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#151 2017-01-02 22:21:02

SpaceNut
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From: New Hampshire
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Re: Greenhouse - hydroponics vs soil

Lake Matthew Team - Cole wrote:

ZLD

Oldfart1939 wrote:

I'm not saying that it's not a good system. Just the amount of mass required seems to be excessive for the early efforts at colonization. Your system would be 2nd Generation technology.

?  This little ZLD unit processes 24,000 liters per day.  Fits on a flatbed. 

You might consider the tech and its uses, before diving into those greenhouse process flows.  Could save some time and trouble.

5323c6e4-ce61-404b-b3c0-08f23ed31ec9-large.jpeg

Looking at the diagram on page 3 we could apply low tech to doing most of this as the power noted on page 2 is 1,835 kilowatts which will not be possible on a first mission....

1. Use solar thermal panels and concentrating reflective panels to raise the temperature for the heat exchanger. The pumps can be solar PV cell powered with battery storage as needed.
2. The dearator is a tank with water in it to act as a bubbler, the gasses to vent out of as new water is put into the unit.
3. condensed water is then feed into another heating chamber which operates more like a moonshiners still  with how it uses evaporation and cooling of what evaporates as it gets collected. We could use a martian air cooler exchanger for this step. The solids are then passed out of solution as cleaning would do for the chamber.

We can also prefilter the waste water process via a large tube filled with clean sand using gravity to help the process changing the sand as needed.

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#152 2017-01-02 22:29:52

SpaceNut
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Re: Greenhouse - hydroponics vs soil

Sorry about having to move the post:

Lake Matthew Team - Cole wrote:
SpaceNut wrote:

...the power noted on page 2 is 1,835 kilowatts which will not be possible on a first mission...

That's cleaning 404 gallons per minute.

What flow rate are you imagining for the first mission?  Maybe scale your ZLD power need accordingly.

https://www.latitude38.com/lectronic/im … reboat.jpg

That is a lot of water which will not be needed from what I can see on first missions as we do not have that much water going with a crew to even drink let alone shower with.....

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#153 2017-01-02 22:36:01

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

Just looking at the process system through the jaundiced eye of an industrial process chemist, that unit probably weighs in at something around 3 to 5 tons? The size and mass of such a unit is far beyond the early settlement's importation capacity to afford. Any guesses how much it would cost to transport to Mars? The volume is significant as well, since much of it is empty tankage. Just what the early colonists need to import! Not! Whatever system can be fit into the volume of 2 large refrigerators and weighs less than 350 kg is about the limit for an early colony water processing system.

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#154 2017-01-02 22:46:27

SpaceNut
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Re: Greenhouse - hydroponics vs soil

Current life support unit that takes in sweat, humidity, urine ect...onboard the ISS
nasa_water_treatment_system.jpg

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#155 2017-01-02 23:05:59

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

Oldfart1939 wrote:

...that unit probably weighs in at something around 3 to 5 tons? The size and mass of such a unit is far beyond the early settlement's importation capacity to afford...

You realize a 4 ton cargo is less than 1% of an ITS payload, right? 

For a mission-critical life-support system, np.  Do at least get familiar with the tech.

Last edited by Lake Matthew Team - Cole (2017-01-02 23:08:13)

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#156 2017-01-02 23:53:23

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

We are NOT close to considering a ITS at this juncture. Anyone who believes the first manned missions will be using such a space vehicle for them is living in LaLa land. I've been thinking of a vehicle with roughly the performance of an uprated Falcon Heavy--using the new Raptor Methylox engines in place of RP-1 & LOX, to carry a 6 or 7 person crew, and a second vehicle carrying maybe 8 metric tonnes to Mars' surface. That payload must include a rover, a Nuclear powerplant, food, an Oxygen concentration system, a Methane Sabatier reaction system, construction materials, in addition to a water and air processing system. Between both spacecraft, in addition to a prepositioned Habitat module, we may have a payload in addition to bodies and their immediate needs for life support of maybe 12 tonnes. I am VERY familiar with the tech!

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#157 2017-01-03 07:56:30

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

Nano-Greenhouse

Oldfart1939 wrote:

We are NOT close to considering a ITS at this juncture. Anyone who believes the first manned missions will be using such a space vehicle for them is living in LaLa land. I've been thinking of a vehicle with roughly the performance of an uprated Falcon Heavy--using the new Raptor Methylox engines in place of RP-1 & LOX, to carry a 6 or 7 person crew, and a second vehicle carrying maybe 8 metric tonnes to Mars' surface. That payload must include a rover, a Nuclear powerplant, food, an Oxygen concentration system, a Methane Sabatier reaction system, construction materials, in addition to a water and air processing system. Between both spacecraft, in addition to a prepositioned Habitat module, we may have a payload in addition to bodies and their immediate needs for life support of maybe 12 tonnes. I am VERY familiar with the tech!

A 6-man crew, packed onto a FH and carrying such a tiny equipment payload, would be only a scouting mission, or precursor to settlement.  There's no compelling reason, and precious little payload, for greenhouse gardening in that scheme.  Neither is there need to cripple greenhouse designs under those crushing mission-design constraints, which are your own.  Or if you want it, maybe you should develop a nano-greenhouse design in another thread, so that this thread can explore production greenhouses.

Last edited by Lake Matthew Team - Cole (2017-01-03 12:36:29)

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#158 2017-01-03 09:25:28

RobertDyck
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Re: Greenhouse - hydroponics vs soil

Lake Matthew Team - Cole wrote:

A 6-man crew, packed onto a FH and carrying such a tiny equipment payload, would be only a scouting mission, or precursor to settlement.  There's no compelling reason, and precious little payload, for greenhouse gardening in that scheme.

Image of Mars Direct. Remember the Mars Society was founded by Dr. Robert Zubrin, he and his partner David Baker wrote Mars Direct in the last quarter of 1989 and first half of 1990. This is a painting by an artist depicting their vision. Taken from the Mars Society website as it was in 2001.
surface1.jpg
This is not small. Mars Direct was intended to launch on the Ares launch vehicle, proposed as part of Mars Direct. SLS block 2 effectively is the implementation/realization of Ares. The Ares V from Constellation had modifications, SLS block 2 is closer to the original Ares. But what we're saying now is a modified Falcon Heavy with Raptor engines and LCH4/LOX could launch something like this.

I've also argued that the first floor of the habitat will have landing rocket engines, propellant tanks, RCS thrusters, propellant tanks for RCS thrusters, mechanism of the landing legs, life support, airlock, stairs to the upper floor, and storage compartment for the rover. That storage compartment is shown here are an open garage. Surface science equipment and the inflatable greenhouse would also be stored there during transit. Solar panels would somehow be folded into the lower floor during launch then deployed in space. They would be folded for Mars atmospheric entry. Then on the surface of Mars they would be removed by astronauts and set up on the ground with power cables back to the hab. This image shows the solar panels behind and to the left of the hab. But all that means the lower floor will be mostly solid equipment. The lower floor won't be usable at all during transit, but on Mars the storage compartment will be empty so could be used as a workshop or lab. But that will only be about the size of a single car garage, not the whole floor. So don't expect a lower floor as large as MDRS or FMARS. A real Mars Direct hab may look more like this image from the year 2000 movie "Mission to Mars".
2011-review-mars.jpg

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#159 2017-01-03 09:58:22

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

Villa Real

RobertDyci wrote:

This is a painting by an artist depicting their vision.

I always liked that terracotta roof.  It's homey, a nice Italian touch. 

Or is it "are-cotta" on Mars?

Unfortunately the depicted greenhouses are far too small to be useful and/or far too exposed to survive.  Cosmic rays and -100 C nights = veggie toast.  Nano-greenhouse payloads just can't get the job done.

Can we talk about greenhouses that do get the job done, here?

Answer:  Yes, we can talk about them.  At the moment I'm especially interested in optimized fertilizer production and delivery, including useful hydroponic tweaks.

Last edited by Lake Matthew Team - Cole (2017-01-03 10:00:56)

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#160 2017-01-03 10:02:44

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

Lake Matthew Team-Cole

There's nothing wrong with "thinking big," but you are looking ahead to what might be called a 3rd generation system. Thinking generously for food preparation, sanitation, and personal care might add up to a 5 gallons per day of purified potable water per person. The other "gray water" would be minimally processed for agricultural use. Let's recite the problems in order: (1) find some Martian ice or subsurface water; (2) test said water for mineral and toxic substance content; (3 use the small purification system onboard the habitat module or a larger system brought in on a payload vessel to begin accumulation of a reliable water supply. This system could be built by incorporation of several different concepts: ion exchange resins, reverse osmosis, activated carbon "polishing" to improve taste, and or distillation. A good Chemical Engineer could design and build a system that would meet my specifications and produce say--150 gallons per day...or Sol. It certainly would be transportable in one of the earliest payloads, as it would meet my earlier stated volume and mass limits. If water is rationed, as it will be for the first few years, a system such as the one I've described should be able to handle the water requirements of up to 50 crewmembers. Some improvements in toilets will reduce the gallons per flush down to something similar to that used on airliners, and this subsequently allows a bit more water for personal hygiene.

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#161 2017-01-03 10:24:23

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

Oldfart1939 wrote:

...build a system that would meet my specifications...

Your specifications are incompatible with a production greenhouse.  We need to focus on what's required for a production greenhouse.

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#162 2017-01-03 10:56:46

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

IoT Hydroponics

Btw, IoT hydroponics is actually a thing now.  Examples:  Fujitsu, BLT Robotics, FlowThings.io, Gro.io.

Gro.io wins the prize for cuddly graphic design, but Fujitsu is doing the more interesting work.  Notice how they've used their IoT system to grow produce with "unusually low levels of potassium, a feat only pulled off at one other facility."  That sounds like the sort of precision growth that would be very hard to accomplish without IoT hydroponic control.

feature_groio.jpg

Update:  "Greenhouse Horticulture SaaS"

I see Fujitsu has commercialized their IoT hydroponics as "Greenhouse Horticulture SaaS".  Nice presentation of the data and hardware.

Also, for those of you who find Perfect Day dairy fabs insufficiently bovine, the Fujitsu doc presents their other IoT innovation, "GYUHO SaaS (Connected Cow)".

Last edited by Lake Matthew Team - Cole (2017-01-03 12:38:49)

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#163 2017-01-03 13:42:23

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Re: Greenhouse - hydroponics vs soil

Mass Matters?

SpaceNut wrote:

What we still need to nail down is the mass for the soil trays plus what depth sizes as that's crop dependant, support structure for trays not at ground level, quantity of hydroponic tubing for solution delivery plus other parts...

I understand hydroponic substrates are commonly about 0.5 m deep.  Crops with shallow roots might get 0.3 m.  If the substrate is just sand, the mass is ISRU, and largely irrelevant.

Hydroponic tubing and widget mass adds up, but here again mass is only truly limiting if you're hauling it from Earth.  Many plastics can be used for piping etc., so why not manufacture the hardware via ISRU plastic + injection molding?  For example, if the methane plant produces excess methane, you might use that excess as feedstock for an AirCarbon PHA plastics plant.  Alternately, you might make PE plastic more efficiently from a GM cyanobacterial plant

Other options?  An ISRU plastics industry would have many uses beyond hydroponics, and if fully developed it could knock very significant mass off the cargo flights.  What are promising methods?

n0i0l0-b781259566z.120140204170508000gcc1i8toh.2.jpg

Last edited by Lake Matthew Team - Cole (2017-01-03 13:44:01)

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#164 2017-01-03 13:46:41

RobertDyck
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Re: Greenhouse - hydroponics vs soil

To be clear to the new guy, the painting of Mars Direct depicts sand bags filled with Mars regolith. It's radiation shielding. A permanent settlement requires 2.4 metre thick regolith for complete radiation shielding, but a science/scouting mission will use sand bags.

I talked directly with Dr. Penelope Boston about polymer film for an inflated greenhouse. She wrote a paper in the "Case For Mars" papers before the founding of the Mars Society. I found PCTFE, sold by Honeywell under the brand name Clarus. It becomes embrittled at -240°C. The coldest location recorded by Mars Global Surveyor at the south pole during southern winter was -140°C, so this material handles 100° colder than the coldest spot on Mars.

We also talked about radiation. According to papers published by the team for the MARIE instrument on Mars Odyssey, Mars atmosphere blocks 90% of heavy ion galactic cosmic rays. That's 90% at a high altitude location such as Meridiani Planum where Opportunity landed. It blocks 98% to 99% at low altitude locations such as the bottom of the dried up ocean basin in the northern hemisphere. What gets through is proton radiation which comes from the Sun. Atmosphere blocks some light ion GCR, but the lighter the radiation particle the less atmosphere blocks it.

Plants can withstand radiation much better than humans. The surface of Mars receives 50% as much radiation as ISS. And I already gave the difference regarding types of radiation. So plants don't need radiation shielding on Mars. The best Mars greenhouse uses ambient light.

As for temperature, Mars atmosphere is so thin that atmospheric heat loss is minimal. And the same spectrally selective coating that NASA currently uses for space station and spacecraft windows will be applied. That blocks UV, and controls IR. It can reflect more long wave IR from warm things like the floor, and less short wave IR from extremely hot things such as the surface of the Sun. That traps heat in. The majority of heat loss will come from the ground. Besides, we also want to use 2 pane windows, or 2 layers of polymer film, with argon filling the gap. That helps prevent heat loss.

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#165 2017-01-03 15:33:52

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

What we have here is a group discussion that didn't set up any guidelines w/r scale of the enterprise. Since no human has yet set foot on Mars, I was thinking of an agricultural "starting point," and not a full scale production facility. Until we get there and have an experimental unit to see "what works,' as opposed to that which does not...arguments such as the one which has seemingly developed here are moot.

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#166 2017-01-03 16:07:15

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

RobertDyck wrote:

To be clear to the new guy, the painting of Mars Direct depicts sand bags filled with Mars regolith. It's radiation shielding. A permanent settlement requires 2.4 metre thick regolith for complete radiation shielding, but a science/scouting mission will use sand bags.

I talked directly with Dr. Penelope Boston about polymer film for an inflated greenhouse. She wrote a paper in the "Case For Mars" papers before the founding of the Mars Society. I found PCTFE, sold by Honeywell under the brand name Clarus. It becomes embrittled at -240°C. The coldest location recorded by Mars Global Surveyor at the south pole during southern winter was -140°C, so this material handles 100° colder than the coldest spot on Mars.

We also talked about radiation. According to papers published by the team for the MARIE instrument on Mars Odyssey, Mars atmosphere blocks 90% of heavy ion galactic cosmic rays. That's 90% at a high altitude location such as Meridiani Planum where Opportunity landed. It blocks 98% to 99% at low altitude locations such as the bottom of the dried up ocean basin in the northern hemisphere. What gets through is proton radiation which comes from the Sun. Atmosphere blocks some light ion GCR, but the lighter the radiation particle the less atmosphere blocks it.

Plants can withstand radiation much better than humans. The surface of Mars receives 50% as much radiation as ISS. And I already gave the difference regarding types of radiation. So plants don't need radiation shielding on Mars. The best Mars greenhouse uses ambient light.

As for temperature, Mars atmosphere is so thin that atmospheric heat loss is minimal. And the same spectrally selective coating that NASA currently uses for space station and spacecraft windows will be applied. That blocks UV, and controls IR. It can reflect more long wave IR from warm things like the floor, and less short wave IR from extremely hot things such as the surface of the Sun. That traps heat in. The majority of heat loss will come from the ground. Besides, we also want to use 2 pane windows, or 2 layers of polymer film, with argon filling the gap. That helps prevent heat loss.

Temperature:

-100 C kills a production surface greenhouse because the net radiative, convective and conductive heat loss quickly climbs toward MW range, far too great to counter with batteries, double panes, IR filters, solar heat stores and the like.  Example greenhouse dome heat loss calcs.

Cosmic rays:

Lethal ionizing damage in LEO is documented from the late 80's.  Dose rate in the LEO spacecraft is of the same order-of-magnitude as on Mars:  ~100-500 micro Gy/d inside LEO spacecraft, vs. ~190-210 micro Gy/d on the exposed martian surface.  Therefore the LEO results should be informative wrt an exposed martian greenhouse.

Cosmic rays can harm plants by several means.  That's why current greenhouse designs employ at least 2 m of shielding to protect against those cosmic rays.   RobertDyck, do you think the architects are "hiding under the bed", irrationally?

Studies on space effects on plants
A comparison of various studies has clarified how space effects are deeply influenced
by plant characteristics (e.g. species, cultivar, stage of development, tissue architecture
and genome organization) (Holst and Nagel 1997). In relatively short-term space-flight
experiments, it has been pointed out the space environment causes chromosome aberration
and changes in the cell cycle of plant cells. This may be due to either microgravity or
increased cosmic rays in space or resulting from unfavorable growing conditions in the
plant growing unit. Structural and functional changes in the DNA molecule are responsible
for most of the damage expressed after exposure to ionizing radiations, at both the
cellular and the systemic levels. DNA modifications range from single base alterations,
base substitutions, base deletions, chromosomal aberrations to epigenetic modifications.
In general, radiation exposure can induce both negative and positive effects on plants,
and the mutations at the base of these effects can also be transmitted to the progeny
(Mei et al. 1998; Yu et al. 2007). Apart from reduced germination, among the detrimental
effects, there is often reference to embryo lethality, dwarf architecture, modification
of floral morphology with altered occurrence of fertile floral elements (Kranz 1986;
Sah et al. 1996). On the other hand, stress conditions, like the exposure to ionizing
radiations, can have stimulatory effects on specific morphological parameters and can
increase the yield of the plants in terms of growth, reproductive success and ability to
withstand water shortage (Maity et al. 2005; Yu et al. 2007; Melki and Dahmani 2009).
A few space-flight experiments have attempted to test the effects of the space environment
on plant reproduction. For instance, Arabidopsis thaliana and wheat plants were
grown in space for different durations (Mashinsky et al., 1994; Salisbury et al., 1995). 
They were found to produce and develop flowers, but the flowers produced more sterile
seeds than did ground control plants. These experiments could not specify the cause for
such failure in seed production.

Last edited by Lake Matthew Team - Cole (2017-01-03 16:13:20)

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#167 2017-01-03 18:13:04

SpaceNut
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Re: Greenhouse - hydroponics vs soil

Response to post #163

Sand depth of .5m - .3m does not sound like all that much until you have to move it by hand and begin to look at how much mass that is to support not on the ground unless its on top of some sort of aerogel insulation...

Here are a couple useful links for materials mass for a cubic meter tables:
http://www.simetric.co.uk/si_materials.htm
http://www.aqua-calc.com/page/density-t … ank-Silica

Based on the table the range of sand could fall within 1200 kg/cu.m. to a high of 2020 kg/cu.m. depending on size of grain and what type of mineral sand it is and how wet it is which on mars seems to be based on the rovers x mass will look it up as its in one of the topics....

I have moved via wheel barrow and shovel 10 Tons of sand and 10 tons of pea size stone So I know how much work that is.....over the course of a week or so by myself at age 45 which is quite some time ago....So we definitely need machines to aid with the moving of sand from remote locations to the local greenhouse area..

I have posted before about small motorized battery powered small tools such as a wheel barrow for space suit use which would be where we are starting the incremental steps to a full fledge greenhouse someday after multiple landings.

We do have several plastics pages and links to the mars homestead web documents which I hope you can find if not when I get to it I will update this post with them. To make plastics thou is with heavy equipment that we do not have the potential to send to mass yet unless there are some equipment that does scale down....

Definitely these things are all possible once we have a good lock on surviving on the surface and coming back healthy.

I see that in post #161 that you would like a 100 colonist "full function" production greenhouse and I will would to put the posts that you have made into that new topic just as soon as I can.

We must remember that we all do not have the same starting point for knowledge and that while you may feel the current topic is nano scale we are looking at it from, what can we do with nothing instead with a step by step approach to how to build on Mars when we are mass constrained for mars landings. With current levels and future timeline projects until we have that magical, ah hah moment and we can land 100 plus tons of payload plus ship on the mars surface.

post # 158 images show what we thought we would be already to land todays timeline and past of which we are no where even close to it....

We do need to use our expertise wisely and with thought that just maybe some of thse on this forum are just your average joe and not life size engineers with super powers....

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#168 2017-01-03 19:39:42

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

The Best

SpaceNut wrote:

We must remember that we all do not have the same starting point for knowledge and that while you may feel the current topic is nano scale we are looking at it from, what can we do with nothing instead with a step by step approach to how to build on Mars when we are mass constrained for mars landings. With current levels and future timeline projects until we have that magical, ah hah moment and we can land 100 plus tons of payload plus ship on the mars surface.

post # 158 images show what we thought we would be already to land todays timeline and past of which we are no where even close to it...

My guess is that SpaceX intends to cut a deal with the incoming Administration.  SpaceX gives the federal government a very good price on a package of ITS launches - a yuge package, very smart, the best, with luxurious quality and other Trumpisms. 

As part of the deal SpaceX commits to employing many workers presently employed at existing NASA contractor sites (e.g. Michoud Assembly Facility).  In exchange the federal government ends SLS development (e.g. at Michoud) and redirects much of that money to SpaceX and its new employees, to get ITS done.  Test flights begin in the early 2020s and all ambitions for crewed Mars missions fly with the ITS. 

SpaceX never launches a crewed FH to Mars.

My guess.

Last edited by Lake Matthew Team - Cole (2017-01-03 19:43:48)

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#169 2017-01-03 20:07:30

RobertDyck
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Re: Greenhouse - hydroponics vs soil

More new guy stuff. Posted on other threads in 2014...

RobertDyck wrote:

I have a set of papers published by the team for the MARIE instrument on Mars Odyessey. I saved a copy on the local chapter website.
Radiation Climate Map
Mars Flux Paper
FC-Nara-Paper
PS-Nara-Paper

The first two papers have the same charts at the end. The charts give numbers. With total radiation in the range of 20 - 24 REM/year for any place we would want to go, results of 0.5 REM/year neutron is relatively small. US nuclear reactor workers are allowed 5 REM/year, and radiation from a reactor will be almost exclusively neutron.

There is a paper from Curiosity, but I don't have a current subscription to the journal Science.
Mars’ Surface Radiation Environment Measured with the Mars Science Laboratory’s Curiosity Rover

mariemax.jpg mariemin.jpg

Legend: Particle Type = proton, alpha, light, medium, heavy

Radiation - how dangerous is it really?

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#170 2017-01-03 20:48:15

Lake Matthew Team - Cole
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Re: Greenhouse - hydroponics vs soil

None of which counters our focused observations on greenhouse hazards.

RobertDyck wrote:

US nuclear reactor workers are allowed 5 REM/year, and radiation from a reactor will be almost exclusively neutron.

And primary cosmic rays are mostly protons, not neutrons.  Which is why NASA doesn't rely on reactor studies for estimation of crew exposure limits.  Consider a more relevant paper, such as Crew Radiation Exposure Estimates from GCR and SPE Environments During a Hypothetical Mars Mission.

RobertDyck wrote:

There is a paper from Curiosity, but I don't have a current subscription to the journal Science.
Mars’ Surface Radiation Environment Measured with the Mars Science Laboratory’s Curiosity Rover

You don't have a subscription, but you have us, your friendly forum colleagues.  That's the paper I just gave you.

Last edited by Lake Matthew Team - Cole (2017-01-03 21:27:05)

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#171 2017-01-03 20:49:45

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

SpaceNut wrote:

Sand depth of .5m - .3m does not sound like all that much until you have to move it by hand and begin to look at how much mass that is to support not on the ground unless its on top of some sort of aerogel insulation...

Here are a couple useful links for materials mass for a cubic meter tables:
http://www.simetric.co.uk/si_materials.htm
http://www.aqua-calc.com/page/density-t … ank-Silica

Based on the table the range of sand could fall within 1200 kg/cu.m. to a high of 2020 kg/cu.m. depending on size of grain and what type of mineral sand it is and how wet it is which on mars seems to be based on the rovers x mass will look it up as its in one of the topics....

I have moved via wheel barrow and shovel 10 Tons of sand and 10 tons of pea size stone So I know how much work that is.....over the course of a week or so by myself at age 45 which is quite some time ago....So we definitely need machines to aid with the moving of sand from remote locations to the local greenhouse area..

I have posted before about small motorized battery powered small tools such as a wheel barrow for space suit use which would be where we are starting the incremental steps to a full fledge greenhouse someday after multiple landings.

On of the best small pieces of equipment we could consider for transport to Mars to lighten the workload is a small tractor-frontloader known as a Bobcat. Fitted out with a suite of accessories, it would sure make the work easier than digging and moving regolith by hand in wheelbarrows, but has the capability of doing some decent excavation and covering hab modules with soil. Yeah, this is "off topic" of greenhouse--soil versus hydroponic, but important, nevertheless. They are available with a nice excavating front loader, an auger for drilling holes, and also a forklift.

Last edited by Oldfart1939 (2017-01-03 20:51:59)

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#172 2017-01-03 20:59:48

Oldfart1939
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Re: Greenhouse - hydroponics vs soil

Reinventing the wheel?

Almost all the concern over radiation hazards is succinctly discussed in Dr. Zubrin's book, "Entering Space."

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#173 2017-01-03 21:07:48

RobertDyck
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Re: Greenhouse - hydroponics vs soil

Oldfart1939 wrote:

a small tractor-frontloader known as a Bobcat.

I was a member of the Mars Homestead Project phase 1: the Hillside Settlement. A Bobcat or something similar was basic equipment. "No Duh!"

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#174 2017-01-03 21:10:23

RobertDyck
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Re: Greenhouse - hydroponics vs soil

Oldfart1939 wrote:

Reinventing the wheel?

Almost all the concern over radiation hazards is succinctly discussed in Dr. Zubrin's book, "Entering Space."

What he said!

Could I suggest a list of basic books for someone new to Mars?
Amazon books - sponsor the Mars Society

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#175 2017-01-03 21:17:12

Lake Matthew Team - Cole
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Registered: 2016-12-21
Posts: 119
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Re: Greenhouse - hydroponics vs soil

Tools

Oldfart1939 wrote:

One of the best small pieces of equipment we could consider for transport to Mars to lighten the workload is a small tractor-frontloader known as a Bobcat. Fitted out with a suite of accessories, it would sure make the work easier than digging and moving regolith by hand...

True, but a tractor-drive has limited mobility on rough ground.  You'd want a more versatile loader, like the Caterpillar P-5000, for greenhouse construction.  Feature demo at the link.

What?

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