Mars Needs Nitrogen

clark · 2005-02-24 07:27:45

Thanks guys, I'm getting a better apreciation of the problem.

Perhaps questioning where N2 comes from is a bit like asking where Hydrogen comes from- basic elements kind of just "exsist".

Still, in my imagination, there ought to be a way to transmute exsisting elements into Nitrogen based compounds or nitrgoen itself. Perhaps nuclear physics or fusion or some other high intensity energy process is the answer...

Maybe we're thinking about it all wrong too. Nitrogen plays the role of an inert gas, so perhaps there is anlternative gas form that can replace it... not sure what the results on biology would be on an ecosystem that is composed on a non-nitrogen base, but it would seem to be unique.

karov · 2005-02-24 07:58:36

Nitrogen plays the role of an inert gas, so perhaps there is anlternative gas form that can replace it... not sure what the results on biology would be on an ecosystem that is composed on a non-nitrogen base, but it would seem to be unique.

Yes: helium ( too light for the 1/3 gees on Mars), neon - more universaly abundant, but you have to mine it out of the Sun only, argon - narcotic under high pressure, but OK under 500 -1000 miliBars...

karov · 2005-02-24 08:02:36

Artificial mag-field on Mars - Perhubs the best solution is the Zubrin`s one - put a belt of superconducting cable along all the mars` equator and pump it with strong el.currant. Also solves the problem for planet-wide electricity storage and some transport faciliating functions.

REB · 2005-02-24 08:13:39

I would be happy with a partially terriformed Mars. A Mars where the CO2 atmosphere is thick enough for water to exist as a liquid and plants can grow. This would be a Mars where people could walk through Mars forest wearing normal cloths and getting their oxygen from some sort of SCUBA device, or perhaps a device that takes oxygen from the carbon dioxide.

Why I like this approach is because it is something we could start now. As technology and knowledge advances, humans Mars could then go from partial terraformed to fully terraformed.

John Creighton · 2005-02-24 10:14:07

Artificial mag-field on Mars - Perhubs the best solution is the Zubrin`s one - put a belt of superconducting cable along all the mars` equator and pump it with strong el.currant. Also solves the problem for planet-wide electricity storage and some transport faciliating functions.

Why does Zubrin get credit for this one. Show me the original reference. I am sure this idea was discussed on news groups long ago. If anyone famous was to originally propose it it probably would have been Martin Fog or Criss Mckay.

Grypd · 2005-02-24 11:22:24

The reason people want Nitrogen is that it is an inert gas. If we succeed in terraforming we will have an increased atmosphere but if it is just CO2 then the plants we use will break it down into oxygen. It will still mean we cant breathe the atmosphere as there is too much CO2 but it also means we are at real risk of fire as Oxygen concentrations if too high create a real risk of uncontrollable blazes.

Earthfirst · 2005-02-24 11:50:25

To Clark: Making fun of me for knowing more about N cycle is very strange. I was just correcting some people who fought that Gene mod. bacteria would needed to break down nitrates down into free N2. No modify bacteria are needed for this because they all ready exist. Eating nitrates gives almost the same amount of energy as does 02 in the electron transport chain of metabolism. With a gene mod humans could use nitrates instead of O2 for food, but insteated of breathing it in as a gas we absorbe in a dissolved from through are lungs.

clark · 2005-02-24 15:26:59

Earthfirst, all apologies. I was just a bit surprised at your rather informed opinion given some of your other posts. A Gang'sta down wit da veggies.

I don't think N2 gene modification will replace the role oxygen plays in our bodies. We would have to eat constantly, no?

So, where does Nitrogen originate from? I understand the cycle formation/breakdown. I want to know from whence it came.

chat · 2005-02-24 16:35:07

Shaun,

Higher than normal amounts of UV plants and animal life can adapt to, such as high elevations on earth.

But on mars the problem is not just UV at 50X earth levels, but gama rays, x rays, cosmic rays, charged particles etc that mars blocks little to none.

All of those radiations are life destroying, on earth most are deflected by the magnetic field.
Increase those sets or radiation even 1% or 2% on earth and the extinctions and mutations would be massive, maybe even global extinction for everything.

A thicker atmosphere on mars will help a lot with UV but little with the rest.

We can probably engineer bacteria to do some of the work to steer mars to a new direction, but first it will have to be safe enough for the bacteria to live long enough to do something.

Warming mars then making it a radiation safe place might be the first 2 mandatory steps to teraforming.

Reb,
I agree..

Making mars a safer place to begin with, then set up shop on mars to complete it sounds like the way to go.

The colonist can complete the place as they see fit.

In the final outcome mars might resist any change we attempt, the colonist might have to learn to live with mars as is.

That is not such a bad thing as I'm sure mars is already a spectacular place as is.

karov,

Not a bad plan at all.
Highway, electricity and magnetic field all rolled into one.

Rxke · 2005-02-24 16:37:09

re: Clark-Where does N come from?

Stardust.

we're all stardust. Everything we see around us is made up from stardust.
Every element has been made from fusion processes inside long since disappeared stars, eons and eons ago.

(Is that what you mean or...)

chat · 2005-02-24 16:44:12

Grypd,

Bacteria will be able to fix the current nitrogen levels with plants on a warm wet mars, it might require a genetic boost to the nitrogen fixing family of bacteria to make it work well on mars.

I might be wrong here but i believe for combustion of 02 we need an atmosphere at 34% 02.
Probably not a big worry we would ever convert that much c02 into c and o2 on mars.

chat · 2005-02-24 16:46:18

Rxke,

Who's been taking the quarters from under my pillows then?
I long believed it was the nitrogen fairy, but now i have my doubts.

Grypd · 2005-02-24 18:15:38

Grypd,
Bacteria will be able to fix the current nitrogen levels with plants on a warm wet mars, it might require a genetic boost to the nitrogen fixing family of bacteria to make it work well on mars.
I might be wrong here but i believe for combustion of 02 we need an atmosphere at 34% 02.
Probably not a big worry we would ever convert that much c02 into c and o2 on mars.

Actually the atmosphere we have has an oxygen atmosphere of 21% every percent over that is an increasing risk of fire. By the time we reach an atmosphere content of 30% a fire will be so hard to fight that it will be a knightmare.

We have to remember that fires on Earth is what is one of the main means the planet has for keeping the oxygen atmosphere we breathe at its level. It also helps produce the Ozone that protects us. But on a Mars where we are not breathing and consuming the oxygen that is converted by plantlife will allow oxygen levels to rise quickly. It will come down when we have fires but will get up again very quickly. This means that we will find fires being an incredible risk to the population we have on Mars.

The best way would be to have an atmosphere similar to Earths even if of a lower pressure as we can introduce wildlife that will like us remove the excess oxygen and create a reasonable balance. Nitrogen is the key, it being a neutral gas is simply essential to allow us to have a proper biosphere.

Shaun Barrett · 2005-02-24 19:54:57

Hi Chat:-

But on mars the problem is not just UV at 50X earth levels, but gama rays, x rays, cosmic rays, charged particles etc that mars blocks little to none.

The question we're dealing with relates to the environment on Mars after full terraforming has been achieved. Full terraforming, in most people's minds, involves the creation of an atmosphere which allows humans to roam freely on the surface without the need for a pressure suit or respirator.
Obviously, the ideal situation would be to create an atmosphere just like Earth's: 1013 millibars at sea-level, consisting of 78% N2, 21% O2, 0.9% Argon, 0.03% CO2, plus trace gases.

However, there's no guarantee that the volatiles we would need to do this are available in sufficient quantity. As a result, it appears most people would be satisfied if we could create 'half an atmosphere', which is to say a surface pressure of about 500 millibars.

To provide the same partial pressure of oxygen we enjoy here on Earth, i.e. roughly 210 millibars, it's clear from the figures that we need to enrich our 500 millibar atmosphere to 40% O2. So, we end up with air which is about 40% O2 and 60% N2, assuming we ever find that much nitrogen somewhere on Mars! Again, this brings us back to the fabled nitrate beds and the denitrifying bacteria Earthfirst has been talking to Clark about.

But the point I've been trying to make is to compare this new 500 millibar O2/N2 atmosphere with the closest equivalent we have here on Earth, in an attempt to show that the environment on a fully terraformed Mars is, in fact, quite liveable for not only plants but humans. This is why I searched for inhabited regions of Earth at an altitude of 5600 metres, which gives us broadly the same ambient pressure as we'd have on our new Mars.
And, sure enough, I discovered that 7000 people live at La Rinconada in Peru at an altitude of 5100 metres, where the pressure is about 530 millibars. Interestingly, the partial pressure of O2 at this altitude must be little more than 110 millibars, only half of the oxygen partial pressure our new Martians will experience at sea-level on Mars. And yet people have lived and reproduced under these adverse conditions in La Rinconada for 40 years - a testament to the adaptability of our species and perhaps a portent of how humans may change very quickly to adapt to life on Mars.

When we've created the oxygen-rich atmosphere we're talking about, an ozone layer will form in the Martian stratosphere and reduce UV levels to no more than those experienced on Earth - almost certainly less, in fact, because of the O2 enrichment I mentioned, and because Mars is roughly 75 million kilometres further from the Sun (insolation being only 43% of that at Earth's distance).

Gamma Rays and X-Rays are electromagnetic radiation, just like visible light. Such radiation is unaffected by magnetic fields. This means the lack of a global magnetic field on Mars makes no difference to the influx of this radiation - and in fact, our terraformed Martian surface will get no more of it than La Rinconada gets.

Galactic Cosmic Rays are essentially atomic nuclei travelling at relativistic velocities. The lower energy Cosmic Rays are affected by the Sun's and Earth's magnetic fields and are largely stopped by a blanketing atmosphere. The heavier high-speed nuclei, while deflected by our magnetic field, still reach Earth's atmosphere. On the way through the atmosphere, many collide with atoms and produce a cascade of secondary particles, attenuating their penetrating power. But still, many reach the surface and this hasn't made life untenable on Earth.
The Sun's magnetic field (and possibly Mars' scattered, 'fossil', crustal magnetic field) plus the 500 millibar atmosphere we propose to create, will stop all but the higher-energy Cosmic Rays. These will reach the surface of Mars in greater numbers than they do here but very probably not in show-stopping numbers.
Experiments show that the number of Cosmic Rays penetrating Earth's atmosphere at the altitude of La Rinconada, is roughly double the number reaching sea-level. The number of high-energy Cosmic Rays reaching sea-level on a terraformed Mars is yet to be calculated, as far as I know, but I suspect it won't be dangerously higher than at La Rinconada.

We should remember that roughly every 250,000 years Earth's magnetic field reduces to zero as it undergoes a polarity change. This has happened countless times throughout Earth's history and yet there's no evidence that this periodic 'lowering of the shields' has had any detrimental effect on terrestrial life.
This is a telling indicator that Earth's atmosphere is much more important in protecting life on the surface from both Galactic Cosmic Rays and the Solar Wind particles than its magnetic field.

I think it's inevitable that there will be a generally higher level of ionizing radiation on a terraformed Mars but I don't believe it will be anywhere near high enough to affect the viability of surface life. One consequence might be accelerated evolution through the agency of more frequent mutations - and this in itself will probably lead to the evolution of more radiation-hardened organisms, given time.
I certainly don't agree with you, Chat, that plant life will be unable to survive on the surface of our new world; I think your analysis is way too pessimistic.

chat · 2005-02-25 06:01:24

Hi Shaun,

I agree that since Mars is further from the sun, that initial radiation levels from the sun will be lower, so a smaller atmosphere should produce the same protection as on earth.

I didn't want to sound to pessimistic on my thinking about mars, but someone should really sit down and do the numbers and see what a semi terafored Mars is like for radiation and solar flares.

Right now mars is a pretty nasty radiation zone.

Getting around the radiation problem isn't to hard on a local level, as colonists can set up a few mile wide magnetic field to decrease most of the charged particles form the local area.

In my opinion i think Mars is a place that can be semi teraformed over many centuries, or with one well picked and placed impactor, i just question as to why since it already has everything we need as it is.

I think you are also correct about mutations on mars being at much higher levels than on earth.
Even if we can control the extra radiation on mars the counts will be higher than on earth, so mutations will be frequent.

Good point about the earths magnetic field switching every 25,000 years or so.
All the info right now seems to point to the fact that we are about to experience that in the near future.

This magnetic flip flop might be the reason earth is such a diversified place of life, as the field weakens mutations increase and new species are started.

It makes me think that mars might be a zoo of new creatures, mars life might be very adaptive.
Simple bacteria might mutate so fast that the mutated bacteria sets up home where we don't expect, doing things we don't expect.

I guess the extra nitrogen for mars is more of a extra nitrogen for humans and animal life question.
Does mars need more nitrogen? or do humans need more nitrogen on mars?

Shaun Barrett · 2005-02-25 08:00:36

Grypd Quote:-
"Actually the atmosphere we have has an oxygen atmosphere of 21% every percent over that is an increasing risk of fire. By the time we reach an atmosphere content of 30% a fire will be so hard to fight that it will be a nightmare."

This is an interesting point and I've often wondered at just what percentage of oxygen spontaneous combustion becomes a problem.
Apparently, oxygen levels in Earth's atmosphere have been much higher in the past than they are now, as described in this excerpt from a paper called "Atmospheric oxygen, giant paleozoic insects and the evolution of aerial locomotor performance", published on the 24th March 1998 :-

"Concomitant with this reduction in carbon dioxide
concentration, the oxygen concentration of the late Paleozoic atmosphere may have risen to as high as 35 % (Berner and Canfield, 1989; see Fig. 1), a remarkable value compared with the 20.9 % of the contemporary atmosphere.This elevation of oxygen partial pressure occurred against the background of a constant nitrogen partial pressure (Hart, 1978; Holland, 1984), yielding an increased total pressure of the atmosphere.
Atmospheric oxygen concentrations are unlikely to have
exceeded 35 %, as this value represents an approximate threshold for spontaneous combustion of the biosphere (Watson et al. 1978; Kump, 1989). "

It's interesting to consider that, while the oxygen level changes, the partial pressures of inert nitrogen and argon in the atmosphere remain constant.
I did a little arithmetic and found that if the partial pressure of O2 reaches 35%, leaving the partial pressures of nitrogen and argon at about 780 and 9 millibars respectively, then Earth's sea-level pressure must have been roughly 1213 millibars, or about 200 millibars higher than today's figure. And the partial pressure of O2 would have been about 424 millibars - or double today's partial pressure!

According to the paper I've quoted then, 424 millibars of O2 in a total atmosphere of 1213 millibars is regarded as the threshold for spontaneous combustion of the biosphere.
But does spontaneous combustion depend solely on the percentage of O2, in this case 35%, or does the total pressure influence the threshold?
In other words, can anyone tell me whether 35% O2 is still the threshold of spontaneous combustion in an N2/O2 atmosphere totalling only 500 millibars.

My instinct is that the lower the total pressure of an N2/O2 atmosphere, the higher the O2 percentage-threshold of spontaneous combustion becomes. This means that you could have a Martian atmosphere of 40% O2 and 60% N2 (plus trace gases of course) without fear of spontaneous combustion because the total pressure is relatively low.
Is this correct? ???

el scorcho · 2005-02-26 00:40:20

I've been thinking about this for quite a while, and a thought occurred to me that I haven't heard anyone mention before. I don't know if it has been mentioned here, but if so, bear with me; I shan't be long.

We extract nitrogen in the form of NH3 from the digestion of proteins, and if it is not used to build tissue, it is expelled from the body in the form of urine. Since there will probably be a good deal of water recycling going on in the first colonies anyway, why not harvest the colonists' urine in refinement facilities--no different than your local water treatment plant--and extract the NH3? The nitrogen could be used to create a nitrogen-rich internal atmosphere within the pressurized domes and, once the atmosphere has been thickened, colonies all across the planet could actually release quantities of N2 into the atmosphere--perhaps at the same facilities where CFCs are released.

It's quite late and I'm tired, so my chemistry may be a little off, but if you factor in the atmospheric CO2 (in the earlier stages of settlement), it should look something like this:

2NH3 + 2CO2 --> N2 + CH4 + H2O + O3 + C2

with the N2 being pumped into the colony's internal environment or stored in tanks for later release into the atmosphere. The CH4 is stored as propellant for rockets while the H2O is put to its obvious uses and the O3 is either broken back down into O2 for breathing oxygen or as bipropellant with the CH4, or it is kept in the form of O3 and used to thicken the Martian ozone layer. The C2 can be used to construct high-strength nanotubes for construction projects--maybe even those as grandiose as a space elevator.

But it is late and I am tired, so I'm going to bed and yall can have all night to tear my post apart. :laugh:

Shaun Barrett · 2005-02-26 01:38:22

Hi El Scorcho!
I have serious reservations about your plan.

There's protein in our food, and nitrogen in the protein, as you've quite rightly stated. And, if we eat the protein and don't utilize all of the constituents, we excrete nitrogen in the form of urea.
So, there's no reason why we shouldn't be able to obtain nitrogen from urine.
But where did the nitrogen in our food come from in the first place?

Nitrogen in our food can only have come from the environment in which we grow that food. In a closed system, like domes on Mars, we can't produce excess nitrogen out of nowhere. If we get nitrogen from our urine and pump it into the dome's atmosphere, it will simply be recycled into our food so that we can eat it again.

Unless I'm misunderstanding something here, your scheme seems to be rather like the magician's trick with the rabbit and the hat. Except you're producing enough rabbits to populate the whole of Mars - or, in this case, enough nitrogen to build a planetary atmosphere.

I don't think it's going to work.

karov · 2005-02-26 05:55:44

Artificial mag-field on Mars - Perhubs the best solution is the Zubrin`s one - put a belt of superconducting cable along all the mars` equator and pump it with strong el.currant. Also solves the problem for planet-wide electricity storage and some transport faciliating functions.
Why does Zubrin get credit for this one. Show me the original reference. I am sure this idea was discussed on news groups long ago. If anyone famous was to originally propose it it probably would have been Martin Fog or Criss Mckay.

27.06.2004
Quote (atitarev @ June 27 2004, 00:30)
EDIT:

Here's his answer:

Quote
... Concerning terraforming smaller bodies, one idea that I may have not thrown
in SGIS is that it would be useful for atmosphere retention if they had their
own magnetic field. Looking back to Zubrin and Andrew's Analog article on
magnetic sails (1990 or so?), the equations they present could be applied to an
equatorial superconducting pipeline around a small body--Trans Siberian railroad
scale engineering. The field so generated would create an artificial
magnetosphere around the body and keep the solar wind from blowing the atmosphere
away. It would also, of course, double as a power distribution system. ;-) ...

karov · 2005-02-26 05:59:09

karov,
Wouldn't one nitrogen rich asteroid or comet impacting mars on the pole solve all the problems?
To me this seems to resolve all the Martian climate at once (well other than the radiation problem).

Perhubs, but the centrifugal effect of the Titan`s orbital motion, harnessed via orbital tower of plain and simple material and turbines, gives you simultaneously - the material - N2, asnd the energy sourse to process it and to hawl it towards Mars. Plus, the material for the L-N2 tanks ( the >6% CH4 content for plastic and buckies)...

karov · 2005-02-26 09:16:36

Excuse me, it just occured to me that the quoted posting of Atitarev is indeed re-quoted by him part of personal e-mail exchange with Gerald Nordley -- so G.Nordley is the inventor of the superconductive equatorial belt, inspireed on his turn from the 1992 work of Zubrin and Andrew on the mag-sails...

By the way - this is elaboration and improvement of other design - just put the planet in the center of huge mag-sail. Indeed to build it on ground is much more simpler for construction and maintainance...

Dook · 2005-02-26 10:46:18

I hate the idea of taking material from one planetary body to terraform another but it may be the only way to get enough nitrogen on mars. Where to get it from is another question.

Liquid nitrogen expansion ration 696 to 1 part gas
-321 degrees F is boiling point
Liquid weight 50.45 lb/scf

A cargo ship with a 10' by 10' and 100' long insulated storage tank could carry 504,500 lbs of liquid nitrogen. If sent to mars this liquid would become 351,132,000 scf of nitrogen gas. Is this enough to do anything? How many more of these would we need?

karov · 2005-02-26 12:10:38

Dook,

We have about 3.8 exp 15 tonnes of N2 in earth`s atmosphere.

So, if we assume ~300 milibars of N2 ( or even less 250 milibars of N2 ~1/3 the earth`s one) for Mars + ~200 milibars of O2 ( or even 100-150 milibars of O2 , which are absolutely tolerable by standard humans` organisms for full-life cycle habitation as the upper Andes` example quotes), or totally about 400 milibars ( 250 N2/150 O2) - than under 1/3th gees and with 1/3th earths planetary surface - we`d need 1/3th of the earth`s nitrogen quantity imported on Mars: i.e. 1.27 exp 15 tonnes.

Your half a million lbs, should mean about 250 metric tonnes for each shipping tank. Say, 1270 tonnes per each delivery unit cargo, gives us ONE TRILLION ships. Not so much!!!

The N2 could be shipped as pieces of solid N2 ice, kept in shade of solar sail -- drive for leaving Saturn`s orbit and directing to collision course with Mars...

Dook · 2005-02-26 12:25:39

Only 1 trillion huh?

RobS · 2005-02-26 12:35:08

Regarding the masses of gas needed for creating a dense atmosphere, think of the problem this way:

1. The earth's atmosphere has about 10 tonnes of gas above every single square meter of the planet's surface. That's the mass necessary to produce a pressure of 1000 millibars (1 bar, which equals 10 tonnes per square meter).

2. On Mars, with 0.38 gravity (rounded here to 0.4 for convenience), one would need about 25 tonnes per square meter to produce the same pressure (because pressure is mass per square meter times gravity).

3. Mars has about 125 million square kilometers and a square kilometer has 1 million square meters, so Mars has a surface area of 125 million million (125 trillion) square meters.

4. To produce 10% of a terrestrial atmospheric pressure on Mars, we will need 2.5 tonnes of gas per square meter, or 2.5 x 125 = 312.5 trillion tonnes of gas.

5. To help you visualize the quantity involved, if the gas were condensed to a liquid with the same density as water, it would occupy 312.5 trillion cubic meters, which would require a sphere 7000 meters (7 kilometers) in diameter.

6. I have never heard of such a thing as a "nitrogen rich asteroid" and doubt they exist. I can't imagine any technology able to extract about half the mass of Titan's atmosphere and haul it a billion miles to Mars.

7. Mars has plenty of oxygen; a layer of water 5 meters deep covering the entire planet has enough water to produce an atmospheric pressure of 200 millibars of oxygen. But you'd have to electrolyze the water, then get rid of the hydrogen (probably by "burning" it with Martian regolith, thereby extracting oxygen from the iron and other oxides, reducing them and producing water again). That'd take a helluva lot of energy.

8. The easiest way to terraform Mars is the way the Dutch "terraformed" the Rhine estuaries: one polder at a time. The technology to build domes a kilometer across is much easier to master, and the newly available land is immediately available for resale and recouping the investment. One starts with tens-of-meter scale domes, moves up to hundreds-of-meter scale domes, then moves on to kilometer-scale domes. Mars will see some spectacular engineering in the 22d century, and its people will still enjoy some pretty harsh and spectacular wilderness.

-- RobS

New Mars Forums

Announcement

#26 2005-02-24 07:27:45

Re: Mars Needs Nitrogen

#27 2005-02-24 07:58:36

Re: Mars Needs Nitrogen

#28 2005-02-24 08:02:36

Re: Mars Needs Nitrogen

#29 2005-02-24 08:13:39

Re: Mars Needs Nitrogen

#30 2005-02-24 10:14:07

Re: Mars Needs Nitrogen

#31 2005-02-24 11:22:24

Re: Mars Needs Nitrogen

#32 2005-02-24 11:50:25

Re: Mars Needs Nitrogen

#33 2005-02-24 15:26:59

Re: Mars Needs Nitrogen

#34 2005-02-24 16:35:07

Re: Mars Needs Nitrogen

#35 2005-02-24 16:37:09

Re: Mars Needs Nitrogen

#36 2005-02-24 16:44:12

Re: Mars Needs Nitrogen

#37 2005-02-24 16:46:18

Re: Mars Needs Nitrogen

#38 2005-02-24 18:15:38

Re: Mars Needs Nitrogen

#39 2005-02-24 19:54:57

Re: Mars Needs Nitrogen

#40 2005-02-25 06:01:24

Re: Mars Needs Nitrogen

#41 2005-02-25 08:00:36

Re: Mars Needs Nitrogen

#42 2005-02-26 00:40:20

Re: Mars Needs Nitrogen

#43 2005-02-26 01:38:22

Re: Mars Needs Nitrogen

#44 2005-02-26 05:55:44

Re: Mars Needs Nitrogen

#45 2005-02-26 05:59:09

Re: Mars Needs Nitrogen

#46 2005-02-26 09:16:36

Re: Mars Needs Nitrogen

#47 2005-02-26 10:46:18

Re: Mars Needs Nitrogen

#48 2005-02-26 12:10:38

Re: Mars Needs Nitrogen

#49 2005-02-26 12:25:39

Re: Mars Needs Nitrogen

#50 2005-02-26 12:35:08

Re: Mars Needs Nitrogen

Board footer