How far?

noosfractal · 2005-11-05 17:47:55

Only trouble is that the latest information from mars seems to say that most of what is frozen on the poles is water and little frozen co2.
Don't expect much help from frozen co2 if the poles are not packed with it.

I think there is still the expectation of 300 mb of CO2 from the soil. That alone should raise temperatures another 40 K.

Even if enough c02 exists to help rise above the c02 freeze point, it wont be much beyond it, and may make for another problem (co2 freezes planet wide).

But of course, we won't be depending solely on CO2, but also on long-lived super greenhouse gases like C3F8 which are tens of thousands of times more effective than CO2.

You may be right - every greenhouse plan may end in an artic deadend - lots more research is required - but I think you're underestimating how effective greenhouse gases can be.
_

chat · 2005-11-06 05:33:12

noosfractal,

I have no doubt that enough C3F8 would get you past both of the snowball Mars scenarios, the co2 one isn't a giant hurdle anyway as comfortable livable temperatures are much beyond the melt point of co2.
The h20 melt one is a hurdle as comfortable living condition are similar to the melt point.

The trouble with the super greenhouse gasses is the longevity of them after they have done the job required, about 3000 years on earth and probably 1500 years on mars.
When all the c02 is liberated into the atmosphere we get a temperature spike, and same for h20 and other unexpected gasses, but the C3F8 continues at the same rate of heat absorption along with the absorption properties of thicker h2o and co2 atmosphere.

If it was a smooth transition from melt to melt the gas release could easily be stopped, but breaking through the snowball effects will need a lot of C3F8, probably more than is needed for a comfortable teraformed mars.

I would hate to see a Mars go from what it is to a place to warm for human habitation for 1500 years.

I would love to see a simulation of gas quantity needs on a snowball Mars and the after melt temperatures spikes etc.
That would be interesting.

As you pointed out we have no idea what the surface of mars chemistry is when warmed.
Does it act like a sponge or leaky bottle.
Does the peroxide and iron in the surface play any role.
What other chemicals are just under the surface that will contribute to the atmosphere.

Way to many variables to predict, and i agree we need a lot more information about mars to even take an educated guess.

Hope i am wrong about the snowball mars because it is a blow for slow teraforming .
If i am not wrong all we are left with is thump and gas carefully.

Rxke · 2005-11-06 07:05:48

But is the snowball such a big problem? If atmospheric isolation is big enough, it will eventually warm, no matter what albedo... Now heat retention is bad too, at night. If the Snowball happens, a lot of heat will indeed be er-radiated, but even more wil 'stick' in the atmosphere, heating the atmosphere gradually, untill t>0... Or am I completely wrong here?

Dook · 2005-11-06 07:40:38

The earth effectively absorbs a lot of thermal radiation.

http://en.wikipedia.org/wiki/Greenhouse_effect

Rxke · 2005-11-06 07:57:51

Dook, i meant that while surface absorbs quite efficiently, it is a bad heat retainer, because arid (heat a bucket full of dry sand, and one filled with water, the sand cools down very fast., compared to the water... (low caloric whatchacallit... Sometimes I hate it not being English speaking) So it re-radiates almost everything back into the poorly greenhousey atmosphere during the night...
Anyhoo...Me was Very Largely wrong, here, heehee... Snowball: re-radiates solar energy in visible spectrum (mainly) which, AFAIK, no greenhouse gas can block... Still.... Mars will *never* be a complete snowball, due to the sheer height of some places... so these will still... Dang, but they are above the atmosphere, so no greenhouse. (time to remove that caffeine-drip, I'm starting to mutter online)

noosfractal · 2005-11-06 12:54:14

But is the snowball such a big problem? If atmospheric isolation is big enough, it will eventually warm, no matter what albedo... Now heat retention is bad too, at night. If the Snowball happens, a lot of heat will indeed be er-radiated, but even more wil 'stick' in the atmosphere, heating the atmosphere gradually, untill t>0... Or am I completely wrong here?

No, this is right. There are really two things going on. The first is absorbing incoming light from the sun ...

You can see the solar spectrum runs from about 0.2 to 3.0 microns with a peak around 0.5 microns. Visible light is from about 0.4 to 0.7 microns (depending on how good your eyes are Mars gets less than Earth, but the curve is the same shape. Albedo determines how much of this incoming light gets reflected. The albedo of Mars is about 0.25 meaning 25% of the incident energy is reflected and 75% is absorbed (vs. 0.30 for Earth which has clouds).

However, as soon as the energy is absorbed, it starts getting re-radiated as infrared energy ...

You can see that, for Mars, re-radiation occurs at wavelengths greater than 6 microns with a peak near 20 microns - a very different spectrum, so we analyze it separately. The above graph is from Marinova again - it shows why C3F8 is such a good greenhouse gas for Mars - it absorbs over almost the whole re-radiation spectrum. It also shows why water vapor is so important.

With the snowball scenario, albedo would rise, but re-radiation probably wouldn't change dramatically. You're right to say that, with enough greenhouse gases, the snow would eventually melt. I think chat is worried that you would need so much greenhouse gas, that, once the snow did melt and the albedo dropped, then the climate would go from snowball to furnace without stopping to linger in the goldilocks zone. However, he fails to consider that engineers eat this sort of dynamics problem for breakfast before moving on to really difficult stuff. You have to be careful, but we'll be careful.
_

noosfractal · 2005-11-06 13:13:45

I would love to see a simulation of gas quantity needs on a snowball Mars and the after melt temperatures spikes etc.
That would be interesting.

Here is a graph for the snowball Earth hypothesis ...

http://www.cs.caltech.edu/~westside/ge/snowball.html

It uses a pretty simple model that could probably be adapted for Mars.

As you pointed out we have no idea what the surface of mars chemistry is when warmed.
Does it act like a sponge or leaky bottle.
Does the peroxide and iron in the surface play any role.
What other chemicals are just under the surface that will contribute to the atmosphere.
Way to many variables to predict, and i agree we need a lot more information about mars to even take an educated guess.

Yeah, we need to go there and find out
_

Rxke · 2005-11-06 13:22:04

Thanks, noosfractal, I figured it out pretty fast after that post myself. Forgot to take into account the frequencyshift of re-radiation. Quite unforgiveable, if my teachers heard about this, boy... But I was only looking at 'net' energy sums, forgetting about the rest... (laaaaaame excuse) Nice stuff you post, though.

Hm. Another one re: snowball... Initially, when H2O atmospheric release and precipitation occurs, pressure will still be pretty low, how low? Hard to say, CO2 taken into account... But sublimation point will still be pretty low, so... Assuming snow falls at night, at least initially, because otherwise it will be just too warm... Won't the snow sublime, if not melt away during the day?
I'm really thinking we could have a planet fogball for quite awhile... Which isn't bad for keeping the heat in...

And now completely talking out of my a**e: snow is an insulator... If the surface heats up during the day... upper layer cools during the night, but gets isolated pretty quickly by falling snow... Where I live, when winter comes, industrial flower-raisers spray their plants with water, so there's an Ice-layer for insulation when the nights get too cold...
Could this be a scenario naturally occurring, to keep the soil from freezing deep-solid during the nights?

Boyboyboy, Me imagining some super-computer getting a nervous breakdown, trying to simulate this stuff!

Rxke · 2005-11-06 13:25:04

As you pointed out we have no idea what the surface of mars chemistry is when warmed.
Does it act like a sponge or leaky bottle.
Does the peroxide and iron in the surface play any role.
What other chemicals are just under the surface that will contribute to the atmosphere.

We do have one interesting data-point, though: The Viking experiments.

Dook · 2005-11-06 17:58:23

Something I've always wanted to know is how do we manufacture SF6 and C3F8 on mars?

What elements do we need? Sulfate deposits? Flourite?

How do we separate the elements from regolith?

What chemicals are needed and are they used up in the process? If so how do we make these chemicals on mars?

MarsDog · 2005-11-07 02:28:51

Something I've always wanted to know is how do we manufacture SF6 and C3F8 on mars?

http://www.fips.ru/cdfi/fips.dll/en?ty= … 83615&lb=1

distill the required gas and then remix the leftover ?

==========================================

Terraforming trials should begin at the lowest point, Hellas Planitia
http://en.wikipedia.org/wiki/Hellas_basin
http://www.marssociety.pl/geoid.jpg
http://www.adlerplanetarium.org/learn/p … llas02.jpg

Water, higher atmospheric pressure and possibility of placing
solar reflectors on the walls of the crater.

There could even be a localized water and super greenhouse gas cycle.

karov · 2005-11-07 03:13:42

Something I've always wanted to know is how do we manufacture SF6 and C3F8 on mars?
What elements do we need? Sulfate deposits? Flourite?
How do we separate the elements from regolith?
What chemicals are needed and are they used up in the process? If so how do we make these chemicals on mars?

Octafluorpropane ( C3F8 ) is obviously what we need. This imposes the necessity relatively huge amount of fluorine to be implemented. The way to have all this fluorine is hinted in the assumption to extract it from fluorine containing rocks on Mars. Actually M.Maroniva and her team envision exactly this method -- to be built big number of nuclear powered plants which to extract the fluorine, to combine it in C3H8 and to release it in the atmosphere... Rgardless of thee fact whether or not we`ll find enough fluorine in the surface rock leyars of Mars, considering the power necessary to run all this machinery, which to process the rocks, extract the F, etc. etc., we should calculate other two possible sourcs of fluorine:

1. -- the asteroids -- they have not undergone chemical gravitational differentiation, and using just solar power concentrator ovens, small asteroids ( say, <1 km diamater) of the necessary chemical class, could be entirely processed through the distilers and the fluorine to be separated. There is also plenty of carbon up there in the space rocks, so the C3F8, could be produced en situ and than shipped to mars in as small as we find needed packages sent in collision course with Mars, using simple techs like rotational slingshots or else.

2. -- because too huge rough mass of rocks should be in both cases processed in order to have tiny quantities of F eventually, considering the total energy consumption of the business/productional processes: digging , destilation, etc..., we shopuld seriously put into consideration some TRANSMUTATIONAL nuclear fission or fusion process, which to produce in space, using abundant solar power, the necessary quantities of this practically trace element... I`m seriously thinking that the tansmutation may occur to be CHEAPER than mining and chemical separation.
About the origin of the natural fluorine:
http://www.int.washington.edu/talks/Wor … nzio_STAN/

http://www.gemini.edu/index.php?option= … view&id=99

The conditions in the hot cores of these supernovae, could be comperativelly easy mimiced in particle accelerators. In space we have both the necessary vacuum, to built huge accelerators, and the power to run them.

The very general issue of industrial supply of such extremely rare and disperesed substances like fluorine, antimatter, etc..., is quite probably to be solved in this way.

noosfractal · 2005-11-07 04:16:07

Thanks, noosfractal, I figured it out pretty fast after that post myself. Forgot to take into account the frequencyshift of re-radiation. Quite unforgiveable, if my teachers heard about this, boy... But I was only looking at 'net' energy sums, forgetting about the rest... (laaaaaame excuse) Nice stuff you post, though.

Thanks This was originally Siegfried's thread, so I'm still kinda writing for him as well. I think graphs can help a lot sometimes.

H2O atmospheric release and precipitation occurs, pressure will still be pretty low, how low? Hard to say, CO2 taken into account... But sublimation point will still be pretty low, so... Assuming snow falls at night, at least initially, because otherwise it will be just too warm... Won't the snow sublime, if not melt away during the day?

Zubrin's still calling 300 mb of CO2 pressure with a 5-10 K temperature boost. That puts us at global -60° C, so we've still got a ways to go before we have to deal with water vapor. I'm thinking we'll see 600 mb before we see H2O snow. At that pressure, water should behave pretty much as it does on Earth. In fact, the triple point of H2O is 6 mb - about the average surface pressure on Mars right now. So liquid water should be possible in the valleys and during the middle of the Martian Summer when temperatures like +15° C have been recorded. But don't tell Seaerlas, it'll only encourage him.

Boyboyboy, Me imagining some super-computer getting a nervous breakdown, trying to simulate this stuff!

I think that is the truth.
_

MarsDog · 2005-11-07 05:02:23

http://www.nature.com/news/2005/050221/ … 15_pf.html

"Formisano also announced at the conference that he has found traces of hydrogen fluoride (HF) and hydrogen bromide (HBr) in the atmosphere, which are probably produced when acids break down certain minerals in the soil."

Fluorine in the atmosphere, Must be a lot more in the salty ice underground.

Rxke · 2005-11-07 05:07:05

Just a quick thumbs-up to the people adding to this topic. You guys restored my faith in the New Mars forums!

noosfractal · 2005-11-07 05:38:51

Something I've always wanted to know is how do we manufacture SF6 and C3F8 on mars?
What elements do we need? Sulfate deposits? Flourite?
How do we separate the elements from regolith?
What chemicals are needed and are they used up in the process? If so how do we make these chemicals on mars?

This Feb 2001 Caltech paper ...

http://www.its.caltech.edu/~boxe/boxe1.pdf

says Fluorine is actually a little more common on Mars than on Earth - 30 ppm vs. 20 ppm. On Earth, 4.5 million tons of fluorspar (fluorite ore) is produced annually. It costs about $150/ton. It takes about 2.2 tons of high grade fluorspar to make 1 ton of HF. Apparently the production of HF involves the highly sophisticated "stir ore with water" technique. The Caltech guys would like at least 200 thousand tons of HF per year, but of course, the more the merrier.
_

Rxke · 2005-11-07 05:52:44

...involves the highly sophisticated "stir ore with water" technique....

Now that is a showstopper. Cocktail-stirrers that will work on Mars are devilishly hard to manufacture... So I`ve been told by my Area 51 sources.

'bout the atmospheric fluorine traces... Would it be viable to just "air-mine" these, toghether with the airmining that already will take place for other elements/gasses?

Then crack and re-react them to C3F8 ?

chat · 2005-11-07 07:02:00

noosfractal,

Interesting graph on the snowball earth and its mechanism to escape the freeze.

Since mars is only getting about 1/2 the solar radiation we can expect to need about 2 x the amount of co2 for the same escape mechanism.
Also since mars will only have at best about 1/4 of the atmosphere at its highest point we would need an additional 4x the co2 of the snowball earth.
Adding those two together gives us 8x the snowball earth co2 levels for a mars snowball escape.
With a little math that would give us a rough C3F8 quantity need for Mars to assure an escape, and maybe an additional 10% of that number if the co2 levels on mars are not similar to earths.

The rebound temperatures should be similar to earth after its snowball escape at about 50c to 60c day temperatures, but with less surface water on mars
the co2 and C3F8 will be more persistent in the atmosphere causing the temperature to very slowly decrease.

Viking does give us a little bit of information about the surface chemistry of mars, rust and peroxide seem to be the chief ingredients.
With all the water based experiments Viking did we should have a pretty good idea what heated water and soil does on mars.

As you say we got to go to know.

Rxke,

If mars hovers around the 0c for to long it could create a giant fog ball without much trouble.
Since the cloud formation should be easier on mars with less gravity clouds should readily be formed from it.
That might be a good planetary balance for temperature, or a totally cloud covered mars.
We should probably try and avoid the 0c hovering if possible.

I might be wrong but with less gravity to pull raindrops back down mars should hold an awful lot of h20 in its atmosphere? (mega clouds mega storms)

noosfractal · 2005-11-08 04:14:38

'bout the atmospheric fluorine traces... Would it be viable to just "air-mine" these, toghether with the airmining that already will take place for other elements/gasses?

Formisano puts HF at 40-100 ppb. That's comparable to, say, xenon in the Earth's atmosphere.

Now on Earth, xenon is produced as a sideline to nitrogen production - you liquify air and use fractional distillation to separate out nitrogen, oxygen, krypton and xenon among others. Nitrogen production is quoted in terms of hundreds of thousands of tons per year, oxygen production is quoted in terms of thousands of tons per year, krypton and xenon are quoted in terms of tons per year.

Now cryogenics is fairly easy (low energy) on Mars, so liquifying air isn't going to be a big problem. This works in your favor, but I think your production would be hundreds of tons of HF per year rather than hundreds of thousands of tons. You're only out by a factor of 1000 though. Good tech has leaped bigger gaps. I bet you could get most of that with a properly designed filter/membrane (something like they use in reverse-osmosis desalination - nanotech will help out here) and some of the rest with ridiculous power levels.

However, if HF is in the atmosphere, there are probably some nice fluorspar ores about. It's almost certainly going to be more energy efficient to dig those up first. Atmosphere processing might be a good option for long term maintenance though.

I believe the MRO has instruments that will detect CaF2, so we might get some data on this soon
_

chat · 2005-11-08 05:11:35

karov,

I agree the asteroids are a very attractive way to teraform mars.
A 1km asteroid processed in space could produce mega tons of fluorine carbon h2o etc.
Waste products like o2 hydrogen could help power the production, or send the processed items to the destination.

Mining and processing plants on mars could help, but the energy cost are quite large.

Another option is Titan importation with its methane ammonia lakes and atmosphere.
Should be able to produce some pretty potent greenhouse gasses from it.

karov · 2005-11-08 12:25:41

Something I've always wanted to know is how do we manufacture SF6 and C3F8 on mars?
What elements do we need? Sulfate deposits? Flourite?
How do we separate the elements from regolith?
What chemicals are needed and are they used up in the process? If so how do we make these chemicals on mars?
This Feb 2001 Caltech paper ...
http://www.its.caltech.edu/~boxe/boxe1.pdf
says Fluorine is actually a little more common on Mars than on Earth - 30 ppm vs. 20 ppm. On Earth, 4.5 million tons of fluorspar (fluorite ore) is produced annually. It costs about $150/ton. It takes about 2.2 tons of high grade fluorspar to make 1 ton of HF. Apparently the production of HF involves the highly sophisticated "stir ore with water" technique. The Caltech guys would like at least 200 thousand tons of HF per year, but of course, the more the merrier.
_

200 000 tonnes of HF per annum at on average estimated 25 ppm abundancy???

That means that the Caltech guys will need to excavate, move, process... billions of tonnes of rock in order to have this quantity...

How much will cost these mining&refining works in Joules???

Wouldn`t it be more energy efficient, elegant and at the end - CHEAP, if we produce the flourine in the mother natures way???

http://sait.oat.ts.astro.it/MSAIt750404 … ..712U.pdf

colliding in solar powered particle accelerators in space N, O, Fe, etc, necessary???
Or to use kinda fusor for F-18 production???

http://en.wikipedia.org/wiki/Fusor

noosfractal · 2005-11-08 15:48:42

200 000 tonnes of HF per annum at on average estimated 25 ppm abundancy???

Well Earth has 20 ppm abundancy and we produce enough for 2 million tonnes of HF. Is there any reason you know of that Mars won't have similar high grade fluorite ores?

Wouldn`t it be more energy efficient, elegant and at the end - CHEAP, if we produce the flourine in the mother natures way???

To be honest, I've never thought of nuclear transmutation as particularly energy efficient. But then again, I didn't know that you could build your own fusor for under $10000 8) I'll ask for one for Christmas and see how much fluorine I can make.
_

karov · 2005-11-09 04:22:58

200 000 tonnes of HF per annum at on average estimated 25 ppm abundancy???
Well Earth has 20 ppm abundancy and we produce enough for 2 million tonnes of HF. Is there any reason you know of that Mars won't have similar high grade fluorite ores?
Wouldn`t it be more energy efficient, elegant and at the end - CHEAP, if we produce the flourine in the mother natures way???
To be honest, I've never thought of nuclear transmutation as particularly energy efficient. But then again, I didn't know that you could build your own fusor for under $10000 8) I'll ask for one for Christmas and see how much fluorine I can make.
_

Deffinitelly no reason why Mars to not have as much flourine as Earth. They orginite both in aproximatelly one and a same area of the primordial solar nebula, the fluorine beeing so reactive, remained well bonded and protected from dissipation...

But, flouorine nucleosynthesis is below the iron barrier , hence in principle its production, should be exothermic reaction. Very low efficient , and of course impossible for energy breakeven, but it in principle could be done with comparativelly little net energy influx... In space the solar energy is not matter of quantity, but of REAL ESTATE -- to capture it you should occupy certain area perpendicular/orthogonal to the direction of the insolation. Other cost-maker is the mirrors them selves , but regarding the film flimsy sheets of solar sail material, actually you need only tiny amounts of solid material. Both the resourse and the space are VERY abundant, hence cheap up there. You need only small C-type asteroid to build the solar power capturing devices, and the accelerator or other transmutational device.

Even the energy consumed to dig out and process say 1 km3 per annum of martian rock to be less, which I personally doubt, the matter is WHERE the energy should be delivered and how to be used.

In terms of infrastuctre, one thing is several km2 of dirt cheap Si-photoelectric convertors with 10-15% efficiency coupled with dirt cheap feromagnetic accelerator, zero G+vacuum site of separation, cryocooling-by-just-shading, etc... than to build, exploit and maintain hundreds of thousands of tractors, buldozers, trucks, thousands of factories, etc. ON planet...

We could afford very little production efficiency in space, and still the production to be competitive compared with clasical on-surface excavation+processing.

The other great advantage of flourin-for-mars-from-space ( doesn`t matter whether from mined asteroids or fluorine transmitators ) is that we could produce and provide in the martian atmosphere the whole necessary quantity of C3H8 "in one shot", not to wait gradual production and relase of modest 200 000 tonnes per year.

In the case of asteroid mining and say, estimated presense of 5 ppm of fluorine in the composition of one more primordial nebula stuff ( minus H+He ) asteroid, these 200 000 tonnes an year we can have if distilate "only" 40 bln tonnes of asteroidal / cometary material via brutal solar oven evaporation and hence destilation column or/and centrifuge. This comes along with all other elements ready - carbon, metals.....

-- one about 1.5-2 km wide asteroid processed per year. Still needing tremendous solar power - I don`t have time now to "calculate", i.e. to estimate dozens of billions of metric tonnes rock evaporation versus artificial flourine nucleosynthesis` energy consumption, but my feel is that the second is more economical.

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