Horizontal Farming on Mars

tahanson43206 · 2023-10-30 07:52:25

This topic is offered for NewMars members who might wish to focus on horizontal Farming as contrasted with vertical farming.

We have topics about components of horizontal Farming, but this topic is intended for review by an investor planning a facility on Mars.

That investor is going to be supplying produce to the market there, and the question to be addressed is the potential advantage of horizontal Farming as compared to vertical farming.

There is a third way of farming, which is neither horizontal nor vertical...

For that category I will set up a new topic.

Here are the topics of record on 2023/10/30 for farming...

Vertical Farming by tahanson43206
Life support systems 10 Today 07:28:47 by Void
Indoor farming update by louis [ 1 2 3 … 6 ]
Human missions 149 2023-09-26 18:52:42 by Mars_B4_Moon
Robot Farming. by Void [ 1 2 ]
Science, Technology, and Astronomy 35 2023-08-17 04:06:14 by Mars_B4_Moon
Horizontal Wind Turbine farms - management - Good Neighbor Policy by tahanson43206
Human missions 4 2023-04-04 19:38:45 by SpaceNut
Farm Self Sufficient using Natural Fuel from Solar/Wind Power by tahanson43206
Science, Technology, and Astronomy 8 2023-01-29 18:46:26 by SpaceNut
Sticky: How to Prepare Water for Use: Drinking - House - Farm - Manufacturing by tahanson43206 [ 1 2 ]
Science, Technology, and Astronomy 46 2022-08-16 18:02:55 by SpaceNut
Dutch Rebellion in Netherlands, what if the Farmers of Mars Protest? by Mars_B4_Moon

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RobertDyck · 2023-10-30 17:38:10

I have argued for ambient light farming on Mars. We are talking about a planet that has no breathable atmosphere, multiple backups for life support are necessary. All means of generating oxygen to breathe have a single point of failure: power. All but one: greenhouses. If you make all greenhouses dependent on artificial light, they they have the same single point of failure. To call that unsafe is an understatement.

Some people are afraid of radiation. If you have an irrational fear of radiation, then you shouldn't go into space. Radiation is something that has to be respected, but work with it, don't hide under the bed. What do I mean? Overall the surface of Mars has half the radiation of the International Space Station. In detail: 90% of heavy ion galactic cosmic radiation (GCR) is blocked by the atmosphere of Mars at a high altitude plateau such as Meridiani Planum. That's where the rover Opportunity landed. At the bottom of the dried sea basin, altitude is lower which means more atmosphere overhead, resulting in up to 98% of heavy ion GCR blocked. Plants are more hardy vs radiation than humans or any mammal. They can handle it.

I argue for ambient light greenhouses. That means glass roof and walls like a greenhouse on Earth. Obviously a greenhouse on Mars must be pressurized. For a science mission, I have suggested an inflatable greenhouse. I took the inflatable greenhouse design from a paper written by Dr. Penelope Boston in "The Case for Mars" papers, before the Mars Society was founded. It's a great idea! I suggest PCTFE film because it's highly durable to UV, can withstand the cold of Mars, the most impermeable to water of any polymer, and highly impermeable to oxygen. There are other polymers more impermeable to oxygen, but they become brittle in the cold of Mars night. You don't want your polymer film cracking and releasing pressure. The polymer requires a spectrally selective coating to block UV because Mars has no ozone layer. Technically it does have one, but it's so thin that it's not effective. The traditional coating is nickel, gold, and silver oxide. Only silver is oxidized. The silver oxide primarily blocks IR. Windows for Apollo spacecraft, Skylab, Shuttle, ISS, spacesuit helmet visors, are all coated. You must protect human eyes from UV-C because it can cause cataracts. Plants get damaged by UV-C as well, and plants get sunburn from UV-B. These metals are vacuum deposited. Any vacuum deposited metal on polymer film will clog pores making it even more impermeable.

For a greenhouse manufactured on Mars from in-situ materials, I suggest glass. Tempered glass specifically, which is just a heat treatment for normal window glass. Tempered glass is harder than grains of sand and dust of Mars dust storms. Polymer film or normal glass would be "crazed", which means many tiny scratches making the window no longer transparent. A crazed window is translucent, meaning light can get through, but you can't see through. Tempered glass is harder so a dust storm would not scratch or craze windows.

Many have argued for hydroponics. I have incorporated hydroponics and aquaponics in many designs. For a settlement on Mars, this has a problem: nutrient solution. Hydroponics requires nutrient solution, fertilizer dissolved in water. If your source of those nutrients is Mars dirt, then that requires industrial processing. Processing Mars dirt to make arable soil would require less processing. Let plant roots extract nutrients directly from soil themselves. Yes, Mars dirt has perchlorates, which would get into any vegetables grown in soil with perchlorates, and that makes the vegetables toxic. However, there are papers published of an enzyme that breaks down perchlorates into salt and oxygen. Certain bacteria use perchlorates as food, breaking them down into salt and oxygen and extracting energy by doing so. The enzyme was isolated from those bacteria. The enzyme alone acts much faster than bacteria. Soil must also have some of the salt washed out. That runs the risk of washing out nutrients, so you have to be careful. Superoxides are released simply by soaking dirt in water. Mars dirt has no nitrogen, no organics, and insufficient potassium. But there's a simple chemical process to make nitrogen fertilizer. Just extract nitrogen from Mars atmosphere, react with oxygen and water in a known reaction, the result is ammonium nitrate fertilizer. Yes, I know how to make it with nothing but air, water, electricity, and equipment you can get at a hardware store. No, I won't post it. That fertilizer has been regulated since the Oklahoma bombing.

According to agriculture science, something cannot be called soil unless it contains organic matter. Mars does not have organic matter. When there's no organic matter, it's called dirt.

Potassium can either be concentrated by processing lots of Mars dirt, or preferably find a potash deposit. On Earth when a salt sea completely dries up, it leaves deep layers of salt. Those salt deposits become buried over time. Millions of years ago the Mediterranean dried up when tectonic plate movement closed the Straits of Gibraltar. Result was deep deposits of salt beneath what is now the Mediterranean. Also millions of years ago, there was a salt sea where the Great Lakes of North America are. When that dried up, it also left deep salt deposits. Even more millions of years ago, North America had an inland sea: more salt deposits. In all cases, salt deposited in layers: sodium chloride, potassium chloride, calcium chloride, etc. Potash is one of those layers. Most salt in North America and Europe comes from mining those deposits. The dried up ocean of Mars will have similar salt deposits, we just have to find them.

Horizontal farming produces one layer of growing plants. Light is from sunlight, so there's only so much. Light in Mars orbit is 47% as intense as Earth orbit, however Mars has a thinner atmosphere so more of that light reaches the surface. Mars surface has 59% as intense sunlight as Earth. That's for the same latitude, same time of day, when Earth has dry air, no clouds, no humidity, and absolutely no dust or aerosols. Most places on Earth are not as dry as the Atacama Desert. The "Frozen Pack Ice" of Mars it at 5° North Latitude. That will have as much sunlight as 54° latitude on Earth, on a perfectly dry day with zero aerosols, clouds or humidity. Thompson Manitoba is 55°. The Pas Manitoba is 53.8°. There's not much agriculture up there. But Edmonton, Alberta is 53.55°, and Prince Albert, Saskatchewan is 53.2°. There is agriculture around those cities. The Manitoba cities don't have good soil.
Reference: Sunlight on Mars - Is There Enough Light on Mars to Grow Tomatoes?

I have suggested growing crops that require full sun in a greenhouse with mirrors. Build a long narrow greenhouse, oriented with the long end perfectly east-west. Width exactly twice height. Place flat mirrors along the long sides of the greenhouse, with the bottom of the mirror at the same level as the grow beds (soil trays) of the greenhouse, and the top of the mirror level with the top of roof of the greenhouse. Tilt mirrors 45° from horizontal at the spring and autumn equinox. This will reflect from the sides an equal amount of light as direct illumination through the greenhouse roof. As Mars goes through seasons, angle of the mirrors will have to be adjusted: adjust tilt 1° every 14 Mars solar days. For a greenhouse north of the equator, increase mirror angle on the north side, decrease on the south side, between summer solstice and winter solstice. After winter solstice do the reverse. This is why I said greenhouse should be twice as wide as high; the mirrors will provide as much light as direct illumination. This will double light for crops, allowing crops that require "full sun" to thrive: eg, corn, wheat, all grains, etc.

For crops that require shade (most vegetables), no mirrors are required. Build the greenhouse as a low dome. A circle has minimum circumference per unit area, so this will minimize surface area of the enclosure while maximizing land area for growing crops.

I mentioned aquaponics. That's integration of aquaculture (growing fish in a tank) with hydroponics. This is only effective if you grow enough fish. Parts of the plants that humans don't eat (leaves, stems, etc) are fed to the fish. Fish poop is used as fertilizer for hydroponics. Human urine can be used as fertilizer for hydroponics, but it requires a lot of processing. An electrolysis tank removes most salt. Urea, uric acid, and creatinine are the yellow stinky stuff in human urine. Urea chemical formula is CO(NH2)2. Reacting that with oxygen by dissolving in water and aerating with various methods (eg fountain), will break that down. Oxygen from air binds with CO to form CO2. Hydrogen from water binds to NH2 to become NH3 (ammonia). Oxygen from water is released. Net releases as much oxygen from water as is consumed from air, so no net consumption of oxygen, but oxygen is required as a gas for the reaction to work. Sunlight may also be required as an energy source. However, breaking down uric acid and creatinine are more complicated. The most effective way of doing so is via bacteria. That takes months.

When ammonia dissolves in water it becomes ammonium (NH4+). Most food crops require nitrate (NO3-). Bacteria break down ammonia in several steps, becoming nitrite (NO2-), then finally nitrate.

I mentioned life support backup. Plants transpire water through their leaves, becoming humidity. That humidity will condense on cold windows. A collection trough at the bottom of each window can collect that water. Plants can be watered with grey water, but water collected from the windows will be clean potable. Water recycled this way will taste cleaner than the best water filter humans have ever devised. The term "grey water" means sewage that has been processed to become suitable to water plants. Remaining contaminants in grey water are suitable fertilizer. So this means a greenhouse can recycle both oxygen and water.

Primary heat loss for a greenhouse will be to the ground. A well insulated greenhouse can be heated directly by sunlight. This may require drawing a curtain of aluminized mylar across the windows and ceiling of the greenhouse at night to prevent radiant heat loss. However, the spectrally selective coating will contain roughly of radiant heat. Whether an aluminized mylar curtain is required will required detailed heat transfer analysis. It might be used as a dynamic heat control system by an automated system.

Windows for both polymer film and glass greenhouses will be double glazed. That means 2 window panes. Between panes the gap will be filled with argon gas, harvested from Mars atmosphere. Argon conducts less heat than normal air. Earth's atmosphere also has 0.9340% argon. The argon will be pressurized more than Mars atmosphere, but less than interior of the greenhouse. Pressure in the gap can be monitored to detect a leak. If gap pressure drops, there's a leak to the outside. If gap pressure rises, there's a leak to the interior.

SpaceNut · 2023-10-30 17:46:42

The standard farming methods of all types are firstly horizontal in nature as it makes use of no structure building which vertical tiering requires.
Sure, for Mars we do need a structure for the enclosure but it serves to keep mars atmosphere and cold from within it but it also allows for men to do this work not machines. As these as well as the ones to make building possible will take time to import and design for mars use.

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#1 2023-10-30 07:52:25

Horizontal Farming on Mars

#2 2023-10-30 17:38:10

Re: Horizontal Farming on Mars

#3 2023-10-30 17:46:42

Re: Horizontal Farming on Mars

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