it, could be sooner if a really extensive exploration of Mars by telepresence is carried out right away.

I would then probably still argue against colonizing Mars as my own POV but it would at least be a debate based on knowledge about Mars's biological past and present, which we don't have yet.

Also, though I am against colonizing Mars surface for now, I am keen on sending humans to orbit Mars and eventually orbital colonies around Mars.

Also those humans would explore the surface via telepresence, including driving rovers on the surface at similar speeds to those you can achieve on the Earth, make fuel on Mars, eventually factories and export things to orbit. All the things you see in the Mars colonization of surface, except that the humans remain in orbit.

You can also operate telepresence humanoid bots on the surface, like the robonaut but more developed with legs as well, haptic feedback etc so e eventually I see being able to run, walk etc on the surface in a natural way just as if you were there, using avatars on the surface.
« Last Edit: 05/15/2013 09:19 AM by robertinventor »

Offline QuantumG

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In what way is a colonized Mars of extraordinary value and unique? Let's have a proper debate, not just name calling. Also what is the huge urgency to colonize Mars right away before we have a chance to study it?

I think the burden of proof is on those calling for restraint, or is it restriction?
I hear those things are awfully loud. It glides as softly as a cloud. What's it called? Monowhale!

Offline gospacex

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Looks like few appreciate the extraordinary value and uniqueness of a colonized Mars.

Throwing away political correctness, I'd classify people who want to ban Mars colonization as eco-nazis.

In what way is a colonized Mars of extraordinary value and unique?

Mars surface area is about the same as Earth land mass.

Total Earth's economic value is quite hard to quantify, but by all estimates it is well above 1000 trillion, and likely is 5 times that.

Mars populated to the about same density as Earth would be worth about the same (within an order of magnitude)

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Also what is the huge urgency to colonize Mars right away before we have a chance to study it?

What is the problem with studying Mars while it is being colonized?

Contamination argument doesn't hold water: Genesis probe crashed on landing, contaminating all samples; yet, scientists aren't as dumb as some might think. They managed to sort out contamination from the samples. I don't see why a bit of ingenuity wouldn't help scientists to unravel Mars mysteries even if some "evil Earth bacteria" contaminate Mars soil.

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I'm not against colonizing Mars for ever. In the article I just said that the time for the great debate about that is not yet as we don't yet know enough, and suggested a time line of perhaps 50 years before we can do it, could be sooner if a really extensive exploration of Mars by telepresence is carried out right away.

Okay. You are entitled to your opinion.
But there is a problem.
What shall be done if someone would try to fly and land on Mars, disregarding your opinion? Should this evil person be arrested and thrown to jail? What if he is not a US citizen? What if his rocket departs from e.g. Russia?

Offline spectre9

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Red Mars!!!!

Blow up the terraforming plants!!  :)

People will do plenty of science if/when they actually get there.

How about the value of a pristine Earth? It's only an ideal. People are a polluting and consuming virus, perhaps people will embrace this simple fact of human existence some day when they leave this garden planet.

Bringing Mars back to life will be vastly more valuable to Mars and humanity. It doesn't want to be a cold, dead world forever. Some day we will have the power to revive it and make it a home for plants and animals. Why seal it's fate as a red desert? To me that's a bit strange.

The human race doesn't even value rainforests here that highly. What's a little bit of red dirt?

Offline SiriusGrey

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Thank you, Robert, for the great summary on your site; i am sure if more people would take the time to actually read and understand the reasoning they would be less inclined to resort to name-calling.

My TL;DR version: If we put too many earth microbes on Mars - and a manned landing would certainly do that - there is consensus that there is a good chance that they will eat up any evidence of past life on mars. And the importance of any insight about past or present life on Mars can hardly be overstated.

Even shorter: There is nothing "eco" about this. This is about science and the destruction of evidence.

Luckily, NASA as an institution agrees, see http://planetaryprotection.nasa.gov

With regards to private efforts in space i expect to see regulations from the individual governments once this becomes relevant, in the U.S. this is explored e.g. in this thesis from MIT: http://dspace.mit.edu/handle/1721.1/62036.

Offline robertinventor

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Thank you, Robert, for the great summary on your site; i am sure if more people would take the time to actually read and understand the reasoning they would be less inclined to resort to name-calling.

My TL;DR version: If we put too many earth microbes on Mars - and a manned landing would certainly do that - there is consensus that there is a good chance that they will eat up any evidence of past life on mars. And the importance of any insight about past or present life on Mars can hardly be overstated.

Even shorter: There is nothing "eco" about this. This is about science and the destruction of evidence.

Luckily, NASA as an institution agrees, see http://planetaryprotection.nasa.gov

With regards to private efforts in space i expect to see regulations from the individual governments once this becomes relevant, in the U.S. this is explored e.g. in this thesis from MIT: http://dspace.mit.edu/handle/1721.1/62036.

Yes, exactly, that is just what I'm saying, thanks.

And you all might like to know, historically I started up as keen on colonization of the Mars surface as anyone else. I changed my views when I realised what the implications were for the scientific study of the origins of life on Mars.

Offline robertinventor

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Mars surface area is about the same as Earth land mass.

Total Earth's economic value is quite hard to quantify, but by all estimates it is well above 1000 trillion, and likely is 5 times that.

Mars populated to the about same density as Earth would be worth about the same (within an order of magnitude)

Okay I can see that. Could have Mars to that density if the entire surface was covered in domes (paraterraformed) - I am doubtful it can ever be terraformed to be as close to Earth as that even in centuries, but paraterraformed, yes in principle.

And yes a populated Mars does have a value, as you say, I agree. So you potentially have a conflict between the value for humans and the value for scientists, yes.

What I say in the article though is that in space you can create living areas for a hundred or a thousand times the population of Earth. In Ceres alone there is enough material for habitats with total living area at least hundreds of times that of Earth.

With the Interplanetary Transport Network gravitational trajectories linking the whole solar system you can eventually get materials from almost anywhere in the solar system to almost anywhere else, apart from deep within planetary wells and on the planetary surface, for almost no use of fuel.

So you could build those colonies of trillions of people wherever you like. And they are not vulnerable to any single planetary catastrophe like impact from big comet or whatever.

And you can also house more people in space colonies more quickly, I would argue. First of all in the early stages, because you can supply from Earth all the high tech equipment they need, and the colonists themselves, for a far lower cost, so can get a larger colony started more quickly. Then later on, because it is so easy and efficient to move material (including manufactured goods) about in space as long as time is not of the essence. From almost anywhere to almost anywhere else outside the gravitational well.

And also there is no urgency about it right now. In the future it may be possible to evacuate people from Earth. When spaceflight is as easy as plane flight, then it would be possible, total flights per year something over a billion I believe. That means the population of Earth could emigrate to space far faster than it grows, if it was possible to have efficient air breathing, say, space planes just like aeroplanes.

So, that again could be an interesting future. Hard to say how far in the future that might be but doesn't seem impossible. But there is enough time before that happens to explore Mars scientifically and find out what is there, and get started on proper space colonies, and so we know what the situation is in space. By then Mars may become like Antarctica. With all the busy traffic on Earth and all our billions of people, Antarctica remains sparely populated and free from major contamination. Partly it helps of course that it is hard to get to, and though it has minerals of commercial value, they are easier to extract from other places in the world. But the same applies to Mars relative other places in space.

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> Also what is the huge urgency to colonize Mars right away before we have a chance to study it?[

What is the problem with studying Mars while it is being colonized?

Contamination argument doesn't hold water: Genesis probe crashed on landing, contaminating all samples; yet, scientists aren't as dumb as some might think. They managed to sort out contamination from the samples. I don't see why a bit of ingenuity wouldn't help scientists to unravel Mars mysteries even if some "evil Earth bacteria" contaminate Mars soil.

But it does. Why do you think they are so careful to prevent contamination of Mars with the unmanned rovers? Why do you think the Outer Space Treaty has a specific clause preventing this, and the COSPAR guidelines classify Mars as Category IV?

Yes, with a small sample and a lot of work, in a situation where a lot of scientists working on a small amount of material is cost effective because it is so expensive to get more of it, and where you are not looking for life itself, just for a way of separating out individual dust grains that are of cometary origin from those of desert origin, then you can do it.
http://en.wikipedia.org/wiki/Genesis_(spacecraft)#Sample_extraction_and_results

The problem with doing something like this with life is that

* Life replicates and evolves, so you don't know for sure that your "dust grain contamination" on Mars still looks the same as it did on Earth. That's especially so when you have a whole planet with many different microniches for it to evolve into, get adaptive radiation like Darwin's finches but on faster timescale because of the microbial faster generation time.

* Life on Earth is nowhere near fully characterized. We don't have an inventory even of all the species that live in spacecraft assembly clean rooms. The uncultivable archaea especially are so poorely characterized we only have a few gene fragments to go on. With those we don't even know how many genera there are.

Here is a report on the micro-organisms found in spacecraft assembly clean rooms.
http://aem.asm.org/content/71/8/4163.full

* Life on Mars can go extinct, either eaten or outcompeted

* Organic samples of early life can be eaten and decomposed, making it like trying to find out what it was you ate from your faeces.

====================

MORE ABOUT THE ARTICLE ON THE CLEAN ROOM MICRO-ORGANISMS

I know it is from six years ago, but it is a nice study.

Some highlights: typically less than 1% of micro-organisms have been grown in pure culture, and that is almost certainly the case in spacecraft assembly clean rooms. The micro-organisms in the clean rooms are likely to be especially hard to culture as they are adapted to an envionment where only a sparse population is possible. DNA analysis can help you to characterize what is there, without knowing anything about the micro-organism - what it does, looks like, or how it survives. These micro-organisms are also ones likely to be able to contaminate planets because they are extremophiles already, adapted to such harsh environments/

...

Then some actual quotes
"It will be difficult to exclude Earth-derived contamination as a source of observed microbes if we do not thoroughly understand the complete composition of communities that spacecraft might inadvertently deliver.
...

 Although it is becoming possible to overcome or minimize some of these known limitations of molecular biology-based metagenomic techniques (35), we must recognize that there likely will be unknown members of many microbial communities that will resist detection by the characterization methods developed to date.
...

In summary, as discussed by scientists such as Rummel (56), Mancinelli (39), and Horneck et al. (30), planetary protection issues of great importance include minimization of the inevitable deposition of Earth microbes by humans on the surface of Mars or other potentially life-bearing locations in our solar system (59) and prevention of Martian subsurface contamination by Earth microbes and organic material. The natural environments of places in our solar system that may harbor life or complex forms of organic chemicals should be protected so that they retain their value for scientific purposes as humans design planetary missions to search for organic material (60) on and beneath the surface of other planets or to study the chemistry and mineralogy (61) of extraterrestrial landing sites.
"

Also though that paper is from 2006 a more recent paper confirms that exactly the same situation still applies today. This is a 2012 paper

http://online.liebertpub.com/doi/pdf/10.1089/ast.2011.0735
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Okay. You are entitled to your opinion.
Thanks, I appreciate it :)
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But there is a problem.
What shall be done if someone would try to fly and land on Mars, disregarding your opinion? Should this evil person be arrested and thrown to jail? What if he is not a US citizen? What if his rocket departs from e.g. Russia?

Luckily at this stage all the space faring nations are members of the Outer Space Treaty. Also spaceflight is still at the stage where you can't just take off for Mars from your back garden or local aerodrome and just fly into space.

You will need permission to launch and the host country would be required to refuse permission by international law, and surely would. Russia is a signatory of the treaty. So is China, Japan etc.

Here is the list of signatories of the Outer Space Treaty:
http://www.fas.org/nuke/control/ost/text/space5.htm

I am hopeful that longer term it will be generally understood why Mars is kept pristine. Especially once a few expeditions have been launched to study it via telepresence, and with all the interest they would generate - and with video streaming of people exploring Mars via telepresence, and scientists explaining over and over, as they do, why it is being done this way.

Everyone would just understand as they do now with Antarctica. It's not really the fault of the private companies who want to go to Mars as this whole area of concern is not widely reported in the media, and it is rare that you get news stories about it (though I have turned up one or two).

There was this reasonably well informed article in Fox News last autumn

http://www.foxnews.com/science/2012/10/25/manned-mars-missions-could-threaten-red-planet-life-2094749311/

When there are actual telepresence colonies around Mars, and when the papers are full of news stories like this about the effect Earth life would have on Mars, I think the climate of public opinion will gradually change. Takes a few years, there can be a bit of a lag, and we could do with a present day Carl Sagan to take it up and champion it, someone with charisma, integrity, and widely respected for his science, that could help speed things up.

When that is generally accepted, which I think myself will happen eventually, the private companies that want to land humans on Mars will change their ideas and look for other objectives. Unless and until of course Mars turns out to not need protection and the international law is changed.

But, can't see that happening soon, longer term is hard to say. For a scientist as I said in the article, the most interesting outcome is if Mars turns out to be so utterly fascinating biologically that you wouldn't think to contaminate it. So I am hoping for that because it is much more interesting to science, and I think there is a good chance especially when you realize how interesting it will be if life never evolved there.

Mars surface colonization enthusiasts had better hope it turns out that Mars present and past is as uninteresting biologically as the Moon.

You can do what you like on the Moon, pretty much, the chance of contamination either forward to the Moon (at least replicating on the Moon), or backwards to Earth, is now understood to be so close to zero as to be insignificant, though there may be prebiotic processes in the ice at the poles, and if life turns out to exist even in comets for instance, it could exist on the Moon. But I think few scientists expect that.

There may be contamination issues even for the Moon actually, especially a big space colony, life contamination, also exhausts from the rockets landing and taking off, especially if close to scientifically interesting and sensitive areas.

http://www.lpi.usra.edu/meetings/LEA/presentations/tues_pm/Dworkin.pdf

These links are about the water ice on the Moon btw, though should probably start a new thread if anyone wants to discuss them in detail.

http://www.sciencedaily.com/releases/2012/03/120319135245.htm

http://www.dailymail.co.uk/sciencetech/article-2162505/More-water-moon-NASA-finds-mile-deep-crater-ice-scattered-quarter-surface.html

The same thing MIGHT happen on Mars, and we MIGHT also learn so much about life from the study of exoplanets and other locations in our solar system, and extensive experiments, to gain some confidence about what would happen if you introduce Earth life to Mars and decide it doesn't matter, and won't impact on long term terrafroming.

I can't see the future anymore than anyone else, all that MIGHT happen. But I would find the future with the biologically interesting Mars much more interesting, and on present evidence it seems the more probable too.

Is that understandable? You don't have to agree with me, just, does what I say make sense?
« Last Edit: 05/15/2013 06:07 PM by robertinventor »

Offline veblen

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My TL;DR version: If we put too many earth microbes on Mars - and a manned landing would certainly do that - there is consensus that there is a good chance that they will eat up any evidence of past life on mars. And the importance of any insight about past or present life on Mars can hardly be overstated.

There is no "consensus" such as you describe, stop making stuff up.
« Last Edit: 05/15/2013 05:02 PM by veblen »

Offline robertinventor

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My TL;DR version: If we put too many earth microbes on Mars - and a manned landing would certainly do that - there is consensus that there is a good chance that they will eat up any evidence of past life on mars. And the importance of any insight about past or present life on Mars can hardly be overstated.

There is no "consensus" such as you describe, stop making stuff up.

True it used to be thought that a mission by humans to the Mars surface could be done in a biologically reversible way, just a few years back. That was when Mars was thought to be so inhospitable to life that no Earth life could possibly grow there today. Just survive as dormant states or endospores and over periods of time, even if sheltered from the sun, eventually get degraded by cosmic rays. Also it used to be thought that any micro-organisms exposed to direct sunlight would degrade rapidly so you could sterilize the soil simply with a brief exposure to the sun. The oxidizing environment of the soil also was thought to be enough to sterilize just about anything too. Perhaps 10 years or so ago that was more or less the consensus.

Some still think it is possible, so not a 100% consensus the other way at least amongst space scientists generally. But a stream of research over just the last two or three years has changed the consensus.

* First many papers that describe possible niches for life on Mars that no-one had thought of so far.

* Also many papers on extremophiles and capabilities of various even ordinary seeming micro-organisms with hidden extremophile capabilities and polyextremophiles capable of living in those habitats

* Also many papers on microorganisms capable of surviving the hostile Mars surface conditions, remaining still viable after months of exposure to surface conditions, including full sunlight, something that used to be thought impossible.

By now from the evidence of published papers, amongst those biologists who directly study the subject of contamination of Mars and publish research on it, I'd say the consensus is pretty much 100% (as for instance in those two papers on the clean rooms). It's not like you have to search hard to find published research with conclusions like this, it is what they all say pretty much. I haven't yet come across a single recent paper in these fields of research with the opposite conclusion.

But takes a while for other scientists to "catch up" and amongst the general public the scientific view is probably similar to that of ten years ago. And that all goes to show how little we know about Mars, and extremophiles, that opinions can change in this way as a result of new published research.
« Last Edit: 05/15/2013 05:41 PM by robertinventor »

Offline Warren Platts

In what way is a colonized Mars of extraordinary value and unique? Let's have a proper debate, not just name calling. Also what is the huge urgency to colonize Mars right away before we have a chance to study it?

I think the burden of proof is on those calling for restraint, or is it restriction?

The Precautionary Principle says just the opposite.

Twisting ethics to suit personal desires isn't a very convincing argument...
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline Warren Platts

Bringing Mars back to life will be vastly more valuable to Mars ... It doesn't want to be a cold, dead world forever.

Pretty radical statement: most would say Mars--being an inanimate object--doesn't "want" anything. A little more unpacking would be nice....


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The human race doesn't even value rainforests here that highly. What's a little bit of red dirt?

Some people like deserts just the way they are!
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline Warren Platts

My take (YMMV):

In the unlikely event there are macroorganisms on Mars, e.g., those lichens some people say (99% sure they are not real myself, nevertheless...) then the planet should be quarantined. Only scientists should be allowed to visit at least until we know for sure that human colonies would not cause their extinction. These would be truly unique specimens, and should be allowed to evolve unmolested.

The more likely scenario is that there is life, but it is microbial life confined to briny aquifers below the surface. If these organisms are able to exist in Mars's perchlorate-infested, poisonous ecosystem, then they are going to be very hardy creatures and unlikely to be displaced by microbes brought in accidently from Earth. After all, it's likely that there has been occasional transfers of life between the two planets in the past.

Yes, this option is risky, I admit, but if there are microorganisms on Mars, it's likely that they are practically everywhere in the solar system where there is liquid water; therefore, in the unlikely event that Martian life were to be caused to go extinct, other forms of extraterrestrial life would persist elsewhere.

And yes, I fully admit that causing extinctions of any kind is an intrinsic moral wrong, and therefore should not be undertaken lightly. However, in the case of Mars--arguably the most hospitable celestial body for humans outside of Earth--the value of extending human culture into space outweighs the intrinsic value of non-unique, Martian microorganisms. Meanwhile, places like Enceladus, Europa, Ceres, or other places thought or known to contain life could be placed off-limits to human visitation without a permit since they are less valuable as habitats for humans.

That doesn't mean that reasonable steps shouldn't be undertaken to avoid the extinction of Martian microorganisms, which raises the prickly question of whether terraforming should be undertaken, given the existence of Martian microorganisms. If the case could be made that terraforming would not cause the extinction of Martian microorganisms, then by all means go for it if you really want.

Yes, a cosmocentric ethic argues that Mars as it is is intrinsically valuable and that it as it is should not be destroyed without a very good reason. But in this case, the value of a terraformed Mars + human culture outweighs the intrinsic value of the primitive Mars.
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline robertinventor

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My take (YMMV):

In the unlikely event there are macroorganisms on Mars, e.g., those lichens some people say (99% sure they are not real myself, nevertheless...) then the planet should be quarantined. Only scientists should be allowed to visit at least until we know for sure that human colonies would not cause their extinction. These would be truly unique specimens, and should be allowed to evolve unmolested.

The more likely scenario is that there is life, but it is microbial life confined to briny aquifers below the surface. If these organisms are able to exist in Mars's perchlorate-infested, poisonous ecosystem, then they are going to be very hardy creatures and unlikely to be displaced by microbes brought in accidently from Earth. After all, it's likely that there has been occasional transfers of life between the two planets in the past.
I answer that in the article actually. Think about Australia. There has been a lot of exchange of life, after all not so long ago geologically speaking all our continents were part of one big super continent (200 million years ago as Pangea).

The life there is ideally adapted to its environment, as far as it goes, but for some reason placental animals never developed there. So the introduced life from Europe, although the Australian conditions were new to them, were able to thrive there and e.g. the Tasmanian wolf driven extinct, and many habitats and species under threat.

Actually the timing is rather similar, Gondwanaland broke up 184 million years ago and Australia separated from Antarctica 80 million years ago.
http://en.wikipedia.org/wiki/Gondwana#Breakup

As far as I know (correct me if anyone knows of a more recent one), the last major ejection of Earth material to Mars, which might (no certainty at all) have brought Earth life to Mars was probably the impact about 66 million years ago the date of the Chicxulub crater (only the very largest impacts send material up through the atmosphere at over escape velocity, asteroids of about 10 km or larger, and then most of the material takes millions of years to reach Mars, which some extremely hardy extremophiles may be able to survive).
http://en.wikipedia.org/wiki/Chicxulub_crater

For extremophiles, the Mars habitat is not that different from habitats on Earth, not like e.g. Titan where if there is life there, the chances of Earth life being able to thrive there at all is remote in the extreme (at least as far as I know :) ). Even briefly goes above 0c on the surface every day in many locations on Mars.
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Yes, this option is risky, I admit, but if there are microorganisms on Mars, it's likely that they are practically everywhere in the solar system where there is liquid water; therefore, in the unlikely event that Martian life were to be caused to go extinct, other forms of extraterrestrial life would persist elsewhere.
Yes that's possible. Similarly if all the marsupial life in Australia went extinct, you would still have e.g. the tree Kangaroos of Indonesia (assuming they survive) so some marsupials would still survive.

The thing is that the Mars life may be unique to Mars, almost certainly is.

Then amongst all those other locations, Mars is special because it is such a near twin to the early Earth, with its early history preserved much better than on Earth, so we can learn a lot about our planet, which currently is the only place where life is known to have evolved.

And at this stage it is all guesses anyway. Who knows yes might turn out that e.g. Encladus is the rossetta stone we are seeking and that life on Mars is just the same as all the other life in the solar system, and that there is nothing interesting on Mars to make it worth preserving and even the early life deposits are uninteresting, nowhere near the expected promise, and no-one cares what happens to them biologically.

I'd be surprised if that happens but who knows at this stage. But that's the point really. We simply have nowhere near enough information to make such a big irreversible decision about Mars. And there is plenty of indirect evidence to suggest that Mars may be of immense interest. Encladus and Europa probably too, but in a different way.
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That doesn't mean that reasonable steps shouldn't be undertaken to avoid the extinction of Martian microorganisms, which raises the prickly question of whether terraforming should be undertaken, given the existence of Martian microorganisms. If the case could be made that terraforming would not cause the extinction of Martian microorganisms, then by all means go for it if you really want.

Yes, a cosmocentric ethic argues that Mars as it is is intrinsically valuable and that it as it is should not be destroyed without a very good reason. But in this case, the value of a terraformed Mars + human culture outweighs the intrinsic value of the primitive Mars.

I'd agree there if the case was made successfully. There is also the prickly question of whether terraforming is actually prevented by adding aerobes to the planet at too early a stage.

See my article here about the tricky question of whether and how to terraform Mars

http://robert-inventor.tumblr.com/post/49677771359/terraforming-mars-needs-great-care-it-is-far-too

The big thing though is, do we have enough information to debate this question. I would say nowhere near enough yet.

When the great debate happens then there will be many people arguing different points of view. The unique thing about the view of those that jump in and land there right away is that their approach is irreversible, once you have done it you can't undo it. That's why I think the present law that makes that illegal should continue for a fair while yet, until we really and truly understand Mars from a biological point of view at least reasonably well.
« Last Edit: 05/15/2013 08:09 PM by robertinventor »

Online Jim Davis

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And yes, I fully admit that causing extinctions of any kind is an intrinsic moral wrong...

The eradication of smallpox was an intrinsic moral wrong?

Offline rcoppola

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A bit of Human arrogance in all of this.

Earth, like Mars, has and will forever be impacted by forces much greater then humankind. Earth has been made then re-made, re-shaped, frozen, heated, etc., with mass life-eruptions and mass life-extinctions well before us and will continue well after us until the sun goes super-nova and swallows up the entire solar system.

Not to say we shouldn't exercise care with regards to how we impact both our earthly and celestial environments. But let's not go about thinking we are all that either.
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Offline gospacex

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What is the problem with studying Mars while it is being colonized?

Contamination argument doesn't hold water: Genesis probe crashed on landing, contaminating all samples; yet, scientists aren't as dumb as some might think. They managed to sort out contamination from the samples. I don't see why a bit of ingenuity wouldn't help scientists to unravel Mars mysteries even if some "evil Earth bacteria" contaminate Mars soil.

But it does. Why do you think they are so careful to prevent contamination of Mars with the unmanned rovers? Why do you think the Outer Space Treaty has a specific clause preventing this, and the COSPAR guidelines classify Mars as Category IV?

Yes, with a small sample and a lot of work, in a situation where a lot of scientists working on a small amount of material is cost effective because it is so expensive to get more of it, and where you are not looking for life itself, just for a way of separating out individual dust grains that are of cometary origin from those of desert origin, then you can do it.

Why the same can't be done on Mars?

Scientists on Earth managed to learn quite a bit about past history of Earth's life, despite _billions of years_ of constant erasing and rewriting by newer generations.

You are saying that on Mars, scientists will be much dumber and won't find a way to differentiate Earth bacteria from Mars ones.

I am plain out not buying it.

Next. Let's say for the sake of argument that indeed, Mars colonization can irreversibly erase enough evidence so that we won't find out some information about Mars. Say, we won't know whether the bacteria we see are genuine Martian ones or are from Earth. As I said, I don't believe in this happening, but suppose it will be so.

Newsflash! Nothing particularly horrible will happen because of this. No one will die. Just like we don't know some details about Earth's past, and its not killing us.

Try to get some perspective. If something is upsetting *you* a lot as a scientist, doesn't automatically mean it is a Galactic emergency.

I personally are far more outraged that right this very moment actual concentration camps are functioning on this planet, people are dying there and we do nothing, than fate of some theoretical Mars bacteria!

Offline gospacex

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And yes, I fully admit that causing extinctions of any kind is an intrinsic moral wrong...

The eradication of smallpox was an intrinsic moral wrong?

I just don't know how Warren manages to brush his teeth in the morning. Millions are dying ;)

Offline guckyfan

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There are two possibilities. Maybe we can't distinguish Mars life from imported earth life. In that case Mars life would not give us much information. Mars and Earth life would likely have common origin.

But if Mars life originated independently, there will be differences we can detect and that would be the great find on Mars. It would mean that life will evolve most everywhere, if the conditions are there. BTW that is what I personally believe but would like to be proven. So lets go and find out.

Offline SpacexULA

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We are likely going to be in a robotic only exploration mode on Mars for at minimum for the next 1-3 decades.  During this time I think we should continue with internationally agreed upon practice sterilizing to the maximum extent practical the spacecraft.

On the other hand, as soon as we start landing humans on Mars or any other body in the solar system, we are going to have scrapyards and landfills.

I personally can't wait for the day the New Moon is a thing of the past you can see the lights on human inhabitation on the Moon on a clear night.



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Offline rklaehn

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What I say in the article though is that in space you can create living areas for a hundred or a thousand times the population of Earth. In Ceres alone there is enough material for habitats with total living area at least hundreds of times that of Earth.

A lot of smart people seem to think that mars is our best hope to establish a self-sustaining colony off earth and that creating self-sustaining colonies in free space is basically impossible with current technology, while establishing a colony on mars is just barely possible with current or near-term technology.

Prove them wrong by establishing a self-sustaining O'Neill-style colony, and you would have an argument for keeping mars pristine. But as long as mars is the only borderline habitable place in the solar system other than earth, making the life we know to exist on earth multiplanetary is much more important than preserving some hypothetical indigenous mars life.
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Offline robertinventor

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Why the same can't be done on Mars?

Scientists on Earth managed to learn quite a bit about past history of Earth's life, despite _billions of years_ of constant erasing and rewriting by newer generations.

That's true up to a point. But about the origins of life, then they know almost nothing. Their knowledge is okay for recent past. Further back you get a few hot spots like the Burgess shale where by chance a lot of species are preserved giving an amazing but brief snapshot of life at one particular moment in the Middle Cambrian - but for much of the past there just isn't anything preserved of exactly that age to study. They are great at teasing out information from tiny clues and small fragments of material.

But for a lot of the early history there is nothing that survives especially evidence for life. When you get back to the very early dates, there is almost no geological material, and no life fossils at all. When you have no evidence, you can't tease interesting information out, you can't tease nothing out of nothing.

So for instance the oldest dated  terrestial material is 4.4 billion years old

http://en.wikipedia.org/wiki/Oldest_dated_rocks#Oldest_terrestrial_material

Pretty good, except, that it is just a tiny fragment of zircon, embedded in a rock formation.

The late heavy bombardment ended 3.8 billion yearse ago
http://en.wikipedia.org/wiki/Late_Heavy_Bombardment

Life could have started any time after that. Actually it could have started during it too, and I've also seen a paper with speculation that it could have started on Earth before the collision that created the Moon (4.5 billion years ago), with debris from the Earth reseeding it with life again after the collision.

Or indeed, it could have started on Mars and seeded Earth- that's another serious contender that I've seen in the publications on this subject - since Mars cooled down before Earth, no Moon forming impact, as clement as the Earth to start with, so may have got off to an earlier start than Earth as far as life is concerned.

The oldest controversial fossils are from 3.5 billion years ago
http://en.wikipedia.org/wiki/Evolutionary_history_of_life#Earliest_evidence_for_life_on_Earth

The oldest rock formation is possibly this one 3.4 billion years old
http://en.wikipedia.org/wiki/Baltic_Shield

So for maybe 300 million years, and could be a lot longer, then there is no evidence at all. Not organics, wouldn't expect that here on Earth as it is too warm, and plenty of life and many processes to metamorphose it. But there is no evidence at all, no microfossils, nothing even giving a slight clue as to what the life was like in those days.

These are some of the ideas, but not much hope of deciding between them, so far anyway:

http://en.wikipedia.org/wiki/Evolutionary_history_of_life#Origins_of_life_on_Earth

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You are saying that on Mars, scientists will be much dumber and won't find a way to differentiate Earth bacteria from Mars ones.

I am plain out not buying it.

Well I've answered that already, obviously my answers weren't convincing so won't try again.

But, what is your explanation for the Outer Space Treaty and the COSPAR guidelines?

Do you think the scientists are just confused and that they didn't need to worry at all about contaminating Mars?

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Newsflash! Nothing particularly horrible will happen because of this. No one will die. Just like we don't know some details about Earth's past, and its not killing us.

It's more the other way around, the knowledge that is lost.

Like e.g. if you had a possibility to find some wonderful buried treasure, detect it with a metal detector, dig it up, and see it gleaming, then come back the next day and it is gone. And not just that it is gone, but that it was removed by a buldozer that just tipped it into the sea, so no-one got it.

It's a bit like that.

Nothing terrible happened to you but you wouldn't be a happy chap :).

Now imagine that that buried treasure is not just a one off thing but something of value for generations of people into the future, that they will keep finding new treasures there, but someone buldozed it all away.

That might help you understand how the scientists feel about this a bit. And not just of value to scientists, but to all humanity through the inventions and materials and so on that might flow out of it if it is as interesting and illuminating as it seems it might be.

Actually there are also concerns about things that could go wrong, backward contamination from colonists having bad effects on the Earth ecosystem, also forward contamination of Mars making it inhospitable for humans. But I think better to just focus on the positive for now since that is easy to see and pretty non controversial. So I focused on the positive value of a Pristine Mars in that post. Have said a bit about the contamination issues in other posts.
« Last Edit: 05/16/2013 03:43 AM by robertinventor »

Offline robertinventor

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A lot of smart people seem to think that mars is our best hope to establish a self-sustaining colony off earth and that creating self-sustaining colonies in free space is basically impossible with current technology, while establishing a colony on mars is just barely possible with current or near-term technology.

Prove them wrong by establishing a self-sustaining O'Neill-style colony, and you would have an argument for keeping mars pristine. But as long as mars is the only borderline habitable place in the solar system other than earth, making the life we know to exist on earth multiplanetary is much more important than preserving some hypothetical indigenous mars life.

Oh I agree, I know some pretty smart people are keen on Mars surface colonization, especially Robert Zubrin. I've learnt though that smart people aren't always right. Even experts, there are things they didn't know, or they took a judgement call on something that no-one knew one way or the other at the time, and got proved wrong, it happens.

You can't say that because someone is very bright, therefore they are right. Not in a field like this with so many unknowns, and with many smart people on all sides of the debate.

I don't know of anyone actually saying that it is the only place to colonize though. Does anyone say that?

Even if you thought that space colonies wouldn't work for some reason, the Moon particularly is a natural place to start colonization, and hard to find anything wrong with it except those who say "boring we've been there already" :).

And to say humans can't live in space when we have the ISS with people living there for months on end.... Does anyone say that? Of course the ISS is not designed for long term living and colonization, you get bone loss due to the weightlessness, and it needs a centrifuge habitat at minimum.

There is a plan to possibly fly a centrifuge to the ISS to use as sleeping quarters for the astronauts actually. It's testing technology that would be used for interplanetary travel.

The ISS has lots of problems e.g. with environmental control, that needed to be surmounted. And it is not self contained by any means.

So, it is just a first step towards that. But the challenges are almost the same on Mars surface as in space. You are going to need to deal all those issues of removing contaminants from the air such as skin flakes, hair, build up of harmful airborne micro-organisms, ammonia, acetone, nitrogen dioxide, and to regenerate oxygen, scrub CO2, maintain temperature, maintain humidity, maintain atmospheric pressure, etc etc.

One or two things that are slightly easier on surface of a planet with water available don't need to worry about recycling the water quite so much possibly especially if you totally don't care about contamination issues. But basically you have to deal with something like 80% of the issues you have on a space station.

You also have some unique problems for Mars itself. For instance the Mars dust, and the sun obscured during dust storms, issues for e.g. solar panels, and for any plants you grow.

Here is a great article on the similarities and differences of Moon and Mars surface mission requirements. Only briefly mentions contamination issues, but rest is pretty thorough.

http://mepag.nasa.gov/reports/MFLO_WhitePaper_v12.pdf

This one is all about lunar contamination issues, series of slides for a presentation
http://www.lpi.usra.edu/meetings/LEA/presentations/tues_pm/Dworkin.pdf

BTW I'm not saying to make a big O'Neill type colony right away. There are lots of smaller things you can do first. The simplest is perhaps just like the ISS but add a centrifuge for sleeping in as for the Nautilus X.
http://en.wikipedia.org/wiki/Nautilus-X

Other ideas include a spaceship attached to its rocket motor and just spin them end on end, a simple design doesn't need much development.

Then the Bolas idea, two spacecraft joined by a tether, doesn't need to be that strong for gravity, just strong enough to hold the weight of the spaceship + inhabitants against the pull of Earth gravity, just a normal heavy duty cable would do that. Probably several for redundancy.

Starting small can try several of these ideas and see what scales up.

Lots of other ideas such as the modular beaded habitats, some of them here:

http://en.wikipedia.org/wiki/Space_habitat#Designs.2Fsolutions

Who knows what the final winning design or designs will be for larger and larger space stations...

But this is going off topic, possibly should start a new thread if we want to discuss that. Okay by me if you want to, leave a note here so I know.
« Last Edit: 05/16/2013 12:58 AM by robertinventor »

Offline gospacex

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Newsflash! Nothing particularly horrible will happen because of this. No one will die. Just like we don't know some details about Earth's past, and its not killing us.

It's more the other way around, the knowledge that is lost.

Like e.g. if you had a possibility to find some wonderful buried treasure, detect it with a metal detector, dig it up, and see it gleaming, then come back the next day and it is gone. And not just that it is gone, but that it was removed by a buldozer that just tipped it into the sea, so no-one got it.

It's a bit like that.

Nothing terrible happened to you but you wouldn't be a happy chap :).

Now imagine that that buried treasure is not just a one off thing but something of value for generations of people into the future, that they will keep finding new treasures there, but someone buldozed it all away.

That might help you understand how the scientists feel about this a bit. And not just of value to scientists, but to all humanity through the inventions and materials and so on that might flow out of it if it is as interesting and illuminating as it seems it might be.

Inventions and materials can be invented from knowing whether live was, or wasn't created on Mars 4 billion years ago?

I have serious doubts about that.

It's more like this: paleontologists, over last century, changed their opinion several times about where exactly birds appeared on evolutionary tree, and *nobody outside their discipline cared much about it*.

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Actually there are also concerns about things that could go wrong, backward contamination from colonists having bad effects on the Earth ecosystem, also forward contamination of Mars making it inhospitable for humans.

More unfounded hysterionics.

Offline gospacex

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Even if you thought that space colonies wouldn't work for some reason, the Moon particularly is a natural place to start colonization, and hard to find anything wrong with it except those who say "boring we've been there already" :).

No, Moon does have drawbacks compared to Mars. Moon has no atmosphere and much less volatiles.

I am also appalled by your blatant disregard to the possible destruction of indigenous Moon life by evil human colonists. ;)
« Last Edit: 05/16/2013 01:24 AM by gospacex »

Offline QuantumG

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Even if you thought that space colonies wouldn't work for some reason, the Moon particularly is a natural place to start colonization, and hard to find anything wrong with it except those who say "boring we've been there already" :).

No, Moon does have drawbacks compared to Mars. Moon has no atmosphere and much less volatiles.

I advocate both, but on this forum we prefer people advocate for colonizing the Moon, in the appropriate section, so as not to continue having the same tired argument over and over again.

I hear those things are awfully loud. It glides as softly as a cloud. What's it called? Monowhale!

Offline robertinventor

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No, Moon does have drawbacks compared to Mars. Moon has no atmosphere and much less volatiles.
Yes of course I know it has no atmosphere. But the Mars atmosphere is mainly CO2, not the most useful of gases for humans as we breath the stuff out and are continually turning oxygen into CO2. And it is very thin, try pumping air out of an atmosphere that is already a vacuum, into a habitat at Earth normal pressure, it's not going to be that easy to get it into the hab.

Especially with water on the Moon, then I don't see CO2 as a great advantage of Mars. Except of course for generation of fuel such as methane along with oxygen to burn the methane.

Longer term, most of the Moon regolith is completely dry. So in that respect for large colonies it needs to import volatiles or find a way of extracting them from the lunar regolith.

But short term it may well have everything that is needed just like Mars.

For space colonies, then there may well be everything you need on the NEOs and on Deimos or Phobos. Our knowledge isn't as good as it is for Mars. But on what we know so far may well be.
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I am also appalled by your blatant disregard to the possible destruction of indigenous Moon life by evil human colonists. ;)

:)

Actually if you read that second presentation, there is concern about lunar contamination :). It is category II which means there is some concern, unlike category I where there is no concern at all, but not currently considered enough to prevent colonization.

Not so much concern with life reproducing there and contaminating the whole of the Moon. More localized, that you might be interested, say in a particular deposit of ice on the Moon, or a particular rock formation on the surface, or, say, a meteorite that you suspect came from the Early Earth, and find that someone has contaminated it by landing a rocket next to it (rocket fumes) or that waste from a habitat has contaminated it, or such like.

Offline QuantumG

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Yes of course I know it has no atmosphere. But the Mars atmosphere is mainly CO2, not the most useful of gases for humans as we breath the stuff out and are continually turning oxygen into CO2.

It's particularly useful for plants.......

I hear those things are awfully loud. It glides as softly as a cloud. What's it called? Monowhale!

Offline robertinventor

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I advocate both, but on this forum we prefer people advocate for colonizing the Moon, in the appropriate section, so as not to continue having the same tired argument over and over again.
Okay sorry about that, posted at the same time as you. I've said all that needs to be said on the matter probably for its relevance to the issue of keeping the Mars surface pristine.

Offline robertinventor

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Inventions and materials can be invented from knowing whether live was, or wasn't created on Mars 4 billion years ago?
Of course. Many have.

It's more like this: paleontologists, over last century, changed their opinion several times about where exactly birds appeared on evolutionary tree, and *nobody outside their discipline cared much about it*.

Well this is rather more fundamental. To do with how it is possible for things to reproduce, to do with possibly completely different organization of cells on the cellular level etc.

Also to do with intermediate stages between the things we can create from simulations of early life and the most primitive forms of life we know of. There is a huge gap in between. No-one knows how you can go from non living precursors to life.

There are plenty of theories, but in the labs all they have done are things like create amino acids, and things that look a bit like cell structures but aren't. Nowhere near being able to create life in this way or evolve life out of non life. Even primitive cells are vastly complex from this point of view and it is hard to see how they ever arose in the first place and none of the theories really explains it, they involve a fair bit of hand waving :).

If modern Mars life is just like ours, in almost all respects, just slightly different type of extremophile, maybe that might be like your bird fossils, of great interest to scientists researching into evolution of micro-organisms but maybe not many others.

The early life though - that's likely to be unique in my opinion, knowledge we probably won't get for some centuries by any other method and fundamental to understanding of biology and evolution. Filling huge gaps in our understanding where at the moment we have nothing at all.

Not guaranteeing it. Just saying, let's wait and see what happens, seems a good chance that it will be like that, on the face of it seems even an excellent chance of it, let's give the scientists a chance to find out.
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Actually there are also concerns about things that could go wrong, backward contamination from colonists having bad effects on the Earth ecosystem, also forward contamination of Mars making it inhospitable for humans.

More unfounded hysterionics.

I suspect you are bating me :).

Anyway - well already mentioned the terraforming concerns. But apart from that - well the thing is - that life on Mars could have followed a different evolutionary pathway from on Earth. Just as European placental animals overran Australia, so the Earth micro-organisms could overrun Mars.

But it could go the other way around maybe it's the Mars micro-organisms that are the equivalent of the rabbits in Australia. If that is the case then they could overrun the Earth, e.g. spoil crops, or replace some micro-organism on Earth, or even find that they can live in humans, on our skin perhaps, or in our lungs or whatever. Or they could create allergens that can be a nuisance or even fatal to humans. Don't need to be well adapted to us to do that. Also can even live inside us. That possibility is surely remote because it is most likely strictly anaerobic, but not considered to be impossible.

Just because life on Mars is obviously sparse, doesn't mean it hasn't perhaps explored some pathway and adaptation that no life on Earth has done to date.

There are plenty of anaerobic environments on Earth where it could do serious harm. Also if descended from an Earth microbe millions of years ago, it might already have adaptations to Earth environment, for instance able to at least tolerate oxygen, and maybe even use it through some ancient capability, an adaptation of a polyextremophile from Earth that got to Mars and returned again to Earth,

This seems actually rather likely to me, if that is what happened - as if it was a micro-organis to Mars on a meteorite fragment, and also survived and reproduced on Mars when it got there, very different environment from the one it came from, presumably it is pretty hardy and flexible, and might well be one of those polyextremophiles.

For that matter, there is oxygen on the surface of Mars too, lots of free oxygen on the surface, all those peroxides. Perhaps aerobes can somehow utilize that. Also Martian micro-organisms even if they don't actually use it will probably have adaptations to prevent themselves being harmed by it which you'd think would help with tolerance of oxygen in our atmosphere.

Then it could also be based on novel life chemistry. This is the most interesting of all but also the one fraught with unknowns. It might do anything, and again it obviously then would have explored a pathway that Earth life hasn't. You can't guarantee that the Earth life solution is the better one or that Earth life will always out-compete it.

This is just handwaving, because no-one can know at this stage. But by the precautionary principle, then it is not for me to prove it conclusively.

It is for those who advocate colonization to show that beyond reasonable doubt it can't possibly happen. With so much at stake, the level of confidence has to be very high to convince those who are concerned about the issue. As Carl Sagan said, " The likelihood that such pathogens exist is probably small, but we cannot take even a small risk with a billion lives."

Oh and for forward contamination making it inhospitable for humans - could be e.g. methanogens get established so strongly they create a methane rich atmosphere that humans can't tolerate and that it turns out to be impossible to reverse it.

Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Just to give an idea of some of the things you can think about. Chances are that it would be something no-one has anticipated, that could happen too.

Hope that is enough to answer your question for now, and again can start a new topic on this if it is thought a good idea.


« Last Edit: 05/16/2013 03:18 AM by robertinventor »

Offline Vultur

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The early life though - that's likely to be unique in my opinion, knowledge we probably won't get for some centuries by any other method and fundamental to understanding of biology and evolution. Filling huge gaps in our understanding where at the moment we have nothing at all.

I severely doubt we will find early life on Mars. If there is life there, it will be specialized life highly adapted to the current harsh conditions on Mars, no closer to abiogenesis than modern Earth microbes.


Finding life on Mars would be hugely scientifically valuable... but not because of abiogenesis.

Also, I expect Mars life, if any, to be deep (probably endolithic), nearly undetectable (we didn't start finding these things on EARTH until, I think, the 80s) and basically unaffected by anything done on the surface. Only the methane findings give me any hope for life that actually interacts with the surface/atmosphere - the lack of liquid water seems pretty much a killer for surface life.

---

Re back contamination: the big question here is -

Why don't we worry about scientists in Antarctica bringing back plagues from microbes living in the ice/rocks? Well, because it's incredibly, fantastically unlikely. Plagues from Mars are even more so (Antarctica is a much more "Earthlike" environment, having 21% oxygen, etc.)

As for rabbits and Australia - Europe and Australia are, on this scale, basically identical environments. Same atmosphere, somewhat hotter temperatures, basically similar biota (angiosperm dominated flora, insects everywhere, birds, mammals etc.). Not so for Earth vs Mars.

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Just because life on Mars is obviously sparse, doesn't mean it hasn't perhaps explored some pathway and adaptation that no life on Earth has done to date.

They probably would have unique adaptations. But they'd be adaptations to cold, briny, high perchlorate, etc environments. Not human environments.


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Also if descended from an Earth microbe millions of years ago, it might already have adaptations to Earth environment, for instance able to at least tolerate oxygen, and maybe even use it through some ancient capability, an adaptation of a polyextremophile from Earth that got to Mars and returned again to Earth,

Sure. But by the very fact of being adapted to survive at Mars, it will be worse adapted to survival on Earth than its Earthly ancestor. If one microbe could be awesome at surviving in every condition, Earth would have only a few species.

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For that matter, there is oxygen on the surface of Mars too, lots of free oxygen on the surface, all those peroxides.

No. "Free oxygen" means not chemically bound to other elements, O2. Not the same thing at all.

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Perhaps aerobes can somehow utilize that.

A peroxide-aerobe might exist, but it would not thus be able to use atmospheric O2.


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Oh and for forward contamination making it inhospitable for humans - could be e.g. methanogens get established so strongly they create a methane rich atmosphere that humans can't tolerate and that it turns out to be impossible to reverse it.

A) There's not enough resources on Mars as it is now for life to exist at that sort of density.

B) It would be no worse than Mars' current, already unbreathable atmosphere.

C) A methane-rich atmosphere would be fairly easy to reverse, on the scale of terraforming attempts (all incredibly hard). Liberate oxygen from oxides in soil, burn the methane, it becomes CO2.

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Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.

Mars, due to its hostile-to-life nature, would be far less dangerous disease-wise than, say, living in a rainforest in Africa with non-human primates (source of AIDS, Ebola virus, Marburg virus, and a bunch of other hemorrhagic viruses and other nasty things). Or living in an area with livestock (most of the classic historical really bad diseases, cholera, smallpox, etc. jumped over from livestock) or rats (source of bubonic plague) or...

« Last Edit: 05/16/2013 04:02 AM by Vultur »

Offline kkattula

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I'm all in favour of taking reasonable steps to preserve the science, but as is often the case, what's the definition of reasonable?
 
For some scientists searching for present or past evidence of life, reasonable is clearly no Earth life (including humans) should be knowingly introduced to the Mars environment until they're sure there's no indigenous life, or ever if they find actually find some.
 
My problem with this approach is twofold:
 
1)  Mars is not a pristine environment. As the OP has acknowledged, there is already the possibility of cross contamination with Earth through natural processes. Plus the probes landed/crashed over the last 40 years were not perfectly sterile.
 
2) Diminishing scientific returns. Remote, even tele-presence exploration is unlikely to find life unless it's both very common and close to the surface. If it isn't found by examining a few different sites over a couple of years, 50 years is probably not going to make a difference either. You can't prove it doesn't exist by not finding it. Only the opposite.
 
So by all means start with tele-presence, perhaps by exploring an area before remotely building a landing base there for human surface operations. And for a long while keep track of where humans go on the surface, with careful protocols for sample collection to avoid unnecessary contamination.
 
But to indefinitely quarantine an entire planet? On the faint possibility that if there is life there we wouldn't be able distinguish it from life brought by humans? That's an argument for never going anywhere or doing anything. Even robotic exploration is subject to the Observer Effect.
 
We are life. Our core purpose is to spread our genetic pattern as far and wide as possible for as long as possible. That could be considered the ultimate morality. Intelligence and science are just tools we've evolved to aid that purpose. Placing science ahead of species would therefore be immoral.
 
 
 

Offline robertinventor

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I severely doubt we will find early life on Mars. If there is life there, it will be specialized life highly adapted to the current harsh conditions on Mars, no closer to abiogenesis than modern Earth microbes.

Finding life on Mars would be hugely scientifically valuable... but not because of abiogenesis.
Did you follow my reasoning for it? That in the first few hundred million years after formation, Mars was a near twin to Earth. That it had organics from the comets just like Earth. Indeed to this day Mars should have a lot of organics on its surface due to impact of comets and meteorites and it is a bit of a mystery why there isn't as much as expected.

Do you know about the attempts at simulating early earth in a laboratory? For instance the Miller Urey experiment.
http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
Or  the experiments that create cell like structures, protobionts, non living but cell like, in a similar way?
http://en.wikipedia.org/wiki/Protobionts
At the minimum, early Mars is a giant version of one of those experiments.

If there was no life evolved in early Mars then that is a big puzzle too. If it doesn't even produce protobionts and rich amounts of amino acids then there is a lot of explaining to be done.

You could be right and you are entitled to your view. I said that one possibility is that Mars turns out to be totally boring and uninteresting for life. Maybe there is something that makes it so different from Earth that nothing could happen at all like the early Earth processes. But on evidence so far including what Curiosity has found so far, seems an excellent chance that it is interesting. And for scientists that would be a more interesting future if it is, and might well have all those practical and technological benefits for us too.
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Also, I expect Mars life, if any, to be deep (probably endolithic), nearly undetectable (we didn't start finding these things on EARTH until, I think, the 80s) and basically unaffected by anything done on the surface. Only the methane findings give me any hope for life that actually interacts with the surface/atmosphere - the lack of liquid water seems pretty much a killer for surface life.

That was the consensus about 10 years ago. Nowadays though there are several possible habitats on or near the surface. There is the possibility of thin films of salty brine just below the surface warmed by the sun at midday. There is the possibility of snow melting around grains of dust in the sun. There is the possibility of geologically ancient deep ice sheets in the equatorial region that gradually migrate upwards through sublimation and may give a source of moisture when they reach the surface. There is the possibility of life tens of meters deep in the polar ice sheets. There is a possibility of some slow growing lichen type plant that utilizes the moisture in the morning and evening dews. There's the possibility also of life that is in dormant state but "wakes up" to use water that is created during polar meteoroid or comet impacts with Mars that may create under ice lakes that last for a millennia or two under a surface of ice before they freeze up again. These are all possibilities that have been suggested in recent papers since 2000.

Then there are the deep habitats you mention too. At a certain depth then liquid water may be present on Mars due to geothermal heating. It may be prevented from evaporating by a thick layer of ice above it. These would be hard to detect without really deep drilling.

There may also be closer to the surface habitats due to geothermal heating, similar idea but due to localise heating closer to the surface - again harder to detect because if close to the surface must still be prevented from evaporation by some overlying impermeable layer, but may be accessible in caves or by drilling.

That the atmosphere is in equilibrium suggests that these habitats don't support much life, the ones with contact with the surface atmosphere at least. But they might just be very sparsely populated with life, because the total volume of the habitat is low, as it is in some of these examples. The deeper habitats may have abundant life for all we know. The deeper habitats may get exposed to the surface as result of meteoritic impact on Mars, but some may be kms deep and hard to access.

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Re back contamination: the big question here is -

Why don't we worry about scientists in Antarctica bringing back plagues from microbes living in the ice/rocks? Well, because it's incredibly, fantastically unlikely. Plagues from Mars are even more so (Antarctica is a much more "Earthlike" environment, having 21% oxygen, etc.)
Antarctica has been in communication with the rest of Earth for many micro-organisms as you can tell as there are micro-organisms in Antarctica that also exist in many other locations on Earth. For instance radiodurans, found in Antarctica but also found in soil, clothes etc (it's one of the polyextremophiles).

Continents are far less isolated for micro-organisms than they are for higher animals and plants. Especially the micro-organisms with dormant states that are highly resistant to dessication, radiation etc.

Also all the continents were merged in a super continent 80 million years or so ago. Most life on Mars if it exists has probably evolved independently from Earth for at least billions of years, even if some extremophile species was transferred more recently like a few tens of million years ago.

We have nowhere on Earth to compare with Mars as an analogue for its level of isolation from the rest of microbial life on Earth.
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As for rabbits and Australia - Europe and Australia are, on this scale, basically identical environments. Same atmosphere, somewhat hotter temperatures, basically similar biota (angiosperm dominated flora, insects everywhere, birds, mammals etc.). Not so for Earth vs Mars.
For micro-organisms, many are primary producers. They just need water, rock, some source of energy to survive and reproduce. For them, Mars is similar enough to Earth so it is though they could easily survive in some of these habitats on Mars if they exist.

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Just because life on Mars is obviously sparse, doesn't mean it hasn't perhaps explored some pathway and adaptation that no life on Earth has done to date.

They probably would have unique adaptations. But they'd be adaptations to cold, briny, high perchlorate, etc environments. Not human environments.
First, cold briny environments do exist on Earth. Then just because they can survive in cold briny environments doesn't mean that they can't survive in room temperature environments. All it means is they have adaptations that permit survival at lower temperatures. They might find higher temperatures more to their liking even.

If descended from life that evolved in much warmer environments e.g. volcanic vents etc they may well be polyextremophiles capable of surviving even at extremely high temperatures, or ditto if descended from polyextremophiles that survived the journey to Mars on a meteorite.
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> Also if descended from an Earth microbe millions of years ago, it might already have adaptations to Earth environment, for instance able to at least tolerate oxygen, and maybe even use it through some ancient capability, an adaptation of a polyextremophile from Earth that got to Mars and returned again to Earth,

Sure. But by the very fact of being adapted to survive at Mars, it will be worse adapted to survival on Earth than its Earthly ancestor. If one microbe could be awesome at surviving in every condition, Earth would have only a few species.
I follow your reasoning, but it doesn't work like that in practise. There are indeed microbes on Earth such as radiodurans that are awesome as you describe. But though they are found in a huge range of environments, the populations tend to be sparse.

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> For that matter, there is oxygen on the surface of Mars too, lots of free oxygen on the surface, all those peroxides.

No. "Free oxygen" means not chemically bound to other elements, O2. Not the same thing at all.

> Perhaps aerobes can somehow utilize that.

A peroxide-aerobe might exist, but it would not thus be able to use atmospheric O2.
I just meant that it would be oxygen tolerant not necessarily use it. Anothe possibility though is some local process on Mars that liberates the oxygen creating oxygenated water for micro-organisms to use (perhaps some other form of life). That's just a thought, I don't know if there has been any research into it, just an idea I had right now.

For instance if there is hydrogen peroxide on Mars, it could simply decompose in the presence of water and oxygenate the water.

BTW found this paper on the possibility of hydrogen peroxide utilizing life on Mars just now in a google search

http://arxiv.org/ftp/physics/papers/0610/0610093.pdf
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> Oh and for forward contamination making it inhospitable for humans - could be e.g. methanogens get established so strongly they create a methane rich atmosphere that humans can't tolerate and that it turns out to be impossible to reverse it.

A) There's not enough resources on Mars as it is now for life to exist at that sort of density.

B) It would be no worse than Mars' current, already unbreathable atmosphere.

C) A methane-rich atmosphere would be fairly easy to reverse, on the scale of terraforming attempts (all incredibly hard). Liberate oxygen from oxides in soil, burn the methane, it becomes CO2.
There is a lot of CO2 on Mars. There is a lot of water. Methane is a greenhouse gas so once it starts to form it could start to warm up the planet in a runaway greenhouse effect.

Yes there is oxygen on the surface, but I'm assuming the methanogens continually use the water and CO2 to liberate methane until it is overwhelmed. Not sure that the idea can be made to work, where do they get the hydrogen from? Some other reaction or micro-organism perhaps.

This is just a thought of my own, not a published paper, should have said to make it clear. But methanogens have been hypothesized to possibly exist on Mars to explain the methane signal.

The general thought behind it is that there are many cycles that maintain our atmosphere in its current state, most mediated by life. In Mars similar cycles might get established, but ones that maintain a different atmosphere from the Earth one, which could be one not to humans liking.

That could be hard to reverse especially when we know so little about terraforming.
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> Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.
Yes. The thing is though, those diseases are dangerous to humans. For instance the way that remote uncontacted tribes in the Amazon die due to things that are trivial for us like flu.

So the thing is that we would have no immunity  to it. Not so likely to be one we can't develop immunity to, but could be one that causes a plague that only a tiny minority of humans are immune to naturally. And remote chance that it is so different that no humans have any natural immunity to it, yet still able to infect us, that's the possibility that could lead to extinction of humans. Very very low chance most would say.

The backward infection possibility everyone is in agreement is pretty unlikely. But not zero. As Carl Sagan said, should you take even a tiny chance like that with a billion lives? The precautionary principle says no. You need to show it can't happen beyond any reasonable doubt.

In this case though, I'd say perhaps it is greater likelihood though I haven't seen any published research on this topic, of human organisms developing and evolving on Mars. But - you have a very unusual situation there. You have an entire virgin planet, and you dump the human biome on it, leave it to evolve there for a decade (say) and then see what happens to it.

Seems to me intuitively that given that it is pretty certain that some of them will survive in dormant state, and that if there are habitats on Mars will reproduce there, that you are very likely to get microbes coming back that are evolved quite a bit from the original ones. I mean - mainly switching on and off genes, but possibly also new mutations as well, and if one of them finds a useful adaptation, sharing with others as micro-organisms can do. Just a rare event, with a planetary scale population (even just in micro-habitats) could happen. Then - especially on these short timescales, but also generally, micro-organisms have a great tendency to keep existing capabilities when they acquire new ones. So they may very well still be able to live on humans when they next encounter a human habitat.

That's the reasoning there. I'd be interested to know if anyone has published a paper looking into this possibility in detail. If not, is a useful line of research to follow up I think.

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Mars, due to its hostile-to-life nature, would be far less dangerous disease-wise than, say, living in a rainforest in Africa with non-human primates (source of AIDS, Ebola virus, Marburg virus, and a bunch of other hemorrhagic viruses and other nasty things). Or living in an area with livestock (most of the classic historical really bad diseases, cholera, smallpox, etc. jumped over from livestock) or rats (source of bubonic plague) or...

The difference is that we have generated immunity to those. Basically you can argue two ways here, as Carl Sagan said in his quote. You can argue that there is a low chance that the life on Mars can infect us because it is so isolated from Earth and different. But you can also argue that it is more dangerous because we lack natural immunity to whatever is there. The question is  - which of those wins out?
« Last Edit: 05/16/2013 10:36 AM by robertinventor »

Offline robertinventor

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I'm all in favour of taking reasonable steps to preserve the science, but as is often the case, what's the definition of reasonable?
 
For some scientists searching for present or past evidence of life, reasonable is clearly no Earth life (including humans) should be knowingly introduced to the Mars environment until they're sure there's no indigenous life, or ever if they find actually find some.
 
My problem with this approach is twofold:
 
1)  Mars is not a pristine environment. As the OP has acknowledged, there is already the possibility of cross contamination with Earth through natural processes. Plus the probes landed/crashed over the last 40 years were not perfectly sterile.


Yes. However there is at least a good chance  that the life our probes introduced to Mars, which they surely did, is still in a dormant state. It is hoped that it is a biologically reversible situation, that we in the future could clean up this contamination of Mars.

The life introduced by meteorites would be long ago, millions of years ago, and very few species could survive that transfer.

Here on Earth, birds can transfer easily between islands, and other animals can do so too on rafts of floating debris. Yet this is rare enough in practise that places like Australia, even e.g. India and Africa, have very different wildlife.

So a bit of transfer of micro-organisms between Earth and Mars doesn't make them identical on microorganism level.
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2) Diminishing scientific returns. Remote, even tele-presence exploration is unlikely to find life unless it's both very common and close to the surface. If it isn't found by examining a few different sites over a couple of years, 50 years is probably not going to make a difference either. You can't prove it doesn't exist by not finding it. Only the opposite.

The thing is this process hasn't even started yet. There may be dormant life forms on the rocks that Curiosity examines even, and it would be hard to tell if sparse.

You can't examine the whole planet in a short time. But you can examine representative examples of all the known habitats there. You can also drill deep, at least tens of meters deep is practical with current technology with robotic missions, there are proposals to do that that may fly quite soon. Even deeper is also possible though more on the drawing board.

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So by all means start with tele-presence, perhaps by exploring an area before remotely building a landing base there for human surface operations. And for a long while keep track of where humans go on the surface, with careful protocols for sample collection to avoid unnecessary contamination.
 

Keeping track of where humans go isn't nearly so much use on Mars as on the Moon because of the global dust storms. If the dust on Mars gets contaminated by a human base, it becomes a global contamination. The micro-organisms just need to get imbedded in cracks in the dust to be shielded well enough to survive long journeys over the surface. With the huge numbers, hundreds of trillions of micro-organisms, that a human hab will produce, seems highly likely some of those dust grains will eventually reach any surface habitat that is exposed to the dust.
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But to indefinitely quarantine an entire planet? On the faint possibility that if there is life there we wouldn't be able distinguish it from life brought by humans? That's an argument for never going anywhere or doing anything. Even robotic exploration is subject to the Observer Effect.

It is an argument for not going as humans in person to category IV destinations under COSPAR. There are many category II and category I destinations in our solar system. We can go to those.

Also a Mars flyby or orbit is Category III. That needs care too, need to be certain that the craft won't crash into the surface during the flyby as has happened with several probes to Mars that were intended for orbit. It is bad enough for those, potentially hopefully biologically reversible, but hard to see how you could biologically reverse it if a human occupied ship crashed on the surface and the bodies lay there for any length of time at all.

For instance using aerobraking in the Mars atmosphere to slow down a human spacecraft in Mars orbit seems dubious at current stage. You would have to show there is absolutely no reasonable risk that it could go wrong and end in a hard landing on Mars.

But an orbital insertion using rockets, as in some of the proposed human orbiting missions to Mars is okay, at least I'd argue for it :). And that then opens the way to those telepresence missions, and for avatars on the surface and driving rovers on the surface and all that. Though we do have to be extremely careful there for as long as Mars orbit remains category III, especially for the orbital insertion part of the trajectory to Mars.

If Mars is downgraded to category II as a result of the searches there, or if new understanding makes it possible to introduce new categories and ways of looking at things that permits exploration of Mars on the surface within the context of a whole new way of working in outer space (e.g. with terraforming as an objective or whatever), we might be able to go there on the surface.

But it is something that needs to be changed by public debate informed by scientific understanding we don't have yet. And will be decided internationally by scientists and also politicians, and not by a small group of enthusiasts for Mars colonization.

Meanwhile we can do lots of exciting stuff exploring the surface via telepresence. Yes indeed it also builds up lots of infrastructure on the surface in case humans do eventually land on the surface in the future. Carl Sagan was very optimistic that that would happen eventually. But that was a while back.

I'd love to see it from the human interest point of view as someone brought up on all the sci fi stories about Mars colonization and exploration by humans, but am not so optimistic that it is going to happen, because the most interesting case, for me, is the one where Mars is biologically fascinating and needs to be quarantined indefinitely, at least for many decades, while we study it. But exploration by avatars can help fill that gap when you can't send actual humans themselves, and the avatars give the operating humans a better view of the surface anyway, and enhanced capabilities and dexterity or strength as desired.

To go there right now as humans on the surface is against the Outer Space Treaty signed by all the nations with capabilities to launch into space.
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We are life. Our core purpose is to spread our genetic pattern as far and wide as possible for as long as possible. That could be considered the ultimate morality. Intelligence and science are just tools we've evolved to aid that purpose. Placing science ahead of species would therefore be immoral.

That is a POV. I don't share that POV.

It is not a conclusive argument. You could say it is the purpose of the gene perhaps, in a way, but not our purpose, and we are not controlled by our genes. We can make our own decisions.

Basically living organisms are underdetermined by genes. The genes don't individually code for everything we do or for all elements of our behaviour. They are broad brush things.

E.g. you don't have separate genes for empathy, for altruism, and for understanding the inner states of other living beings. Arguably as soon as a being is able to understand that others have similar feelings and thoughts to themselves, then they have the potential for empathy and altruism.

Genes can reduce the potential to appreciate what others feel or think, but by doing that reduce the ability of organisms to function well in society. Somewhere between those extremes you get our current situation where most humans are reasonably good at understanding each other, yet with much misunderstanding as well, and where empathy and altruism are common but not universal.

There is no obligation on us at all as thinking humans to reproduce as much as possible and create as many possible humans in the universe. We can make our own decisions about what to do.

« Last Edit: 05/16/2013 12:17 PM by robertinventor »

Offline robertinventor

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It seems that here only SiriusGray is broadly in agreement with me so far. Perhaps not surprising given the place where the discussion is happening, and I expected a vigorous debate here and have not been disappointed. It is great to help clarify ideas.

More generally though in other debates I find that many scientists do share my ideas, and contamination concerns about a human landing on Mars in the  near future. As indeed you can tell from all the published papers that express similar views.

If anyone does try to change the treaty to permit a human launch to the Mars surface at this present time, then on the basis of the published papers and the discussions I've had, I expect a fair amount of opposition at this stage. Would be very surprised if the law does get changed in their favour. And changing an international treaty like this is no small or simple process.
« Last Edit: 05/16/2013 11:11 AM by robertinventor »

Offline gospacex

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Yes. The thing is though, those diseases are dangerous to humans. For instance the way that remote uncontacted tribes in the Amazon die due to things that are trivial for us like flu.

So the thing is that we would have no immunity  to it. Not so likely to be one we can't develop immunity to, but could be one that causes a plague that only a tiny minority of humans are immune to naturally. And remote chance that it is so different that no humans have any natural immunity to it, yet still able to infect us, that's the possibility that could lead to extinction of humans. Very very low chance most would say.

The backward infection possibility everyone is in agreement is pretty unlikely. But not zero.

You didn't get it.

The probability of Mars bacteria to turn into superbug is much, much smaller than probability that some *Earth* bacteria will mutate into a superbug tomorrow.

If you are worrying about appearance of a superbug killing almost entire humanity, you should be advocating that we build fully autonomous sterile habitats on Earth and live in them, ASAP.

As I said in my initial post, you are an eco-extremist. You are going to buzz here repeating your POV ad nauseum, impervious to any arguments to the contrary.

Offline robertinventor

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As I said in my initial post, you are an eco-extremist. You are going to buzz here repeating your POV ad nauseum, impervious to any arguments to the contrary.

Okay, sorry you found my replies like that. It's been an interesting discussion :). I have listened to what you said. Don't want to answer your particular point you just raised, as clearly you don't want to  hear more of my POV at this stage. Fair enough.

Offline Celebrimbor

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Life's just too short for hand wringing.  Do you want to do some science on Mars or not?  If you do, you'll need to send stuff (and life) to Mars.

If it is possible for Earth based life to spread on current mars more than a few miles, then that would be interesting to know.

We need to study what we can and with urgency.  Not everyone will get what they want.

Offline robertinventor

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Life's just too short for hand wringing.  Do you want to do some science on Mars or not?  If you do, you'll need to send stuff (and life) to Mars.
That could be a conflict, yes. But the studies e.g. for HERRO show that you can actually explore the surface of Mars much more quickly via telepresence than you can with humans on the surface.

The thing is that via telepresence the humans can control several missions on the surface at once in different locations. Also they don't need to don spacesuits to start work (which takes 45 minutes in the ISS + an extra hour breathing pure oxygen before they go out).

For HERRO they estimated that the same number of humans could do roughly three times the amount of work via telepresence that they could do on the surface in spacesuits. That is also for a lower cost mission than the surface, much lower, no human rated lander needed for the surface. So the amount of extra exploration per unit cost is much more than three times.

Also that study was done some years back. Things have moved on, telepresence is more capable than it was then. So the advantage of telepresence is greater now.

And the telepresence exploration is of course more valuable to biologists as you know that the samples are uncontaminated and don't have to do controls and extra things to test for that all the time, that is if the rovers are well decontaminated.

The other thing to remember is, that the reason the current rovers are so very slow is because they are controlled from Earth. When controlled via telepresence on Mars, they will be able to be moved around at normal speeds, just as geologists do when operating machinery for remote telepresence e.g. on the ocean floor here on Earth.

If you see an interesting rock formation on the horizon, instead of planning a complex route that gets you there a month later via other interesting targets along the route, you can just drive there straight away at normal speeds.

Can use the Mars Direct plan for fuel generation on the surface, just as useful for teleoperated rovers and avatars as for humans.
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If it is possible for Earth based life to spread on current mars more than a few miles, then that would be interesting to know.

An obvious thing to do indeed is to visit the probes that have crashed there, especially the ones that were only rated as category III for decontamination, and the early Russian ones, and the crashed probes that might have had breaches of internal sealed components. And see if there are dormant spores near to them, and how far it has spread, and if it has got into the dust, and indeed, if it has moved into any actual habitat and started to reproduce.

Would be great to have some "ground truth" on all this. We can't do it yet but there are miniature scanning electron microscopes and DNA sequencers that are proposed for future missions to Mars and when those missions launch we will be able to do missions like this in a sufficiently sterilized spacecraft. There is also work on e..g hydrogen peroxide sterilization that may make it possible to sterilize spacecraft to a far higher standard without damaging the components (one of the problems in making a spacecraft rated to actually study life with high sensitivity on Mars is that obvious;y it has to have almost 0 contamination, ideally no dormant micro-organisms on it at all).


« Last Edit: 05/16/2013 12:39 PM by robertinventor »

Offline Warren Platts

And yes, I fully admit that causing extinctions of any kind is an intrinsic moral wrong...

The eradication of smallpox was an intrinsic moral wrong?

I just don't know how Warren manages to brush his teeth in the morning. Millions are dying ;)

Actually, last I checked, there are still smallpox cultures kept in select labs around the world.
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Offline Warren Platts

The more likely scenario is that there is life, but it is microbial life confined to briny aquifers below the surface. If these organisms are able to exist in Mars's perchlorate-infested, poisonous ecosystem, then they are going to be very hardy creatures and unlikely to be displaced by microbes brought in accidently from Earth. After all, it's likely that there has been occasional transfers of life between the two planets in the past.

I answer that in the article actually. Think about Australia. There has been a lot of exchange of life, after all not so long ago geologically speaking all our continents were part of one big super continent (200 million years ago as Pangea).

The life there is ideally adapted to its environment, as far as it goes, but for some reason placental animals never developed there. So the introduced life from Europe, although the Australian conditions were new to them, were able to thrive there and e.g. the Tasmanian wolf driven extinct, and many habitats and species under threat.

The Australian analogy doesn't hold. Australia is a paradise compared to Mars. A better analogy would be Antarctica. Has the endolithic algae been displaced by algae brought by humans? Nope. Similarly, we should not expect Mars microorganisms to be displaced.

I didn't know there was a treaty prohibiting human landings on Mars, though. That's funny!  ;D
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Offline robertinventor

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The Australian analogy doesn't hold. Australia is a paradise compared to Mars. A better analogy would be Antarctica. Has the endolithic algae been displaced by algae brought by humans? Nope. Similarly, we should not expect Mars microorganisms to be displaced.

Sorry, the analogy is that Australia is for higher animals like rabbits, as Mars is for micro-organisms.

Yes of course, it is easy for micro-organisms to spread around the world, except of course for the ones that are adapted to particular hosts, so diseases and parasites that can only live on a particular host are of course localized.

But other micro-organisms are found everywhere. You don't have one group of micro-organisms in Australia, another in Antarctica, and another in Europe etc as you do with the higher animals.

That's why tourists to Antarctica don't contaminate it just by landing on it. They are required to clean their boots though :).

It is really hard though for microorganisms to spread from Earth to Mars. Most can only do that if carried on a spaceship. So you may well have one group of micro-organisms here on Earth and another group on Mars that has evolved independently for billions of years. Some may be as different as the placental animals are different from marsupials, even if there is a common ancestor to them all. And some may be based on completely different life chemistry. At this stage we don't know.

Hope this helps clarify.



« Last Edit: 05/16/2013 03:44 PM by robertinventor »

Offline Warren Platts

The Australian analogy doesn't hold. Australia is a paradise compared to Mars. A better analogy would be Antarctica. Has the endolithic algae been displaced by algae brought by humans? Nope. Similarly, we should not expect Mars microorganisms to be displaced.

Sorry, the analogy is that Australia is for higher animals like rabbits, as Mars is for micro-organisms.

Yes of course, it is easy for micro-organisms to spread around the world, ...

But other micro-organisms are found everywhere. You don't have one group of micro-organisms in Australia, another in Antarctica, ...

This is simply not true: there are microorganisms endemic to Antarctica that are not found elsewhere. Yet humans have been crawling all over the continent for a century now. Yet Antarctic microorganisms haven't been driven to extinction due to introductions of exotic microorganisms. 
« Last Edit: 05/16/2013 06:17 PM by Warren Platts »
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Offline robertinventor

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Oh you are right, didn't know that. Yes there are groups of micro-organism endemic to Antarctica.

But at the same time, there is concern about the impact of human carried micro-organisms on those endemic micro-organisms too. So the parallel is closer than I realised.

Here is a report suggesting that areas of Antarctica should be identified that have not yet been touched by humans and that they are kept pristine.

http://www.scar.org:8000/treaty/atcmxxxvi/ATCM36_wp039_e.pdf

BTW I've never engaged in a discussion forum where there is quite so much throwing about of personal remarks about the motivations of the posters and personal allegations about ones moral integrity as here :).

I am acting in good faith, describing things as best I can, explaining my POV, and I have no hidden agenda, the reason for these posts is just because I care about these things.


Offline gospacex

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BTW I've never engaged in a discussion forum where there is quite so much throwing about of personal remarks about the motivations of the posters and personal allegations about ones moral integrity as here :)

Hard to believe. Internet is a quite nasty place, this forum is one of the better ones.

Quote
I am acting in good faith, describing things as best I can, explaining my POV, and I have no hidden agenda, the reason for these posts is just because I care about these things.

I don't see anyone accusing you of hidden agenda.

You indeed explained your POV, and there is nothing inherently wrong with that.

The thing is, POV is just a POV. There are many people with different POVs, and they can't be all compatible.

Some people say "we should just stay on Earth, any other place is way too inhospitable".

Others think that space colonization is a must.

Then there are fanatics of robotic exploration, of scientific exploration just for the sake of it, they really just enjoy the process itself, not it's applications for the advancement of human race.

And myriad of others. You know, some people still think that most important task is to gas all Jews.

A bizarre thing is that it's very hard to convince most of these people, even rational ones, to change their POV even by a tiny bit. They seem to be not listening.

Offline robertinventor

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I'll pass on that. Probably usually I just would take one look at the forum and decide it is not for me, or retreat after a few remarks, that's probably why I haven't encountered this sort of thing for ages, not for like a decade or more, was a member of a forum in the 1990s that was like this for a while, worse in a way.

I think people who post to forums like this get used to a particular way of expressing things. When they do things like accuse others of being an eco-extremist, or of fear mongering, or of deliberately misleading them, they don't really mean those words in the way that they would be understood in normal conversation. I don't think anyone here seriously believes that I am deliberately frightening the rest of you or deliberately misleading you, or that I am any kind of a terrorist. Just like a thing you throw out like a swear word that gets used so much it becomes meaningless.

Anyway for what it's worth seems the best thing is just to ignore such things and continue as if they weren't said. just continue with a normal conversation. It is a bit like what you do when you talk to people who swear on every second word, they don't expect you to swear back if that is not your style, and you just talk normally as you do in your own style of speaking and it works well enough..

I've done that before in forums like this, and it works pretty well. I have of course encountered it before but maybe lucky or something, not quite as much as here, not for about ten years or more.

I agree that it seems to be quite friendly here really, and that it is not intended as intimidating and unfriendly, not really, though it could be taken that way by someone not used to this.



« Last Edit: 05/16/2013 06:15 PM by robertinventor »

Offline robertinventor

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Just wanted to say, the situation is different for forward and for backward contamination.

For forward contamination then it is pretty clear that on current knowledge of Mars, if there are habitats for life there as seems quite likely, then the risk is high of those getting contaminated if you introduce loads of Earth micro-organisms to Mars.

So there you are talking about reasonably high probability events, when you bring humans into the equation. I'd be surprised if any up to date scientist researching on contamination issues, especially biologist, were to say that a human visit to Mars will not contaminate the planet, or even assign a low probability to contamination.

For backwards contamination, then you are talking about low probability events. It is reasonable yes to argue that we sometimes encounter habitats on Earth with micro-organisms that have been isolated for a long period of time. I recently read about some water discovered that was believed to be isolated for billions of years.

That is indeed an argument for saying it might not be a probable event. But then no-one thinks it is probable anyway. Not in the backward direction, mainly because Earth is so much more evolved than Mars, it seems, and teaming with life.

The thing is though, Mars is a big unknown and we really have no idea what is there at a biological level at all. In that situation our experience on Earth may be of limited value. And the consequences if we get it wrong are high indeed.

The things I said about equivalent of placental animal on micro-organism level on Mars - that wasn't meant to say that it is likely, even probable, just a possibility.

That way, the backward contamination direction, it is a very high impact event, about the highest imaginable for humans, and very low probability, everyone would agree it is almost certain that nothing will happen. But that is not the same as being sure it won't happen beyond any reasonable doubt.

Those who worry about backward contamination want to be sure beyond any reasonable doubt. To be reassured in that way we need to have some idea about whether there is life on Mars now and what form it takes, at minimum need to have had a reasonable amount of exploration using e.g. scanning electron microscopes etc. on Mars. But that is digressing a bit from this topic of keeping Mars itself pristine, we can discuss it separately.

I am in process of getting together an article on contamination issues for Mars sample return for wikipedia. It just pulls together and paraphrases or summarizes some of the things that have been published on this, including publication on the legal aspects of it, break down of the risks of the proposed mission, and so on.

Ican post it for comment if anyone is interested in a separate thread

Offline gospacex

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When they do things like accuse others of being an eco-extremist

I am sure eco-extremists don't think that they are extreme :) What's wrong with this nice idea of living in caves in peace and harmony with nature? ;)

I admit that I was wrong here: you indeed have a bit extreme views, but so far they weren't about ecology - they were about science. You think that gaining knowledge about past life on Mars trumps just about anything else, that losing some bits of it is a gigantic loss. You are scientist-extremist :)

Offline gospacex

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Mars life surviving, let alone thriving, on Earth is about as likely as Earth life surviving on Venus.

High pressure. Searing heat. Aggressive and unusual atmosphere. Good luck...

Offline Warren Platts

For forward contamination then it is pretty clear that on current knowledge of Mars, if there are habitats for life there as seems quite likely, then the risk is high of those getting contaminated if you introduce loads of Earth micro-organisms to Mars.

So there you are talking about reasonably high probability events, when you bring humans into the equation.

HOW?!? 

If there are any Mars organisms, most likely they are in deep, underground aquifers. Meanwhile, humans will be occupying the surface in self-contained, sealed habitats. Instituting some sort of decontamination procedure, like spraying down your spacesuit before you step outside would be easily doable. And if a bit of E. coli managed to get outside anyhow, it wouldn't last long in due to the UV radiation and perchlorates.


Quote
For backwards contamination, then you are talking about low probability events. ...

And the consequences if we get it wrong are high indeed.

...

everyone would agree it is almost certain that nothing will happen. But that is not the same as being sure it won't happen beyond any reasonable doubt.

Those who worry about backward contamination want to be sure beyond any reasonable doubt.

Where were you when a lot of people were worried that the LHC was going to make a black hole that was going to swallow the planet? Did you complain then? If not, what's the difference?

Also, "being almost certain" is being sure "beyond a reasonable doubt". Ever sat in on judge reading instructions to a jury? "Beyond a reasonable doubt" does not mean that there cannot be any doubt, just that such doubts aren't reasonable. Your doubts regarding the danger of back contamination are not reasonable IMHO.

In general, there about 4 standards of certainty:

1. a preponderance of the evidence (A is 1% more likely than B)

2. beyond a reasonable doubt (in practice, studies of American juries shows this works out to about 70% odds of being right)

3. reasonable certainty (e.g., truth of the principle of conservation of matter & energy)

4. absolute certainty (e.g., mathematical proof)

You're arguing that reasonable certainty ought to be applied. I actually agree, but I think we already have that level of certainty.

This is not to say that reasonable precautions shouldn't be undertaken in any case: e.g., the original LHC managers were highly irresponsible IMO when they tried to run it at full power the first time: and they paid for it with their jobs when they destroyed their machine. After they were fired, the 2nd team went for a go-slow approach, attempting to replicate earlier work first, then understanding what they're making as they gradually increased the power. Guess what? Nothing bad happened.

Similarly, I'm not recommending that we culture a bunch of Martian bacteria, load it up in tanker airplanes and spread it all over the Earth's atmosphere in order to see what happens. We simply take the ordinary steps we would take when encountering potentially dangerous microorganisms anywhere: e.g., decontaminating astronauts after they leave Mars, (they'll have a several month quarantine period on the ride back in any case), try it out on rats on Mars first to see what happens, etc.

IOW, I'll grant that the risk is non-zero; that is, we can't be absolutely certain that an Andromeda Strain scenario wouldn't unfold--but then again, we can't be absolutely certain about anything in the real world. Thus the risk of anything bad happening is minute; more importantly, it is a risk that can be managed--after all, there are several labs the world over that already deal with the most dangerous microorganisms imaginable.

The risk of back contamination certainly shouldn't be held up as justification for a moratorium on crewed Mars exploration! That's pure Chicken Little baloney! To put it politely: the argument that there should be a moratorium because of the risk of back contamination is simply unreasonable.
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline robertinventor

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if there are any Mars organisms, most likely they are in deep, underground aquifers. Meanwhile, humans will be occupying the surface in self-contained, sealed habitats. Instituting some sort of decontamination procedure, like spraying down your spacesuit before you step outside would be easily doable. And if a bit of E. coli managed to get outside anyhow, it wouldn't last long in due to the UV radiation and perchlorates.

That is what everyone thought about five years ago. Not any more though.

The thing is that dormant states of micro-organisms have been shown capable of surviving for MONTHS on Mars surface in full sunlight. And that is just a couple of species chosen because they are likely contaminants of a spaceship and previously known to have extremophile capabilities.

There are 10,000 species that live on a human in many different genera

So that is one new thing, the surprising length of time that micro-organisms can survive in dormant states on the Mars surface. Everyone used to think just a short time like minutes. But for months. And it might well be years, it is just that the experiment only ran for months on the ISS before they brought it back for analysis on Earth.

Then there are all the possible locations on or near the surface where life might survive. Near the equator less likely but even there there is the fairly recent surprising discovery of probable sub surface ice deposits in equatorial regions - which may be geologically ancient and gradually sublime and recondense on their way up to the surface and could provide habitats for life even near the equator.

And - there is a surprising diversity of micro-organisms on a human being. The human biome project is attempting to catalogue them all.

" Many of these organisms have not been successfully cultured, identified, or otherwise characterized. Organisms expected to be found in the human microbiome, however, may generally be categorized as bacteria (the majority), members of domain Archaea, yeasts, and single-celled eukaryotes as well as various helminth parasites and viruses, the latter including viruses that infect the cellular microbiome organisms (e.g., bacteriophages, the viruses of bacteria)."

http://en.wikipedia.org/wiki/Human_Microbiome_Project

It is a big project. Same as with the clean room analyses. Most of the micro-organisms in the human microbiome simply aren't known or described yet.

So you don't know what you are bringing to Mars. You know that some of the organisms can survive for months in dormant state on the surface. You don't know for sure but suspect that there are habitats on or near the surface that they can colonize.

I think it would be hard for someone to argue convincingly that humans can visit the Mars surface in a biologically reversible way today, as they used to a few years back. Because those spores are going to be spread in the wind and at least spread over many kilometers around the landing site, and won't be sterilized and many will still be viable months or years later. You can't reverse something like that.

And a human mission to the surface also needs to be safe from contaminating the planet in the case of a hard landing leading to death of the crew. That makes it even harder to argue for its safety from contamination point of view.

So, send humans to the surface and you contaminate it in a biologically irreversible way. I think that is pretty much certain, maybe a few would try to argue the other way but I think the opposite case would be hard to maintain using the most recent evidence from Mars and the most recent published research.

Offline robertinventor

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The backwards contamination issue is off topic here I think. So given the (rather sensible actually) policy of keeping threads on topic, I will post it as a new discussion thread. There is a lot that can be said on that topic!

Offline robertinventor

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When they do things like accuse others of being an eco-extremist

I am sure eco-extremists don't think that they are extreme :) What's wrong with this nice idea of living in caves in peace and harmony with nature? ;)

I admit that I was wrong here: you indeed have a bit extreme views, but so far they weren't about ecology - they were about science. You think that gaining knowledge about past life on Mars trumps just about anything else, that losing some bits of it is a gigantic loss. You are scientist-extremist :)

Okay thanks for the apology. That's okay I don't mind being called a scientist-extremist meaning someone who puts a high value on scientific knowledge and understanding :).

Offline mrmandias

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Looks like few appreciate the extraordinary value and uniqueness of a colonized Mars.

Throwing away political correctness, I'd classify people who want to ban Mars colonization as eco-nazis.

Hear, hear.

The universe has an endless supply of 'biologically pristine' material.

Offline Warren Platts

if there are any Mars organisms, most likely they are in deep, underground aquifers. Meanwhile, humans will be occupying the surface in self-contained, sealed habitats. Instituting some sort of decontamination procedure, like spraying down your spacesuit before you step outside would be easily doable. And if a bit of E. coli managed to get outside anyhow, it wouldn't last long in due to the UV radiation and perchlorates.

That is what everyone thought about five years ago. Not any more though.

The thing is that dormant states of micro-organisms have been shown capable of surviving for MONTHS on Mars surface in full sunlight.

Who says this? You're long on unnamed sources and very short on links. If you're going to be writing articles for Wikipedia, you're supposed to cite legitimate sources.

Quote
Near the equator less likely but even there there is the fairly recent surprising discovery of probable sub surface ice deposits in equatorial regions - which may be geologically ancient and gradually sublime and recondense on their way up to the surface and could provide habitats for life even near the equator.

[citation needed]

Quote
I think it would be hard for someone to argue convincingly that humans can visit the Mars surface in a biologically reversible way today, as they used to a few years back. Because those spores are going to be spread in the wind and at least spread over many kilometers around the landing site, and won't be sterilized and many will still be viable months or years later. You can't reverse something like that.

Months or years <> billions of years. Also, dormant spores <> active, reproducing life.

Like I said, the horses have already left the barn. You're trying to prevent something that's already happened...

Quote
most recent evidence from Mars and the most recent published research.

You haven't cited any. Your argument so far is mere appeal to authority--and you won't even say who the authority is! I am quite sure you are misunderstanding something.
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline Lar

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I am in process of getting together an article on contamination issues for Mars sample return for wikipedia. It just pulls together and paraphrases or summarizes some of the things that have been published on this, including publication on the legal aspects of it, break down of the risks of the proposed mission, and so on.

Ican post it for comment if anyone is interested in a separate thread


Post a link to it when you've got it in rough shape... heck, even if it's just a subpage of your user space and not yet in article space. I'll take a look.



Looks like few appreciate the extraordinary value and uniqueness of a colonized Mars.

Throwing away political correctness, I'd classify people who want to ban Mars colonization as eco-nazis.

I don't think we need to be invoking Godwin's Law. (http://en.wikipedia.org/wiki/Godwin%27s_law ) ... although I was tempted
« Last Edit: 05/16/2013 09:41 PM by Lar »
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline Jim

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As I said in my initial post, you are an eco-extremist. You are going to buzz here repeating your POV ad nauseum, impervious to any arguments to the contrary.

Pot meet kettle

Offline robertinventor

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> The thing is that dormant states of micro-organisms have been shown capable of surviving for MONTHS on Mars surface in full sunlight.

Who says this? You're long on unnamed sources and very short on links. If you're going to be writing articles for Wikipedia, you're supposed to cite legitimate sources.

-I've got sources for all those things. Just that in discussion like this you post links for most things, but tend not to post for every single thing you say. But yes reasonable to ask for them and you might find them interesting.

This is one of the references on longevity of micro-organisms exposed to the Mars environment

http://online.liebertpub.com/doi/abs/10.1089/ast.2011.0737?journalCode=ast

There have been quite a few papers on it now, and several experiments.

You can find lots of references for the many different locations on Mars where it is now thought that liquid water may be possible here, including those sub surface equatorial ice sheets here

http://en.wikipedia.org/wiki/Water_on_Mars#Possibility_of_Mars_having_enough_water_to_support_life

For the longevity the thing is that especially in thin films a high proportion were still viable under months and the researchers themselves in one of the papers I read said that in their opinion it meant that they were viable for years just that they hadn't done a long enough experiment to prove it and they planned a follow up experiment.

The difference between an unmanned mission and a manned mission is that with the rovers there is at least a chance, many think a reasonable chance, that the contamination is still just on the spacecraft or immediate vicinity. You are not talking about trillions of micro-organisms there, just thousands most likely.

Also human missions would bring micro-organisms that could never make the transition on the exterior of a spaceship combined with the cleaning in the clean rooms etc.

It is like the difference between dumping one animal, and an entire zoo + biological garden on Mars.
« Last Edit: 05/16/2013 10:17 PM by robertinventor »

Offline robertinventor

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Post a link to it when you've got it in rough shape... heck, even if it's just a subpage of your user space and not yet in article space. I'll take a look.

Great, will do. Actually it is in my sandbox at present. I'm a bit caught up with other stuff actually, so especially as this is such an active forum and I might get like a dozen replies in a few hours after I post, and would be nice to just have a look at it first, and got work to do too, so maybe tomorrow evening?

Offline robertinventor

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The universe has an endless supply of 'biologically pristine' material.

That is probably true, we don't know for sure, but probably.

The only thing is, most of it is light years away from us. Apart from oceans beneath icy surfaces of the Moons, but there is no way at present to know if life actually does evolve there, or if it is similar to Earth life or if Mars life is interestingly different from either, or if there are deposits there for us to examine as there are on Mars to find out about the past evolution and how accessible they are.

But the nearest early Earth analogue apart from Mars, and Venus which is not much use for study of origins of life, well we don't even know if it exists, just seems very likely. If it does, is at least light years away, not going to even send a robotic probe to it within any of our lifetimes, at least highly unlikely.

That's why. Probably on a cosmic scale it is not so unique (though how do we now for sure but probably). But on human scale, in terms of its impact for humanity and for our science, it is unique in its similarity to Earth, there is only the one Mars as an early Earth analogue. We are very lucky to have it. And we don't know what is there yet.
« Last Edit: 05/16/2013 10:27 PM by robertinventor »

Offline Lar

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Post a link to it when you've got it in rough shape... heck, even if it's just a subpage of your user space and not yet in article space. I'll take a look.

Great, will do. Actually it is in my sandbox at present. I'm a bit caught up with other stuff actually, so especially as this is such an active forum and I might get like a dozen replies in a few hours after I post, and would be nice to just have a look at it first, and got work to do too, so maybe tomorrow evening?

Sure, or you can send me a message on wiki. My userid there is... (wait for it.... ) "Lar"  :)

http://en.wikipedia.org/wiki/User:Lar
« Last Edit: 05/16/2013 10:37 PM by Lar »
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline Warren Platts

-I've got sources for all those things. This is one of the references on longevity of micro-organisms exposed to the Mars environment

http://online.liebertpub.com/doi/abs/10.1089/ast.2011.0737?journalCode=ast

Gee thanks... A link to a paper with a $51 pay wall. Oh brother....

For those who don't have $51 to waste, here is the link to a free version...........................................


http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3371261/
« Last Edit: 05/17/2013 02:17 AM by Warren Platts »
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline go4mars

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A lot of smart people seem to think that mars is our best hope to establish a self-sustaining colony off earth and that creating self-sustaining colonies in free space is basically impossible with current technology, while establishing a colony on mars is just barely possible with current or near-term technology.

Prove them wrong by establishing a self-sustaining O'Neill-style colony, and you would have an argument for keeping mars pristine. But as long as mars is the only borderline habitable place in the solar system other than earth, making the life we know to exist on earth multiplanetary is much more important than preserving some hypothetical indigenous mars life.
Agreed. 
And to expand, it isn't just about humanity in my mind.  Backing up all kinds of ecological elements on Mars, ASAP, as human population on Earth continues to expand, is more compelling than fretting over germs and endoliths, which btw can potentially have sealed preservations or research zoos on Mars anyway.      Plus, tortoises would be downright jumpy there.  Let's liberate them to a more appropriate gravity field.  ;).   

I'm actually strongly in favour of Pleistocene rewilding, partially for similar reasons and recognize that would be a good solution for the above argument I placed.  But only on a regional scale, and complex relationships with stakeholders (populous humanity) makes wide implementation extremely challenged on Earth. 
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline robertinventor

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-I've got sources for all those things. This is one of the references on longevity of micro-organisms exposed to the Mars environment

http://online.liebertpub.com/doi/abs/10.1089/ast.2011.0737?journalCode=ast

Gee thanks... A link to a paper with a $51 pay wall. Oh brother....

For those who don't have $51 to waste, here is the link to a free version...........................................


http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3371261/

Sorry, my mistake. I read a free version of it, must have given the wrong link.

Offline robertinventor

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Prove them wrong by establishing a self-sustaining O'Neill-style colony, and you would have an argument for keeping mars pristine. But as long as mars is the only borderline habitable place in the solar system other than earth, making the life we know to exist on earth multiplanetary is much more important than preserving some hypothetical indigenous mars life.
Agreed. 

And to expand, it isn't just about humanity in my mind.  Backing up all kinds of ecological elements on Mars, ASAP, as human population on Earth continues to expand, is more compelling than fretting over germs and endoliths, which btw can potentially have sealed preservations or research zoos on Mars anyway.      Plus, tortoises would be downright jumpy there.  Let's liberate them to a more appropriate gravity field.  ;).   

I'm actually strongly in favour of Pleistocene rewilding, partially for similar reasons and recognize that would be a good solution for the above argument I placed.  But only on a regional scale, and complex relationships with stakeholders (populous humanity) makes wide implementation extremely challenged on Earth. 
[/quote]

Okay - for me actually one motivation for space colonies just as for you is as a place for preservation of wildlife from Earth indeed :).

Anyway, no way that Mars is going to have a climate suitable for tortoises on the surface in near future. The Mars trilogy time scale is massively speeded up for dramatic effect.  On Mars as in space it would need to be in self contained habitats, paraterraforming, in the next few centuries anyway (longer term, controversial whether or not an Earth normal type atmosphere on Mars is an achievable goal).

So - main thing is to establish that you can get those self contained ecosystems working, as in e.g. follow up to the biosphere project, and then something like that in space.

That's best done close to Earth and in a space habitat, or could be on the Moon. Far cheaper, easier to monitor etc. And long term just as for humans, you have space for hundreds of times the land area in space as on any of the planets.

For tortoises, small animals then you don't need big habitats, just need them to be self contained as far as possible. Also can have them supplied with oxygen from water to start with no need to be totally self contained if the main aim is conservation. And - well until you have truly large numbers and areas for habitats in space it is going to be a lot easier to just keep them in zoos on the Earth.

But when it is as easy to fly into space as it currently is to fly to another country - and at that stage space colonies may be commonplace, then yes I can well see that happening.

For me, then large space habitats are no more futuristic than large habitats on Mars. Both involve big unknowns. Both have carefully thought out feasibility studies that suggest they are possible by enthusiastic advocates of their concepts. I don't think you can single out one of them and say it is more likely to succeed than the other one from the practical or engineering point of view.

« Last Edit: 05/17/2013 08:43 AM by robertinventor »

Offline Warren Platts

if there are any Mars organisms, most likely they are in deep, underground aquifers. Meanwhile, humans will be occupying the surface in self-contained, sealed habitats. Instituting some sort of decontamination procedure, like spraying down your spacesuit before you step outside would be easily doable. And if a bit of E. coli managed to get outside anyhow, it wouldn't last long in due to the UV radiation and perchlorates.

That is what everyone thought about five years ago. Not any more though.

The thing is that dormant states of micro-organisms have been shown capable of surviving for MONTHS on Mars surface in full sunlight. ...

... most recent evidence from Mars and the most recent published research.

Just as I thought: you are misunderstanding the literature you are quoting. The paper you cite states that UV radiation is in fact highly lethal to bacterial spores.

Quote from: Horneck et al.
The results were much more dramatic for the Sun-exposed spores during the ‘‘trip to Mars.’’ Only in some samples were a few survivors detected from monolayers of B. pumilus, which decreased the survival rate to less than 10 -6. These few survivors may be considered ‘‘lucky winners’’ that may have been located in pits or cracks of the aluminum surface and were thereby either shadowed or covered by upper, killed spores (Schuerger et al., 2005; Vaishampayan et al., 2012) that protected them from full UV radiation. This high lethality of unfiltered extraterrestrial solar UV radiation has already been demonstrated in previous short-term spaceflight studies, for example, on board Spacelab 1 (Horneck et al., 1984) and the ESA Biopan missions (Horneck et al., 2001). Ten seconds of exposure to unfiltered solar radiation in space killed 99% of spores of B. subtilis. Furthermore, space vacuum and solar UV radiation acted synergistically in spore inactivation.

Even the protected spores had a 50% mortality or greater. Meaning the half-life of protected spores is on the order of a year or less. In other words, there is little risk of "surface contamination".
« Last Edit: 05/17/2013 02:48 PM by Warren Platts »
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline robertinventor

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I suppose it is one of those things where different features of the paper spring out at you depending on your point of view.

For instance even exposed to full sunlight, less than one in a million spores can last a month in monolayers. But that means that out of a trillion spores, less than a thousand would be left after months. Far more than what used to be thought, that they would all die within seconds or at most minutes of exposure to the sunlight.

During those months it just needs some of those spores to get into a crack in a grain of sand or a shadow, and they then have 70-75% chance of surviving for 1.5 years.

That then would give. according to my calculations just under a 3% chance of surviving for 15 years on the surface, e.g. in a crack in a dust grain carried in the wind, and assuming the probability of mortality is uniform for the dormant spores (given that spores are amazingly durable in absence of radiation that seems a reasonable way to get a first estimate). (using 0.7^10 = 0.0282475249)

I summarized it badly, I agree, sorry about that and you are right to say that it was misleading.

But the conclusions still hold. And it was not intentionally misleading. I haven't said anything intentionally misleading in this forum.
« Last Edit: 05/17/2013 01:47 PM by robertinventor »

Offline robertinventor

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Sure, or you can send me a message on wiki. My userid there is... (wait for it.... ) "Lar"  :)

http://en.wikipedia.org/wiki/User:Lar
Will do. Thanks!

Offline Warren Platts

I suppose it is one of those things where different features of the paper spring out at you depending on your point of view.

For instance even exposed to full sunlight, less than one in a million spores can last a month in monolayers. But that means that out of a trillion spores, less than a thousand would be left after months. Far more than what used to be thought, that they would all die within seconds or at most minutes of exposure to the sunlight.

During those months it just needs some of those spores to get into a crack in a grain of sand or a shadow, and they then have 70-75% chance of surviving for 1.5 years.

That then would give. according to my calculations just under a 3% chance of surviving for 15 years on the surface, e.g. in a crack in a dust grain carried in the wind, and assuming the probability of mortality is uniform for the dormant spores (given that spores are amazingly durable in absence of radiation that seems a reasonable way to get a first estimate). (using 0.7^10 = 0.0282475249)

I summarized it badly, I agree, sorry about that and you are right to say that it was misleading.

But the conclusions still hold. And it was not intentionally misleading. I haven't said anything intentionally misleading in this forum.

The conclusions do not hold. You're also forgetting that LEO is not the same as interplanetary space. Ever heard of GCRs? Also the simulated Mars environment was lame: e.g., no perchlorates. It almost certainly vastly overestimates the survival rate of your hypothetical dust grain.

Even using your own figures, every single spore out of the trillion would be dead within 70 years. Therefore your claim that Mars would be "irreversibly" contaminated with a "high probability" is demonstrably false--using your own logic!!!

And even supposing you are right, then it's too late already! Mars is already irreversibly contaminated, so preventing further exploration isn't going to solve anything.

Either way, you have no case.

But watch: you will not change your mind. Of that I am quite certain! ;D
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline robertinventor

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Just a bit of clarification. The hope is that the current mars missions that crashed on the surface reversibly contaminated the surface. There is no question at all that it is contaminated by them.

The thing is the spores are just on the surface of the spacecraft, and there is a good chance they have remained there and are just sitting there dormant, and that by removing the spacecraft and any surrounding debris you can reverse the contamination.

With a human landing though you have the spores blown out of the airlock and landing on the surface, brushed off the astronauts spacesuits while they are working, etc etc. And the numbers are far far larger, a million spores to every single spore on an unmanned spacecraft.

Also only a few species can survive the rigour of the journey to Mars on an unmanned spacecraft, which is harder than surviving when you get there. And many will be removed with the sterilizing methods.

Then also I have argued that if Mars is already contaminated with one or several species from the crashed spacecraft, that is not at all an argument in favour of introducing more contamination to the planet. That's like arguing that because there are rabbits in Australia then we should introduce all the European animals, plants, fungi etc. to Australia.

Instead, it would be a strong signal that we should stop and take stock of the situation. I think the reaction of COSPAR assembly of scientists to a detected contamination of Mars by life would be to recommend more stringent regulations in the future, not relax them all completely.  We would need to learn form what happened, observe the effect of the contamination on Mars, and decide what the next move should be.

I agree the study is not perfect. But it is only one of numerous recent studies that attempt replication of Mars conditions both in labs on the Earth and in space experiments.

Here is another one from 2012 which does use perchlorates:

http://www.lpi.usra.edu/meetings/lpsc2012/pdf/1507.pdf

There are dozens of them though. And normally each one only tests a couple of micro-organisms of the many that could be tested.
« Last Edit: 05/17/2013 03:56 PM by robertinventor »

Offline Vultur

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A general point: endospore/cryptobiosis survival is irrelevant if there are no habitats accessible from the Martian surface where the lifeform can actually metabolize/grow/reproduce.

I don't believe anything we are likely to do on Mars in this century would affect deep endoliths.


I severely doubt we will find early life on Mars. If there is life there, it will be specialized life highly adapted to the current harsh conditions on Mars, no closer to abiogenesis than modern Earth microbes.

Finding life on Mars would be hugely scientifically valuable... but not because of abiogenesis.
Did you follow my reasoning for it? That in the first few hundred million years after formation, Mars was a near twin to Earth.

But it isn't now.

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That it had organics from the comets just like Earth.

Just like everything else. If that's your criterion, Mars isn't any better than any random rock -- worse, since its chemical environment (perchlorates etc.) is harsher.


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If there was no life evolved in early Mars then that is a big puzzle too. If it doesn't even produce protobionts and rich amounts of amino acids then there is a lot of explaining to be done.

It's a big puzzle either way. Those experiments don't necessarily correlate to what actually happened on early Earth. I incline toward the idea that abiogenesis, origin of Earth life, is an unanswerable question since the evidence hasn't survived 4 billion years, and no other planet necessarily followed the same path as earth (probably didn't).

If we found some planet, Mars or otherwise, with new life - say ten million years from abiogenesis - we might be able to answer the question for that planet. But still not for Earth. And if life originated on Mars it'd be billions of years ago, when it was more habitable.

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That the atmosphere is in equilibrium suggests that these habitats don't support much life, the ones with contact with the surface atmosphere at least. But they might just be very sparsely populated with life, because the total volume of the habitat is low, as it is in some of these examples. The deeper habitats may have abundant life for all we know. The deeper habitats may get exposed to the surface as result of meteoritic impact on Mars, but some may be kms deep and hard to access.

Therefore the deeper habitats will be unaffected by human activity on the surface.

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Also all the continents were merged in a super continent 80 million years or so ago. Most life on Mars if it exists has probably evolved independently from Earth for at least billions of years, even if some extremophile species was transferred more recently like a few tens of million years ago.

We have nowhere on Earth to compare with Mars as an analogue for its level of isolation from the rest of microbial life on Earth.

Right, but isolation makes pathogenicity LESS likely, not more.


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There are indeed microbes on Earth such as radiodurans that are awesome as you describe. But though they are found in a huge range of environments, the populations tend to be sparse.

Right, sparse, therefore they're not going to take over the Earth.

They are sparse because the tradeoff for being adapted to tons of environments is that you are poorly adapted to them compared to a specialist.



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There is a lot of water.

Compared to Mercury or the Moon, but not compared to Earth.


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Methane is a greenhouse gas so once it starts to form it could start to warm up the planet in a runaway greenhouse effect.

...which would be beneficial for human colonization.

Methane is too unstable for you to get a mostly methane atmosphere or whatever, AFAIK. I mean, if you had oceans filled with methanogens like oxygen-producing life on Earth, yeah, maybe. But Mars isn't rich/habitable enough.

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> Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.
Yes. The thing is though, those diseases are dangerous to humans. For instance the way that remote uncontacted tribes in the Amazon die due to things that are trivial for us like flu.

Not the same thing at all. Those are disease already adapted to humans, introduced to a new human population.

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And remote chance that it is so different that no humans have any natural immunity to it, yet still able to infect us, that's the possibility that could lead to extinction of humans. Very very low chance most would say. The backward infection possibility everyone is in agreement is pretty unlikely. But not zero. As Carl Sagan said, should you take even a tiny chance like that with a billion lives? The precautionary principle says no. You need to show it can't happen beyond any reasonable doubt.

It IS beyond any reasonable doubt. Extinction plagues, for a widespread numerous species like humans, are sensationalism or bad science fiction, not science. 
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The difference is that we have generated immunity to those.

No, we don't, not at the beginning, or they wouldn't cause plagues!

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Basically you can argue two ways here, as Carl Sagan said in his quote. You can argue that there is a low chance that the life on Mars can infect us because it is so isolated from Earth and different.

Not just low. Low enough to be indistinguishable from zero for all practical purposes.

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But you can also argue that it is more dangerous because we lack natural immunity to whatever is there.

You could argue that, but you'd be wrong. Pathogenicity is an adaptation, it's not the default for microbes.

Anyway, Sagan was not a biologist.
« Last Edit: 05/18/2013 09:51 PM by Vultur »

Offline robertinventor

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A general point: endospore/cryptobiosis survival is irrelevant if there are no habitats accessible from the Martian surface where the lifeform can actually metabolize/grow/reproduce.

I don't believe anything we are likely to do on Mars in this century would affect deep endoliths.

What about comet or meteorite impacts on Mars mixing surface and deep habitats? Also caves that give access to them?

I severely doubt we will find early life on Mars. If there is life there, it will be specialized life highly adapted to the current harsh conditions on Mars, no closer to abiogenesis than modern Earth microbes.

Finding life on Mars would be hugely scientifically valuable... but not because of abiogenesis.

Oh of course. Or at least probable.

If it went through some of the early stages of life such as the RNA world or the metabolism first world, I suppose theoretically they could still be there, and e.g. be activated again when the ice caps melt after a comet impact on the poles of Mars - leads to temporary lakes for a thousand years or so covered in an insulating layer of ice is one idea.

Or might still be doing their thing deep underground.

So not impossible.

But I think they require an organics rich environment and not likely to still occur in the hostile surface environment.

The interest for abiogenesis is that Mars is not all perchlorates that destroy all organics. There are clays, and sulfates, that are good for preserving organics. Curiosity landed near Mount Sharp for just that reason, because clays and sulfates were detected their from orbit.

Opportunity has recently completed a long journey it made to reach a similar spot on the surface detected from orbit.
http://www.spaceflightnow.com/news/n1301/25opportunity/

Like Earth there are many different rock types and "soil" types on Mars.


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> That it had organics from the comets just like Earth.

Just like everything else. If that's your criterion, Mars isn't any better than any random rock -- worse, since its chemical environment (perchlorates etc.) is harsher.

It is of course the combination of the organics with the evidence, incontrovertible now, of extensive flooding. And the scientists are moving towards a consensus that there were probably early seas on Mars as well during the Noachian period.

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> If there was no life evolved in early Mars then that is a big puzzle too. If it doesn't even produce protobionts and rich amounts of amino acids then there is a lot of explaining to be done.

It's a big puzzle either way. Those experiments don't necessarily correlate to what actually happened on early Earth. I incline toward the idea that abiogenesis, origin of Earth life, is an unanswerable question since the evidence hasn't survived 4 billion years, and no other planet necessarily followed the same path as earth (probably didn't).

If we found some planet, Mars or otherwise, with new life - say ten million years from abiogenesis - we might be able to answer the question for that planet. But still not for Earth. And if life originated on Mars it'd be billions of years ago, when it was more habitable.

Yes it would be. The thing is that you have the chance on Mars of actually having evidence from those times billions of years ago, because it was a near twin to Earth then, and because it hasn't had any continental drift, and has kilometers deep sediments from those times that have just built up and up without any disturbance or metamorphosing as happens on Earth. The whole of Mount Sharp is believed to consist of layers of sediment from the early Mars.

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> That the atmosphere is in equilibrium suggests that these habitats don't support much life, the ones with contact with the surface atmosphere at least. But they might just be very sparsely populated with life, because the total volume of the habitat is low, as it is in some of these examples. The deeper habitats may have abundant life for all we know. The deeper habitats may get exposed to the surface as result of meteoritic impact on Mars, but some may be kms deep and hard to access.

Therefore the deeper habitats will be unaffected by human activity on the surface.
Probably, not immediately anyway. Though if there is some communication with the surface, then any signals from them e.g. the methane, will be confused by signals from introduced life. And if the samples are removed to study them, if you dig into those deposits to try to study them you have contamination issues then.

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> We have nowhere on Earth to compare with Mars as an analogue for its level of isolation from the rest of microbial life on Earth.

Right, but isolation makes pathogenicity LESS likely, not more.

That is where the jury is out. You can argue that it makes it less likely. You can also argue that it means that we have not developed any defences to it.

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> There are indeed microbes on Earth such as radiodurans that are awesome as you describe. But though they are found in a huge range of environments, the populations tend to be sparse.

Right, sparse, therefore they're not going to take over the Earth.

They are sparse because the tradeoff for being adapted to tons of environments is that you are poorly adapted to them compared to a specialist.
Yes probably, makes sense. But don't need to take over the Earth to be a major nuisance or even cause extinctions.

E.g. allergens, interfere with crop growing, are able to grow on human skin (in small numbers right but in a way that is harmful to humans) or causes problems when breathed in, athsma or whatever.

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> Methane is a greenhouse gas so once it starts to form it could start to warm up the planet in a runaway greenhouse effect.

...which would be beneficial for human colonization.

Methane is too unstable for you to get a mostly methane atmosphere or whatever, AFAIK. I mean, if you had oceans filled with methanogens like oxygen-producing life on Earth, yeah, maybe. But Mars isn't rich/habitable enough.

There I just don't know the answer.  It was just something to think about. If not methanogens, maybe something else that creates gases that are toxic to humans, maybe in small doses even, maybe more toxic than methane, just some organic biproduct of their growth that happens to be toxic for us and also happens to be a gas rather than liquid.

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> Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.

But would it? Nothing like that has ever happened on Earth. It is a slower process. Here we have a whole planet to evolve in. And the micro-organisms are from the human microbiome to start with.

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> Yes. The thing is though, those diseases are dangerous to humans. For instance the way that remote uncontacted tribes in the Amazon die due to things that are trivial for us like flu.

Not the same thing at all. Those are disease already adapted to humans, introduced to a new human population.
Just an analogy, not perfect in all respects.
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> And remote chance that it is so different that no humans have any natural immunity to it, yet still able to infect us, that's the possibility that could lead to extinction of humans. Very very low chance most would say. The backward infection possibility everyone is in agreement is pretty unlikely. But not zero. As Carl Sagan said, should you take even a tiny chance like that with a billion lives? The precautionary principle says no. You need to show it can't happen beyond any reasonable doubt.

It IS beyond any reasonable doubt. Extinction plagues, for a widespread numerous species like humans, are sensationalism or bad science fiction, not science. 

It is reasonable enough so that the National Reseach Council lists it as a possible threat. I am researching this for my wikipedia article on MSR, and so have bought the book from the National Research Council on the topic and am currently reading it.

This is what they write:

"Thus, a key question posed to the committe is whether a putative martian organism or organisms, inadvertently released from containment, could produce large-scale negative pathogenic effects in humans or have a destructive impact on Earth's ecological system or environments."

They then divide it into three categories:

"
* Large-scale negatie pathogenic effects in humans;

* Destructive impacts on Earth's ecological systems or environments; and

* Toxic and other reffects attributable to microbes, their cellular structures, or extracellular products.
"

They conclude that the last one is unlikely - that's the "martian microbes taking over the world scenario" you mentioned.

But the other two

"The committee found that the potential for large-scale negative effects on Earth's inhabitants or environment by a returned martian life form appears to be low, but is not demonstrably zero."

On the meteorite impacts they say

"Despite suggestions to the contrary, it is simply not possible, on the basis of current knowledge, to determine whether viable martian life forms have already been delivered to the Earth. Certainly in the modern era there is no evidence for large-scale or other negative effects that are attributable to the frequent deliveries to Earth of essentially unaltered martian rocks. However the possibility that such effects occurred in the distant past cannot be discounted. Thus it is not appropriate to argue that the existence of martian microbes on Earth negates the need to treat as potentially hazardous any samples returned from Mars via robotic spacecraft".

That's from the !Assessment of Planetary Protection Requirements for Mars Sample Return Missions, National Research Council, 2009, chapter 5, "The Potential for Large-Scale Effects".

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> But you can also argue that it is more dangerous because we lack natural immunity to whatever is there.

You could argue that, but you'd be wrong. Pathogenicity is an adaptation, it's not the default for microbes.

Anyway, Sagan was not a biologist.

Actually, though trained as a physicist, for his work at postgraduate level he wrote his thesis on the origins of life, and for his postdoctoral work he worked with geneticists

http://en.wikipedia.org/wiki/Carl_Sagan#Education_and_scientific_career
« Last Edit: 05/18/2013 11:36 PM by robertinventor »

Offline gospacex

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Okay thanks for the apology. That's okay I don't mind being called a scientist-extremist meaning someone who puts a high value on scientific knowledge and understanding :).

Do you understand that it is an extremist position?

Most people don't think that science is the most important thing for humanity to do. It is a _tool_ (very valuable one, but still just a tool), not _the goal_.

Offline robertinventor

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> Okay thanks for the apology. That's okay I don't mind being called a scientist-extremist meaning someone who puts a high value on scientific knowledge and understanding :).

Do you understand that it is an extremist position?

Most people don't think that science is the most important thing for humanity to do. It is a _tool_ (very valuable one, but still just a tool), not _the goal_.

Depends what you mean. Minority yes, to have a really high value for science. Shared by nearly all scientists and mathematicians, the ones that do research into pure science at least, research scientists. Which in population as a whole is a tiny minority of the population, totally agree.

But didn't say "the most important thing" just highly value it. Other things I also highly value such as composing, and artists, many things.

Similarly enthusiasm and high value on space colonization is one that is shared by only a minority, very few have that view too. So if you call me a science extremist, you should call yourself a space colonization extremist and specifically a Mars colonization extremist :).

Which is okay :). Diversity in ideas and views is great. It is only when people start to think that their own POV is the only possible POV that it gets nasty.



« Last Edit: 05/19/2013 01:40 AM by robertinventor »

Offline Vultur

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A general point: endospore/cryptobiosis survival is irrelevant if there are no habitats accessible from the Martian surface where the lifeform can actually metabolize/grow/reproduce.

I don't believe anything we are likely to do on Mars in this century would affect deep endoliths.

What about comet or meteorite impacts on Mars mixing surface and deep habitats?

Impacts that big are rare. Really, really rare.

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Also caves that give access to them?

Are there cave systems that deep on Mars?
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The interest for abiogenesis is that Mars is not all perchlorates that destroy all organics. There are clays, and sulfates, that are good for preserving organics. Curiosity landed near Mount Sharp for just that reason, because clays and sulfates were detected their from orbit.

I severely doubt an RNA world or metabolism-first world would leave distinguishable fossil evidence, even on Mars.


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It is of course the combination of the organics with the evidence, incontrovertible now, of extensive flooding. And the scientists are moving towards a consensus that there were probably early seas on Mars as well during the Noachian period.

Yeah. But if life did originate on Mars, there will not be evidence of how abiogenesis occurred, since the life would outcompete the proto-life and use up the organics. Just like on Earth.

If life did not originate on Mars, there will not be evidence of how abiogenesis occurred, since it didn't occur.

I seriously believe the only way we could ever get an actual answer on abiogenesis is to find and study a planet where life had originated very recently - a hundred million years at most. Possibly much less.

And Mars is highly unlikely to be that planet.

Check Titan; its colder temperature will make chemistry slower, so if there's life on Titan, it might have only gotten as far in X billion years as earth life did in X hundred million.

But of course, Titan life (if existing) would be chemically too different from Earth life for its abiogenesis process to be relevant. So still...


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Probably, not immediately anyway. Though if there is some communication with the surface, then any signals from them e.g. the methane, will be confused by signals from introduced life. And if the samples are removed to study them, if you dig into those deposits to try to study them you have contamination issues then.

Yeah, I was referring to deep endoliths. If the methane proves to be life caused, that's a different story. But we should have an answer on that before humans land on Mars: Curiosity (and maybe MAVEN) may provide some evidence, and ExoMars has a Trace Gas Orbiter specifically supposed to look for it.

I severely doubt humans on Mars before 2030. Mars One wants 2023, but no way will they do it by then.


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Right, but isolation makes pathogenicity LESS likely, not more.

That is where the jury is out. You can argue that it makes it less likely. You can also argue that it means that we have not developed any defences to it.

No, the jury is NOT out. Pathogenicity is an adaptation. An organism living in an environment with no complex life to parasitize will not evolve pathogenicity.

Even if, stacking implausibilities upon implausibilities, some Martian microbe managed to survive in the superheated superoxygenated super-biologically-hostile (by Martian standards) environment of a human (and I consider even this the next thing to impossible) it wouldn't be adapted to spread like an infectious disease.


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There I just don't know the answer.  It was just something to think about. If not methanogens, maybe something else that creates gases that are toxic to humans, maybe in small doses even, maybe more toxic than methane, just some organic biproduct of their growth that happens to be toxic for us and also happens to be a gas rather than liquid.

Thing is, though, we'd already have to totally recreate the Martian atmosphere and environment to make it human-breathable. Some introduced microbe spitting out cyanide wouldn't make that meaningfully harder; compared to the immense difficulty of terraforming, wiping out that microbe would be trivial.

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> Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.

Quote
But would it? Nothing like that has ever happened on Earth. It is a slower process. Here we have a whole planet to evolve in. And the micro-organisms are from the human microbiome to start with.

No, they are not, not usually. New diseases are often introduced from other organisms, primates or rats or livestock, occasionally birds.

A Martian organism would not have a chance to compete. It's the whole "evolutionary arms race" concept - it hasn't had any time to evolve ways to get around immune systems, since nothing on Mars is complex enough to have an immune system. Primates and rats and livestock and birds do.

Remember, pathogenicity is a specific evolutionary adaptation - not a default.

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It is reasonable enough so that the National Reseach Council lists it as a possible threat. I am researching this for my wikipedia article on MSR, and so have bought the book from the National Research Council on the topic and am currently reading it.

This is what they write:

"Thus, a key question posed to the committe is whether a putative martian organism or organisms, inadvertently released from containment, could produce large-scale negative pathogenic effects in humans or have a destructive impact on Earth's ecological system or environments."

They then divide it into three categories:

"
* Large-scale negatie pathogenic effects in humans;

* Destructive impacts on Earth's ecological systems or environments; and

* Toxic and other reffects attributable to microbes, their cellular structures, or extracellular products.
"

They conclude that the last one is unlikely - that's the "martian microbes taking over the world scenario" you mentioned.

Actually, I was including both the second and the third.


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On the meteorite impacts they say

"Despite suggestions to the contrary, it is simply not possible, on the basis of current knowledge, to determine whether viable martian life forms have already been delivered to the Earth. Certainly in the modern era there is no evidence for large-scale or other negative effects that are attributable to the frequent deliveries to Earth of essentially unaltered martian rocks. However the possibility that such effects occurred in the distant past cannot be discounted. Thus it is not appropriate to argue that the existence of martian microbes on Earth negates the need to treat as potentially hazardous any samples returned from Mars via robotic spacecraft".

My argument is not based on Mars microbes having come to Earth before.

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Actually, though trained as a physicist, for his work at postgraduate level he wrote his thesis on the origins of life, and for his postdoctoral work he worked with geneticists

http://en.wikipedia.org/wiki/Carl_Sagan#Education_and_scientific_career

Ah, OK. But given the time frame of that work (the 50s! DNA's structure was just then being discovered!), and how immensely much we've learned about biology and especially molecular & microbiology since then, I'm not sure how relevant it is.
« Last Edit: 05/19/2013 05:44 PM by Vultur »

Offline robertinventor

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> What about comet or meteorite impacts on Mars mixing surface and deep habitats?

Impacts that big are rare. Really, really rare.

I know, but do happen, the comet ISON has a remote chance of hitting Mars or did last time I read about it.

This is the news story about ISON hitting Mars on its way into the solar system.

http://www.space.com/20045-comet-hit-mars-2014.html

But they seem to have concluded it won't hit Mars now with current distance from Mars estimated 10,830,000 km;

http://en.wikipedia.org/wiki/C/2012_S1

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> Also caves that give access to them?

Are there cave systems that deep on Mars?
Nobody knows how deep the cave systems go, just that there are caves on Mars. The lava tube caves are almost certainly close to the surface. But the Volcano tectonic caves may go very deep

http://www.caves.org/pub/journal/PDF/V74/cave-74-01-33.pdf

BTW I also wonder if there might be caves in the kilometers deep deposits like Mount Sharp, if streams found their way down through the sediments as they do on Earth, a bit like our limestone caves though not through limestone obviously, dissolving soluble minerals on the way, and may have small cave entrances not easy to see from orbit. This last is just speculation on my part, don't know of any papers on it.,

Oh just found a quote about just that idea of caves formed by underground streams, in that ref:

". Accordingly, older caves, perhaps formed by aqueous processes, where life might have retreated underground as the Martian surface became increasingly inhospitable are more likely to contain evidence of past or extant life"

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> The interest for abiogenesis is that Mars is not all perchlorates that destroy all organics. There are clays, and sulfates, that are good for preserving organics. Curiosity landed near Mount Sharp for just that reason, because clays and sulfates were detected their from orbit.

I severely doubt an RNA world or metabolism-first world would leave distinguishable fossil evidence, even on Mars.
You have the nanobes for one thing, they could survive from a metabolism first world. Then since on Earth micro-organisms can remain viable after 250 million years - that is viable not just able to be analysed - then since similar deposits occur on Mars, it seems not too much of a stretch to suppose that the organic chemistry could be analysed to see if for instance RNA occurred in it even after billions of years, and given the extreme cold conditions on Mars, and given that the colder the material the longer organic remains are preserved.

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> It is of course the combination of the organics with the evidence, incontrovertible now, of extensive flooding. And the scientists are moving towards a consensus that there were probably early seas on Mars as well during the Noachian period

Yeah. But if life did originate on Mars, there will not be evidence of how abiogenesis occurred, since the life would outcompete the proto-life and use up the organics. Just like on Earth.
There I beg to differ. Because the organic deposits in the salt will be isolated from the life which will only occur in places with liquid water. So if the organic deposits remain at extremely low temperatures and are never warmed up enough for liquid water to occur, they should remain unchanged since they were formed.
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If life did not originate on Mars, there will not be evidence of how abiogenesis occurred, since it didn't occur.
Oh - there that's the most interesting case at all in my book. It gets nearly as far as life but not quite. So you get the early stages, maybe as far as metabolism first models or RNA world, but no life ever in the modern sense. We could learn a lot about abiogenesis that way. Also especially since various areas of Mars would be self contained, almost like different planets, you could see if the same process happened in all the seas and flooded areas, or if different pathways were followed in different places on Mars.

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> I seriously believe the only way we could ever get an actual answer on abiogenesis is to find and study a planet where life had originated very recently - a hundred million years at most. Possibly much less.

And Mars is highly unlikely to be that planet.


Actually Mars might be exactly that. It was warm like Earth for a few hundred million years at most, and then got plunged into a deep freeze, and deep enough below the surface exist pristine deposits, if they are in clay or sulfate deposits, that preserve organic matter unchanged from those times. It is almost as good as actually being able to go back in time to those times. At least that's what I hope will happen.

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> Check Titan; its colder temperature will make chemistry slower, so if there's life on Titan, it might have only gotten as far in X billion years as earth life did in X hundred million.

But of course, Titan life (if existing) would be chemically too different from Earth life for its abiogenesis process to be relevant. So still...
Agree Titan may have a very different life from Earth and it may be of great interest for abiogenesis.

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> Probably, not immediately anyway. Though if there is some communication with the surface, then any signals from them e.g. the methane, will be confused by signals from introduced life. And if the samples are removed to study them, if you dig into those deposits to try to study them you have contamination issues then.

Yeah, I was referring to deep endoliths. If the methane proves to be life caused, that's a different story. But we should have an answer on that before humans land on Mars: Curiosity (and maybe MAVEN) may provide some evidence, and ExoMars has a Trace Gas Orbiter specifically supposed to look for it.

I severely doubt humans on Mars before 2030. Mars One wants 2023, but no way will they do it by then.

2030 is too soon for me especially if there hasn't yet been an extensive study of the surface of Mars and at least tens of meters below the surface, and of ancient deposits from the formation of Mars, with in situ electron microscopes, DNA sequencers etc (all of which are now small enough to fly on spacecraft).

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No, the jury is NOT out. Pathogenicity is an adaptation. An organism living in an environment with no complex life to parasitize will not evolve pathogenicity.
Ah that is where the example of Legionnaires disease is relevant. It jumped straight to humans without going through any other intermediate animal host. Shows that an organism that does not evolve to parasitize humans can jump into an animal host in one go.

If you think about it, parasitizing has to start somewhere, every parasite of humans at some point wasn't a parasite of humans. Yes most come from other animal hosts, but like Legionnnaire's disease, at some point in the past were not parasites of any host at all.

In fact the adaptation to being a successful parasite is normally to do with adaptations to prevent it harming the host, because a parasite that kills its host will not last long and if it makes its host extinct then it makes itself extiinct too.

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Even if, stacking implausibilities upon implausibilities, some Martian microbe managed to survive in the superheated superoxygenated super-biologically-hostile (by Martian standards) environment of a human (and I consider even this the next thing to impossible) it wouldn't be adapted to spread like an infectious disease.

Depends. For instance simple example, if it lives in human lungs and causes humans to sneeze, that doesn't need any special adaptation.

Or like Legionnaire's disease it may spread in other habitats rather than in humans. Then it infects humans just because we breath it in. So not human to human, but rather spreads through environment and then from there to humans.

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Thing is, though, we'd already have to totally recreate the Martian atmosphere and environment to make it human-breathable. Some introduced microbe spitting out cyanide wouldn't make that meaningfully harder; compared to the immense difficulty of terraforming, wiping out that microbe would be trivial.
Wiping out a micro-organism over an entire planet is not trivial, in my view. Even for micro-organisms that are parasitic on humans, it is very hard. Imagine trying to wipe out a micro-organism that exists in the soil, world-wide distribution? I don't think it could be done, except maybe by finding something else that out competes it or parasitizes it - but then the cure could turn out worse than the thing you are trying to fix.

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> Or some organism evolves on Mars (rapid evolution and radiation of the introduced organisms) that humans are allergic to, or, since they are evolved from the human biome mainly, so they evolve some aggressive adaptation on the surface of Mars but are still adapted to live on humans as well, come back into the habitats as serious diseases when they left the habitats as benign even symbiotic organisms that help us.

Now, this could happen... but it would be no different from the new diseases that pop up all the time on Earth.

> But would it? Nothing like that has ever happened on Earth. It is a slower process. Here we have a whole planet to evolve in. And the micro-organisms are from the human microbiome to start with.

No, they are not, not usually. New diseases are often introduced from other organisms, primates or rats or livestock, occasionally birds.

Sorry this bit has got confused in the quote and requote. I was talking there about the case of human colonists introducing micro-organisms to Mars. They are mainly micro-organisms from the human microbiome because most of the micro-organisms in the spaceship will be. They then spread over the entire planet, and micro-evolve slightly in many ways. But because micro-organisms tend to preserve old adaptations, they remain adapted to humans as well, or with genetic code easily switched back on to let them re-adapt to humans.

When the humans return in their next visit, or the colonists who stay on Mars for years, then the micro-organisms readapt back to the habitat, and turn into something much more virulent as a result of adaptations they developed for the Mars surface. Because they all derived originally from the human micro-biome then I think that might be more likely to happen than if they were just a random group of micro-organisms from Earth or from other creatures not human.

That was the reasoning. It is a minor point, and I can't remember a published paper on it right now, will see if I have any notes of one or if it is just my own idea.

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A Martian organism would not have a chance to compete. It's the whole "evolutionary arms race" concept - it hasn't had any time to evolve ways to get around immune systems, since nothing on Mars is complex enough to have an immune system. Primates and rats and livestock and birds do.

Remember, pathogenicity is a specific evolutionary adaptation - not a default.



Yes but the adaptation is most often in the direction of becoming less toxic rather than more toxic. Because it is not in the interest of the pathogen to kill its host normally. Pathogens that have coexisted with higher organisms for a long time may even eventually become symbiotes and required for normal functioning of the organism.

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My argument is not based on Mars microbes having come to Earth before.

Okay. Sorry.

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> Actually, though trained as a physicist, for his work at postgraduate level he wrote his thesis on the origins of life, and for his postdoctoral work he worked with geneticists

http://en.wikipedia.org/wiki/Carl_Sagan#Education_and_scientific_career

Ah, OK. But given the time frame of that work (the 50s! DNA's structure was just then being discovered!), and how immensely much we've learned about biology and especially molecular & microbiology since then, I'm not sure how relevant it is.

Things have moved on for sure. But he is as relevant as anyone else from his time I think and was quite farseeing in many ways.
« Last Edit: 05/19/2013 07:31 PM by robertinventor »

Offline robertinventor

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Just discovered, there was a big conference on telerobotics last year organized by NASA. Interesting stuff! Overview here: http://telerobotics.gsfc.nasa.gov/papers/SymposiumReport-ExtendedVersion29Oct.pdf
and videos available here: http://telerobotics.gsfc.nasa.gov/index.cfm?event=General.agenda
News story here: http://www.spacenews.com/article/exploration-telerobotics-symposium#.UZnfPaIm3Sg



It helps give an idea of what telepresence exploration of Mars could be like, while keeping the surface pristine
« Last Edit: 05/21/2013 10:52 AM by robertinventor »

Offline alexterrell

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Having read through this thread, I'm not convinced of the need to preserve  a biologically pristine Mars.

- We don't really worry about destroying primitive life on Earth - I kill billlions of microbes if I take a course of anti-biotics. 
- As pointed out above, we have no qualms about eradicating small pox. We'd like to kill the malaria parasite as well.

I doubt there is life on Mars, but if there is, it may have come from Earth. That fact would in itself be of immense value to science, but the microbes themselves would not be much more valuable than those of Lake Vostok.

It would be different if the life forms evolved indpendently - complete with a different form of DNA. Then studying it would be of immense value, requiring in-situ crew. But life that evolved on Mars is unlikeley to be destroyed by Earth microbes, and unlike Earth derived life, can't be disguised. It would be easy to recognise. There is no chance that the Mars life could out-compete Earth life in an Earth like environment (like our habs and guts), and Earth life won't out compete Mars life in a cold vacuum.

Offline robertinventor

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Having read through this thread, I'm not convinced of the need to preserve  a biologically pristine Mars.

- We don't really worry about destroying primitive life on Earth - I kill billlions of microbes if I take a course of anti-biotics. 
- As pointed out above, we have no qualms about eradicating small pox. We'd like to kill the malaria parasite as well.
Okay first it is not about preserving individual microbes. It is not about preserving species that cause diseases either.
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I doubt there is life on Mars, but if there is, it may have come from Earth. That fact would in itself be of immense value to science, but the microbes themselves would not be much more valuable than those of Lake Vostok.

If it came from Earth it must be from an asteroid impact of 10 km or more. Probably from at least 10 million years ago.
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It would be different if the life forms evolved indpendently - complete with a different form of DNA. Then studying it would be of immense value, requiring in-situ crew. But life that evolved on Mars is unlikeley to be destroyed by Earth microbes, and unlike Earth derived life, can't be disguised. It would be easy to recognise. There is no chance that the Mars life could out-compete Earth life in an Earth like environment (like our habs and guts), and Earth life won't out compete Mars life in a cold vacuum.
Earth viruses could parasitise it directly. Earth microbes could out compete being better adapted just because of the greater amount of evolution that happened on Earth and because on Earth also there are extremophiles and polyextremophiles. Earth life could consume Mars life, as well, and lead to extinction especially if there is another Earth micro-organism able to take its place in the food chain. Mars life also could consist of single micro-organism ecosystems (known to exist on Earth), so very vulnerable to competition from Earth life, and slow growing, may be slower growing than Earth life.

Well adapted just means optimal. Mathematically, it can be a local maximum in the optimization process, and Earth life might have found another optimum that is better adapted, that often happens in evolution. Like when you climb a mountain if you keep going up until you can go no higher, it means you have reached the top of something, but it might not be the top of the entire mountain. If top of the mountain, might not be top of the mountain range. So life adaptation to a habitat can be like that, so it is reasonably likely given independent evolution that the Mars life is optimized in one way, Earth life in another. The Earth life might have found an optimum that lets it grow faster, or use nutrients that are present but not available to the Mars life, that lets it consume the Mars life, lets it colonize as a multi-species ecosystem to replace a single species ecosystem, etc, etc.

Life on Earth is not easily characterized because we only know something like 1% of species in most habitats, and we have DNA sequences of only a tiny number of the huge range of micro-organisms. It is even possible that there is a "shadow life" existing on Earth not based on DNA which we wouldn't notice because there is so much DNA based life going on to confuse the signals. That's Paul Davies' hypothesis. We could spot this "shadow life" if it exists on Mars more easily if there is no Earth life there to confuse the signals.

http://en.wikipedia.org/wiki/Shadow_life
http://en.wikipedia.org/wiki/Shadow_biosphere

So Earth life does confuse study, is not at all fully characterized, and could infect Mars, and out compete or infect Martian organisms. It could make it extinct, or it could just make it far harder to study.

And there are polyextremophiles such as the amazingly resistant Radiodurans that exist in our environment in clothing, soil, etc in small numbers, and other micro-organisms that have been tested for ability to withstand Mars conditions some of them are ordinary enough and are found in spacecraft clean rooms and will surely be on any human spaceship to Mars.

The human microbiome has estimated 10,000 species. But most of those are unknown, not characterized or sequenced, despite a massive project to try to characterize them, the human microbiome project and they are in many different genera including the archaea which are noted for many of them having extremophile capabilities.

What you say is the same as many people say, e.g. the FAQ on the Mars society site. But it is based on out of date science from about ten or twenty years ago, and the cutting edge science is not in agreement, and even ten or twenty years ago it was agreed in all the policy reviews that there is a remote but non zero chance that Mars life can be a biohazard and could cause mass extinctions on Earth, that possibility is thought very low probability but can't be ruled out completely. None of the policy reviews to date have been able to assign a probability of zero to that.
« Last Edit: 05/21/2013 10:42 AM by robertinventor »

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