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#151 2016-12-04 20:13:46

knightdepaix
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Registered: 2014-07-07
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Re: Mars Needs Nitrogen

Quick question: can the CNO cycle be imitated and stopped after producing nitrogen-14 from carbon-12? Carbon-12 shall be abundant from Martian atmosphere anyway.

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#152 2016-12-04 20:31:46

RobertDyck
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Re: Mars Needs Nitrogen

You could draw off come gas from the reactor, run it through a mass spectrometer to separate out N-14, direct the rest back into the reactor. But operating a nuclear reactor just to make nitrogen is very expensive. I still suspect vast buried beds of nitrate somewhere.

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#153 2016-12-04 20:58:13

Tom Kalbfus
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Re: Mars Needs Nitrogen

What is the best source of Nitrogen for Mars? Is it Titan?

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#154 2016-12-05 05:55:20

Terraformer
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Re: Mars Needs Nitrogen

It depends on how much nitrogen Mars has, and what you're trying to accomplish. Plants don't need anywhere near as much nitrogen as is available in the Terran atmosphere (see: the Minimal Martian Terraformed Atmosphere thread). It may be that Mars has enough nitrates to provide for plants, though it's very unlikely to be enough for an Earth-like atmosphere of 0.78 bars nitrogen.


Use what is abundant and build to last

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#155 2016-12-05 08:35:41

Tom Kalbfus
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Re: Mars Needs Nitrogen

How many examples of earthlike planets do we have other than earth? Also Mars is going to need a thick atmosphere to provide for a greenhouse effect, the gas used to bulk up Mars' atmosphere can't be oxygen, you are not going to want to have 1 bar of oxygen, it can't be carbon-dioxide, as too much carbon dioxide would be toxic to us. Nitrogen s what we evolved under, so Nitrogen is what we'll have to get. Pluto has nitrogen as well, but maybe it is more convenient to obtain it from an atmosphere rather than the ground.

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#156 2016-12-05 09:07:55

elderflower
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Re: Mars Needs Nitrogen

Mars also has Argon in similar quantities to Nitrogen so I expect we will have a mixture of the two, with Oxygen, for breathing. Outside there will need to be a relatively high concentration of things like sulphur hexafluoride, hexafluoroethane, and tetrafluoromethane to give the necessary warming.

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#157 2016-12-05 10:38:03

knightdepaix
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Registered: 2014-07-07
Posts: 239

Re: Mars Needs Nitrogen

http://www.gwadi.org/tools/tracers/beryllium

Beryllium-10, half-life of 1.6 million years, is made from
1) high-energy proton component in cosmic radiation, causing spallation of atmospheric oxygen atoms
2) Be-10 is also produced at the surface of the earth by direct cosmic ray irradiation of target atoms in geologic materials. In quartz, Be-10 is produced by spallation from the interaction of cosmic rays with oxygen and silicon and by negative mu-meson capture of Si-28.

So purely on paper, one could stay geological material of quartz and silicon dioxide, which are likely metallurgical residue on Mars (or the Moon for that matter), onto the space where the cosmic rays are most intense near Mars. Then once in many years, maybe decades or more, exchange the exposed "SiO2 rock" with a new target. The collected "SiO2 rock", now mostly Be-10 on the surface facing the cosmic rays, is processed to extract Be-10. Because of its million years half-life, radiation loss of Be-10 shall be negligible. In a nuclear reactor, Be-10 is bombarded by helium-4, which could be byproduct of some other reactor or mining, into carbon-14. Then the familiar reaction of C-14 into N-14.

The major drawback is the process may take many decades to be accomplished yet terraforming cannot wait, not to mention Beryllium is toxic to human. Even though robotic or automatic process could dodge the toxicity during processing, the obviously constrain is that the half-life of C-14 is 5700+-30 years, so you need 57 centuries to get half your intended composition of atmosphere to fill with nitrogen.

Or can decay reaction be accelerated ?

Last edited by knightdepaix (2016-12-05 10:42:27)

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#158 2016-12-05 11:29:39

Tom Kalbfus
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Re: Mars Needs Nitrogen

I'm confused, what do you need Beryllium-10 for? To make nitrogen? Might it be easier just to import some from Titan? What if we packaged frozen Nitrogen within a sphere of water ice and sent it on a collision course with Mars?

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#159 2016-12-05 12:08:43

Antius
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From: Cumbria, UK
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Posts: 1,003

Re: Mars Needs Nitrogen

I would forget about making nitrogen using nucleosynethis.  A 1-GWe fusion reactor will burn through about 100kg of fuel per year.  To make enough nitrogen from other elements to make up for Mars' shortfall in a timescale that matters to human beings, would release enough energy to melt the planet.  Good luck affording it too.  Oh and by the way, the sharp reduction in binding energy for elements beyond helium would make synthesis of nitrogen a very difficult task for fusion reactors.  Kind of like trying to heat your house by burning wet grass.

Importing nitrogen from other planets is at least technically achievable.  But we are talking a lot of material, like moving a sizable chunk of the mass of Earth's atmosphere from Titan or some other body to Mars.  Whether that will ever be affordable is an open question.  And you would be paying huge sums of money for something that might improve the planet's habitability centuries hence.  Kind of like the challenge we face with mitigating global warming today.  And likely to face the same kind of problems.  No one wants to pay for it.

Last edited by Antius (2016-12-05 12:15:47)

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#160 2016-12-05 13:35:52

Tom Kalbfus
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Re: Mars Needs Nitrogen

Antius wrote:

I would forget about making nitrogen using nucleosynethis.  A 1-GWe fusion reactor will burn through about 100kg of fuel per year.  To make enough nitrogen from other elements to make up for Mars' shortfall in a timescale that matters to human beings, would release enough energy to melt the planet.  Good luck affording it too.  Oh and by the way, the sharp reduction in binding energy for elements beyond helium would make synthesis of nitrogen a very difficult task for fusion reactors.  Kind of like trying to heat your house by burning wet grass.

Importing nitrogen from other planets is at least technically achievable.  But we are talking a lot of material, like moving a sizable chunk of the mass of Earth's atmosphere from Titan or some other body to Mars.  Whether that will ever be affordable is an open question.  And you would be paying huge sums of money for something that might improve the planet's habitability centuries hence.  Kind of like the challenge we face with mitigating global warming today.  And likely to face the same kind of problems.  No one wants to pay for it.

What's the challenge to global warming? All we have to do is block sunlight!
thoth-tower-600x381.jpg
remember these? These towers were to be 20 kilometer high, which is above most of the weather. What if we built a bunch of these at even interval all over the planet, just as I suggested for Venus, and created clouds over the Earth to reflect sunlight back into space? That ought to cool the planet! But as I look out my window, it just snowed, it doesn't seem to be getting substantially warmer, so I think the need to construct these towers all over the planet isn't there yet, but just remember we could if we have to, we might not need to, so I suggest we don't impoverish ourselves with drastic measures to combat global warming that might not work, such as deindustrialization to reduce carbon-dioxide emissions. if Global Warming is happening anyway, we might still need to build those towers, making ourselves poor is not he way to get ready for that.

As for Transporting nitrogen off of Titan, its a lot easier than getting it off of Venus. The escape velocity for Titan is 8,658 feet/s (2,639 m/s), the escape velocity for Venus is 33,793 feet/s (10,300 m/s), you need 15.7 times the energy to accelerate a given amount of mass to Venus escape velocity as you do from Titan, That means for every kilogram of nitrogen you lift out of Venus, you could hurl almost 16 kilograms out of Titan.

Titan has an average orbital velocity of 5.57 km/sec at a distance of 1221870 km, Saturn has a radius of 58,232 km and a mass of 5.6836×10^26 kg, The gravitational constant is 6.674×10 N⋅m²/kg²
Orbital Speed is Vo=square root(G*m/r) = square root(6.674×10^-11 N⋅m²/kg² * 5.6836×10^26 kg/1.221870*10^9 m)=5571.76 m/sec
Escape velocity is Ve=square root(2*G*m/r) = square root(2*6.674×10^-11 N⋅m²/kg² * 5.6836×10^26 kg/1.221870*10^9 m)=7879.65 m/sec.
The difference is 2307.9 meters per second, adding that to the escape velocity of TItan we get 4946.9 meters per second to escape the combined gravitational influence of both Saturn and Titan, less than half the escape velocity of Venus, So you can get approximately 4 kg off of Titan and free of Saturn's gravitational influence for every 1 kg you can get off of Venus. Orbital speed is 9.69 km/s around the Sun, we need to slow this down so that it falls toward Mars.

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#161 2016-12-05 14:15:32

Antius
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Posts: 1,003

Re: Mars Needs Nitrogen

Tom Kalbfus wrote:

What's the challenge to global warming? All we have to do is block sunlight!

That is kind of the point I was trying to make.  Solving the global warming problem is abount a million times easier than importing an atmosphere to Mars. Yet we don't appear able to do it, even though there are technical solutions.  Basically, human beings cannot look beyond their own noses and stump up the comparatively modest sums of money necessarily to solve this problem.  They would rather lie to themselves and ignore reality.  Apparently, when we move to Mars human beings will become completely different creatures.?

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#162 2016-12-05 15:15:46

elderflower
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Posts: 1,262

Re: Mars Needs Nitrogen

Settlers will not be average humans. They will be selected for useful skills, intelligence and physical condition. It would be a serious problem if numbers of people were sent who could not make important contributions to the settlements. So I think they will be a bit different.

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#163 2016-12-05 16:19:52

Terraformer
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Re: Mars Needs Nitrogen

European-Americans aren't that much different from Europeans. Martians are going to end up no different than the rest of humanity.


Use what is abundant and build to last

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#164 2016-12-05 20:18:21

SpaceNut
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Posts: 29,433

Re: Mars Needs Nitrogen

we are drifting again.....from what amount of nitrogen is really needed. I would do an experiment with regards to bringing some nitrogen to mars in that we can monitor the releasal of it at the surface and watch to see how fast it will escape as there is little point of a gradual build up if its gone before we get to use it...We can also do a ballon carry of some nitrogen to altitudes and do the same release experiment to monitor its escape from that point as well. One we can pin down the rate of escape for build up then we can think about where to get it from.....

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#165 2016-12-05 21:33:43

Tom Kalbfus
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Posts: 4,401

Re: Mars Needs Nitrogen

Antius wrote:
Tom Kalbfus wrote:

What's the challenge to global warming? All we have to do is block sunlight!

That is kind of the point I was trying to make.  Solving the global warming problem is abount a million times easier than importing an atmosphere to Mars. Yet we don't appear able to do it, even though there are technical solutions.  Basically, human beings cannot look beyond their own noses and stump up the comparatively modest sums of money necessarily to solve this problem.  They would rather lie to themselves and ignore reality.  Apparently, when we move to Mars human beings will become completely different creatures.?

One word: Nanotechnology!

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#166 2016-12-05 21:37:39

RobertDyck
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Re: Mars Needs Nitrogen

elderflower wrote:

Mars also has Argon in similar quantities to Nitrogen so I expect we will have a mixture of the two, with Oxygen, for breathing. Outside there will need to be a relatively high concentration of things like sulphur hexafluoride, hexafluoroethane, and tetrafluoromethane to give the necessary warming.

This is absolutely correct. Terraforming gasses are perfluorocarbons, and sulphur hexafluoride. That's CF4, C2F6, C3F8, C4F10, and SF6. Chris McKay suggested chloro-fluoro-carbons (CFCs), but they destroy ozone. You don't want that. Ozone will spontaneously form from oxygen and UV from sunlight. So once you build an oxygen atmosphere, that will form ozone. The trick is don't do something stupid to destroy it. But then look at what elderflower said? It's the same thing. Sulphur hexafluoride = SF6, hexafluoroethane = C2F6, tetrafluoromethane = CF4. The larger molecule perfluorocarbons are minor tweeks, only small quantities if needed.

And Earth is a mixture right now. 0.9% of Earth's atmosphere is argon, so you're breathing a mixture of nitrogen, oxygen, and argon. Earth has 78.084% N2, 20.946% O2, 0.934% Ar, 0.0407% CO2, plus trace gasses.

We probably won't find any geological deposits of argon. But with greenhouse gasses, we don't need 1 atmosphere pressure. We can make do with a lot less. We will need 170 mbar partial pressure O2 minimum; ideal is 200 mbar partial pressure O2. 1 mbar partial pressure CO2 would be 2.5 times what we currently breathe on Earth, but we could easily withstand that. Plants would appreciate the extra CO2. Add current Mars trace gasses (Ne, Xe, Kr), but swamped in the new atmosphere. Perfluorocarbons will tend to float to the upper atmosphere, but SF6 could linger near the surface. But it would most likely be a trace gas. Water is also a trace gas. Would be nice to have a buffer gas to reduce the rate of fire. Would be nice to have total 300 mbar pressure on Mars. Current nitrogen provides 0.189 mbar, and current argon provides 0.112 mbar. So we need something to add roughly 98 mbar partial pressure. Released nitrogen would be nice, but what if there isn't enough on Mars?

On Earth, methane is a trace gas: 0.00018% by volume. Do we produce more? It's a medium greenhouse gas, more powerful than CO2 but not as powerful as perfluorocarbons. Pure methane is colourless and odourless, it doesn't smell like farts. But it's flammable, so you probably don't want more than trace amounts.

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#167 2016-12-05 22:01:03

Tom Kalbfus
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Re: Mars Needs Nitrogen

Methane would probably combust over time, even in trace amounts, it won't stay in an atmosphere that contains substantial amounts of oxygen. You will have to keep on making more! I'd say, maybe we could start with an atmosphere like that and keep on throwing globs of liquid nitrogen at it contained within water ice capsules, and we give it a nice reflective coating, so the Sun won't warm it up and cause it to explode before it impacts Mars. I think nitrogen allows for more permanency, and besides, what good is the nitrogen if it stays on Titan? That is a waste of good nitrogen to be an atmosphere over a frozen world. This leads to an interesting idea for another thread.

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#168 2016-12-05 23:04:14

Void
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Registered: 2011-12-29
Posts: 7,836

Re: Mars Needs Nitrogen

How in the world do you people hope to make it?

Actually, the first thing is to find out what happened to the Nitrogen.

Then how to use what is available.

You may have three ways of dealing with U.V. light and setting up a biosphere.

Ozone.
Methane.
Water ice.

Of these I think Ozone is the least attainable.

As for the utility of Mars, by the time you terraform it to an Ozone supporting atmosphere, the human race will have evolved to something else, or will be dead.

Logic says return it to it's primordial state if you can, as much as you can, that is as much Methane as possible.

And create ice covered reservoirs and inject as much Nitrogen compounds into them as will support a biosphere.  Recover as much Nitrogen from the subsurface as is possible.

If EM drive turns out to be real, then you can make robots go mine Nitrogen from non-Mars sources and bring it back.  (Until the robots replace human kind).

Yes, I can until I can't.


End smile

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#169 2016-12-06 05:13:29

elderflower
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Re: Mars Needs Nitrogen

For breathing we will mix whatever is left after removing CO2 and CO, with sufficient O2 added. So our buffer gas will be Ar and N2 in the proportions found on Mars. It is possible to separate the two, but why would you do that for breathing?
Only if there are no significant reserves of Nitrogen in minerals will we need to import additional buffer gas, and only when we want the planet terraformed, which is a long way in the future. Meantime settlements will be enclosed.

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#170 2016-12-06 05:43:10

Antius
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Re: Mars Needs Nitrogen

If nitrogen importation ever 'takes off' it would be sensible to import it as ammonia.  Aside from the fact that it is easier to transport than compressed nitrogen, you then have a feedstock for nitric acid production and nitrate production for industries on Mars.  Ammonia is a valuable chemical feedstock for all sorts of things and it is something you would need to manufacture on Mars using the Haber process following a process that extracts nitrogen from the atmosphere and combines it with hydrogen gas, which is presumably derived from electrolysis.  Both steps are energy intensive, capital intensive and therefore costly.

If you can mine naturally occurring ammonia on some outer solar system body without having to manufacture it, then it suggests that there may be a way to deliver nitrogen to Mars in a way that would not be an economic black hole.  None of this will happen until Mars has reached a high level of industrialisation and can pay for bulk material imports through exports of finished goods.  So we are talking centuries away.  The most likely sources are icy bodies with relatively shallow gravity wells.  My guess would be Trojans and Centaurs, maybe some of the outer irregular Jovian satellites.

We have discussed previously the possibility of 'Aquaforming' small icy bodies in the outer solar system, using nuclear waste heat to melt them and creating a warm, 1-bar habitable environment at depth.  Outer solar system ice is ~1% ammonia by weight.  In order to use the water for aquaculture, ammonia would need to be removed as it is toxic to marine life.  If this can be accomplished using a low energy intensity membrane process, the aquaformed body would have a surplus of hydrous ammonia that would be available for trade.  Such a small world would (initially) need to import many manufactured goods.  Hence, there may be an opportunity to trade.  If a 50km diameter icy body is 1% ammonia by mass, the amount of ammonia contained within it is 650billion tonnes.  That's about 5kg ammonia per square metre of surface area on Mars.  A hundred such worlds, exporting their ammonia to Mars, would represent a significant atmospheric addition.

Last edited by Antius (2016-12-06 06:48:29)

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#171 2016-12-06 19:47:00

SpaceNut
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Re: Mars Needs Nitrogen

I agree that ammonia would be a good choice to send as we can do electrolysis on the bonds and get the hydrogen to make methane, water and a little oxygen with the help of that martian atmospher and some energy....

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#172 2016-12-30 19:11:44

SpaceNut
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Re: Mars Needs Nitrogen

As posted by

louis wrote:

Since nitrogen has been found on Mars...

https://www.nasa.gov/content/goddard/mars-nitrogen

...looks like we can manufacture uric acid (using water and Mars air as well) if it is really essential to agriculture.

NASA's Curiosity Rover Finds Biologically Useful Nitrogen on Mars at the Gale Crater using the Sample Analysis at Mars (SAM) instrument suite.

The nitrogen was detected in the form of nitric oxide, and could be released from the breakdown of nitrates during heating. Nitrates are a class of molecules that contain nitrogen in a form that can be used by living organisms. Nitrate (NO3) – a nitrogen atom bound to three oxygen atoms – is a source of fixed nitrogen. Along with other nitrogen compounds, the instruments detected nitric oxide (NO -- one atom of nitrogen bound to an oxygen atom) in samples from all three sites. Since nitrate is a nitrogen atom bound to three oxygen atoms, the team thinks most of the NO likely came from nitrate which decomposed as the samples were heated for analysis.

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#173 2017-01-02 19:56:39

knightdepaix
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Registered: 2014-07-07
Posts: 239

Re: Mars Needs Nitrogen

How much nitrogen does Mars has? Having native nitrogen is good, but terraforming for human means more nitrogen, does it?

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#174 2017-01-02 20:19:56

SpaceNut
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From: New Hampshire
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Posts: 29,433

Re: Mars Needs Nitrogen

only went trying to replicate the atmosphere of earth on Mars.... We can do that for the small to large domes but globally we will probably need to import unless we find larger deposits.

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#175 2017-02-20 02:58:54

knightdepaix
Member
Registered: 2014-07-07
Posts: 239

Re: Mars Needs Nitrogen

RobertDyck wrote:

Terraforming gasses are perfluorocarbons, and sulphur hexafluoride. That's CF4, C2F6, C3F8, C4F10, and SF6. chloro-fluoro-carbons (CFCs) destroy ozone. You don't want that. Ozone will spontaneously form from oxygen and UV from sunlight. So once you build an oxygen atmosphere, that will form ozone. The trick is don't do something stupid to destroy it. The larger molecule perfluorocarbons are minor tweeks, only small quantities if needed.

We probably won't find any geological deposits of argon. But with greenhouse gasses, we don't need 1 atmosphere pressure. We can make do with a lot less. We will need 170 mbar partial pressure O2 minimum; ideal is 200 mbar partial pressure O2. 1 mbar partial pressure CO2 would be 2.5 times what we currently breathe on Earth, but we could easily withstand that. Plants would appreciate the extra CO2. Add current Mars trace gasses (Ne, Xe, Kr), but swamped in the new atmosphere. Perfluorocarbons will tend to float to the upper atmosphere, but SF6 could linger near the surface. But it would most likely be a trace gas. Water is also a trace gas. Would be nice to have a buffer gas to reduce the rate of fire. Would be nice to have total 300 mbar pressure on Mars. Current nitrogen provides 0.189 mbar, and current argon provides 0.112 mbar. So we need something to add roughly 98 mbar partial pressure. Released nitrogen would be nice, but what if there isn't enough on Mars?

On Earth, methane is a trace gas: 0.00018% by volume. Do we produce more? It's a medium greenhouse gas, more powerful than CO2 but not as powerful as perfluorocarbons. Pure methane is colourless and odourless, it doesn't smell like farts. But it's flammable, so you probably don't want more than trace amounts.

In terms of elements, oxygen, sulfur, carbon, fluorine, nitrogen are mostly needed. Then Argon, Neon, Xenon, Krypton and hydrogen. Carbon, oxygen, argon are already available; why are Neon, Xenon, Krypton required? Sulfur is going to be available from mining of residues of past volcanic activities, just where to find the ores and not to mention that sulfate is present.

In sum, much more nitrogen is needed -- well, isn't the meaning of this topic title appropriate? Secondly can fluroine be located or made?

My own question is if perfluorohydrocarbons destroy ozone. I believe not.

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