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samkent
2008-Nov-20, 08:16 PM
Apparently quite a bit of water found.

http://www.space.com/scienceastronomy/081120-martian-glaciers.html

If we sent humans there, how long do think it would take us to use it up?

Iíll bet most of the systems on the drawing board involve 100% consumption of any water found. Now that we know itís there itís too easy to just dump our waste water overboard (sinks etc). If we break it down for the O2 we will just dump the H and excess CO2 overboard.

Look out Mars humans are coming to use up what you have!

PraedSt
2008-Nov-20, 08:46 PM
I wonder if this will materially affect the Mars-Moon debate. That's a huge amount of water they've found. ;)

Nicolas
2008-Nov-21, 08:00 AM
Things such as the water recycling plant introduced on the ISS may be useful here, to make sure the water is used as much as possible before it is "lost forever" in the sink.

Did I just say the ISS leads to developments? uh-oh, black choppers coming my way...

PraedSt
2008-Nov-21, 10:25 AM
Did I just say the ISS leads to developments? uh-oh, black choppers coming my way...
You're already in our sights. I wouldn't make any sudden moves if I were you. :)

samkent
2008-Nov-21, 12:55 PM
Ahhh but will they? It’s a lot more weight to land on the surface. It’s soooo much easier to just run some pipe 50 feet from the shelter and dump overboard. If it were just shower water all you would have after a day or so would be a miniscule amount of dirt and soap residue. As for the toilet, we have had waste pits for centuries. It’s not like you would smell it on Mars. I wonder what they do with those sorts of wastewater in Antarctica?

Nicolas
2008-Nov-21, 12:56 PM
My point was that when you use water like that, it's lost forever, so you may want to recycle it as much as possible

samkent
2008-Nov-21, 01:31 PM
But that's not the history of humans.

PraedSt
2008-Nov-21, 01:37 PM
But that's not the history of humans.
We have a water cycle here samkent. Whatever we dump, comes back.

Not to say we won't waste water on Mars. If we do, the colony won't last long; if we don't, it'll last longer. So what exactly are we arguing about here? :)

marsbug
2008-Nov-21, 01:45 PM
There's a water cycle on mars to. Its a (99.9% to 100%) solid to vapour and back again cycle but if we dumped a load of used water into a pit on the surface it wouldn't disappear, it would either sublimate into the atmosphere and get redeposited somewhere cold enough for ice, or if it were covered over it would just sit there.
If our base is next to a buried glacier the glacier would make a good cold trap, so it's perfectly possible what got dumped would come back, or at last be around for recycling for a good long while.

If getting to mars were as easy (relatively) as getting to the moon there'd be no comparison for which'd be easier to put a science base / colony on. Of course bases on both would be best of all.

PraedSt
2008-Nov-21, 01:56 PM
There's a water cycle on mars to. Its a (99.9% to 100%) solid to vapour and back again cycle but if we dumped a load of used water into a pit on the surface it wouldn't disappear, it would either sublimate into the atmosphere and get redeposited somewhere cold enough for ice, or if it were covered over it would just sit there.
Good point. But if it escaped into the atmosphere, wouldn't a lot of it escape all together? Mars can't hold on to much of an atmosphere, can it? I seem to have read that somewhere. I may be wrong of course.

samkent
2008-Nov-21, 02:25 PM
wouldn't a lot of it escape all together?

That was my impression as well. Otherwise we would have a lot of frozen lakes.
If we had 60 degree water feed into an open ended pipe, wouldn't most of it boil away before the rest froze solid?

PraedSt
2008-Nov-21, 02:50 PM
If we break it down for the O2 we will just dump the H and excess CO2 overboard.
What's this reaction, by the way? You using methane?

marsbug
2008-Nov-21, 03:04 PM
Good point. But if it escaped into the atmosphere, wouldn't a lot of it escape all together? Mars can't hold on to much of an atmosphere, can it? I seem to have read that somewhere. I may be wrong of course.

The impression I've got is that the lack of magnetic field is much more responsible, allowing the solar wind to gradually sandblast the atmosphere away. Thats quite a slow process, I've read that mars might have had an atmosphere up to half as thick as earths when its magnetic field was still strong, and its taken three billion years for it to erode down its current state.

Besides the atmosphere holds enough water vapour to cause clouds, fogs, frost and snow for billions of years, and mars still has plenty of H2O.


That was my impression as well. Otherwise we would have a lot of frozen lakes.
If we had 60 degree water feed into an open ended pipe, wouldn't most of it boil away before the rest froze solid?

In the pipe the water would generate enough pressure by itself to stay liquid, once it left the pipe I imagine what happened would depend on how big the pipe was and how fast the water was flowing. If it was a reasonable sized pipe and the flow was pretty quick (and the exit was fairly close to the ground) some of the water would probably make it to the ground as a liquid, the surface of the puddle would freeze over, and the water trapped underneath would freeze top down, much more slowly, over hours or days.

I'm not sure but i seem to remember that if you have a BIG pipe and a fast flow you could make an iced over puddle that would last for several days even on the moon. Don't take my word for that though....

There's enough on mars for oceans, the only reason it's not as frozen lakes is becaus the geology and atmosphere have been shuffling it about for billions of years since liquid H2O stopped being a common feature.

cjameshuff
2008-Nov-21, 03:16 PM
What's this reaction, by the way? You using methane?

I think he means electrolyze it for O2, discard the H2, and extract and dump exhaled CO2. Might just pressurize it and let it cool to outside ambient so the CO2 liquifies/freezes.

If you can get a bore into a good sized mass of ice, getting fresh water would be very easy...stick an RTG or resistance heater into the bore to sublimate the ice, and put chiller plates to collect frost at the top. Very wasteful unless the bore is sealed, but assuming equipment to drill such holes for core samples is already there, essentially free, especially if the RTG option is used.

PraedSt
2008-Nov-21, 03:48 PM
I think he means electrolyze it for O2, discard the H2, and extract and dump exhaled CO2. Might just pressurize it and let it cool to outside ambient so the CO2 liquifies/freezes.

If you can get a bore into a good sized mass of ice, getting fresh water would be very easy...stick an RTG or resistance heater into the bore to sublimate the ice, and put chiller plates to collect frost at the top. Very wasteful unless the bore is sealed, but assuming equipment to drill such holes for core samples is already there, essentially free, especially if the RTG option is used.
Ah, thanks. For oxygen and fuel then, amongst other things.

'Fresh' water will become waste water inside the colony, right? Might as well recycle it, if it's already been brought in. Seems wasteful to dump it outside. (And I mean the water that's used as water, not what is used as raw material for industry.)

cjameshuff
2008-Nov-21, 04:36 PM
'Fresh' water will become waste water inside the colony, right? Might as well recycle it, if it's already been brought in. Seems wasteful to dump it outside. (And I mean the water that's used as water, not what is used as raw material for industry.)

Recycling is generally energy intensive, requires extra equipment, and consumes chemicals either for purification or for cleaning of equipment. You might collect frost forming from the vapor as it boils off, but a source of easily accessible water ice could make doing anything more than this more expensive than it's worth. Of course, if you've got crops and the water doesn't contain anything that would harm them, use of waste water for irrigation makes sense, and there's little reason to dump water condensed out of the air.

For the waste water with stuff the crops can't tolerate, might just cover a crater with a tarp and dump water in it. Sunlight would warm it during the day, sublimating water from the dirty ice, and frost that forms overnight could be collected from clean surfaces in the morning.

PraedSt
2008-Nov-21, 05:17 PM
Recycling is generally energy intensive, requires extra equipment, and consumes chemicals either for purification or for cleaning of equipment.
Yeah, I know the process might not be justified on cost grounds, but the idea of waste on a relatively barren planet just seems wrong to me.



For the waste water with stuff the crops can't tolerate, might just cover a crater with a tarp and dump water in it. Sunlight would warm it during the day, sublimating water from the dirty ice, and frost that forms overnight could be collected from clean surfaces in the morning.
This is what I'm taking about. This is cheap recycling.

From what you said here, it occurs to me that water purification on Mars, might be much easier than here on Earth. Would sublimation there, be faster than evaporation here? Much faster? Might not even need to add extra energy- just leave all the waste water at ambient, and collect as much of frost as possible.

samkent
2008-Nov-21, 05:31 PM
If the pit were uncovered most of the frost would blow away before collection.
If it was covered you could collect frost until it freezes.

In either event I doubt it would be worth the effort to collect the residual byproducts. It’s not like it’s going to contaminate the ground water. Which is why I suspect we will opt for the simplest methods at the expense of the environment.

JonClarke
2008-Nov-21, 10:25 PM
If the pit were uncovered most of the frost would blow away before collection.
If it was covered you could collect frost until it freezes.

In either event I doubt it would be worth the effort to collect the residual byproducts. Itís not like itís going to contaminate the ground water. Which is why I suspect we will opt for the simplest methods at the expense of the environment.

I suspect otherwise. Mars settlers will be recyclers and environmentalists to a degree that on Earth would be regarded as fanaticism.

First, casual contamination of the environment is not acceptable in civilised societies. Second, safety first. Leaving wastes about in the environment is unhealthy and unsafe, and pays no attention to long term aspects. Third, the wastes are not really waste, but potential resources, composed of material imported at great expense.

I really don't understand why so many people think that we can degenerate to the worst type of behaviour with respect to the environment the moment we leave Earth.

RGClark
2008-Nov-22, 05:08 PM
Anyone know how thick is the dust over cover of the glaciers?
There have been theories that might be relict glaciers left at near equatorial locations on Mars, but the consensus view is that they should have sublimated away even with a dust over cover.
However with Mars Phoenix showing water ice precipitation occurs in the north polar region that raises the possibility it could very well occur at other locations on Mars thus providing the water precipitation to replenish the glaciers.

==================================
01-October-2008, 04:59 PM
RGClark
Senior Member
Join Date: Feb 2004
Location: Philadelphia, PA

...
Obviously, the important thing here is that it was water ice snow that was shown to be falling at the Phoenix site. The previous observations showed that CO2 snow could fall at the south pole.
This is important because it will suggest the possibility this can be wide spread on Mars, which will have important implications for the Mars water cycle.
Two very key questions it can have application to are the observation of geologically recent glaciers on Mars and the high H2O content from GRS readings even at equatorial locations.
For the first, glaciers normally require precipitation to be active, but these recent glaciers would have been active during the current geological epoch where the possibility of water precipitation has been largely disregarded.
For the second, the question was always asked where could this water have come from for this water at the equator? Answer: because of the extensive and frequent systems of clouds near the equator they could have provided wide spread water deposition near the equator from cloud precipitation.


Bob Clark
==============================
http://www.bautforum.com/space-exploration/78062-phoenix-mars-extended-mission-6.html#post1334859

Notice also that the Hellas basin where some of the still existing glaciers were found is frequently a site of low lying clouds/fogs.

Martian Clouds.
...
"Fog
Fog often appears in low-lying areas. It typically occurs in the southern hemisphere especially in the Argyre and Hellas basins. It forms frequently in craters. Occasionally, it occurs in higher regions such as Sinus Sabaeus and Solis Planum."
http://www.solarviews.com/eng/marscld.htm#views

Image of fogs over Hellas:
http://www.solarviews.com/raw/mars/fog.gif

Bob Clark

PraedSt
2008-Nov-22, 06:52 PM
We so obviously need to go there. :)

JonClarke
2008-Nov-23, 02:21 AM
Hellas has many attractions for a crewed mission already. This just adds to them.

borman
2008-Nov-23, 02:53 AM
Is it not odd that Hellas should have so much water and yet so few gulllies?

samkent
2008-Nov-24, 01:25 PM
First, casual contamination of the environment is not acceptable in civilised societies.

Have you looked on the sides of the roads lately?



Second, safety first. Leaving wastes about in the environment is unhealthy and unsafe, and pays no attention to long term aspects.

We have had poo pits for centuries, just skirt the perimeter on your evening walk and you’ll be fine. Besides you will have a helmet on with fresh air.


Third, the wastes are not really waste, but potential resources, composed of material imported at great expense.

Have you seen the size and complexity of treatment plants? We don’t even try it on the ISS. I’ll bet it’s the poo pit on Mars. It's cheaper.


I really don't understand why so many people think that we can degenerate to the worst type of behaviour with respect to the environment the moment we leave Earth.


Past behavior.

marsbug
2008-Nov-24, 02:40 PM
I suspect otherwise. Mars settlers will be recyclers and environmentalists to a degree that on Earth would be regarded as fanaticism.

I have to play devils advocate here: mars is a dead, or near as makes little difference. What is there to be enviromentalist about?

If anything mars settlers will be looking to change the environment, making it more compatible with life. A human waste/water pit would be a phenomenal resource of water mixed with food for any microbe trying to gain a foothold in the martian environment. If the settlers want to spread life to mars such pits might not just be ok but encouraged. Recycling more than you absolutely have to might be frowned upon.

It may have been Carl Sagan that said : 'I like mars just fine the way it is' but with all respect to him I disagree; however strange and wonderfull mars is today a 'living' world would be much more interesting.

JonClarke
2008-Nov-24, 08:55 PM
Is it not odd that Hellas should have so much water and yet so few gulllies?

It is odd. The ones that are there are all, or nearly all, concentrated along the edges of Dao Vallis too, which has many glacier-like features.

Jon

JonClarke
2008-Nov-24, 09:06 PM
Have you looked on the sides of the roads lately?

I don't know what benighted but of the world you like in, but road side littering is not acceptable in my part of the world. people who get caught are fined. Volunteers and paid local government people clean up after the idiots who do.



We have had poo pits for centuries, just skirt the perimeter on your evening walk and youíll be fine. Besides you will have a helmet on with fresh air.

We gave had typhoid, colera, dysentry for centuries too, does that make the practice of leaving uncovered waste desirable?



Have you seen the size and complexity of treatment plants? We donít even try it on the ISS. Iíll bet itís the poo pit on Mars. It's cheaper.

Have you seen the size and mass of incinerating toilets? They are negligible.

Poo will be a resource on Mars, expecially for settlements. It will be processed, sterilised and mixed with compost for horticulture. It is far too valuable to be left in pits.



Past behavior.
Lots of things were done in the past that we don't accept now. Mars missions will be held to future standards, which will be higher than those of the present. You are proposing a regression to the pre industrial era.

Jon

JonClarke
2008-Nov-24, 09:30 PM
I have to play devils advocate here: mars is a dead, or near as makes little difference. What is there to be enviromentalist about?

For several very obvious reasons, some of which I have pointed out already.

1) Standards are much higher now that the last. Witness the massive clean up of Antarctic bases in the past decade. A lot of cost could have been saved had people been more responsible in the past. If we go to Mars for the long term we will need to consider long term issues.

2) Human waste will be too valuable to leave lying round. They are a valuable source of organics and nitrates. Poo will be recycled into compost and used.

3) Anything left lying round outside will blow round. What blows round contaminates surfaces, surface materials and equipment. Contaminated material will be brought back inside. Not a good idea.




If anything mars settlers will be looking to change the environment, making it more compatible with life. A human waste/water pit would be a phenomenal resource of water mixed with food for any microbe trying to gain a foothold in the martian environment. If the settlers want to spread life to mars such pits might not just be ok but encouraged. Recycling more than you absolutely have to might be frowned upon.

We don't know what will motivate Mars settlers so we can't assume they will want to change the environment beyond what is absolutely neccessary.

That said, there probably won't be sewage to spare and if there was, the pathogens that inhabit it aren't the sort of bugs we want making a footfold.

If Mars settlers decide that it would be good to esablish a soil biota (assuming any could survive) it would not be with as a random experiment with raw sewerage but heavily processed nutrients and carefully innoculated with non-pathogenic organisms that would produce the desired result.

Of course we should never under estimate human stupidity, but stupid people are unlikely to get to Mars.


It may have been Carl Sagan that said : 'I like mars just fine the way it is' but with all respect to him I disagree; however strange and wonderfull mars is today a 'living' world would be much more interesting.

You are misreading Sagan. He was not talking to people advocating future settlement (which he supported), but to those disapointed post Viking that Mars seemed lifeless.

borman
2008-Nov-26, 04:10 AM
It is odd. The ones that are there are all, or nearly all, concentrated along the edges of Dao Vallis too, which has many glacier-like features.

Jon

In one of the upcoming AGU abstracts, Steve Squyres noted that aquifers with CaCl seemed a viable way to source water. The context was in relation to gully formation, but it may also apply as a replenishing source for these glaciers. The ice being thick enough to mask the thermal signature from THEMIS view and the dust and rock covering making it difficult for CRISM to identify a CaCl signature. But maybe a few looks might spot traces of CaCl where the glacier is sourced to lend credence to an ongoing present aquifer source to offer an alternative to polar wander.

PraedSt
2008-Nov-26, 07:35 AM
Recycling on Mars, isn't a matter of environmentalism. For me it's just common sense. (Which might mean I'm wrong of course). Anyway, this is how I look at it:

1. The surface of Mars is hostile.
2. We'll therefore have enclosed colonies.
3. (1) makes transport into, and out of, (2), expensive and dangerous.
4. The more movement across a boundary, (1)/(2), the less secure is said boundary.

This leads me to conclude that recycling anything you've already got in (2), is the way to go. :)

JonClarke
2008-Nov-26, 11:28 AM
In one of the upcoming AGU abstracts, Steve Squyres noted that aquifers with CaCl seemed a viable way to source water. The context was in relation to gully formation, but it may also apply as a replenishing source for these glaciers. The ice being thick enough to mask the thermal signature from THEMIS view and the dust and rock covering making it difficult for CRISM to identify a CaCl signature. But maybe a few looks might spot traces of CaCl where the glacier is sourced to lend credence to an ongoing present aquifer source to offer an alternative to polar wander.

Thanks, I will look for that one.

marsbug
2008-Nov-26, 03:54 PM
Again I'm playing devils advocate, and I'll stop soon I promise:




1) Standards are much higher now that the last. Witness the massive clean up of Antarctic bases in the past decade. A lot of cost could have been saved had people been more responsible in the past. If we go to Mars for the long term we will need to consider long term issues.

Antartica has wildlife, mars does not, perhaps not even microbes. High standards of avoiding contamination, for their own sake, are pointless, and actually make a powerfull argument for us not to go at all. If there is nothing on mars we wish to protect from our waste, or if a fairly high degree of contamination would not damage what we seek (like rock strata, scientifically interesting but largely immune to beeing weed on), why should we avoid contamination?


2) Human waste will be too valuable to leave lying round. They are a valuable source of organics and nitrates. Poo will be recycled into compost and used.

I agree, but why should it be compost for something in a sealed greenhouse? Why should a piece of compost not be mixed into a patch of soil to provide an extra boost for something we think might have a chance of survival in the martian environment? If thats our long term goal surely feeding those nitrates and organics into the environment when we can is resource well spent?


3) Anything left lying round outside will blow round. What blows round contaminates surfaces, surface materials and equipment. Contaminated material will be brought back inside. Not a good idea.

I agree, but I think this is more a case of using common sense when we plan our base: I'm not going to advocate throwing poo around like snowballs the moment we get out the airlock, but properly processed 'compost' could be left outside at a safe distance. We don't fear the compost we spread on our gardens, or picking up our dogs turds, so long as we use some common sense measures, why should that change on mars?


We don't know what will motivate Mars settlers so we can't assume they will want to change the environment beyond what is absolutely neccessary.

Agreed, but nor can we assume they wont.


That said, there probably won't be sewage to spare and if there was, the pathogens that inhabit it aren't the sort of bugs we want making a footfold.

Again I think there are some minimum measures we will need to take as common sense, but I don't see why we should go beyond that. There are as many beneficial or neutral bacteria as pathogens in faeces (unless you have a bad tummy, an occurance of which might well alter things), and many differ from each other only by the tiniest degrees. If we establish anything on mars we face the near certainty that somewhere down the line some strain of it will turn on us- unless we decide to establish a biosphere on mars and never interact with it!


If Mars settlers decide that it would be good to esablish a soil biota (assuming any could survive) it would not be with as a random experiment with raw sewerage but heavily processed nutrients and carefully innoculated with non-pathogenic organisms that would produce the desired result.

I agree, although I would prefer as much randomness as people are prepared to chance to be introduced- I have a lot of respect for life's ability to adapt, I believe it should be left to do it's own thing as much as possible.


Of course we should never under estimate human stupidity, but stupid people are unlikely to get to Mars.

The supposedly very intelligent are often capable of apallingly stupid acts!



You are misreading Sagan. He was not talking to people advocating future settlement (which he supported), but to those disapointed post Viking that Mars seemed lifeless.

I apologise for quoting him out of context, butI am disappointed that it seemed, and still seems, lifeless. And I would not so much advocate settlement as establishing an independant biosphere on mars, with humanity ideally a minimal presence only there to study what we have set in motion!

JonClarke
2008-Nov-28, 08:45 PM
Again I'm playing devils advocate, and I'll stop soon I promise:

They are all good questionsand comments- keep them coming.

.


Antartica has wildlife, mars does not, perhaps not even microbes. High standards of avoiding contamination, for their own sake, are pointless, and actually make a powerfull argument for us not to go at all. If there is nothing on mars we wish to protect from our waste, or if a fairly high degree of contamination would not damage what we seek (like rock strata, scientifically interesting but largely immune to beeing weed on), why should we avoid contamination?

The wildlife story is only part of it, there is also cleanup to prevent risks to people from the debris of old expeditions. The heritage people have quite excited debates over this, defining what is heritage and what is rubbish and what do do about it! Chemicals, radioactives, fuel, old drugs, biological waste, old food, are all hazardous and decisuous have to be made on a case by case basis as to whether the risks posed by such hazards are such that they need to be removed.

On Mars (and the Moon) we an avoid a lot of these issues by a little more forethought.




I agree, but why should it be compost for something in a sealed greenhouse? Why should a piece of compost not be mixed into a patch of soil to provide an extra boost for something we think might have a chance of survival in the martian environment? If thats our long term goal surely feeding those nitrates and organics into the environment when we can is resource well spent?

Careful seeding by an appropriate compost is not the same as dumping raw sewerage.
This is something we might do eventually, when we have decided that mars is lifeless or that such activities pose no thrat to a martian bisophere (if there is one). But it would be a deliberate panned decision after much research, not an inadvertent one because of lack of thought or care about how to dispose of waste.


I agree, but I think this is more a case of using common sense when we plan our base: I'm not going to advocate throwing poo around like snowballs the moment we get out the airlock, but properly processed 'compost' could be left outside at a safe distance. We don't fear the compost we spread on our gardens, or picking up our dogs turds, so long as we use some common sense measures, why should that change on mars?

I agree. But appropriate measures are quite different from the earlier suggestions in this thread that waste be justdumped outside and covered with a tarpaulin.


Agreed, but nor can we assume they wont.

I think we can assume that anybody going to Mars will have a carefully planned and well thought out appraoch to waset management.




Again I think there are some minimum measures we will need to take as common sense, but I don't see why we should go beyond that. There are as many beneficial or neutral bacteria as pathogens in faeces (unless you have a bad tummy, an occurance of which might well alter things), and many differ from each other only by the tiniest degrees. If we establish anything on mars we face the near certainty that somewhere down the line some strain of it will turn on us- unless we decide to establish a biosphere on mars and never interact with it!

While waste contains beneficial bacteria, the presence of harmful ones means that you don't leave it lying round. We learned that in the 19th century.


I agree, although I would prefer as much randomness as people are prepared to chance to be introduced- I have a lot of respect for life's ability to adapt, I believe it should be left to do it's own thing as much as possible.

Leaving things to chance on space missions is a recipe for disaster.


The supposedly very intelligent are often capable of apallingly stupid acts!

Project Orion being a case in point....

Mistakes will be made going to Mars. Some will be stupids ones. Let's not dd to them by doing things we already know are stupid.



I apologise for quoting him out of context, butI am disappointed that it seemed, and still seems, lifeless. And I would not so much advocate settlement as establishing an independant biosphere on mars, with humanity ideally a minimal presence only there to study what we have set in motion!

Life on Mars would be exciting, but scientifically a lifeless Mars is just as significant. And it does make life easier for exploration.

Why establish an independent bisophere on Mars if not for the purpose of eventual settlement?

Jon

marsbug
2008-Nov-29, 01:26 PM
Thanks for the reply, I was worried i'd come across like I was picking an argument for the sake of it!

I'll start at the end of your post, because it's the matter closest to my heart;
A lifeless mars is scientifically significant, especially if it had habitable conditions in the past, but that just doesn't get me as excited as a living, or even formerly living world.

The image of something growing on another world is one that has stuck in my mind for many years and as beautiful as mars is, if nothing has ever lived there I'll be disappointed. Thatís my personal emotional reaction, not a scientific view.

I'm of the opinion that since mars has had habitable conditions at least for a time in it's past it very likely supported life, and I'm a strong supporter of the search for evidence for or against, but as far as we know (which is about as far as my baby sister can throw my dad right now) mars is dead today. Hence a little kernel of disappointment.

The next bit of my response is based entirely upon the idea that at some point we find mars is dead, always has been dead, and has little more to offer us in its dead state:
I would like to see an independent biosphere on mars because it would be a wonderful thing to exist! I simply don't rationalize it more than that, although I think there are powerful arguments for it: a second planetary home for life, and the opportunity to watch an entire living, alien, world develop from scratch are two I can think of off the top of my head.

I've heard it convincingly argued that if we simply want live away from earth we can do it far more easily with artificial habitats outside of the major gravity wells. Hence a living mars makes more sense to me as a cross between a very long term experiment and a wildlife preserve, and if that is how it gets done human presence would need to be controlled carefully at least.

I also think that making mars into a planet which can support life is a much more obtainable and sustainable goal than a mars which can support humans: reworking mars into a second earth would be gigantic, reworking mars as a planet where liquid water is a more common feature would be more achievable, and might even be doable, in the crudest of ways, with present day or near future technology.

When people get there, waste management and recycling will be a must, safety will be paramount and resources will need to be carefully managed and recycled- thatís a given and I've only tried to argue otherwise because I'm wearing horns!

However some contamination of mars with earth life is inevitable. It has probably already occurred with the number of probes that have travelled there, and certain parts of these probes might even have provided habitable conditions for their passengers. As an example: the water based electrolyte in the mars pathfinder rover batteries has a PH of 12, just inside the growth range for alkali loving extremophiles.

There's no such thing as a 100% clean room, or a perfect sterilisation technique... and the more human presence there grows the more chance there is for unwanted life forms to make the trip.
So we may have to accept that mars will be contaminated, and that our presence on mars may even be creating habitable niches there. If we cannot get away from that then avoiding contamination, for the sake of preserving mars as it is, does not make a lot of sense to me. Avoiding contamination for reasons of safety or efficiency is an entirely different matter.

Minimising contamination, at least until we are certain there is nothing living on the surface or near subsurface, is simple sense.
However when we know the planet is dead, taking fanatical efforts to prevent life forms from colonising the surface strikes me as futile and largely pointless: if astronaughts in 2073 find that conan the bacterium has started growing in the soil just outside their base's airlock, because (for example)base activities are causing that patch of soil to be 'contaminated' with salts that allow minute amounts of H2O to remain liquid under mars conditions, i can imagine the horror from preserve mars groups, but I'd be delighted (i'd also be ninety)!

JonClarke
2008-Nov-29, 11:46 PM
Thanks for the reply, I was worried i'd come across like I was picking an argument for the sake of it!


I'll start at the end of your post, because it's the matter closest to my heart;
A lifeless mars is scientifically significant, especially if it had habitable conditions in the past, but that just doesn't get me as excited as a living, or even formerly living world.

The image of something growing on another world is one that has stuck in my mind for many years and as beautiful as mars is, if nothing has ever lived there I'll be disappointed. Thatís my personal emotional reaction, not a scientific view.

I think you are right, life on Mars is much more emotionally exciting than a lifeless Mars. But a lifeless Mars is just as scientifically important.


I'm of the opinion that since mars has had habitable conditions at least for a time in it's past it very likely supported life, and I'm a strong supporter of the search for evidence for or against, but as far as we know (which is about as far as my baby sister can throw my dad right now) mars is dead today. Hence a little kernel of disappointment.

I would generally agree, although the caveat is whether is is lifeless everywhere, or just where we have looked (three places only).


The next bit of my response is based entirely upon the idea that at some point we find mars is dead, always has been dead, and has little more to offer us in its dead state:
I would like to see an independent biosphere on mars because it would be a wonderful thing to exist! I simply don't rationalize it more than that, although I think there are powerful arguments for it: a second planetary home for life, and the opportunity to watch an entire living, alien, world develop from scratch are two I can think of off the top of my head.

This is the emotional upside of a lifeless Mars. We can settle and perhaps thrive there without worrying about a native biosphere.


I've heard it convincingly argued that if we simply want live away from earth we can do it far more easily with artificial habitats outside of the major gravity wells. Hence a living mars makes more sense to me as a cross between a very long term experiment and a wildlife preserve, and if that is how it gets done human presence would need to be controlled carefully at least.

I am not convinced by the artifical habitats idea, although they are a marvellous vision. Gravity wells have lots of advantages that people sometimes overlook.


I also think that making mars into a planet which can support life is a much more obtainable and sustainable goal than a mars which can support humans: reworking mars into a second earth would be gigantic, reworking mars as a planet where liquid water is a more common feature would be more achievable, and might even be doable, in the crudest of ways, with present day or near future technology.

I think you are right here. What you are proposing is called ecopoesis rather than terraforming.


When people get there, waste management and recycling will be a must, safety will be paramount and resources will need to be carefully managed and recycled- thatís a given and I've only tried to argue otherwise because I'm wearing horns!

:)


However some contamination of mars with earth life is inevitable. It has probably already occurred with the number of probes that have travelled there, and certain parts of these probes might even have provided habitable conditions for their passengers. As an example: the water based electrolyte in the mars pathfinder rover batteries has a PH of 12, just inside the growth range for alkali loving extremophiles.

There's no such thing as a 100% clean room, or a perfect sterilisation technique... and the more human presence there grows the more chance there is for unwanted life forms to make the trip.
So we may have to accept that mars will be contaminated, and that our presence on mars may even be creating habitable niches there. If we cannot get away from that then avoiding contamination, for the sake of preserving mars as it is, does not make a lot of sense to me. Avoiding contamination for reasons of safety or efficiency is an entirely different matter.

I think you are right. I heard a lecture by Chris McKay a few weeks ago, he said that ost Viking NASA has not sterilised its Mars landers, only cleaned them, taking the view that the surface was sterile and hostile enough. Special components - sampling arms, analytical instruments designed to look for organics etc., are sterilised. So we have, almost certainly, "contaminated" Mars already.

The point is the surface is very hostile. Very high UV which rapidly destroys organic molecules is the start. While the shallow surfsurface will stop the UV, there is still the low pressure, high cosmic rays, high salts (not everywhere), oxidants, massive temperature swings, absence of water much of the time. There are bugs that wil live under some of these conditions, but not all. They will kill most spores, although some will survive for a while.

But humans presence will contaminate the surface. Suits will leak air, and any microbes, virii etc, along with them. It will be impossible to stop, just as it will be impossible to stop Mars getting in to the station.



Minimising contamination, at least until we are certain there is nothing living on the surface or near subsurface, is simple sense.

Yes, this is the precuationary principle, and good housekeeping.



However when we know the planet is dead, taking fanatical efforts to prevent life forms from colonising the surface strikes me as futile and largely pointless: if astronaughts in 2073 find that conan the bacterium has started growing in the soil just outside their base's airlock, because (for example)base activities are causing that patch of soil to be 'contaminated' with salts that allow minute amounts of H2O to remain liquid under mars conditions, i can imagine the horror from preserve mars groups, but I'd be delighted (i'd also be ninety)!

I suspect that, if Mars is known to be dead with some high level of certainity then procedures will be relaxed and there willprobably be outside experiments to see what can be made to live there.

Jon

PraedSt
2008-Nov-30, 08:47 AM
When people get there, waste management and recycling will be a must, safety will be paramount and resources will need to be carefully managed and recycled- thatís a given and I've only tried to argue otherwise because I'm wearing horns!Made me smile too. :)
You live up to your handle in this post Marsbug.

marsbug
2008-Nov-30, 12:44 PM
I couldn't ask for a better compliment. I think we're all thinking along the same lines here, I just hope I live to see some of it! :)


I am not convinced by the artifical habitats idea, although they are a marvellous vision. Gravity wells have lots of advantages that people sometimes overlook.

There are points for and against both, has there been a thread specifically for discussing this?

PraedSt
2008-Nov-30, 12:57 PM
Yes! Mine! (http://www.bautforum.com/questions-answers/79495-planetary-colony-orbital-habitat.html) :)

I don't like gravity wells myself. Feel free to start another Marsbug, I would gladly participate.