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Such as... a human prospecting mission?
Use what is abundant and build to last
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On Earth most of our Platinum based minerals and our gold and of course Rare Earths are the result of asteroidal impacts.
The Moon as a lower gravity well will have had asteroidal impacts that the metal rich asteroids will have likely survived so being able to be dug up insitu. Dennis Wingo is the main proponent of this idea.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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LCROSS is not good evidence? That was direct observation.
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I suppose one could argue that the LCROSS results are not indicative of the rest of the Moon, which is definitely an argument that could be made based on the presence of all of those rare metals, which were largely speaking not found in the samples taken from Apollo. For the concentration of lunar soil, I look to the JSC-1 Lunar Soil Simulant, which should be of very similar composition to the surface of the Moon. According to NASA, JSC-1 is "a glass-rich basaltic ash which approximates the chemical composition, mineralogy, particle size distribution, and engineering properties of lunar mare soil." Next to it, a representative sample of the composition of lunar soil is given. Both are fairly similar. Now, compare this to the ejecta spewed up by LCROSS: Of elements found by LCROSS but not found in the lunar soils returned by Apollo:
3.1% Zinc
2.4% Vanadium
1.6% Gold
1.2% Mercurcy
This totals 8.3% of the material discovered by LCROSS; this is just in elements found in the crater which were not found in the Apollo samples. If the water found there is of meteoric origin, I would expect to find these in the Apollo samples, or at least the ones from craters. To my knowledge no such finds have been made. If it originates from the solar wind, I would also expect to find these metals across the planet, which they are not (further, I would expect to find them in much lower quantities compared to the amount of hydrogen and helium). Now, unless there is something about the poles of the Moon which attract meteorites more than the rest of the planet does, a hypothesis which seems dubious to me, either the LCROSS probe observed something that was not truly found in the soil (contamination from the impactor? Selective ejection of these elements for some reason?), the crater it impacted was very different from what would normally be expected to be found at the lunar poles.
I'm not a scientist, but I don't think I've gone far wrong in any of this. Have any of the planetary geologists looking at the LCROSS data addressed this difference in composition compared to the fairly well known composition of Lunar regolith elsewhere on the Moon?
-Josh
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LCROSS is not good evidence? That was direct observation.
No, LCROSS was not good evidence for gold and mercury. Why not?
1) They were detected by UV spectroscopy in the ejecta plume. To the best of my knowledge this is not a good method to detect these elements, only volatiles.
2) Concentration of gold and mercury in shadowed craters is extremely unlikely -there is not mechanism to do so.
3) The possibility of contamination cannot be ruled out. There was certainly gold on the spacecraft, I don't know if there was mercury.
4) The sole paper mentioning these elements does not discuss them, suggesting that the authors don't trust the results
So we have people building entire imaginary industries on the basis of a single, highly unreliable analysis on possibly contaminated material. If you tried to do that in the real world you might well end up in jail.
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I suppose one could argue that the LCROSS results are not indicative of the rest of the Moon, which is definitely an argument that could be made based on the presence of all of those rare metals, which were largely speaking not found in the samples taken from Apollo. For the concentration of lunar soil, I look to the JSC-1 Lunar Soil Simulant, which should be of very similar composition to the surface of the Moon. According to NASA, JSC-1 is "a glass-rich basaltic ash which approximates the chemical composition, mineralogy, particle size distribution, and engineering properties of lunar mare soil." Next to it, a representative sample of the composition of lunar soil is given. Both are fairly similar. Now, compare this to the ejecta spewed up by LCROSS: Of elements found by LCROSS but not found in the lunar soils returned by Apollo:
3.1% Zinc
2.4% Vanadium
1.6% Gold
1.2% Mercurcy
This totals 8.3% of the material discovered by LCROSS; this is just in elements found in the crater which were not found in the Apollo samples. If the water found there is of meteoric origin, I would expect to find these in the Apollo samples, or at least the ones from craters. To my knowledge no such finds have been made. If it originates from the solar wind, I would also expect to find these metals across the planet, which they are not (further, I would expect to find them in much lower quantities compared to the amount of hydrogen and helium). Now, unless there is something about the poles of the Moon which attract meteorites more than the rest of the planet does, a hypothesis which seems dubious to me, either the LCROSS probe observed something that was not truly found in the soil (contamination from the impactor? Selective ejection of these elements for some reason?), the crater it impacted was very different from what would normally be expected to be found at the lunar poles.
I'm not a scientist, but I don't think I've gone far wrong in any of this. Have any of the planetary geologists looking at the LCROSS data addressed this difference in composition compared to the fairly well known composition of Lunar regolith elsewhere on the Moon?
Josh
I can't stress strongly enough that I would believe the Apollo data over the LCROSS dat when it comes to the heavier elements. The Apollo data is validated by hundreds of analyses using different methods. The LCROSS data is a single analysis that can't be trusted to give meaningful results for heavier elements. UV spectroscopy is great for volatitles, useless for anything else.
Those numbers are rediculous. Several analyses of the target material with similar results by trustworthy methods - XRF, APX, ICPMS - would be a sifferent matter.
You ask if any scientists have looked at this. I am a planetary scientist (admittedly Mars) with more than a decade experie4nce in the exploration industry looking for a range of commodities including gold. There are some largish holes in the ground in Google Earth that are at least in part my responsibility. So when I think these results are almost certaonly spurious, I think I have some basis for that opinion.
I also find the silence of th mission scientists on these results telling. They quoted them, but did not discuss them, the mostly likely explanation for this is, IMHO, because they think they are spurious.
Last edited by JonClarke (2012-01-02 15:38:08)
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So... we're quite certain there's abundant CHON at the Lunar poles? Sounds good to me. The absence of Gold does not mean we can't build a viable Lunar infrastructure, it just means we have to look elsewhere for profit, such as the KREEP.
Use what is abundant and build to last
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So... we're quite certain there's abundant CHON at the Lunar poles? Sounds good to me. The absence of Gold does not mean we can't build a viable Lunar infrastructure, it just means we have to look elsewhere for profit, such as the KREEP.
I think it is certain there are abundant volatiles at the poles. More work is needed on how to do this - the detailed composition, the processing, how to operate in darkness and very low temperatures etc. But probably we can make a station self sufficient.
Exporting volatiles, that is a different story. You need a market, a business model, and a whole slew of new technology. Plus you need to operate everything on a much larger scale. It is possible, but not yet.
How on earth would you make a profit from KREEP?
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Jon-
I'm plenty willing to accept your credentials, I was simply not informed of them. In any case, I'm not surprised that there are reasons to believe that the concentrations of metals, at the least, found in the crater at the pole was not representative of the moon as a whole. I was thinking that it could be a result of some very odd comet hitting the Moon (It is my understanding that the vast majority of comets simply do not have the concentration of elements found in that plume, even if you just consider the non-volatile parts), which would imply that there might not be as much water elsewhere as there was in this crater.
I emphatically agree that the elemental compositions found in the Apollo samples are by far the most reliable way to determine the composition of the lunar regolith at present. Even if the number of widely separated sampling locations are small, there seems to be a pretty wide variety of types of places sampled and, most importantly, the stuff was brought back to Earth and cut up and analyzed a billion different ways.
Even if the metals are not as they were found to be by LCROSS, I would think that the water found would be, correct? So we're probably looking at ~5.5% water in combination with the usual suspects in terms of metal and semi-metal oxides.
For those not familiar with the term (I had to look it up), KREEP stands for Potassium and other alkalis (Atomic symbol for Potassium is K) Rare Earth Elements, and Phosphorus. I would assume that the Chandrayaan-1 results, which did after all find very significant amounts of water, are still valid?
-Josh
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2) Concentration of gold and mercury in shadowed craters is extremely unlikely -there is not mechanism to do so.
Mercury can easily sublimate into a gas. Therefore it amenable to accumulation in the cold traps.
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JonClarke wrote:2) Concentration of gold and mercury in shadowed craters is extremely unlikely -there is not mechanism to do so.
Mercury can easily sublimate into a gas. Therefore it amenable to accumulation in the cold traps.
Only in the metallic form. Not when it is locked up in silicates. And lunar rocks have very low Hg - less than 0.3 parts per billion. That is less than 1% of the average abunance in terrestrial cust.
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In the absence of a hydraulic cycle it is entirely possible that metallic ores from asteroidal impacts stay resident at their impact site indefinitely. If Cabeus or a neighboring crater were the result of an impact from a metal-rich asteroid, the LCROSS results would make perfect sense.
Apollo is not a very trustworthy guide to the geology of the moon with respect to mineral prospecting. The "deep" drills used in the later missions were only to a depth of 3m--and almost entirely composed of regolith/impact ejecta. That could not be more different than the geology of permanently shadowed crater floors in the poles.
As to the accuracy of the LCROSS results, I know many of core team personally through my work and have attended almost all of their science briefings. They are very dedicated scientists, and with support from the entire Ames center have done a thorough job in isolating possible contamination and accounting for instrument anomalies (including multiple practical tests at the vertical gun range, so it's not just theoretical either). I would trust their data.
That's not to say that one can extrapolate LCROSS results to the rest of the Moon, or even just the rest of Cabeus. But the results are definitely real, and part of the larger story.
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In the absence of a hydraulic cycle it is entirely possible that metallic ores from asteroidal impacts stay resident at their impact site indefinitely. If Cabeus or a neighboring crater were the result of an impact from a metal-rich asteroid, the LCROSS results would make perfect sense.
Apollo is not a very trustworthy guide to the geology of the moon with respect to mineral prospecting. The "deep" drills used in the later missions were only to a depth of 3m--and almost entirely composed of regolith/impact ejecta. That could not be more different than the geology of permanently shadowed crater floors in the poles.
As to the accuracy of the LCROSS results, I know many of core team personally through my work and have attended almost all of their science briefings. They are very dedicated scientists, and with support from the entire Ames center have done a thorough job in isolating possible contamination and accounting for instrument anomalies (including multiple practical tests at the vertical gun range, so it's not just theoretical either). I would trust their data.
That's not to say that one can extrapolate LCROSS results to the rest of the Moon, or even just the rest of Cabeus. But the results are definitely real, and part of the larger story.
Even a metallic asteroid is so dispersed during the impact process that ores do not result, not even of the most adundant elements.
I know only one of the LCROSS team well, but I too have the highest regard for them. But this does not mean that UV spectroscopy gives meaningful results for heavy element abundances. Please present some hard evidence to the contrary.
I am sorry, but in what way are the Apollo samples not trustworthy as a guide to mineral prspecting? Apart from the obvious with respect to volatites.? What evidence do you have that the polar rocks are funadmentally different from those we have seen already? What is the relevence for the drill depth?
Last edited by JonClarke (2012-01-02 23:24:10)
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I don't believe there is significant gold or mercury in lunar craters. Not without good evidence.
...I can't stress strongly enough that I would believe the Apollo data over the LCROSS dat when it comes to the heavier elements. The Apollo data is validated by hundreds of analyses using different methods. The LCROSS data is a single analysis that can't be trusted to give meaningful results for heavier elements. UV spectroscopy is great for volatitles, useless for anything else.
Those numbers are rediculous. Several analyses of the target material with similar results by trustworthy methods - XRF, APX, ICPMS - would be a sifferent matter...
First of all Apollo never went to permenently shadowed regens so how could they have data about them? And the data it did bring back seems to corroborate LCROSS. Coreing samples where taken up to three meters deep, the upper most portions of those samples had depleted levels of gold but the lower samples did not. There is a theory that the gold particles electrostatically repel themselves much farther than other elements after being struck by micro meteors and that they would accumulate in cold traps. Mercury should accumulate for obvious reasons just like water.
Certainly there needs to be more exploration before you start sending mining equipment, but just ignoring the evidence we do have is rather irresponsible. I know there are allot of mars fans out there who wish everyone would pretend like the moon doesn't exist and deem it as a distraction. I am just the opposite I think the moon is necessary for the future of life. We can do allot of science on mars by going direct but if you want to get serous about colonization things can happen much more quickly if we have a large profitable enterprise that can fund the development of space infrastructure and get the launch rate up.
I think platinum groups are a good possibility, the moon is a big place and its been there for a long time; bound to have been some low speed impacts of platinum bearing asteroids every once in a while. But that sort of mining is relatively small scale compared to what an abundant supply of gold could sustain.
There is a whole ecological angle too. Mining on earth damages the environment, on the moon there are no endangered species to protect. Imagine a future where gold is autonomously mined and kinetically shot back to earth. So abundant that your grandchildren will wire there homes with it and find it amusing that it was once so valuable.
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JonClarke wrote:I don't believe there is significant gold or mercury in lunar craters. Not without good evidence.
JonClarke wrote:...I can't stress strongly enough that I would believe the Apollo data over the LCROSS dat when it comes to the heavier elements. The Apollo data is validated by hundreds of analyses using different methods. The LCROSS data is a single analysis that can't be trusted to give meaningful results for heavier elements. UV spectroscopy is great for volatitles, useless for anything else.
Those numbers are rediculous. Several analyses of the target material with similar results by trustworthy methods - XRF, APX, ICPMS - would be a sifferent matter...First of all Apollo never went to permenently shadowed regens so how could they have data about them? And the data it did bring back seems to corroborate LCROSS. Coreing samples where taken up to three meters deep, the upper most portions of those samples had depleted levels of gold but the lower samples did not. There is a theory that the gold particles electrostatically repel themselves much farther than other elements after being struck by micro meteors and that they would accumulate in cold traps. Mercury should accumulate for obvious reasons just like water.
The apollo sample suite is sufficiently diverse to allow calculation of global and crustal abudnances. It is back up by the Luna samples and the lunar meteorites. The Moon is very strongly depleted in Hg, and other volatile metals. That does not preclude local concentrations but does make them unlikely. That's the first point.
Secondly, as I said before, UV spectoscopy is not a reliable tool for measuring heavy elements. To draw far reaching conclusions, as is happening here, based on one quite possibly spurious reading from an unreliable instrument, completely unwarranted.
What's the evidence for gold distribution in the lunar regolith? Whosde theory is it about electrostatic mobiliation? Is it published? Is their any experimental evidence? Becausde it seems extremely unlikely. Gold is not common in lunar rocks either, and does not occur as descrete grains but dispersed in other minerals.
As I have already said, Hg would only be concentrated "like water" if it could be volatilised out of the rocks. This requires it to exist as a separate metallic phase (or possibly sulphide). There is not enough Hg in the rocks for this, it is locked up in the silicates. It just isn' going to happen.
Certainly there needs to be more exploration before you start sending mining equipment, but just ignoring the evidence we do have is rather irresponsible. I know there are allot of mars fans out there who wish everyone would pretend like the moon doesn't exist and deem it as a distraction. I am just the opposite I think the moon is necessary for the future of life. We can do allot of science on mars by going direct but if you want to get serous about colonization things can happen much more quickly if we have a large profitable enterprise that can fund the development of space infrastructure and get the launch rate up.
Crap data is not evidence, it is just... crap. No degree of wishful thinking maks it otherwise.
The comment about Mars is a completely irrelevant to the case. This isn't one of the pointless Moon vs Mars argumen ts. This is a matter of evaluating the evidence and understanding the technology.
I think platinum groups are a good possibility, the moon is a big place and its been there for a long time; bound to have been some low speed impacts of platinum bearing asteroids every once in a while. But that sort of mining is relatively small scale compared to what an abundant supply of gold could sustain.
There is no evidence that impacts produce PGE concentrations. The mixing ratios of impactor and target materials is just too high.
There is a whole ecological angle too. Mining on earth damages the environment, on the moon there are no endangered species to protect. Imagine a future where gold is autonomously mined and kinetically shot back to earth. So abundant that your grandchildren will wire there homes with it and find it amusing that it was once so valuable.
Since there is no reliable evidence that there is abundant gold on the Moon this is just wishful thinking. And what makes you think it could be mned more cheap on the Moon than on than on Earth?
BTW properly done, terrestrial mining has minimal evironmental impact.
Such arguments don't advance the case for lunar development. Rather the opposite.
Last edited by JonClarke (2012-01-03 04:16:35)
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Such as... a human prospecting mission?
I can't imagine the level of investigations required to prove up reserves not being done with human presence. I could be wrong - I understan people are proving up deep sea sulphide deposits with ROVs and other remotely controlled insturments, although I think there is some use of crewed submersibles too.
Last edited by JonClarke (2012-01-03 04:22:31)
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Only in the metallic form. Not when it is locked up in silicates.
Mercury locked up in silicates? Cite? So as I know it occurs as a native metal or as HgS.
And lunar rocks have very low Hg - less than 0.3 parts per billion. That is less than 1% of the average abunance in terrestrial cust.
You heat cinnabar and the mercury vapor separates out. Given that the lower lunar latitudes get quite hot and it's vacuum, you'd expect the Mercury vapor to be baked out of the lunar crust.
You'd expect mercury to be scarce in the lunar crust, for the same reason you'd expect scarcity of other volatiles.
And those volatile vapors that don't escape to outer space move about the moon's surface. If their travels take them to a cold trap, there they will stay.
Your assertion that there's no mechanism to concentrate mercury in the cold traps is wrong.
Is the same true of gold? I don't know. Off hand, I can't imagine a mechanism that would concentrate gold at the lunar poles. But just because I can't think of one, doesn't mean such a mechanism can't exist. We don't know the history of the minerals in the cold traps. While I'd agree the gold finding isn't conclusive, I reject the notion that it should be disregarded just because it doesn't meet our expectations.
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Even a metallic asteroid is so dispersed during the impact process that ores do not result, not even of the most adundant elements.
Cite?
Lunar meteorite impacts can be as slow as 2.4 km/s.
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Jon, I respect your credentials but you're clearly talking outside of your expertise.
Recent analysis of Apollo data and later orbiters show large-scale migration of dust particles due to electrostatic transport. There are too many sources to site one individually--just google "lunar dust migration".
Large metallic and stony impactors are known to survive impact on Earth, clearly the same thing is going on on the Moon where impacts can be much, much slower. Note that the whole raised lunar farside is now believed to be composed of impactor material from Earth's "second moon" that impacted at reduced velocity.
Apollo data is only representative of what it measured--thoroughly mixed impact ejecta regolith, dozens of larger ejecta fragments, and a handful of crustal samples with very little, if any geologic context. This is both a) a small part of the lunar geology story, and b) not relevant to the current discussion about cold traps and impact-deposited ores, both of which we now know are processes the Apollo results shed no light on.
For cold traps, look at all the papers that have come out about lunar dust migration and Carle Pieters' lunar hydrologic cycle. For impactor-ore deposits, you need not look any further than Sudbury Basin in Canada, now one of the world's largest supplies of nickel and copper ores. The processes which formed Sudbury Basin certainly occurred on the Moon (and Mars) as well, resulting in large concentrated deposits in the crater rim and floor of impact basins with the right characteristics.
Mining the Moon is not so crazy when you consider that these relatively pure ores are unaffected by an active geology or hydrologic cycle and weathering, and may lie just a few meters under the surface (this would explain what LCROSS observed). Within cold traps it is likely that small impactors (LCROSS sized) have already excavated quite a bit of ore that would just be sitting there on the surface in bite-sized chunks.
Is the difficulty of developing cheap, reliable cislunar transportation really that much harder than digging tunnels 2-3km in the ground as we currently do to get such resources on Earth?
Last edited by Mark Friedenbach (2012-01-03 12:52:48)
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Jon, I respect your credentials but you're clearly talking outside of your expertise.
Recent analysis of Apollo data and later orbiters show large-scale migration of dust particles due to electrostatic transport. There are too many sources to site one individually--just google "lunar dust migration".
Large metallic and stony impactors are known to survive impact on Earth, clearly the same thing is going on on the Moon where impacts can be much, much slower. Note that the whole raised lunar farside is now believed to be composed of impactor material from Earth's "second moon" that impacted at reduced velocity.
Apollo data is only representative of what it measured--thoroughly mixed impact ejecta regolith, dozens of larger ejecta fragments, and a handful of crustal samples with very little, if any geologic context. This is both a) a small part of the lunar geology story, and b) not relevant to the current discussion about cold traps and impact-deposited ores, both of which we now know are processes the Apollo results shed no light on.
For cold traps, look at all the papers that have come out about lunar dust migration and Carle Pieters' lunar hydrologic cycle. For impactor-ore deposits, you need not look any further than Sudbury Basin in Canada, now one of the world's largest supplies of nickel and copper ores. The processes which formed Sudbury Basin certainly occurred on the Moon (and Mars) as well, resulting in large concentrated deposits in the crater rim and floor of impact basins with the right characteristics.
Mining the Moon is not so crazy when you consider that these relatively pure ores are unaffected by an active geology or hydrologic cycle and weathering, and may lie just a few meters under the surface (this would explain what LCROSS observed). Within cold traps it is likely that small impactors (LCROSS sized) have already excavated quite a bit of ore that would just be sitting there on the surface in bite-sized chunks.
Is the difficulty of developing cheap, reliable cislunar transportation really that much harder than digging tunnels 2-3km in the ground as we currently do to get such resources on Earth?
Also, there are no land costs, no environmental legislation, no mining rights costs, no taxation...that gives lunar mining a really flying start.
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Jon, I respect your credentials but you're clearly talking outside of your expertise.
The old "I respect your credentials but..." approach. We will see. Until then, kindly don't make assumptions about what I do or do not know.
Recent analysis of Apollo data and later orbiters show large-scale migration of dust particles due to electrostatic transport. There are too many sources to site one individually--just google "lunar dust migration".
I learned this about 30 years ago It is not that recent an idea. While almost certainly correct, it does not mean in can be invoked to explain gold ocurrences. Gold occurs at ppb level in lunar rocks and therefore will be locked p in silicate grains. It won't show differentil movement under electrostatic influence.
Large metallic and stony impactors are known to survive impact on Earth, clearly the same thing is going on on the Moon where impacts can be much, much slower. Note that the whole raised lunar farside is now believed to be composed of impactor material from Earth's "second moon" that impacted at reduced velocity.
Small impactors survive on Earth, forming meteorites. This is because they are slowed by the atmosphere. Large ones are not and are vapourised or dispersed as droplets, mixed with a much greater volume of ejected target rocks. They Moon has no atmosphere and even the smallest bodies will impact at>2.8km a second, and almost always considerably more. That is why no meteorites were found on the Moon, only geochemical signatures and tiny nickel-iron sperules.
The as yet unproven hypothesis for the formation of the lunar farside is a very special case, not relevant for normal impacts.
Apollo data is only representative of what it measured--thoroughly mixed impact ejecta regolith, dozens of larger ejecta fragments, and a handful of crustal samples with very little, if any geologic context. This is both a) a small part of the lunar geology story, and b) not relevant to the current discussion about cold traps and impact-deposited ores, both of which we now know are processes the Apollo results shed no light on.
Please read the Apollo papers more carefully. The impact regolith is mixed, but not uniform, it maries from place to place with the dominant signature being the underlying substrate. Geological contacts were diffused, but still recognisable. Every site had its unique site of rocks.
With respect to point a), yes, some of the features of the Apollo samples were indeed local. But it is possible from a suite of ignous rocks to determine global compositions using geochemical patterns, espcially the rare earths. It is from this that the global magma ocean was deduced. So we do know globally that the Moon is etremely depleted in some elements, especially volatile metals like mercury. We also know that at the levels it occurs in Hg is not forming separate phases, so can't be sweated out by the diurn al cycle to move to cold traps.
b) The Apollo samples are entirely relevant to the possibility of impact formed ore bodies. We know from multispectal, X ray and gamma ray data from multiple systems that the polar crust is not that different to that sampled by Luna and Apollo, or in the lunar meteorites (with the exception of of course of the deeper parts of the SPA Basin, which is out of the area of discussion). They are also relevant in that they contain very little water, suggesting that the polar water comes from external sources, such as comets.
Further, the whole point I am trying to make is that the Apollo data is reliable - multiple assays by multiple proven, calibrated techniques. The UV spectoscopy data on Hg, Au, and the rest is one measurement by an ureliable technique, giving results that don't make sense at all.
But that does not seem to be stopping people here creating entire economies out of one crappy result. That isn't even wrong.
For cold traps, look at all the papers that have come out about lunar dust migration and Carle Pieters' lunar hydrologic cycle.
Read them when the first came out (actually got given copies while theywere still embargoed). Nice work. But complete irrelevant to the existence of Au and Hg at the lunar poles, wafting about in the lunar breeze.
For impactor-ore deposits, you need not look any further than Sudbury Basin in Canada, now one of the world's largest supplies of nickel and copper ores. The processes which formed Sudbury Basin certainly occurred on the Moon (and Mars) as well, resulting in large concentrated deposits in the crater rim and floor of impact basins with the right characteristics.
Sigh, this takes me back. It is about the first question anybody asks when they first here that Sudbury is an impact feature. I asked it myself as an undergraduate. And it is quite wrong. There is too much nickel and way too much copper for them to be derived from an impactor. Plus their distribution is quite wrong within the astrobleme itself. The impact was important in generating the high temperature melts that host the mineralisation, but the Ni and Cu are terrestrial. And you don't need an impact to generate large Cu-Ni sulphide deposits - large scale basaltic (Norilsk) or ultramafic volcanism entirely endogenous in origin will suffice.
Mining the Moon is not so crazy when you consider that these relatively pure ores are unaffected by an active geology or hydrologic cycle and weathering, and may lie just a few meters under the surface (this would explain what LCROSS observed). Within cold traps it is likely that small impactors (LCROSS sized) have already excavated quite a bit of ore that would just be sitting there on the surface in bite-sized chunks.
Active geology and weathering are processes that create and improve ore deposits, not the opposite.
Is the difficulty of developing cheap, reliable cislunar transportation really that much harder than digging tunnels 2-3km in the ground as we currently do to get such resources on Earth?
Yes it is. For the cost of a single large lunar orbiter like LRO you can find, prove up and bring to production a world class orebody in just about any commodity you like. It does not matter if Musk is a miracle worker and can reduce costs to a 10th of what they are at present, it will take a lot more than an orbiter to prove up an orebody. Hundreds of drill holes, ground geophysics, thousands of assays, months of test work, getechnical surveys. It will always be easier to do this on Earth.
Lunar mining will be for lunar needs, not terrestrial.
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Also, there are no land costs, no environmental legislation, no mining rights costs, no taxation...that gives lunar mining a really flying start.
In other words, an operating nightmare. Without good goverance companies will not invest, the risk to too great. The is need such that it will emerge when it is required. It is not the lawless regions of the world that attract the greates exploration investment, but the well regulatd ones. For every company prepared to risk the DR of Congo or Liberia there are a hundred investing in Australia or Canada.
No environmetal legislation? There are already agreements involving space debris and the EM bands. There will be environmental regulation on the moon too, making sure that the emissions from the fluorine alumina extration plant don't contaminate the volatile processing at the south pole. That the dust raised by the robots processing the regolith for titania doesn't intefer with the 100 metre UV telescope in Plato. Or the radio communications from consetllations of satellites upset the radio quiet zone surounding the 10 km farside radio dish. Even to preserve the aesthetics of the Moon from Earth (e.g. "no structure on the near side of the Moon may be larger than 10 km").
No land or mining right costs? Who pays for the admistration and policing of liscences and the system of arbitration of dispute? No tax? really? While the head offices are on Earth or the products are sold there you can be sure there will be taxes, royalities, tariffs, and the rest.
If we are going to talk about mining let's look at how the mining industry really operates.
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JonClarke wrote:Even a metallic asteroid is so dispersed during the impact process that ores do not result, not even of the most adundant elements.
Cite?
Lunar meteorite impacts can be as slow as 2.4 km/s.
Some perhaps, but very few.
This paper http://arxiv.org/abs/0907.3010 calls imapctors below 11 km/s "slow", Figure 3a shows that there are effectively none below 10 km/s, the text also says that the average lunar impact is 22.4 km/s (almost the same as Earth's 23.1 km/s), Figure 3a shows some impact velocities as high at 50 km/s.
The text of this paper has slightly different numbers - average of 17 km/s and a lower limit of 12 km/s www.sciencemag.org/content/309/5742/1847.full.pdf .
Yet another paper http://128.97.36.172/Warren%20et%20al-s … aradox.pdf suggests 16 km/s as the average and suggests that this number has not changed much throughout the history of the Moon.
I could list some more, but instead I am going to bed. Good night!
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Hop wrote:JonClarke wrote:Even a metallic asteroid is so dispersed during the impact process that ores do not result, not even of the most adundant elements.
Cite?
Lunar meteorite impacts can be as slow as 2.4 km/s.
Some perhaps, but very few.
This paper http://arxiv.org/abs/0907.3010 calls imapctors below 11 km/s "slow", Figure 3a shows that there are effectively none below 10 km/s,
No, figure 3a on page 7 does not show there are effectively no lunar impacts below 10 km/s. A significant portion of the the lunar bell curve lies to the left of 10 km/s. What you say is true of the dotted line (earth's impactors).
Furthermore, on page 12 the authors note their models don't match the lunar impact record. "One possible explanation is related to the impact velocity distributions. The leading/trailing asymmetry becomes more prominent when the average relative velocity between the Moon and the projectiles is low. The NEA-like particles are, by their dynamical definition, the “slowest” (relative to Earth) among all the known small body populations in the solar system. That even these slow particles may not fully account for the observed asymmetric distribution in the lunar crater record suggests that there may exist a presently-unobserved population of small objects near the Earth’s orbit that have even lower average relative velocity than the currently known near-Earth asteroids do."
The text of this paper has slightly different numbers - average of 17 km/s and a lower limit of 12 km/s www.sciencemag.org/content/309/5742/1847.full.pdf .
Behind a pay wall. I'll note a 17 km/s average doesn't mean there aren't slower impacts. I am skeptical of the 12 km/s lower limit. I suspect you're misinterpreting this paper as you did the paper by Ito and Malhotra.
Yet another paper http://128.97.36.172/Warren%20et%20al-s … aradox.pdf suggests 16 km/s as the average and suggests that this number has not changed much throughout the history of the Moon.
Again, an 16 km/s average doesn't demonstrate the nonexistence of slower impacts.
Hop's [url=http://www.amazon.com/Conic-Sections-Celestial-Mechanics-Coloring/dp/1936037106]Orbital Mechanics Coloring Book[/url] - For kids from kindergarten to college.
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But complete irrelevant to the existence of Au and Hg at the lunar poles, wafting about in the lunar breeze.
Still waiting for a cite about your mercury silicates.
Native mercury and HgS are much more common.
Baking HgS will cause the mercury vapor to separate out. So you would expect the lunar crust to mercury poor, just as it's poor in other volatiles.
Likewise, you would expect what surface mercury there is to accumulate in the cold traps, just as with the other volatiles.
Last edited by Hop (2012-01-04 10:38:37)
Hop's [url=http://www.amazon.com/Conic-Sections-Celestial-Mechanics-Coloring/dp/1936037106]Orbital Mechanics Coloring Book[/url] - For kids from kindergarten to college.
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