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#1 2007-11-16 08:16:11

Terraformer
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From: Ceres
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Are there any powerful green house gasses that are Inert and non-toxic that could be used to terraform the Ice Planets? They could take the place of Nitrogen.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#2 2007-11-16 12:45:05

Midoshi
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From: Colorado
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Much of the fully fluorinated stuff like sulfur hexafluoride (SF6) and tetrafluoromethane (CF4) are not only the most powerful greenhouse gases known, but also among the most inert. Perfluorocarbons (PFCs) in vapor and liquid forms also happen to have the ability to physically (not chemically) absorb oxygen much like hemoglobin. The vapors have been used to improve lung gas exchange in sick animals and oxygenated liquid PFCs have actually been used as an "air substitute", allowing animals submerged in the stuff to breathe and function quite normally. To my knowledge no adverse effects due to toxicity of PFCs used in this way have ever been reported.

Unfortunately for any would be terraformers, sturdy as fluorinated compounds are they do break down after a couple thousand years and need to be replaced through artificial means. Add in the fact that fluorine is much less common than nitrogen, oxygen, etc. and it's clear that getting enough to make a full atmosphere is impractical.

I once entertained the idea that perfluorinated compounds could be made biogenically, but it turns out there's no clear way of doing this. The biological method used to fully halogenate organic compounds is unsuitable for fluorine. And while there is biological machinery to add one fluorine to the end of an organic molecule, it can only add the one. That means there'd still be a lot of relatively weak C-H bonds which would be all too happy to support combustion. That's ok for trace amounts of gas orders of magnitude below the flammability threshold, but I wouldn't be keen on making a large percentage of my atmosphere out of something like that.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#3 2007-11-16 12:55:18

Terraformer
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From: Ceres
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

FC4?

And your sigs wrong.

Science without religion is lame, religion without science is blind.

I believe it's Science without religion is blind, religion without science is lame.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#4 2007-11-16 13:23:12

Midoshi
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From: Colorado
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Posts: 157

Re: Non-Toxic Inert Powerful Greenhouse Gasses

FC4?

And your sigs wrong.

Science without religion is lame, religion without science is blind.

I believe it's Science without religion is blind, religion without science is lame.

FC4? Do you mean tetracarbon monofluoride? I can't say I know a lot about it, but from what I understand it's a solid under standard conditions.

You scared me for a second, but I'm happy to say my sig's correct. You can read the original article it came from here. It's at the end of the fourth paragraph.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#5 2007-11-16 13:35:47

Terraformer
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From: Ceres
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Science without religion is lame, religion without science is blind. That is wrong because that would be saying science without religon can't move forward, and religon without science can but needs science to guide it. That's giving your development over to religon and your morals over to science. That's the worst combo ever. The other way round it's the best.

On that bombshell, back to the topic. It might have been CF4 I was thinking about.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#6 2007-11-16 15:16:04

Midoshi
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From: Colorado
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Posts: 157

Re: Non-Toxic Inert Powerful Greenhouse Gasses

I'll admit I always found the phrasing of that quote somewhat backward myself. I agree with you that people should get their morals and higher goals from religion and their understanding of physical reality from science, and in fact that's exactly what Einstein is saying in that article. Still, a quote's a quote, and if I change it I can no longer say they're Einstein's words. Without the clout of his name I'm afraid people would be less impressed and drawn to actually think about it. And don't worry; I change my sig from time to time, so the offensive phrase won't be around long. (:

Anywho, CF4. Yeah, it's the simplest PFC, basically methane with all the hydrogen replaced with fluorine, and it's both non-flammable and non-toxic. Like nitrogen, its only danger is suffocation. Not technologically hard to make, but you'd need a lot.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#7 2007-11-16 15:19:55

Terraformer
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Is Fluirine relativly rare in the Solar System in asteroids, planets, and the like. I know Carbon isn't.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#8 2007-11-16 15:39:30

Midoshi
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From: Colorado
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Is Fluirine relativly rare in the Solar System in asteroids, planets, and the like. I know Carbon isn't.

Not super rare, but rare enough we can't do much but introduce trace global amounts to any significant planet. There's about 540 ppm fluorine in Earth's crustal rocks by weight, and only 89 ppm in carbonaceous meteorites, which you could take as a proxy for asteroids. The Earth's crust (the lithosphere) is about 2% of its total mass, or about 1e23 kg. That means there's only about 5e19 kg of fluorine that's really accessible on Earth. It's a very rough comparison, but contrast that with the mass of Earth's atmosphere, which is about 5e18 kg. This suggests we'd have to mine approximately 10% of the Earth's crust to get enough fluorine for a serious atmosphere. Even mining 1% would be a phenomenal task; it would be like completely dismantling Ceres, previously considered the largest asteroid.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#9 2007-11-17 07:04:52

Terraformer
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Ceres is a dwaf planet, not an asteroid.

Maybe find an asteroid made of Flurine, get a magnetic field going on an Ice Planet/Moon, crash the asteroid on to it. You'd have an atmosphere nearly 100% Flurine. Introduce 1 Carbon atom from Venus for every 4 Flurine atoms, set the planet on fire, and you have a nice warm planet (after the fire.) Alternitevly you could do it less dramatically and burn Carbon with Flurine for your atmospheric shuttle fuel.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#10 2007-11-17 14:14:58

Midoshi
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From: Colorado
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

True, true, my bad about Ceres. I've amended the offending post.

Finding a "fluorine asteroid" is as impossible as finding an "oxygen asteroid". They're both chemically reactive species and their vast bulk outside of star and supernova plasma is tightly bound up in some sort of mineral. The closest you could possibly get would be an asteroid composed of the mineral fluorite, calcium fluoride (CaF2).

As I'm sure you know, a lot of research is being done on how to liberate oxygen from lunar regolith for the purposes of local breathing gas and rocket oxidant production. This is a very energy intensive process because oxygen bonds so tightly in minerals. Well, fluorine is even worse. Making a whole planetary atmosphere that way would be difficult indeed.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#11 2007-11-17 16:33:20

Austin Stanley
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Well one of the best (if not THE best) greenhouse gases is relativly inert, completely non-toxic, and abundantly common on the ice-plants... water vapor.  Of course the problem is that all the ice giants are to small and to cold for water vapor to exist in any quantity.

In fact, all the planets/moon out past the asteriod belt are probably just to cold and to small for greenhouse gases to have any signifigant effect by there own.  Titan is a perfect case in point.  It thick dense atmosphere is full of greenhouse gases, such as methane, yet the planet itself is still incredibly cold.

Something more beyond just atmospheric manipulation is going to be needed to to terraform the ice worlds.  An added source of heat/light is most likely needed.

FC4?

Can't exist.  Flourine only is only missing one electron in its outer shell and so generally only likes to form a singe bond with any other element.  Carbon on the other hand has 4 valence electrons and 4 open slots and so likes to form 4 bonds with other atoms.


He who refuses to do arithmetic is doomed to talk nonsense.

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#12 2007-11-17 18:22:36

Midoshi
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From: Colorado
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

I took the liberty of crunching the numbers for warming up Pluto to Earth temperature using super-greenhouse gases. I think it is fairly obvious that this would be the easiest known icy dwarf planet to terraform (though that's not saying much). It turns out to be not quite as ridiculous a proposition as one might think, though it is necessary to discard any thoughts of having the GHGs "take the place of Nitrogen".

We assume that we have a thermally grey concoction of GHGs. In order to raise Pluto's average temperature from 50K to an Earth-like 288K would then require enough GHGs to produce a thermal optical thickness of 600. Using fluorinated super GHGs this is equivalent to a molecular column of ~1e25 m^-2 or a surface GHG pressure of ~5 microbar. Dwarf planets further out than Pluto would typically require more GHGs. Compare this to Mars, which would require an optical thickness of 3, a molecular column of 5e22 m^-2, and a surface GHG pressure of 0.1 microbar to produce a similar warming effect. I refer you to "Keeping Mars warm with new super greenhouse gases" (Gerstell et al. 2001) for details.

There is much evidence that the surfaces of Pluto, Triton, and similar trans-Neptunian objects are coated with significant amounts of nitrogen ice. This would be released to form an atmosphere as the body was warmed. Unfortunately, just how much nitrogen ice is on Pluto (or any of these bodies) is very poorly constrained; the current lower and upper limits for average surface thickness are of order 10 cm and 1 km respectively. More info is available in "Seasonal Nitrogen Cycles on Pluto" (Hansen and Paige 1996). If there is about 100 m of nitrogen ice on Pluto a 1000 mbar atmosphere much like that of early Earth would be produced. Significant amounts of ammonia, carbon dioxide, methane, and water vapor might also be present, but these would have small effects on atmospheric pressure and be virtually negligible in terms of contributing to the greenhouse effect already produced by the super GHGs. Due to the high ice content of the planets in question, the system would become a "waterworld" with a rocky core as the body thawed over millenia.

The biggest problem with the whole idea is where to get a large supply of fluorine to produce the super GHGs. The existence of fluorine on icy dwarf planets is pure speculation, and expecting significant amounts is pretty much fantasy. On the order of 1e14 kg of calcium fluoride ore would be needed to initially warm Pluto. At the current global fluorite mining rate on Earth (~5 million metric tons per year) it would take 20 millenia to produce that. Unfortunately, Earth's known fluorite and fluorite equivalent phosphate resources are less than 1e12 kg. You'd need to find 100 times more fluorite, either on Earth where we don't have mines yet or on an extraterrestrial body. On the bright side, once you had built up your initial GHG levels your replacement rate would be very low. This is because UV strength and solar wind density, which dominate super GHG destruction rates, are miniscule at Pluto's orbit.

A problem I'm not sure of the answer to is making the fluorinated super GHGs vaporous when beginning; all of them are solid at Pluto's current temperature. Their vapor pressures may be sufficient to get things rolling, but some initial external heating may be necessary as Austin Stanley suggested.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#13 2007-11-18 02:52:13

Terraformer
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Well one of the best (if not THE best) greenhouse gases is relativly inert, completely non-toxic, and abundantly common on the ice-plants... water vapor.  Of course the problem is that all the ice giants are to small and to cold for water vapor to exist in any quantity.

Wouldn't work. I thought about it to. See my thread "Water Vapor in Place of Nitrogen". The vapor would condense out of the atmosphere above a certain amount.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#14 2008-01-18 14:25:14

qraal
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From: Brisbane, Australia
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Re: Non-Toxic Inert Powerful Greenhouse Gasses

Hi All

Hydrogen and methane are both greenhouse gases and above a certain mixing ratio they're non-flammable when oxygen is around - though we're talking 10 bar pressure for the mix to be breathable.

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#15 2008-01-19 23:44:17

Midoshi
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From: Colorado
Registered: 2007-07-14
Posts: 157

Re: Non-Toxic Inert Powerful Greenhouse Gasses

Hi All

Hydrogen and methane are both greenhouse gases and above a certain mixing ratio they're non-flammable when oxygen is around - though we're talking 10 bar pressure for the mix to be breathable.

I considered this myself a while back and came to the conclusion that it was a beautiful idea...except for two things:

#1 Both methane/hydrogen are very light molecules that won't get caught in a cold trap. Most/all of their components are hydrogen, so once they get to altitudes where UV is strong they turn into lots of H which happily drifts off into space. Bye-bye, atmosphere!

#2 If the methane/hydrogen level ever drops to flammable levels through negligence/accident there'd automatically be a horrible global holocaust.

The second problem could be avoided if you were really careful, but there's not much you can do about the first, which is why I eventually abandoned the idea.


"Everything should be made as simple as possible, but no simpler." - Albert Einstein

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#16 2022-08-25 12:03:27

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 6,244

Re: Non-Toxic Inert Powerful Greenhouse Gasses

A pollutant on Earth becomes something that gives Warmth and Life Offworld?

Deepening the Usage of Gas as a Vehicular Fuel
https://www.thisdaylive.com/index.php/2 … ular-fuel/

California expected to issue 2035 ban on sale of new gas cars
https://news.yahoo.com/california-expec … 59996.html

Mars could become a Low Tech manufacturing Hub and all those things classed as Earth pollutants Methyl chloroform, Fluoroform, Sulfur hexafluoride, Nitrogen trifluoride, Difluoromethane, Sulfuryl fluoride, R-114 you the Global Warming Nitrogens or Carbon GHG types that produce warming like CO2 you can dump as much as possible on Mars because it will add a positive livable quality to the planet?

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#17 2022-09-13 03:54:09

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 6,244

Re: Non-Toxic Inert Powerful Greenhouse Gasses

They trade Carbon credits and then tax Carbon, then tax Nitrogen what else will be taxed?

Why scientists have pumped a potent greenhouse gas into streams on public lands
https://www.wabe.org/why-scientists-hav … lic-lands/

The Hank Hill Solution to Climate Change
https://prospect.org/environment/hank-h … te-change/

Some will stay in the air hundreds if not thousands of years Tetrafluoromethane CF4 , Sulfur hexafluoride SF6, Nitrogen trifluoride NF3

and Germany afraid of a Nuclear power solution

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#18 2023-03-17 08:30:41

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 6,244

Re: Non-Toxic Inert Powerful Greenhouse Gasses

Climate change is real and greenhouse gases exist but giving an idiot a little information and a lot of political power can be a bad thing. A lot of carbon in the trees, the grass, the soil, the swamp help pull greenhouses gasses from the air, something with a 'C' a Carbon or an 'N' a Nitrogen is not always bad news.

Warming a world....Take a Comet and land 'Water Vapor' is the non-toxic one a lot of people forget. They want Nitrogen taxed everywhere now even though a lot of the time depending on its chemical compound it can add to global cooling, a Moon that is more like a plantary world Titan you see an 'Antigreenhouse effect' reflecting IR back to space and reduces warming of Saturn's moon. Some other stuff that industry might one day pollute Mars with Carbon dioxide CO2, Perfluorocarbons C2F, Sulfur hexafluoride SF6 and NF3, Tetrafluoromethane CF4, Difluoromethane or HFC-32 Methylene Fluoride or R-32, and 1112-Tetrafluoroethane also known as norflurane also Methane CH4 Nitrous oxide N2O, Ozone O3.

The politics type. Made a mess in Sri Lanka

These Dutch “nitrogen wars” now in Netherlands

Protecting nature, destroying lives: The chemist vs. the Dutch farmers
https://www.politico.eu/article/johan-v … e-farming/

Farmers-led party set to prosper in key Dutch regional elections
https://www.theguardian.com/world/2023/ … transition

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#19 2023-03-17 08:44:37

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 2,619

Re: Non-Toxic Inert Powerful Greenhouse Gasses

Sulphur hexaflouride is the gas with the greatest greenhouse potential.  Sulphur is abundant on Mars and presumably the outer solar system as well.  Flourine is less abundant, but still plentiful enough.  If space manufacturing gets going, we could make GHGs in high Earth orbit.  We deliver it to Mars by putting the tanker on a free return trajectory that just grazes the atmosphere.  Minutes before impact, we release the liquid GHG, which will freeze and then sublime, with the molecules hitting the upper atmosphere.

With Venus we could do the opposite, dumping fine dust into the upper atmosphere, preventing sunlight from reaching the troposphere.  Sieved lunar fines should do the trick.

Water vapour is a greenhouse gas.  We could warm Mars by mounting mass drivers on Ceres.  These would fire packages of ice, contained in aluminium foil opposite to Ceres motion around the sun.  They would be fired with just enough velocity to put them on an elliptical orbit with a perogee that crosses the semi-major axis of Mars.  As they hit the upper atmosphere they would explode and vaporise.  This would super-saturate the upper atmosphere with water vapour and hydroxyl radicals, creating a global warming effect.  As the surface warms and water evaporates, UV light will dissociate it into oxygen, which will accumulate, and hydrogen, which will escape into space.  Eventually, Mars will have atmosphere of almost pure oxygen, with traces of nitrogen, argon and CO2.  An atmospheric pressure 20% of Earth would be enough for people to breath.

There was much discussion a while back about a survey that appeared to show that Mars had insufficient CO2 for terraforming.  However, it is water that will most likely be used to produce the oxygen that humans need for breathing.  Five million cubic km of it has been identified on Mars according to Wiki.  We would only need about one sixth of that to produce a breathable O2 dominated atmosphere.  The process takes care of itself if can keep the planet warm.

Last edited by Calliban (2023-03-17 09:03:59)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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