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#26 2012-04-23 20:42:10

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Solar Enclosure Architecture On Mars

Finally got a moment to read about the spray on glass and its a Coating and not like glass that we would see as a structural part of an enclosure/window or wall of panes....in which a greenhouse would be made. Yes it could be sprayed onto a sheet of plastic to be a protectant as it is but so could lots of anti uv or reflective chemical combinations.... There is also another form that is temperature set http://en.wikipedia.org/wiki/Sodium_silicate


A slightly higher than mars current pressure within such an enclosure would benefit the plants but designed with humans working for short periods of time without suits would be a plus. These structures would not need to cover acres as even a few hundred square feet connect from one area to another by tunnels would allow for independant sealing of each section from the next. The slightly higher atmospheric pressure would also be better for liquid water for ponds to be created.

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#27 2012-04-24 07:22:14

Glandu
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From: France
Registered: 2011-11-23
Posts: 106

Re: Solar Enclosure Architecture On Mars

SpaceNut wrote:

For mars construction from insitu materials go to http://marshome.org/ look to he document library for what you are in search of for works that have been done already.

The Mars Homestead™ Project, the main project of the Mars Foundation™, is developing a unified plan for building the first habitat on Mars by exploiting local materials.

The ultimate goal of the project is to build a growing, permanent settlement beyond the Earth, thus allowing civilization to spread beyond the limits of our small planet.

I'm very skeptical of all this. I've read all their docs, & it's full of optimistic simplifications. I've got an engineering diplom in plastics manufacturing, & I think it's enough to allow me to dismiss most of their plans for polymers(where are the additives? How do you maintain the extrudor screw?.....). A little knowledge is often worse than no knowledge at all, & at least on the plastics part, they are exactly in that position.


[i]"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation."[/i] (Alistair Cockburn, Oath of Non-Allegiance)

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#28 2012-04-24 15:34:13

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Solar Enclosure Architecture On Mars

Glandu wrote:
SpaceNut wrote:

For mars construction from insitu materials go to http://marshome.org/ look to he document library for what you are in search of for works that have been done already.

The Mars Homestead™ Project, the main project of the Mars Foundation™, is developing a unified plan for building the first habitat on Mars by exploiting local materials.

The ultimate goal of the project is to build a growing, permanent settlement beyond the Earth, thus allowing civilization to spread beyond the limits of our small planet.

I'm very skeptical of all this. I've read all their docs, & it's full of optimistic simplifications. I've got an engineering diplom in plastics manufacturing, & I think it's enough to allow me to dismiss most of their plans for polymers(where are the additives? How do you maintain the extrudor screw?.....). A little knowledge is often worse than no knowledge at all, & at least on the plastics part, they are exactly in that position.

Are polymers necessary?  What are they being used for?

Effective sealing can be obtained using ice and regolith cover I think. Maybe internal walls could be double lined with basalt tiles.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#29 2012-04-25 03:31:03

Glandu
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From: France
Registered: 2011-11-23
Posts: 106

Re: Solar Enclosure Architecture On Mars

louis wrote:

  (.../...)Are polymers necessary?  What are they being used for?

That's my point : they are not necessary. Those guys think they are, don't know them well, and therefore make unrealistic plans for using them. I therefore think their credibility on other topics is limited.

louis wrote:

Effective sealing can be obtained using ice and regolith cover I think. Maybe internal walls could be double lined with basalt tiles.

Ice I fear for life zones. It melts. But you are globally right : there must be plenty of other solutions. Just polymers might be not the best idea, especially in the beginning, with a small industrial base.


[i]"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation."[/i] (Alistair Cockburn, Oath of Non-Allegiance)

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#30 2012-04-25 18:35:43

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

Glandu and Louis,

I simply was unable to understand your dialog.  Therefore in the details, I will not dwell, unless, there is something I missed which you want to explain in explicit language.  A good part of it or all of it was about the reference that Spacenut gave us.

One thing around here is the compulsion to put a wet blanket on creative thinking.  That is citing that something is not the best to try to do at least not in the beginning.  However, it will be at least 15 years before humans even to go Mars to visit, let alone settle.  More like 30 +++++++++++!

Those children who are having their imaginations stimulated by symbolic illustration, may in many cases go on to create major changes in the equasion of what is best to try to do first for the first settlement.  A whole new science could be invented by then.  Now is not the time to limit possiblities.  Expressing a concern is just fine, telling people just to give up is wrong.  It is not how the west was won.


Done.

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#31 2012-04-25 19:00:19

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

OK you are really in luck.  More free philosophy from yours truely! smile

I will go to the gym tonight as I often do.  It has done me incredable good to have that practice.
One deficiency I have is in my legs.  So, my trainer often has me doing squat type exercises, which I do.  I do them because I know that my legs will get stronger.

It is my opinion that with a real Mars settlement mission 15-30+++ years off, then if you have a hard time with Polymers, then work on that.  Don't go run and hide and do the easy.  The people who settle Mars will need every single trick that can be thought of, and even then there is a possiblity of there extinction.

When a mission finally gets launched, then those who are there can choose what to keep and what to set aside.

When I say something like I don't know much about plastics, that is only a half truth.  I have calibrated temperature controllers for injection moulds, I have changed the probes.  I have figured out solutions for such. 

So in my equasion I cited a film to cover the ice/ice water.  A transparancy.  If it were true that polymers are forbidden on Mars, or can't work on Mars, even then I could turn to glass, or who knows "Transparent Aluminum", or terraform the planet and get the pressure up so the ice will be stable without an auxiliary covering.

The point is if I cite a variable "X", so that I can work on the issue "Y".  I would prefer that I do not get the bums rush out the door, if simply because you have concerns about "X".  Talk directly to me about that issue.  Don't go get a buddy and do a double team on me.

It is extrordinarly wrong that there is a compulsion to impose orthodoxy in a question that requires that a new book be written, and does not demand that a recipe be followed.  Following recipies, is a survival skill of our species, and I would never dispense with it, but it is not experimentation. 

The tried and true never got anyone to Mars, let alone caused them to thrive there.

Last edited by Void (2012-04-25 19:05:25)


Done.

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#32 2012-04-25 19:16:26

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

Well about vapor pressure:

www.vaxasoftware.com

http://www.vaxasoftware.com/doc_eduen/qui/pvh2o.pdf

http://en.wikipedia.org/wiki/Water_(dat … se_diagram

700px-Phase_diagram_of_water.svg.png

Well I guess that will do.  As I have seen it, it appears that if Hellas eventually and optimistically had a 23 Millibar pressure then 70 DegF/23 DegC would be the boiling point of water.  So, having ice water or even water at 39 DegF/3.89 DegC is quite reasonable, and even higher could be considered.  So, an effective vapor barrier would not be used to suppress boiling with internal pressure relative to the external pressure, but would be a vapor barrier to inhibit evaporation.

In current terms it is my opinion that water kept at 32 DegF / 0 DegC would be stable in the bottom of Hellas, if given a vapor barrer, to keep the dryness and the winds of the atmosphere from stripping off the water.  Of course it is desired to let the photons in to promote photosynthisis.

And if you would criticize that then consider that sea life including plant life I believe, can in fact work in water considerably colder than that if it is salt water.  Therefore the vapor pressure of that solution would be less than 6.1 Milliabars.

In fact I believe that the current maximum pressure at the bottom of Hellas is > 11.466 Millibars, and that 11.466 Millibars allows for a boiling point of 48.2 DegF.

So, I am rather inclined to say that smile I was not Optimistic about what could be accomplished! smile I was consirvative!

Yes, and there is more, I don't care if the ice melts for a few weeks in the summer.  Actually that would mimic the Arctic Tundra pond environment very well.

In fact that could allow for emergent plant life.  However, now my problem is how do you keep alive and active a polinator type insect or other mobile animal that could polinate.  I know that the Mona Loa bug on the top of Hawaii can live well below freezing, but how to give it resperation.  (And of course it is not a polinator).
In the Hymilayas are insects with antifreeze which also can work well below freezing.  Still how does a insect survive on 12 or less Millibars of Oxygen/Nitrogen mix?
My estimation is that is it unsolvable, but I will still think about it.

One thing I will not think about is Misquitos on Mars.  I will swat them if they exist.

Last edited by Void (2012-04-25 19:44:21)


Done.

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#33 2012-04-28 16:39:05

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

Void:

Midoshi pointed out to me some time ago that atmospheric pressure is not the same as vapor pressure,  in terms of the phase diagram for water.  And he was right,  too. 

What keeps ice from sublimating at 0 deg C is an applied (partial) pressure of water vapor of 6 millibars.  Dry mostly-CO2 will not serve that purpose:  the exposed ice just sublimates,  and also any liquid water phase just boils away.  That's what Mars has right now. 

It might be possible with minimal terraforming to achieve an atmospheric pressure in the Hellas Basin of 23 mbar,  but,  how much of that pressure is water vapor partial pressure?  I dunno,  but,  until you have 6 mbar of water vapor partial pressure in Mars's atmosphere at 0C liquid temperature,  liquid water and ice are simply not stable.  Period. 

That being said,  I really am a fan of trying to terraform Mars.  But,  I am sure it will take a lot more than 23 mbar in Hellas Basin to accomplish that end. 

How about 2 psia (0.14 atm,  140+ mbar) total atmospheric pressure?  If nearly-pure oxygen,  that would be good enough for humans to breathe without a pressure suit,  but would still require an "oxygen mask" (really a pressure-breathing rig).  Assuming it was not destroyed during terraforming,  6 mbar of that (about 4%) would be the original CO2 atmosphere.  But,  at 1% (just a wild guess) absolute (not relative!!!!!!) humidity,  that would still be a water vapor pressure too low at 1.4 mbar to stop exposed ice sublimation,  and exposed water boiling away. 

Any terraformed Mars will require a still-denser atmosphere to ensure stable ponds and lakes,  even if ice-covered.  Maybe 4 times the 2 psia oxygen I proposed just above. 

That's about the limit of what I know.  Maybe some others could shed better light on this. 

GW

Last edited by GW Johnson (2012-04-28 16:44:09)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#34 2012-04-29 07:38:41

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

GW Johnson

I think that baisically we are on a similar page.

You want the glass full, and I am trying to deal with it only partially full.

However, to fill it first comes a point where it is partially full.  So I am trying to find alternate methods for agriculture for that period of time where Mars is only partially terraformed, or initially terraformed.  Economics will not pay for the terraforming of Mars, unless it can be utilized effectively during the terraforming process.

It will have to pay it's own way.   There will have to be a point in time where agriculture of some kind is possible in one place on Mars above others, and I think that could be Hellas, so I use it for my example.

I have suggested as my most optimistic proposal, uncovered irrigated fields.  If Mars were terraformed to have 23 Millibars in the bottom of Hellas, then indeed ice water could be squirted onto Reindeer Moss fields, and it would in fairly short time evaporate from the surface, but some droplets would be retained in the soil.  Eventually they would evaporate.  In fact right now, if the soil in the bottom of Hellas had ice in it and you heated it, droplets of liquid water can persist for a time inside of the soil.  But yes they will evaporate in time.  The water will not boil however at 11.78 Millibars and 0 Degrees C, or if it were even colder salt water.

In the deserts of California, Colorado water can irrigate fields with water.  It does not boil, but in the hot sun it will evaporate.  Droplets of water will persist in the soil, but will eventually evaporate.  It does not boil at 1010 Millibars and a temperature of 90 Degrees C.

So I have to say that that it is mechanically possible.  You are correct, water is unstable.  It also is in California.

So, the next important factor is Economics, or Practicality, whichever you might prefer.

I have suggested irrigation water from the ground, and then the Glaciers in Hellas, and then the South Polar Ice Cap.

Practicality and Profit would determine if it were to be done, the movement of sufficient water to the bottom of Hellas. 

As for the choice of an open field or a covered field, that is also based on economics and practicality.  The value of the water.  If its expensive water then consirving it matters.  A covering which retains mositure might make economic sense.  Also, if a temperature above freezing cannot be achieved in an open field, then a covering is also desired.  And of course there is the matter of Ultra Violet light.  If no ozone layer exists, then a covering is a must, and it must protect the fields from UV damage.

Reindeer Moss exposed to atmosphere is actually an ambitious and perhaps poor choice relative to Moss which will grow under water, and likely under water which is under ice.

So for the purposes of water consirvation, I prefer ponds covered by Ice, and that ice covered by a vapor barrier, and then the mechanical enclosure must also at a minimum provide UV protection. 

Beyond that if it is economically correct, such enclosures might have a greater internal pressure, but then if they leak that leakage takes moisture with it.

In the bottom of Hellas, a large plastic bag filled with ice water will not boil, and will not evaporate beyond the permeability of the plastic to moisture, or if the bag should be punctured.  (Here I am presuming that the bag is kept at 0 Degrees C).  The pressure inside of such a flexible bag should be ambient atmospheric pressure + the pressure of the static water column.  So for the best present case, 11.78 Millibars + whatever debth of water you are measuring the pressure at.

The question is can enclosures be created which are as effective as a plastic bag?  Another is can make up water be gathered at an economic cost to replace losses that are indeed assured to occur?  And finally are the plants that can be grown of a reasonable economic value to justify the effort?

Selective breeding and genetic engineering may alter the answers.

Finally I want to point out that the reason to have a layer of ice is so that the surface is colder than 0 Degrees C.  This depresses the vapor pressure, and reduces the evaporation rate.  At the same time it increases the pressure of the liquid water, a sort of counter pressure suit for a pond.  Yes if exposed, it will evaporate to the atmosphere, but be less inclined to do so than open water.

If for some reason an enclosed pond were created at the bottom of Hellas, then I estimate that for about 11? months, the pond might be frozen solid, and the ice surface temperatures would be very low.  This would be winter.  It is possible to add heat to allow liquid water, to utilize the scaps of sunlight that would occur in the winter, but the Summer would be the favored time to utilize sunlight with long days, and shorter nights.  So 1/2 of the year, water would be easily consirved with a moisture cover.  Then for most of the summer, the pond would be ice covered ice water.  Then if it were favorable to the plants inside, perhaps a few weeks in the summer, the surface ice could be allowed to melt.  At this time period the risk of loss of water to atmosphere would be largest, but then that would be the logical time when the moisture barrier would have previously refirbushed to it's maximum effectiveness.

If irrigation water is available, then these are economic and not purely mechanical questions.

If I have expressed any science errors here I prefer to know about it.

Last edited by Void (2012-04-29 08:51:40)


Done.

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#35 2012-04-29 10:35:07

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Solar Enclosure Architecture On Mars

Were those droplets of liquid on the Phoenix lander every properly explained. They were ocurring in a polar region!   I think it was suggested they might be water saturated with salt.

Presumably you can grow some things in briney water...seaweed for instance.

Last edited by louis (2012-04-29 15:04:27)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#36 2012-04-29 12:08:20

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

Salt tollerant water plants might be able to operate in below zero water.

I am tapering off, going to take a long break.  Thanks Lewis & GW Johnson.  If I have offended anyone else on this site, I give appogies.

I will look into visiting again in a few months.


Done.

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#37 2012-04-29 15:05:54

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

I think that one could build an ice-covered pond,  covered in turn by around 6-15 inches of regolith,  and have stable fresh water underneath.  The ice would be stable under the regolith.  We've already seen that on Mars. 

If the ice were a few meters thick,  the pressure in the covered water would be high enough that a human diver on pure oxygen would not need a pressure suit.  Just a wetsuit to stay warm at 0 C,  and a pure-oxygen SCUBA,  would work. 

The way to keep the water liquid under the ice is the same as that required to grow aquatic Earth plants:  use a sunlight-simulating electric lamp.  Hence,  it is possible right now to grow aquatic plants anywhere on Mars. No terraforming required.  This is the best way I can imagine to turn acres and acres of surface to productive agriculture without building any sort of pressure domes. 

Actually,  it might even be made to work on the moon.  Or,  the asteroids. 

There is the energy cost of running the lights.  That's what solar PV and nuclear power are for.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#38 2012-04-30 15:13:19

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

GW Johnson said:

I think that one could build an ice-covered pond,  covered in turn by around 6-15 inches of regolith,  and have stable fresh water underneath.  The ice would be stable under the regolith.  We've already seen that on Mars. 

If the ice were a few meters thick,  the pressure in the covered water would be high enough that a human diver on pure oxygen would not need a pressure suit.  Just a wetsuit to stay warm at 0 C,  and a pure-oxygen SCUBA,  would work. 

The way to keep the water liquid under the ice is the same as that required to grow aquatic Earth plants:  use a sunlight-simulating electric lamp.  Hence,  it is possible right now to grow aquatic plants anywhere on Mars. No terraforming required.  This is the best way I can imagine to turn acres and acres of surface to productive agriculture without building any sort of pressure domes. 

Actually,  it might even be made to work on the moon.  Or,  the asteroids. 

There is the energy cost of running the lights.  That's what solar PV and nuclear power are for.

GW

I think Lewis might have mentioned this as well.  OK.  I will run with it.  (To be honest I have old archives where I suggested similar for canals to convey water, but I would prefer to lay down a vapor barrier under the soil and perhaps a layer of styrafoam).

However I don't want to be an idea moocher, so other than as a passing comment the above is if little significance.

I see that you are intending to employ native materials.  Ice, water from ice and regolith.
Can we call this the minimum method?  Otherwise to get fancy a large amount of fancy manufactured materials are required for the structure itself.

Later, I would indeed utilize fancy materials, which would allow much higer water temperatures, but you do have a formulation which minimises the burden of such effort intense materials.

I might add that in addition to wired electiric lights, there are the options, of fiber optics to convey solar energy in, and also pneumatic transfer of power to light fixtures with on board turbine generators.  (That way no current carrying conductors in water.  Just sealed lights, and a pressurized air supply, and a pipeline to drain that back to atmospheric vacuum).

Or Steam from solar concentrators, which would push steam through pipes to turn turbines in submirged lighting fixtures.

Or if the lights were LED's and did not give off much heat, then they could be embedded in the bottom layer of the ice, just above the water, and then the wires could indeed be "Dry" inside of "Conduit" inside of slots cut in the ice, and accessable for repairs by digging in the rigolith and cutting the ice.

Further there is the option of Chemosynthisis, where chemicals such as Oxygen and Methane would feed organisms.

I see one weakness in your plan.  The Regolith, has a higher specific gravity than the Ice.  However Trucks drive out on icy lakes and get away with it.  With good engineering and a thick coat of ice it most likely will pass OK.

However if it were a concern, I suggest a trench like pond, so that the ice layer can "Grip" the sides and be stabalized that way.  Even beyond that a serpintine trench which would likely do even better (Not sure). 

The point is, I think we finally have an point of agreement,  a path forward with this.  I am very happy.

Putting up with 0 Degrees C may be a neccessity at first, but as I have said when the economy becomes larger and luxury is more available, I suggest that the rigolith be mixed with styrafoam, to make the mixture have a specific gravity of .9 which matches water ice, and I suggest that large lakes could be the order of the day.  In that case, those rigolith covered lakes could easily have enclosures of materials which would allow temperatures inside well within the comfort zone of humans without suits, and also suitable to any fresh water aquatic life desired.

I also mention in passing that I have read of efforts to make underwater breathing apparatus, which can extract disolved Oxygen from water.  This might be a useful tool.

Thanks for your comments.

Just some links about Mars Ice for those inclined to investigate:


The phrase I googled: "Thickness of subsurface ice on Mars"


http://www.planetary.brown.edu/pdfs/3966.pdf

http://www.ifa.hawaii.edu/~norb1/Papers … eages2.pdf

http://www.sciencedirect.com/science/ar … 3586901703

http://thesis.library.caltech.edu/1586/ … apter1.pdf

http://www-geodyn.mit.edu/mitrofanov.grl07.pdf

http://www.mendeley.com/research/global … -ice-mars/

http://www.upi.com/Science_News/2010/03 … 267625725/

This one:
http://www.universetoday.com/58518/mro- … rtian-ice/
Mars-ice-580x317.jpg




CO2:
http://www.sciencemag.org/content/300/5 … 1.full.pdf

http://www.nature.com/nature/journal/v4 … 05781.html

http://elements.geoscienceworld.org/con … 1.abstract

http://adsabs.harvard.edu/abs/1986Icar...67....1F

http://science.nasa.gov/media/medialibr … TAGGED.pdf

http://www.astronomynow.com/news/n1003/05ice/

http://www.psrd.hawaii.edu/June02/MarsGRSice.html

Last edited by Void (2012-04-30 15:27:20)


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#39 2012-04-30 19:03:33

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Solar Enclosure Architecture On Mars

Void you are not an idea moocher in any way, as that is the nature of open source blogging....but if you reference the place that the words are based from you give credit where due....hopefully I will get to look at all the links later....and thank you.

The water barrier for the artificial pond, sea to keep it from wicking away might not be necessary if its in an area of bedrock...but would not hurt to plan ahead for when constructing it regardless of the materials used.

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#40 2012-05-01 09:35:52

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

There seems to be lots of buried ice on Mars.  Why not dig the ice-covered agriculture pond on a buried glacier?  Then,  the liquid and ice are in equilibrium,  and you don't lose water as a groundwater current into dry regolith.  Except for the cracks in the rock,  digging ponds in bedrock does the same thing.  These are all problems that can be solved. 

I really don't see why acres and acres of Mars's surface cannot be quickly put into aquaculture production with no more sophisticated heavy construction machinery than a bulldozer operable in vacuum.  There might even be a way to do a hydrogen peroxide-hydrocarbon piston engine to power it at high force levels. 

This is not first mission stuff,  but pieces of it should definitely be tried on the first mission or two,  so that this technology will be ready for use on the mission that actually establishes a base of some kind. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#41 2012-05-01 09:40:12

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

Actually,  on the buried glacier,  you start the pond construction by nothing more than pumping heat down a well drilled into the glacier.  The bulldozer is for simply smoothing and adjusting the regolith cover.  Melt out a cavity you can get into,  then "hot fire hose" it to the shape and size you want.  Add habitat with airlocks into the water and on the surface.  Rig the lights.  Add organic matter and transplanted Earth water plants.  Voila:  operating farmland on Mars. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#42 2012-05-01 16:53:34

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

A glacier 1/2 mile thick the size of Los Angeles such as what is thought to exist in Hellas would last quite a long time, being used in the manner you suggest, especially with water consirvation.  Mars would likely be all the way terraformed before it ran out.

I suggest that at convenience, that a feature would be added.  That would be to line the bottom with a layer of rogolith, for a 32 foot deep pond I suggest about 3 feet thick.  (Sorry about the non metric, I think faster native).

That would serve several purposes.
1) Fresh water at 39 degrees F is heavier than fresh water at 32 degrees F.  Therefore the rigolith being an insulator, the bottom of your pond can rise to 39 degrees maximum before the water starts turning over.  (Don't want that, it would melt the ice).

2) It would serve as ballast.  If the pond had an ice floor, there is always a chance that a block of ice would break loose from the lakebed and float up, with the pond water flowing beneith it.  So the 3 foot layer of rigolith is ballast to hold it down.

3) Oxidation.  Substances in a reduced state introduced to the bottom of the pond will "Rust".  This will produce Hydrogen.  Plants growing in the pond will produce hydrocarbon solids, and Oxygen.  Unless the situation is reduced, you cannot have an increase in hydrocarbon mass.  You could if you threw away some of the Oxygen, but why do that?  We would want hydrocarbon mass to make plastics from I am thinking.  So plastics from rusty iron, or other poorly oxidized rigolith.

What comes next here is a trial balloon.  Don't get too warped about it.

I suggest that water from the pond could be boiled in the daytime using solar concentrators.

The steam could be piped under the ice.  Remember that the pressure just under the ice would be perhaps 100 Millibars or more.  This means that the steam will be rather warm, not hot.  It could drive a turbine in a lamp unit to produce electricity to light the lamp.  The light would shin down on the pond floor perhaps 20 feet below?  (The water would have to be exceptionally clear for this to be a good plan)  Perhap the plants would be in plantes attached just below the light fixture.

The warm steam would quench into 32 degrees Faharenheight water and if controlled properly, would leave a residue at 39 degrees Fahrenheight that would fall to the pond floor because it would be heavier than the 32 degree water.

I am thinking of plastic pipes for the steam and condensate.  That is because plastics will print in a 3D printer easier, and the steam temperatures might be low enought that they would not be damaged.

Utilizing this method, it becomes obvious that there is a real danger that the pond will overheat, so;

Ammonia and water mixture carries heat from the pond floor (Don't know that plastic pipe will put up with that, so that could be a problem).
Ammonia is boiled out of the mixture and passed through a turbine at the surface, where the Ammonia is recondensed, and sent back the the mixture.
This of course will be most powerful in the night and during winters.  I am afraid it will requre serious radiators, not plastic ones.  Not certain, but thinking so.

And then there is the possiblity that you can have enclosures inside of the lake, and send some of the steam into them to warm them up, and so those could easily be at higher temperatures than 39 Degrees F.

Final thought.  You could make a styraform tile block, and apply it to the bottom of the ice, inside of the pond, and it would eventually freeze to the ice.  Of course styrfoam can get waterlogged, so some work needs to be done there.

And even more final those styrafoam blocks can have air pockets on their bottoms.  Some parts of the styrafoam blocks deeply submirged, and some having air pockets in concave cavities.

smile

Last edited by Void (2012-05-01 17:10:19)


Done.

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#43 2012-05-01 17:36:34

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

I'm thinking electric lights just because Earth plants need visible light centered at green wavelength,  plus a snit of UV,  to survive well. 

Steam is a very good way to transmit heat,  though. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#44 2012-05-01 19:33:34

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

I agree, I may need to be more clear.  I am not saying it is the only way, but it is a way to investigate.

1) Pipe pressurized steam into the lake using pipelines (Plastic might not hack it).
2) Condense the steam into the 32 degree, or coldest water in the lake.

Have a submersible light fixture with an on board steam turbine and electric generator.

Have the spectrum of light you want.

The whole light fixture assembly hopefully being easily disconnectable from the steam and condenser lines.

The whole light fixture assembly being small enough that a diver could carry it to a workshop for maintenance and repairs.

Virtually all the heat from the steam warming the lake, either condensate process or the light energy not consumed by the plants.

This then avoids the need for a power line system, the conductors and so on.  Just what is internal to the steam powered light fixture.

An alternative would be a pneumatic light fixture, but then you have to have a vacuum line to vent the air pressure out to the Martian atmosphere.

Later:

I have been thinking about it and there is definitely a large issue with the pipes freezing at night.  (Those above ground).  They would have to be drained correctly and without error every late afternoon, or they might freeze and crack.

I still am interested in steam and pneumatics, but what the heck, I guess I could try to make electric wiring work with you.

Do you think that there could be a way to make "Plexiglass" enclosures, a network of them, Jerble tubes sort of, with an internal pressurization above that of the
water they were in?  Then the lights and wires could be in them, and those tubes could perhaps connect up to the above ice habitat some way.

Just a question.  Do you have an alternative?

Last edited by Void (2012-05-01 21:42:01)


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#45 2012-05-02 09:45:56

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

There's ways to run electric wires safely in water.  Your enclose-the-wires-dry inside a tube is one good way.  I kinda like it. 

Concentrating solar thermal is a good way to generate wet saturated steam.   That's all we would need for heat.   Plus,  there's waste heat from the lights. 

Most of the plumbing would be down in the pond,  except for hot lines to and from the solar collector.  Freezing should not be an issue as long as heat is being collected.  Perhaps two collectors for the safety of redundancy. 

I'm really liking this agricultural pond idea.  It looks far easier than any kind of pressure domes or enclosures on the surface.  But limited to "seafood" is not good enough.  The surface enclosure / dry land plant approach needs a pressure solution too. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#46 2012-05-02 19:52:52

Void
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Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

Nice.

I value your decisions.  Here is my response:

Pond-Lake.jpg?t=1336009517

You might notice the curtain, which might allow temperatures as I have speculated, in conjuntion with styraform tiles with concave cavites within which air bubbles might exist, where Houdini would be grateful to have a breath of air.  I might also add that duck weed might be able to live there if given light.

I expect that the pond would turn into a lake.

I have shown a "Dry Box" where you might suppose to grow dry land crops.  I suggest that a humidity 100%< might occur if the cold water of the bottom were used.

I understand that for a rise of 20 DegF, we might expect the humidity to drop from 100% to 50%.

As another feature, it might be expected that a rock formation would resist the grinding force of the glasier.  In that case if the glasier were slow moving then tunnels into soft rock might also yield caves where dry land things might grow.

However, don't let me inhibit solar greenhouses.  I have my own notions, I don't want to stifle the innovation of others.

Please, others, do speculate.  I will respect.

Last edited by Void (2012-05-02 20:07:20)


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#47 2012-05-03 09:54:00

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

How are you guys imbedding graphics in these posts?  I have no idea how to do anything except write text.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#48 2012-05-03 16:45:50

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Solar Enclosure Architecture On Mars

Right click on the graphic object, and select "Properties".
Copy the address Example:

Paste the address between two consructions [***]Address[/***]



But leave out the "*".  *I had to add the to stop it from embeding the graphic.

Submit


Pond-Lake.jpg?t=1336009517

So as not to waste this post:

If a method like this were to work on Mars, then I would also suppose it might work on the Dwarf Planet Ceres, and the Moons of Jupiter, Callisto, and Ganymede, although Ganymede may be too radioactive for people to want to live there unless the radiation belts of Jupiter can be reduced in lethality.

Actually same logic for Europa, and Io, although rigolith is hard to come by with Europa, and Ice is hard to come by with Io.  Perhaps a mass driver exchange program?  But that really pushes the limits.

The poles of our Moon?  Maybe, but you would have to import/Impact a lot of ice, most likely from the Asteroid belt.

Mercury may have vast ice sheets at it's poles in the shadowed craters.  The jury is out on that.  Radar detected something resembling it.

Think of the energy and minerals to be had on Mercury, if you had a decent place to grow food, with abundant volitiles.

Are we going to do graphic's battle now? smile

Last edited by Void (2012-05-03 17:02:42)


Done.

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#49 2012-05-04 06:19:06

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,800
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Re: Solar Enclosure Architecture On Mars

When you're under that much ice, radiation's not a worry. We could create quite nice ice caverns on icy moons, several hundred meters below the ice. No need for regolith when it's too cold for the ice to sublimate anyway...


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#50 2012-05-04 09:25:52

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
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Re: Solar Enclosure Architecture On Mars

Turns out that a drill rig and a steam generator might be really handy to have in space after all!

On really low-gravity places,  your ice cavern will have to be deep enough inside for the basic strength of the ice to hold air pressure.  You won't be able to rely on overburden weight to hold the pressure in.  But,  I see no real problem with that.   

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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