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#1 2007-08-18 20:05:19

SpaceNut
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From: New Hampshire
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Re: Designing the best greenhouse demonstrator for Mars

What would be the best greenhouse demonstrator for Mars?

There are 2 avenues that food production in a greenhouse can take tha I am aware of both of which need proof or evidence that they will work when deployed on mars.

Thou there is a secondary effect of a greenhouse for life support I am not wanting to include this as a part of the demonstrator at this time. Through the production of oxygen as a result of natural plant growth is a plus. Some plants produce more oxygen then others and that maybe taken into account where possible in food growth but as a much later desire.

What would be the guidelines for a demonstrator mission to

1. Creating a Mars first soil greenhouse demonstrator.

or

2. Creating a Mars first hydroponic greenhouse demonstrator.

and what is necessary to show the effectiveness of its abilities.

There of course are a large quantity of sensors, camera's ect...

The greenhouse except for it being inflateble with vary due to the type of growth mechanism media used to prove which would be better for the crews survival.

There is no completely automated system available to incorporate into such a demonstrator but this may not be a show stopper. Taking each step into account from preparing the seeds to there planting will be needed.

Since the available launchers will be a limiting factor and using previous mission to allow for a baseline for entry methods of the capsule both will dictate to some degree the greenhouse parameters to which we must work within.

While the previous landings methods have proven sucessful more mass to mars will be needed in the future and waiting while it may be better to do IMO changes little for the working of the demonstrator for only a few plant types will be need to be view through germination to fruit bearing. Coming up with a first pass estimate on mass of what is needed is required before the final go or no go to start a project of this type to be set into motion anyways. Bt that point the MSL will be on mars and we will know if the sky delivery method will be of benifit to allow for greater masses to the surface if it is required. Of course the final version will be much larger and by time man is going to mars it will be ready.

Some say that the health of the crew could be effected by chromium hexagonal blah blah blah..(risk adversion sensor alarm detecting bull...) and the question is why has it not been detected thus far by the current missions if it is such a problem thus far. How would we test to make sure that the food source will not suffer from this contamination that is so feared?

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#2 2007-08-18 23:29:35

noosfractal
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Re: Designing the best greenhouse demonstrator for Mars

These Mars Deployable Greenhouse designs submitted for NASA's MarsPort 2002 competition might be a good starting point ...

http://projects.olin.edu/marsport/

http://www.mae.cornell.edu/europa/Final … 002pdr.doc


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#3 2007-08-21 21:04:53

SpaceNut
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Re: Designing the best greenhouse demonstrator for Mars

Thanks for the links they were very usefull.

I am learning alot about greenhouses in general....

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#4 2007-08-22 06:35:14

noosfractal
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Re: Designing the best greenhouse demonstrator for Mars

If they are well done, student group reports can help you get the lay of the land quite quickly.  You have to read them with a skeptical eye though - kind of like Wikipedia.


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#5 2015-09-13 20:38:35

SpaceNut
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Re: Designing the best greenhouse demonstrator for Mars

The risks of Mars

Human missions to Mars carry significant risks, but so do activities on Earth. As I meantioned in the first post risk adversion is written about in the article by by Frank Stratford.

We can be overly cautious and even go overboard to keep safe that we will never go but then again we could be on the other extreem of the scale taking to much risk and not be prepared at all for what awaits us if we ever do go to mars.

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#6 2015-09-17 13:17:42

Void
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Re: Designing the best greenhouse demonstrator for Mars

I was intimidated to even try to give an answer to this, and perhaps I needed to be, but oh well, this is what I would be interested in trying.

If I understand, this greenhouse should be an inflatable device, and is intended to provide an early on site food source for the first settlers.
So, it is not likely to be manufactured on Mars, but sent from Earth.

Mass will be an issue, and pressure retaining transparent glazes are as far as I am concerned will be amount the most difficult items to have, other than space suits and your return to orbit assets.

Therefore, I suggest that if you have a transparent bubble, you might want to reflect additional sunlight into it using recycled metal or other materials, from your landers, if possible.  Making solar reflectors to deflect additional sunlight into it.  Maybe that could be done.

Of course this will be limited by the challenge it might present to the transparent material itself, and also there are issues with how much light plants need.  I think I have a plan for that.  Overheating may be a problem, so something has to be done about that, and I have ideas for that but lets set that aside for now.

Grow Food Vertically in Windows and Walls of your Home with Hydroponic Gardening

https://www.youtube.com/watch?v=jZCL3H9XpU4
Growing Spirulina:
http://www.spirulinaacademy.com/grow-yo … spirulina/
Food value of Spirulina:
http://www.livescience.com/48853-spirul … facts.html

Supposing that you could amplify enhance the amount of photons going into your greenhouse, certain plants only need so much.
However from the first link, I propose that vertical cylinders that rotate could also have "Wall Gardens" on their outer surface.
So the notion is to rotate them, so that the plants experience a solar flux that is like a partly cloudy day on Earth.  However full sunshine might be more than 10,000 Lumens?  (Earth full sunshine), that being limited by the tolerance of the plants.

The spacing of the cylinders would be up to the planner. Possibly cylinders would occupy almost all of the space,  and each plant would be rotated to the full sunshine of the outer wall, or the cylinders could have more space between them, and so some could be inside of the others.

As for Spirulina, I suggest that it could be in stationary, "Wall Gardens" where desired.  It is possible that sunshine passing through such spirulina wall gardens would still be sufficient for the plants which would be in the cylinder wall gardens.

Of course this approach is technically more challenging.  It requires motors, and robotics to a degree, but it is worth thinking about I believe.

Again the wall Spirulina tanks (Not on the cylinders) would also double as a cooling system.  It is even possible that this system could  be used to generate electricity, but that would  be a further challenge.

Anyway, there you are.  If you are like me, you usually will like it if you get some kind of reasonable attempt to offer solutions to the problems you present.

Last edited by Void (2015-09-17 13:29:50)


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#7 2015-09-17 15:42:16

RobertDyck
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Re: Designing the best greenhouse demonstrator for Mars

Ok, my suggestion. This is a demonstrator for Earth, right? But as close as possible to Mars conditions?

I would start with a real inflatable. A real greenhouse for Mars would use PolyChloroTriFluoroEthylene (PCTFE). That is sold by Honeywell under the names Clarus or Aclar. Clarus is intended for aerospace and military use, while Aclar is primarily moisture barrier for blister packs for pills (pharmaceuticals). The fact Clarus requires a custom order while Aclar has standard off-the-shelf products, I suspect Aclar is much more affordable. For Mars you would use Clarus with vacuum deposition of metal to create a spectrally selective coating. The same coating used for spacesuit helmets, or windows of spacecraft or ISS. However, for your Earth demonstrator I would suggest just simply getting a roll of Aclar. Ideal would be 2 mil thick film. That's the thinnest that can be relied upon for strength. Heat seal edges of sheets together to form the greenhouse.

Aclar

The shape can be flattened with hold-down straps. For Mars I have argued for hight to width ratio of 1:2. The reason is on Mars flat mirrors outside the greenhouse would reflect sunlight through the sides, doubling illumination. But on Earth we don't need the mirrors. These straps would be held with tent pegs, the kind for large event tents.

This greenhouse would actually be pressurized. On Mars it would not be pressurized to 1 atmosphere, I have argued for between 5.0 and 8.433 psi. But this analogue would require just enough pressure to hold up the "roof" of the inflatable greenhouse, and make operation of the airlock real. The fan for an inflatable building should be sufficient to inflate the airlock, you shouldn't require a compressor.

I argue for soil agriculture. Use "JSC Mars 1" as your regolith simulant. That's from NASA, volcanic soil collected from Hawaii. It's very similar to Mars. I could get into fine detail exactly how accurate, but good enough. I would start remediation for planting by soaking the soil with soda water. And by that I mean carbonated water, no sugar or other additives. This is carbonic acid, a mild acid to reduce pH, and the first step to add carbon to the soil. On Mars you would make soda by pressurizing Mars atmosphere in a container of clean water. Leave it for a few hours, the CO2 will dissolve.

I have argued for ambient light agriculture, so if this is setup outside, we don't need artificial light. But if it's setup in a cold location, then heat control will be an issue. I'm in Canada, we have actual winter. I lived in Miami Florida for 10 months, I mentioned to one co-worker that I escaped winter that year. She said "This is winter." Um, no, Miami doesn't have real winter. But a greenhouse on Mars should have 2 layers of film with a gap between them. The gap doesn't have to be big, just the same as between panes of a double pane window. This would be accomplished with pressure. The gap would have more pressure than outside, but less pressure than greenhouse interior. This means both layers need hold-down straps. So the outer layer will have a point where the hold-down strap for the inner layer passes through. That has to be sealed. So a section of strap or cord has to be non-woven to be air-tight. That section can be connected to a woven strap inside via a metal ring, and to a rope outside via another ring. The rope would go to the tent peg.

It would be an interesting exercise to calculate temperature for this greenhouse. Could you get a sheet of Aclar coated with the same coating as Heat Mirror brand window film? That uses silver oxide, developed from NASA's spectrally selective coating. NASA's actual coating has silver oxide, but also gold and nickel. Silver oxide alone will reflect IR and those frequencies (colours) of UV that get through Earth's atmosphere. The other metals are needed for the more harsh environment of space. Or could adhesive film be applied to Aclar film?

Just one example: High Heat Rejection Reflective Window Film Silver

And if you build the greenhouse with two layers, fill the gap with argon gas. And install pressure sensors outside, in the gap, and inside the greenhouse. A drop in pressure in the gap would mean a leak in the outer film. An increase in pressure would detect a leak of the inner film.

And how would you treat the floor? How would you design an insulated floor that will keep the greenhouse warm in winter, yet you can walk on?

Calculating heat flow in winter would be an interesting undergraduate engineering exercise.

And advanced technique would include a "gutter" on the inside of the plastic film wall. As light as possible, possibly a firm plastic film shaped as a "gutter" or "eavestrough" to catch condensation. It doesn't have to be as large as a gutter (American term) or eavestrough (Canadian term) for a house. Probably 1 cm wide would be enough. Water collected would be routed to a hose, stuck into a large container. The reason is "grey water" from sewage treatment could be used to water the plants. After water goes through the plants and transpires through leaves, that humidity is very clean. Condensation would be much more tasty than the best filtration system NASA has come up with.

Last edited by RobertDyck (2015-09-17 20:11:31)

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#8 2015-09-17 19:10:54

SpaceNut
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Re: Designing the best greenhouse demonstrator for Mars

Nice post on the materials to try to prototype the demonstrator with. Something simular to the reflective coating might be this product...Titanium Heat Control Window Film

The Gila 4 ft. x 15 ft. Titanium Heat Control Window Film will allow you to reflect up to 72% of the sun's heat to keep your home cool and to reduce summer cooling costs. This film blocks up to 99% of UV rays to prevent your furniture and decorations from fading. The light tint won't lower the quality of your view.

•Reflects up to 72% of the sun's heat to provide a cool interior and low summer cooling costs
•Light tint won't block your view
•Quick and easy to install
•Blocks up to 99% of UV rays to reduce fading

I hope others will try there hand to do so as well .....

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#9 2015-09-18 17:31:59

RobertDyck
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Re: Designing the best greenhouse demonstrator for Mars

A simple kitchen appliance to make a bottle of carbonated water. Again, this is to treat soil as the first step to create arable soil for agriculture.
SodaStream Beverage Station
I prefer "Play White", simply because it's cheap. We won't use it often enough to justify an expensive unit. It includes a 1L bottle for the beverage, and a canister of pressurized CO2 with enough to carbonate 60 bottles. Just add water. The unit also comes with some "complimentary" flavour packs to make their soda pop.
play-plastic-white.jpg

I linked the Canadian site, but they are in the US too.
SodaStream USA

There are other brands of sparkling water maker, I just mentioned the one I saw in local stores.
KitchenAid
The Sweethome
Genesis

Cook's Illustrated review of home seltzer makers

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#10 2015-09-18 19:34:32

Excelsior
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Posts: 120

Re: Designing the best greenhouse demonstrator for Mars

With advancements in aquaponic and microponic systems, I think we can greatly simplify off world agricultural systems. LED's are cheap and effective sources of light. There is plenty of CO2 readily available to enrich the atmosphere. Conventional hydroponic systems require complex nutrient solutions, the ingredients of which would have to be found, likely refined, and mixed. Aquaponics uses fish effluent as a nutrient solution, recycling the water back to the fish. Other small animals contribute to a wider ecosystem, of which the astronauts are but a part.

The question is, can we get the fish to their destinations? It would seem that simulated gravity is essential.


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#11 2015-09-18 21:42:17

SpaceNut
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Re: Designing the best greenhouse demonstrator for Mars

The gravity would not allow for hydroponic as the water would want to got into a vapor of mist state unless we are at a full atmosphere in the greenhouse on mars and we are looking at something less.

mars soil simulant http://chapters.marssociety.org/or/cemss/marsoil.html JSC Mars-1A is a palagonite tephra collected from the slopes of the Pu’u Nene cinder cone on the Island of Hawaii. or from http://www.orbitec.com/store/simulant.html The chemical composition is compared to that of a typical Mars surface sample analyzed at the Viking lander 1 site. http://isru.msfc.nasa.gov/lib/Documents … _M2003.pdf

http://www.lpi.usra.edu/meetings/lpsc2007/pdf/2005.pdf
http://www.academia.edu/4499376/Mojave_ … l_Simulant

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#12 2015-09-18 23:14:00

Void
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Re: Designing the best greenhouse demonstrator for Mars

I'm sorry, feeling more than a little annoyed.

You asked for this:

1. Creating a Mars first soil greenhouse demonstrator.

or

2. Creating a Mars first hydroponic greenhouse demonstrator.

and what is necessary to show the effectiveness of its abilities.

There of course are a large quantity of sensors, camera's ect...

We both gave you something along what you asked for.

Rather than to participate in some ego fencing, I would prefer consider that I posted to your lonely little thread, as a favor to you.  I gave it my best effort for your sake.

As a matter of fact I happen to like Roberts work as well.

But you asked for hydroponics on Mars as well:

http://www.nasa.gov/missions/science/biofarming.html

https://life2mars.wordpress.com/the-basics/hydroponics/

•Soilless gardening offers many advantages to the gardener. There are no weeds to remove, and soil-borne pests and diseases are minimized, if not eliminated.
•If grown properly, hydroponic plants are also healthier and more vigorous.
•There is the advantage that the entire system may be automated with a timer.

So, I am having trouble seeing why hydroponics are ruled out.

OK, automation, possible with soil gardens as well.

However the hydroponic method I suggested, really could be very highly automated.  For instance where I said cylinder, (Actually, a hoop with hydroponic pouches hanging down, with drip pans below.  Each cylinder turning slowly, a robot in the center of a collection of cylinders, perhaps able to monitor and work with the plants with minimum complexity.  Perhaps just a robot arm with sensory equipment.

Photon concentration, no comments from anyone, rather rude.

Alright the saying of vapor/mist at low pressures.  Hmm... What if I wanted that?  For instance how about using the natural cold of the Martian night times to cool a tank of water, and bubbling humid air through that to condense it.  Two purposes served.  Evaporative cooling, and condensation of water, which may be recycled for use.

Now for the hydroponic solutions.  Well, if you are working with soil, yes, at first after you have detoxed the soil, perhaps you will have natural nutrients, but they will deplete unless you recycle human waste materials, unless you know of some way to extract nutrients from more soil, but in the end it is the same, you have to fertilize.

Summary,  Mars has low light conditions in the first place.  Then having a greenhouse will attenuate that.  So adding light with exterior reflectors is not an idea to dismiss rudely.  Further, I did suggest methods to make the most use of light that does get into the greenhouse, as it will have taken great effort to get it into a pressurized greenhouse in the first place.  Wasting any of it without consideration would be silly.  I also gave you a high protein source, that being Spirulina.
http://www.antioxidants-for-health-and- … ulina.html
And, evaporation can actually be used to a benefit.  I do not think that with plentiful supply of nutrient water that you could ever not be able to water the whole length of a "Wall" hydroponic garden.
And, since the spirulina would be in plastic pouches distributed as desired (The amount of shade you wanted) along the inside of the walls, you also have a method to extract heat (Cool the greenhouse as well), and at night from the tank(s) add heat to the greenhouse with water circulation.  Perhaps there are better methods, but it is a possibility.
Robert gave specifics on a greenhouse, fine, I like it.

Would I wrestle in the mud with him hydroponics vs soil?  No!  I just took a side of the case and did what you asked.

As I understood your request, this greenhouse was to come "Out of the box", and start growing food for the newly arrived persons.  I endeavored to make the size of the greenhouse as small as possible, to reduce weight.

As for Roberts plans, yes, as greenhouses are to built by Martians for Martians, more and more from local materials, by all means, a soil garden.  That will be pleasing to humans as well.

Oh and by the way now that I got that out of my system, some long time ago I did an experiment with plastic milk bottles, and Styrofoam beads, and Tomatoes.  It worked just fine.  Water it put some fertilizer in it.  Tomatoes, no problem.

Point being that in that case, you can hang those vertically, against the transparent windows/walls, and get the most sunlight, and you minimize the weight.

Hope I haven't dented your day too much.  Felt I should put some balance back into this.  If you feel negative about this, let me know.  There will be not point in us just annoying each other.  I can certainly find better things to do.

Last edited by Void (2015-09-18 23:24:14)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#13 2015-09-19 00:33:06

RobertDyck
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Re: Designing the best greenhouse demonstrator for Mars

I have also tried to avoid contention. I have argued in the past that a greenhouse is the only life support system that isn't dependant on power. A Mars habitat has to provide oxygen and water. It will have multiple life support systems, with mix-and-match components. So there isn't just one or two backups, there are multiple layers of backup. But they all depend on power, so power production becomes a single point of failure. Actually, Mars Direct has a nuclear reactor for the ERV, and solar panels for the hab. Solar panels track the Sun while in transit from Earth, then fold up for atmospheric entry. On Mars astronauts will remove them from the hab, deploy them outside with cables back to the hab. If one fails, a power cable can be run to the other. But a greenhouse can provide life support with no power what so ever. A small greenhouse isn't all that stable; Biosphere 2 found a perfectly bio balance extremely difficult and they had a huge greenhouse. But a small one will work when mechanical/chemical life support can back it up. And the greenhouse can provide life support for months if necessary, during major repair of the power plant. For this reason I prefer 100% ambient light. With artificial light only used during dust storms. With solar compromised by the dust storm, and the greenhouse dependant on power, that makes the reactor again a single point of failure. I'm not comfortable with that, but don't see a way around it.

However, we don't need to burry the greenhouse. Plants are more hardy vs radiation than we are. Radiation on Mars is low enough that we don't have to worry about it. For plants.

But soil vs hydroponics? I'm not sure. Both have merit. I have pointed out before that producing hydroponic solutions is involved, which is why I lean toward soil. But let's face it, soil has issues too. Mars soil is known to have perchlorates. Can the be controlled, or will they kill crops? Superoxides will decompose as soon as soil is soaked in water. I have studied Mars soil in detail from data published by Mars Sojourner. Data from rovers are more difficult because there's so much, and it's more difficult to access. But what I've seen indicates no nitrogen what so ever within detection threshold of instruments. For Sojourner that meant less than 0.1% by weight. And soil carbon is difficult to assess because it's in the margin of error for the instruments. Mars soil has too much iron, and potassium is too low. There should be deposits of potassium salts in dried up ocean beds. Where? One book by Robert Zubrin suggests potassium deposits along the shore line. But it may be where water finally pooled and evaporated, so low points of the ocean bed. We really don't know yet. Mars soil may be just too salty. Especially at the bottom of an ocean bed, such as Elysium Planetia. So exactly the place you want for water ice and potassium could have too much salt in the soil. Washing soil could remove salt, but that could remove necessary nutrients as well.

But perchlorates are a major worry. Phoenix found perchlorates in soil. It acts as antifreeze, aiding liquid water on Mars. But perchlorates are quite toxic. And accumulation in vegetables can be harmful to humans. We can hope that perchlorate are not everywhere on Mars. But Curiosity is actually on the shore line of Elysium Planetia. And Curiosity found calcium perchlorate in soil. Oops!

The way to deal with lack of nitrogen in soil is to make ammonium nitrate fertilizer. I could explain how to make it from nothing but air and water and electricity and equipment you could get from a hardware store. But since the Oklahoma bombing, it's not a good idea to post that. But this means making a chemical. Hydroponics needs chemicals for its nutrient solutions. So the need for chemical fertilizer for soil agriculture at least partially counters its benefits.

Simply shovelling soil into plastic trays, adding water and planting seeds, sounds like a very simple way to grow crops. And I keep trying to find ways to make it that simple. But truth is there are real issues. And those issues justify hydroponics. I will still work to make a soil greenhouse on Mars workable, but let's not belittle alternatives.

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#14 2015-09-19 22:35:05

SpaceNut
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From: New Hampshire
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Re: Designing the best greenhouse demonstrator for Mars

Void, sorry that I did not reply to your post Very well....one of the hydroponic links I did have but had not reviewed it for sometime....I do feel that hydroponic will be the best once we can deliver the needed system but we are having a hard time delivering a crew at this point.

Problem for Mars....lack of space suits....
64160main_hydroponic_82.jpg

Water turning to vapor condenses at temperatiures that would freeze the plants.

If we need a soil substitute, special trays to hold it contained, then pumps for moving the water to the plants and more.... then we are over budget for the first greenhouse on Mars.

Current level of space plant growth onboard the ISS which while hydroponic is still experimental...

http://www.nasa.gov/mission_pages/stati … eggie.html

The Vegetable Production System (Veggie) provides a means to supply crews with a continuous source of fresh food and a tool for relaxation and recreation. Veggie will study crop productivity, air and water revitalization with reduced logistical and operational resources compared to other plant growth systems.

Veggie weighs 7.2 kg and requires 115 Watts of power. While stowed Veggie requires 0.02 m3 and deployed it requires 0.11 m3 of space. Veggie has a growing area of 0.16 m2 with a maximum growth height of 45 cm.(The internal growing area is 11.5 inches wide by 14.5 inches deep,) The hardware is cooled with cabin or avionics air. The Veggie light sources are red (640 nm) 300 micromole/m2/s, green (540 nm) 30 micromole/m2/s and blue (440 nm) 50 micromole/m2

http://www.nasa.gov/content/veggie-plan … ce-station

A root mat and six plant "pillows," each containing 'Outredgeous' red romaine lettuce seeds, were inserted into the chamber. The pillows received about 100 milliliters of water each to initiate plant growth. The clear, pleated bellows surrounding Veggie were expanded and attached to the top of the unit.

Inside each plant pillow is a growth media that includes controlled release fertilizer and a type of calcined clay used on baseball fields. This clay increases aeration and helps the growth of plants.

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#15 2015-09-20 08:20:30

RobertDyck
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Re: Designing the best greenhouse demonstrator for Mars

Calcium perchlorate will react with most metals, including aluminum powder or iron powder. After all, ammonium perchlorate and aluminum powder is the primary fuel for Shuttle SRBs. But treating soil requires some sort of liquid. Would hydrogen peroxide react with calcium perchlorate? I expect hydrogen peroxide would become water, releasing hydrogen. And the hydrogen would react with oxygen from perchlorate, leaving more water and calcium chloride salt. Would that work?

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#16 2015-09-20 08:59:36

Tom Kalbfus
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Re: Designing the best greenhouse demonstrator for Mars

what of we built a dome within a dome, the outer dome is rigid, its glass is tinted to let in only as much sunlight as Mars gets, its refrigerated to make the interior as cold as Mars, fill the outer dome with a simulated Mars atmosphere, then inside inflate an inner dome which will be the greenhouse.

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#17 2015-09-20 09:51:20

Terraformer
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Re: Designing the best greenhouse demonstrator for Mars

Huh? Hydrogen peroxide releases oxygen, not hydrogen.

Is there any way of leaching the calcium perchlorate out?


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#18 2015-09-20 10:15:17

RobertDyck
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Re: Designing the best greenhouse demonstrator for Mars

Oops. Uh, yea. So here is a paper about thermal decomposition.
THERMAL DECOMPOSITION OF CALCIUM PERCHLORATE/IRON-MINERAL MIXTURES: IMPLICATIONS OF THE EVOLVED OXYGEN FROM THE ROCKNEST EOLIAN DEPOSIT IN GALE CRATER, MARS.
The paper talks of oxygen released at +300°C to +500°C. Lab tests showed Ca2(ClO4)·4H2O bound with a mineral called fayalite released oxygen up to +510°C. Tapered ends of the graph didn't completely flatten until +520°C. So we bake soil before adding seltzer.

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#19 2015-09-20 19:58:44

SpaceNut
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Re: Designing the best greenhouse demonstrator for Mars

Perchlorates are the salts derived from perchloric acid ClO4 and there are lots of them.

  • Chlorine oxidation state  −1  +1  +3  +5  +7
    Name               chloride  hypochlorite  chlorite  chlorate  perchlorate
    Formula            Cl−       ClO−          ClO2−     ClO3−     ClO4−

Most perchlorates are colorless solids that are soluble in water, except for potassium perchlorate, which has the lowest solubility of any alkali metal perchlorate, ammonium perchlorate (NH4ClO4), perchloric acid (HClO4), potassium perchlorate (KClO4), sodium perchlorate (NaClO4), Magnesium perchlorate Mg(ClO 4). Lead(II) Perchlorate...... 

Ammonium perchlorate composite propellant as a component of solid rocket fuel.Niche uses include Lithium perchlorate, which decomposes exothermically to produce oxygen, useful in oxygen "candles"

Nuetralizing these will take lots of working of the specifics that are needed.
3 KClO4(Potassium perchlorate) + C6H12O6(glucose) → 6 H2O + 6 CO2 + 3 KCl

Perchlorate Salts and Water on Mars: An Overview of Recent Work

OXIDATION OF CHLORIDE TO PERCHLORATE UNDER AMBIENT MARS CONDITIONS

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#20 2015-09-21 06:35:44

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: Designing the best greenhouse demonstrator for Mars

Terraformer wrote:

Huh? Hydrogen peroxide releases oxygen, not hydrogen.

Is there any way of leaching the calcium perchlorate out?

What you need is hydrochloric acid and zinc, I did that experiment and it released hydrogen because the chlorine reacts with the zinc and releases the hydrogen. I guess that means you shouldn't eat zinc, as there is hydrochloric acid in your stomach, and belching hydrogen would be a bad idea!

Last edited by Tom Kalbfus (2015-09-21 06:37:49)

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#21 2015-09-21 20:24:12

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 18,322

Re: Designing the best greenhouse demonstrator for Mars

As we talked about the cold and being brittle I began the search for topics containing info on the floor. As we would not have a flat smooth section of land for it to be set up on and it must be able to take the cold into account....

Aerogel - don't build - your greenhouse w/o it

Mars first crew greenhouse

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#22 2015-09-21 20:36:37

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,898
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Re: Designing the best greenhouse demonstrator for Mars

I see an old post I made in "Mars first crew greenhouse" uses tex for superscripts. This forum doesn't support tex anymore. I could replace the code for "^2" with the ASCII character "²". ASCII has ² and ³ and ¹ but not other digits, and no subscripts. Should I edit the old posts?

Last edited by RobertDyck (2015-09-21 20:37:37)

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#23 2015-09-21 20:41:07

RobertDyck
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From: Winnipeg, Canada
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Posts: 5,898
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Re: Designing the best greenhouse demonstrator for Mars

Tom, treatment must be relatively simple, without requiring a lot of chemicals from Earth, and most importantly must leave soil suitable to grow food crops. Human nutrition requires a certain amount of zinc, but would it poison soil?

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#24 2015-09-22 19:40:34

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 18,322

Re: Designing the best greenhouse demonstrator for Mars

Void I have no idea what Spirulina, so me being me I did look it up and while all the literature sound great its not something that is serve on the dinner table. A simple vegetable as blue green algae Spirulina grows so fast, it is harvested every 3 days.  http://www.superfoodsforlife.com/page/103407

http://ag.arizona.edu/hydroponictomatoes/nutritio.htm

There are sixteen elements which are generally considered to be essential for good plant growth. The macro elements are those required in "high" concentrations: Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Sulfur (S), and Magnesium (Mg). Carbon must be supplied to the plant as carbon dioxide gas (CO2). In a small operation or one with large amounts of fresh air movement, additional CO2 may not be required.

The micro elements are also essential for growth, but required in smaller concentrations. There is still some disagreement, but generally the micro elements are thought to be: Iron (Fe), Chlorine (Cl), Manganese (Mn), Boron (B), Zinc (Zn), Copper (Cu), and Molybdenum (Mo). Certain plant species may need others for good growth: Silica (Si), Aluminum (Al), Cobalt (Co), Vanadium (V), and Selenium (Se).

  • Table 1. Fertilizer salts (adapted from Jensen and Malter, 1995)

    Fertilizer Salts element supplied grams of fertilizer needed per 1000 liters of water to provide 1 mg/l (ppm) of the nutrient specified
    Boric Acid [H3BO3] B 5.64
    Calcium nitrate [Ca(NO3)2·4H2O] (15.5-0-0) N 6.45   Ca 4.70
    Cupric chloride [CuCl2·2H2O] Cu 2.68
    Copper sulfate [Cu(SO4)·5H2O] Cu 3.91
    Chelated iron (9%) Fe 11.10
    Ferrous sulfate [FeSO4] Fe 5.54
    Magnesium sulfate [MgSO4·7H2O] (Epsom salts) Mg 10.75
    Manganese chloride [MnCl2·4H2O] Mn 3.60
    Manganese sulfate [MnSO4·4H2O] Mn 4.05
    Molybdenum trioxide [MoO3] Mo 1.50
    Monopotassium phosphate [KH2PO4] (0-22.5-28) K 3.53   P 4.45
    Potassium chloride [KCl] (0-0-49.8) K 2.05
    Potassium nitrate [KNO3] (13.75-0-36.9) N 7.30   K 2.70
    Potassium sulfate [K2SO4] (0-0-43.3) K 2.50
    Zinc sulfate [ZnSO4·7H2O] Zn 4.42

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#25 2015-10-18 08:39:30

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 18,322

Re: Designing the best greenhouse demonstrator for Mars

Here's what happens when you grow sunflowers in outer space

13544-v1-490x_0.JPG?itok=d7TaYnEX

Pettit’s foray into gardening aboard the ISS was an unofficial project — an attempt to make his residence above the clouds a little homier with the equivalent of a potted plant in the kitchen window. He had no resources from the station. No designated electricity, no fans, no computer or data transfer control. It was supposed to be a simple splash of green in a sea of machinery. The plants grown on Pettit’s ISS “windowsill,” however, are giving scientists a lot of information about basic plant biology. They are intrinsically lazy and, they only put out as much effort as the environment requires,” Pettit says. Plus, as he found out, plants grown in zero gravity end up looking really unusual.

Experiments in the Haughton Canadian High Arctic are working on the concept of "activating" plants. This would allow the potted seeds to be shipped to Mars ahead of time, and "activate" just as astronauts are about to land on Mars. "The plants would be growing already when they arrive,” Driscoll says.

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