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Native Water sources = abundant Oxygen & Hydrogen: but where will NITROGEN and CARBON come from?

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WKTaylor

Well-known member
Sep 24, 2001
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Native Water [Moon, Mars, etc] = abundant Oxygen & Hydrogen... but where will adequate NITROGEN and CARBON come from?!?

I get the fact that H2O ‘water’ in any form [vapor, ice, liquid] can be easily disassociated to become Hydrogen and Oxygen... for BASICS of life [breathing oxygen and water]... and for liquid fuel propellants [O2+H2]. Electrical power from solar or nuclear or 'fuel cell' technologies is readily available. HOWEVER, as I see it all-around-me, LIFE sustainment and many other essential functions, also crave/need its share of NITROGEN and CARBON for a host of secondary, very important, functions... inert and active chemistry.

Early spacecraft operated at reduced cabin pressure = partial pressure of pure oxygen of ~4-to-5-PSI... to minimize need for liquid gas consumables, be ‘non-toxic’, to reduce the fire/explosion potential and obviously reduce vehicle mass due to reduced structural weigh operating at low pressurization loads. However, modern spacecraft that have long-duration crews... add ~50% nitrogen to attain a higher total pressure atmosphere that is far more comfortable/sustainable for crews.

For instance, the reason Apollo 13 spacecraft became so abusively ‘cold’ to the astronauts [after heaters were shut-off to conserve energy] was the inability to maintain body heat with so low an atmospheric pressure [oxygen molecules, ~4.5-PSI] and the relatively light weight/porous clothing provided.

Likewise plants and animals have an intrinsic need for nitrogen and carbon for chemical growth [along with a host of other lesser chemicals common to earth soils]. As I understand farming, nitrogen and carbon are essential to promote plant growth... hence provide ‘food’ for animal life. Space station atmosphere provides 'stealth' nitrogen to its 'new' hydroponic plants for growth.

SO... Where is the necessary abundance of Nitrogen and Carbon to support ‘human life’ to be found ‘FAR AWAY from Earth... like the moon and Mars? I Have NEVER heard this discussion in space exploration circles... what am I missing?



Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
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TTFN (ta ta for now)
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I do not agree that low pressure in Apollo 13 had anything to do with feeling cold or overall comfort. Gas thermal conductivity is practically independent of pressure, and convective heat transfer increases with pressure. Air is 20% O2 and 15/5=3 psi. So on Earth we have a partial pressure of O2 of 3 psi. So in Space we are perfectly comfortable in a pure 3 psi atmosphere. The earlier Apollo fire was caused by using pure O2 at 15 psi at ground level.

Nitrogen and carbon needed for life are recycled pretty effectively. It is not necessary to mine these.
 
"Where is the... ...Nitrogen and Carbon...?"

I think I've found them...

------> [flush3]

 
Hmmmm...

I am unconvinced about general 'don't worry' response to my basic premise... I 'sense' obtaining other elements at these locations may ultimately be more difficult than expected.

CP... I'm mulling-over Your response... Unsure, especially in-terms of the confines of the Apollo 13 CM on that particular mission. Low atmospheric pressure/mass [and reduced cabin airflow/heating and moisture removal] means that humidity/moisture [IE: from sweat and breathing] build-up would also have been a contributing factor to being cold

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
There are so many deficiencies that build up during prolonged spaceflight, I doubt we've counted them all yet.

You can go without air... for a few minutes
You can go without water... for a few days
You can go without heat... for a few hours
You can go without food... for a few weeks

But that's just survival - hardly a recipe to thrive on.

And then of course there are the extras that we get, but don't want, like cosmic rays, and confinement. Put down on a surface like Mars, Moon, or a 'Roid, and there's plenty of abrasive dust kicking around now, too. And then there is never being able to get more than 4 meters away from the guy humming the same tune over and over...

I see no way around this: humans will have to haul up enough material (dirt and plants) to make a self-sustaining biosphere, wherever we try to set up shop. Converting regolith/areolith into soil may take many generations, unless some kind of breakthrough is found. There will be a lot of surprises along the way, not all of them pleasant.

(I'd still accept in a hearbeat, if offered a ticket to go)

 
"Converting regolith/areolith into soil may take many generations" … c'mon, Matt the Martian did it in less than an hour !

another day in paradise, or is paradise one day closer ?
 
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