New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#376 2018-03-23 08:04:45

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,300

Re: Air. Shelter. Water. Food.

GW-
I just saw your note about recent surgery. Recover swiftly and completely! Your presence here is an absolute necessity to keep some of the comments in the ballpark of reality.

Offline

#377 2018-03-23 10:55:30

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,858
Website

Re: Air. Shelter. Water. Food.

Hi Oldfart1939:

I had the surgery,  it was successful,  and I didn't need the implants.  Just a piece of bone removed to decompress the spinal cord.  The symptoms (crippling pain and creeping paralysis) are gone,  so it worked "as advertised".  The first few days back were rather rough,  but I am a lot better now.  I get the staples out next week. 

GW


GW Johnson
McGregor,  Texas

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

Offline

#378 2018-03-23 19:50:27

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

That is a great thing to hear.

Offline

#379 2018-03-24 15:50:20

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

You have pointed out GW Johnson why getting air for a crew will be one of the hardest of things to do from the atmosphere at the lowest of energy costs.

https://mars.nasa.gov/mars2020/mission/instruments/

https://mars.nasa.gov/mars2020/mission/ … nts/moxie/
POWER:300 watts
OXYGEN PRODUCTION RATE:About 10 grams per hour (About 0.022 pounds per hour)
TIME:To produce oxygen from the carbon-dioxide (CO2) gas of the Martian atmosphere:About 2 hours

MOXIE itself will be a reverse fuel cell, developed at the Massachusetts Institute of Technology, converting CO2 into oxygen and carbon monoxide via solid oxide electrolysis. MOXIE is designed so that it will operate for 50 Martian days (about 51 Earth days) and will produce about 20 grams (0.7 ounces) of oxygen per hour. Hoffman and Hecht hope to send a larger version of MOXIE to Mars some time in the 2030s that would produce about 2 kilograms of oxygen per hour.

It is said that an astronaut requires 0.84 kg of oxygen a day.
https://www.quora.com/How-much-oxygen-d … is-exhaled
http://health.howstuffworks.com/human-b … tion98.htm

A person breathes 7 or 8 liters of air per minute. Air is about 20% oxygen. But when you exhale, your breath is about 15% oxygen, so you consumed about 5%. Therefore, a person uses about 550 liters of pure oxygen each day.  Each breath has about 200ml of CO2. With 12 breaths per minute, that yields about 3456 liters per day.

edit: forgot about RobertDyck post on diluent gas also moxie output is pure oxygen

Space Cubes Again? How to Avoid Menu Fatigue with In-Space Cooking

HI-SEAS-pasta.jpg?w=617

http://www.mars-one.com/faq/health-and- … and-oxygen

Offline

#380 2018-03-24 17:17:07

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

Re: Air. Shelter. Water. Food.

I'm sorry, but look at this:

https://mars.nasa.gov/mars2020/mission/ … nts/moxie/

It looks like something a talented teenager might knock up in their bedroom!

Is this really the best that NASA can do with $20 billion a year?  Something that produces 10 grams of oxygen in 2 hours?

I am willing to bet that Musk already has something way more effective designed and ready to go.

As for food I really think that is a box that can be ticked: freeze dried, frozen, dried foods, choc bars, tinned food...there will be a huge variety of food available and the pioneers can probably grow a salad selection, without too much trouble, to supplement those foods brought from Mars.


SpaceNut wrote:

You have pointed out GW Johnson why getting air for a crew will be one of the hardest of things to do from the atmosphere at the lowest of energy costs.

https://mars.nasa.gov/mars2020/mission/instruments/

https://mars.nasa.gov/mars2020/mission/ … nts/moxie/
POWER:300 watts
OXYGEN PRODUCTION RATE:About 10 grams per hour (About 0.022 pounds per hour)
TIME:To produce oxygen from the carbon-dioxide (CO2) gas of the Martian atmosphere:About 2 hours

MOXIE itself will be a reverse fuel cell, developed at the Massachusetts Institute of Technology, converting CO2 into oxygen and carbon monoxide via solid oxide electrolysis. MOXIE is designed so that it will operate for 50 Martian days (about 51 Earth days) and will produce about 20 grams (0.7 ounces) of oxygen per hour. Hoffman and Hecht hope to send a larger version of MOXIE to Mars some time in the 2030s that would produce about 2 kilograms of oxygen per hour.

It is said that an astronaut requires 0.84 kg of oxygen a day.
https://www.quora.com/How-much-oxygen-d … is-exhaled
http://health.howstuffworks.com/human-b … tion98.htm

A person breathes 7 or 8 liters of air per minute. Air is about 20% oxygen. But when you exhale, your breath is about 15% oxygen, so you consumed about 5%. Therefore, a person uses about 550 liters of pure oxygen each day.  Each breath has about 200ml of CO2. With 12 breaths per minute, that yields about 3456 liters per day.

Space Cubes Again? How to Avoid Menu Fatigue with In-Space Cooking

https://i0.wp.com/www.spacesafetymagazi … .jpg?w=617

http://www.mars-one.com/faq/health-and- … and-oxygen


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

Offline

#381 2018-03-24 19:08:14

kbd512
Administrator
Registered: 2015-01-02
Posts: 5,857

Re: Air. Shelter. Water. Food.

Louis,

NASA did not spend all $20B of its budget on MOXIE.  Funding is allocated by priority and need.  If you've never spent your own money to build a prototype of something as simple as an electric generator, let alone try to manufacture an electric generator, you'd quickly discover just how hideously expensive that process can be.  This is about construction of functional devices that do X, Y, or Z.  It's not about how cool it looks or how much money NASA spent on it.  If a teenager is able to build a functional SOXE cell in their bedroom for less money than NASA, then I've yet to see their working prototype.  Incidentally, NASA does spend a portion of its budget on allowing kids to do experiments because they're very creative and not yet as brain-locked into what they think will or won't work as the adults are.

I am willing to bet that if Musk had anything like MOXIE ready to go, then his company would already be NASA's prime contractor because contractors typically try to spend their clients' money rather than their own.  I'm all but certain that he doesn't because his company is a launch services provisioning outfit.  They don't do basic research not immediately applicable to their line of business.  He would simply buy the technology from the same people NASA bought the technology from.  NASA has had people experimenting with this technology long before SpaceX ever existed.  If it really was as easy and simple as you think it is, then someone would've built something by now and sold it to mining companies.  They haven't because it's not that easy.

I have faith in SpaceX's technical competency to handle launch and recovery of rockets.  However, the technical problems you think SpaceX has already solved most likely have not even been considered.  Part of the reason it takes "old space" so long to do something is this crippling zero-defect mentality towards development programs that mandates a nearly impossible level of performance to achieve.  People working with highly experimental technologies have to be permitted to make mistakes, or they can never learn.  As long as nobody makes the same mistake twice, I could care less if we blow up a few rockets on our way to perfection.  SpaceX certainly did.  So what?  NASA saw that they were actively learning from their failures and applying what they learned to their next design, so they didn't get overly upset at the fact that it takes a few tries to get everything right.

These constantly moving design targets are another issue that contractors must chase down.  It's a lot harder to hit a moving target.  SpaceX designed a rocket to their own specifications to do what it does, rather than use arbitrary performance metrics and design characteristics foisted upon them by a political committee that has no first hand experience with designing space launch vehicles.  Nobody told SpaceX, you must use this propellant tank, those rocket engines, and these avionics to do "X".  The mandate to use the absolute pinnacle of rocket technology is what has cost Uncle Sam so much money.  Meanwhile, SpaceX has a rocket that comes within about 10t of the initial lift capability of SLS and, by the way, it costs 1/5th as much per flight, assuming the lowest projections of how much SLS will cost to fly.

You have to look at how these design decisions come about to understand why some appear so facially absurd.  SLS is not the rocket NASA wanted and development hasn't gone any smoother than if the agency was simply allowed to start from scratch and build what they wanted to build.  NASA wanted to do away with the solid rocket boosters and RS-25's entirely.  Congress mandated use of those components to secure funding for SLS.  Consequently, SLS was designed and built with SRB's and RS-25's.  That mandates the most expensive reusable flight hardware known to man, which will now be thrown away after every flight.  I promise you that NASA would never dream up something like that.  STS was our first (and mostly successful) attempt at reusable flight hardware.  It was designed more than four decades ago and the equipment is showing its age.  It's no longer cost competitive with far newer technologies.

Offline

#382 2018-03-24 20:30:26

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

Offline

#383 2018-03-25 05:34:46

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

Re: Air. Shelter. Water. Food.

I realise they didn't have $20 billion, or even $1 billion,  each year to spend on a MOXIE but as you say that is because of their priorities and NASA's priorities have since the early 70s excluded lunar and Mars colonisation and have focussed on robotic exploration of the solar system, creating and provisioning the ISS and a host of scientific experiments.

I think Musk has to be careful not to embarrass NASA too much. Musk knows what is required to make a successful Mars mission and so I just refuse to believe he has not worked on the life support solutions and got some answers ready.

kbd512 wrote:

Louis,

NASA did not spend all $20B of its budget on MOXIE.  Funding is allocated by priority and need.  If you've never spent your own money to build a prototype of something as simple as an electric generator, let alone try to manufacture an electric generator, you'd quickly discover just how hideously expensive that process can be.  This is about construction of functional devices that do X, Y, or Z.  It's not about how cool it looks or how much money NASA spent on it.  If a teenager is able to build a functional SOXE cell in their bedroom for less money than NASA, then I've yet to see their working prototype.  Incidentally, NASA does spend a portion of its budget on allowing kids to do experiments because they're very creative and not yet as brain-locked into what they think will or won't work as the adults are.

I am willing to bet that if Musk had anything like MOXIE ready to go, then his company would already be NASA's prime contractor because contractors typically try to spend their clients' money rather than their own.  I'm all but certain that he doesn't because his company is a launch services provisioning outfit.  They don't do basic research not immediately applicable to their line of business.  He would simply buy the technology from the same people NASA bought the technology from.  NASA has had people experimenting with this technology long before SpaceX ever existed.  If it really was as easy and simple as you think it is, then someone would've built something by now and sold it to mining companies.  They haven't because it's not that easy.

I have faith in SpaceX's technical competency to handle launch and recovery of rockets.  However, the technical problems you think SpaceX has already solved most likely have not even been considered.  Part of the reason it takes "old space" so long to do something is this crippling zero-defect mentality towards development programs that mandates a nearly impossible level of performance to achieve.  People working with highly experimental technologies have to be permitted to make mistakes, or they can never learn.  As long as nobody makes the same mistake twice, I could care less if we blow up a few rockets on our way to perfection.  SpaceX certainly did.  So what?  NASA saw that they were actively learning from their failures and applying what they learned to their next design, so they didn't get overly upset at the fact that it takes a few tries to get everything right.

These constantly moving design targets are another issue that contractors must chase down.  It's a lot harder to hit a moving target.  SpaceX designed a rocket to their own specifications to do what it does, rather than use arbitrary performance metrics and design characteristics foisted upon them by a political committee that has no first hand experience with designing space launch vehicles.  Nobody told SpaceX, you must use this propellant tank, those rocket engines, and these avionics to do "X".  The mandate to use the absolute pinnacle of rocket technology is what has cost Uncle Sam so much money.  Meanwhile, SpaceX has a rocket that comes within about 10t of the initial lift capability of SLS and, by the way, it costs 1/5th as much per flight, assuming the lowest projections of how much SLS will cost to fly.

You have to look at how these design decisions come about to understand why some appear so facially absurd.  SLS is not the rocket NASA wanted and development hasn't gone any smoother than if the agency was simply allowed to start from scratch and build what they wanted to build.  NASA wanted to do away with the solid rocket boosters and RS-25's entirely.  Congress mandated use of those components to secure funding for SLS.  Consequently, SLS was designed and built with SRB's and RS-25's.  That mandates the most expensive reusable flight hardware known to man, which will now be thrown away after every flight.  I promise you that NASA would never dream up something like that.  STS was our first (and mostly successful) attempt at reusable flight hardware.  It was designed more than four decades ago and the equipment is showing its age.  It's no longer cost competitive with far newer technologies.

Last edited by louis (2018-03-25 10:41:54)


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

Offline

#384 2018-03-25 10:23:45

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

I think that Space X has already done so with the embarrassment but its not sticking and is just rolling off the contractors plus Nasa's management backs. Part of that is due to the controls placed on them via the old space military industry as to guard the path to the high ground. All that changed when Nasa began to be a civilian work agency as controlled by the non military in the President, congress and senate. They have forgotten the way and have fostered pork workfare in there districts.

The Nasa of old needs to be restructured to make it productive once more.

Post in response to RobertDycks

GW Johnson wrote:

What RobertDyck says is correct,  whether you do the vacuum pump-as-compressor or the freeze bucket combined with conventional compression.  You're looking at a piece (or pieces) of equipment that mass the best part of a ton,  that consumes the best part of a kilowatt or more,  and produces only grams per minute of output.  There is no way around that.

As far as breathable atmospheres go,  it is already known that pure oxygen will not suffice,  except as an exposure measured only in hours while in a spacesuit.  It'll suck the moisture right out of your lungs.  There's serious medical consequences for that,  as well as a nasty fire hazard. 

Not to mention what really long-term exposures to only enhanced-oxygen concentrations might do to pregnant women and developing children.  We don’t yet know.  Maybe nothing,  maybe something as catastrophic as the thalidomide disaster.  My point is:  that risk is now unknown.  Until it is known and understood,  the only ethical thing to do is avoid it. 

That being said,  I looked at balancing the competing needs of an enhanced-oxygen two-gas mix as a hab atmosphere,  the wish to avoid pre-breathe time decompressing to a low-pressure pure oxygen suit (of any type),  and mitigating the fire hazards of enhanced oxygen content.  I posted that quite recently over at "exrocketman" as "suit and hab atmospheres 2018",  or something like that.

At the end of that article,  I suggested dividing the habitation spaces into two zones with different atmospheres,  both two-gas.  Where the pregnant women and children are,  I suggested real synthetic air (oxy-nitrogen mix at 20.946% oxygen) at 10.1 psia (equivalent to 10,000 feet).  We have millennia of evolutionary experience at those conditions.  We KNOW it works.

For the rest,  I suggested a lower-pressure two-gas mix:  45.45% oxygen with nitrogen,  at 6.2 psia pressure.  Even the pregnant women and developing children can take temporary exposure to this,  as well as the 2.8 psia pure oxygen suits.  The key is for those at risk not to live in this stuff full time while they are vulnerable,  live in the real synthetic air instead.  Everybody else should be able to take the low-pressure enhanced-oxygen mix just fine on a permanent basis.  We have decades of space station and spacecraft experience that confirms this.

Point is,  it's the same two gases we evolved with:  oxygen and nitrogen.  If you cannot effectively make nitrogen on Mars,  then just plan on shipping it in.  It's really that simple. 

Actually,  that's true of all supplies.  “What you cannot make,  you take (with you)”.  That's why the 1950's Mars mission proposals had such large vehicles:  they were planning on taking everything,  100%.  If all else fails,  you can always do that.  You just get to accomplish your mission with fewer flights of smaller vehicles (at lower budget),  if you can make more of your supplies in situ while you are there.

Offline

#385 2018-04-01 18:50:23

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

sort of old DESIGN GUIDELINES FOR CARBON DIOXIDE SCRUBBERS

not moxie but interesting https://motherboard.vice.com/en_us/arti … th-a-laser

This experiment proves that we have the means, here on Earth, to take a waste product of human respiration and turn it back into the input.

I reached out to the authors of this study about whether they thought the finding had any implications for far-future devices where you could create, say, a closed-system respiratory apparatus where people in space could breathe out carbon dioxide and some small vacuum ultraviolet laser could blast it back into into oxygen that could be breathed again.

None of the researchers I emailed responded to me, unfortunately, but, in their analysis, Suits and Parker note that new avenues and alternatives to high energy vacuum ultraviolet lasers are being researched to induce roaming. High energy vacuum ultraviolet lasers do, after all, seem like they would require a lot of power to operate—which could potentially negate any climate benefit, if your mind has gone there—but hey, you never know.

This one uses soda lime absorbs the CO2

AIR-POWERED-SCRUBBER400.JPG?itok=VziESfs6

Strata scrubbers maintain CO2 concentrations below 10,000 ppm (1%).
·       Fans:
    2 x 24 volt fans
    RoHS Compliant
    24 volt input
    5.0 watt power rating

·       Single scrubber suitable for 0-30 persons
·       Multiple scrubbers required for more than 30 persons

Weight: 37lb (17kg) per cartridge
Dimensions: 16” x 12” x 6.5”

Looking at the parts for men to stay on mars the habitat will need a https://en.wikipedia.org/wiki/Carbon_dioxide_scrubber of which I am thinging that a Moxie would do the same thing and that builds a bit of redundancy for a mission to mars.

Not having some numbers for the cabin air for co2 calculations I am not sure if this is better or not. than the moxie unit.

Offline

#386 2018-04-05 10:06:25

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,300

Re: Air. Shelter. Water. Food.

Use of scrubbers as opposed to a moxie unit is in the long run, much less efficient. The moxie unit is returning oxygen to the system instead of making it into a throwaway; reaction:  2 CO2 --------------> O2  + 2 CO; so for every 2 moles of CO2  removed, we get back one mole of Oxygen.                                                            moxie unit

The scrubbers should be available as a backup should the moxie units fail to perform properly or become inoperative.

Last edited by Oldfart1939 (2018-04-05 10:08:32)

Offline

#387 2018-04-06 03:42:52

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

Re: Air. Shelter. Water. Food.

On the subject of food, this farm hab on Antarctica seems to be working well. No reason we shouldn't see something similar as part of Mission One on Mars. This one is going to produce 4-5 kgs of fruit and veg per week, which would certainly help keep a 10 person crew healthy and happy, having a little bit of fresh food to go with the imported meals and ingredients.

https://apnews.com/bb14d1bf3a6143118ba9910b11adb5d8


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

Offline

#388 2018-04-06 19:44:47

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

More links to post Louis has made.
Called the Eden-ISS, the greenhouse exists inside a climate-controlled shipping container.
AAvyIxv.img?h=373&w=624&m=6&q=60&o=f&l=f
The farm can grow food year-round for researchers at the Neumayer III polar station on the Ekstrom Ice Shelf. The researchers plan to grow between 30 and 50 different species, including leafy greens, peppers, strawberries, radishes, and tomatoes, as well as herbs like basil and parsley.

Offline

#389 2018-04-08 09:53:27

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,300

Re: Air. Shelter. Water. Food.

Once again, we have another energy-intensive unit in the above. Do they plan to have bees inside for pollination of the peppers, tomatoes, and strawberries? In a bee-free environment, they will of necessity be limited to leafy vegetables and root crops (Swiss chard, lettuce, cabbage, endive, radishes, beets, carrots, and turnips, etc.).

Offline

#390 2018-04-08 11:35:28

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

In the crops topic I think there was discusion of bee less polination techiques as it can be done to a degree...

Offline

#391 2018-04-08 12:03:14

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,288
Website

Re: Air. Shelter. Water. Food.

Crops

Other insects can pollinate: bumblebees, pollen wasps, bee flies, hover flies, mosquitoes, ants, butterflies, moths, flower beetles, bats, humming birds, sunbirds, "honeyeater" birds, and even some lizards and small mammals. However, only honey bees produce honey.

Autonomous Flying Microrobots (RoboBees)
Robobee-e1473081706400.jpeg?w=800&h=780&auto=format&q=90&fit=crop&crop=faces%2Centropy

Offline

#393 2018-06-16 09:13:34

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

Survival rate of dust storm via solar power being posted on pages 8 & 9 of topic Going Solar...the best solution for Mars

Offline

#394 2018-06-25 17:49:58

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

With regards to afresh BFR cargo manifest we are now faced with the question on food as to how much is with and without water and how much water do you need plus power to be able to eat the food once we do make it.

How NASA Is Solving the Space Food Problem; As scientists engineer a menu for potential Mars exploration, several challenges emerge

That much food for six astronauts could weigh about 12 tons, according to a 2012 estimate — and that's not counting its packaging. Rather than trying to haul all that on a spaceship, NASA wants to load a vessel with food and send it to Mars before the astronauts set off. That means food scientists have to make meals that will stay good for five years.

This is the small mission by Mars one
http://www.mars-one.com/faq/health-and- … and-oxygen

The fresh view is to make it a greenhouse option to control the ability
To survive on Mars, we need a 'technology that replaces what the Earth does.' This tube might be NASA's best hope.

The Mars Lunar Greenhouse is designed to supply 100% of the air and 50% of the food an astronaut needs for 2 years.
5af1cf926598e02b008b45a2-960-631.jpg

https://cals.arizona.edu/lunargreenhouse/

Of course we could grow the food but what we take needs to be a manifest of what we food is not grown. Missions for Mars: What's for Dinner?

Astronauts on space shuttle missions and flights to the International Space Station currently get 3.8 pounds (1.7 kilograms) of food per day. At that rate, astronauts would need almost 7,000 pounds (3,000 kg) of food per person for a five-year round trip to Mars

So is the first greenhouse for sustainability or is it to fill a need for what we did not take?

NASA scientists have identified 10 candidate crops that seem to fit the bill for astronaut food: lettuce, spinach, carrots, tomatoes, green onions, radishes, bell peppers, strawberries, fresh herbs and cabbages.

Offline

#395 2018-11-20 18:16:56

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

We have been talking about the economy of mars and the corner stone of man being able to stay and it seems that CO2 is as high on the pole as the others for this topic as a requirement to be able to stay.

Direct Generation of Oxygen via Electrocatalytic Reduction of Carbon Dioxide in an Ionic Liquid

Offline

#396 2018-11-21 03:43:55

elderflower
Member
Registered: 2016-06-19
Posts: 1,262

Re: Air. Shelter. Water. Food.

You cannot rely on unproven systems, such as greenhouse cultivation on Mars (the moon can always be resupplied in a few days). There must be, in place, iron rations for everybody to survive for two conjunction periods for the early expeditions. When you develop confidence in a diverse range of crops and separately supported facilities (structurally and functionally) and in your ability to resupply on schedule you can possibly reduce this requirement.

Offline

#397 2018-11-21 07:36:03

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,288
Website

Re: Air. Shelter. Water. Food.

elderflower wrote:

You cannot rely on unproven systems, such as greenhouse cultivation on Mars (the moon can always be resupplied in a few days). There must be, in place, iron rations for everybody to survive for two conjunction periods for the early expeditions. When you develop confidence in a diverse range of crops and separately supported facilities (structurally and functionally) and in your ability to resupply on schedule you can possibly reduce this requirement.

Ok. I would argue that first missions must bring enough food for the entire mission, the greenhouse on the first mission will be an experiment. Fresh food will be a bonus. Mars greenhouse must be proven before permanent settlement. Once permanent settlement occurs, produce enough for stored food from locally produced produce for at least one conjunction period (26 months), plus "iron rations" for one conjunction period. When settlers first arrive, supplies should include enough regular stored food for one conjunction period plus "iron rations" for another. Perhaps picky detail that isn't much different from what you said.

The other thing is "iron rations" should be palatable. Use something like freeze dried food from Mountain House. That's a commercial brand that produces freeze dried food for hiking, etc. NASA claims food they produce for ISS won't last 26 months (shelf life), but Mountain House guarantees their food will last at least 30 years. That's taste guarantee, it will remain nutritious even longer. The other thing is modern freeze dried food is compact and light-weight, but it's things like beef stew, spaghetti, beef stroganoff with noodles, chicken and mashed potatoes, chicken teriyaki, chili mac with beef, turkey dinner casserole, Italian style pepper steak with rice and tomatoes, lasagna with meat sauce, mac & cheese, Mexican style rice and chicken, pasta primavera, sweet & sour pork. The term "iron rations" comes from the British army in World War 1. It was "preserved meat, cheese, biscuit, tea, sugar and salt" carried by all British soldiers in case they were cut off from regular food supplies. Rations used by voyageurs of the Canadian fur trade in the 1700s and 1800s ate pemmican. That's a mixture of rendered fat, crumbled meat jerky (bison, elk, deer, or moose), and dried berries such as cranberries, saskatoon berries (aka juneberry), or chokeberries. Pemmican for special occasions had dried blueberries, cherries, choke cherries, or currants. Today we can do a lot better than pemmican.

Offline

#398 2018-11-21 09:17:46

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

I agree first mission or 2 even will be greenhouse demonstration, piece of mind with a bonus of green foods. Much like the ISS man will have their health monitored and there will be many a supplement in vitamins and minerals to keep them that way.
There will be lots of demonstrators and or survivability setups that we will setup in these first few missions as indicated by the topic title and they will include others.

Offline

#399 2019-03-17 11:27:04

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

I am not sure but did we ever come to a final number for energy required per person for mars start to sustainablity conditions for mars  crewmen as we increase mans presence? That number comes into play for mobility and human powered device use, exercise recapturing of that energy and how we stay alive with ts use.

Offline

#400 2019-03-18 21:06:10

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 25,979

Re: Air. Shelter. Water. Food.

The air we breathe is a mixture of gases including nitrogen, oxygen, water, argon, carbon dioxide and trace gases. The air that is inhaled is about 20-percent oxygen, and the air that is exhaled is about 15-percent oxygen, so about 5-percent of the volume of air is consumed in each breath and converted to carbon dioxide. Therefore, a human being uses about  550 liters of pure oxygen (19 cubic feet) per day. People inhale and exhale approximately 7 or 8 liters of air each minute or 11,000 liters per day or 15.27 kg.
https://www.aqua-calc.com/calculate/vol … nce/Oxygen

http://www.cres.gr/kape/publications/pa … OLYSIS.pdf

One liter of water will thus produce 111/0.0899 =1235 liters of hydrogen and 888.81/1.429 = 622 liters of oxygen. Or about 18 liters of water to electrolysis to meet the days need. A litre of water has a mass almost exactly equal to one kilogram. 1 kg of water (55.55 moles).
The electrolysis of water requires a minimum of 237.13 kJ of electrical energy input to dissociate each mole. Energy for electrolysis: 237.13 kJ * 55.55 = 13.173 MJ
https://www.rapidtables.com/convert/ele … -watt.html
237.1 kJ of electricity must be supplied in 1 minute (60s). 237.1 kJ/60 s = 3.95 kW

Offline

Board footer

Powered by FluxBB