Summery Study and colony location
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Sander Vesik san...@haldjas.folklore.ee
Ok, I have been meaning to go back and lok it up, so here it is - the why do stuff in orbit and not on moon, extracted from teh summer study.
1) colony location: But where should the habitat be placed in the vicinity of the Moon? At first glance the Moon's surface seems a good choice, but any part of that surface receives thes full force of the Sun's radiation only a small fraction of the time. Moreover, on the Moon there is no choice of gravity; it is one-sixth that of Earth and can only be increased with difficulty and never reduced. Space offers both full sunshine and zero gravity or any other value of simulated gravity one might choose to generate. An additional difficulty with a lunar location is related to the major product of the colonies, SSPS's. Transporting them from the Moon to geosynchronous orbit is not economically viable.
For ease of exploitation of the properties of space, the habitat should be located in free space.
2) where to process A variety of alternatives exist for the processing of lunar ores to yield materials for the colony. These involve various combinations of processing site, materials to be produced, and chemistry. Optimization requires a detailed analysis of manifold possibilities. The study limited itself to choosing a plan which seems achievable and advantageous based on reasonable extrapolations of current technology.
The decision as to whether to process at the colony or on the Moon is dictated by various factors. The lunar site has the advantage of being close to the ore source and having a gravity which might be used in some chemical processing.
Lunar processing might be expected to decrease the amount of material to be shipped to the colony. However, closer examination reveals that the colony's shielding requirements exceed the slag production of the processing plant; hence, no transportation is saved by processing at a lunar site.
Moreover, lunar processing also possesses certain definite disadvantages when compared to processing at the site of the colony. Plant facilities shipped from the Earth to the Moon require much greater transportation expense than for shipment to the colony site. In addition, solar furnaces and power plants are limited to a 50 percent duty cycle on the Moon. Without power storage this would curtail operations at a lunar processing site. Radiators for process cooling are less efficient and, therefore, larger when placed on the Moon, because they have a view of the Sun or of the hot lunar surface. Finally, even at only 1/6 of Earth's gravity, components of the plant have significant weight. On the Moon this requires support structure and cranes and hoists during ***embly. But these are not needed if processing is done at the colony site. Based on these considerations, it appears that major processing should take place at the colony site.
So not only did they *NEVER* actually do any actual calculations about what is feasible where and and not just simply resorted to hand waving, they didn't even bother to give much though to handwaving at stuff that did not meet their initial ***umptions - or really, teh pre-ordained goal. Worse, as they mention a lunar base (except smaller) later on anyways, all of teh reasoning for teh rest completely loses its point.
They simply start from here: Fortunately, the design study could draw on substantial earlier work. Active interest in space colonization as a practical possibility began in 1969 when Gerard O'Neill and students at Princeton University undertook a detailed ***essment of space colonization. They aimed at a model to show the feasibility of a space colony rather than an optimum configuration and they selected as a test case a rotating habitat in satellite orbit around the Earth at the distance of the Moon, using solar energy to sustain a closed ecological system. They proposed a habitat constructed of processed lunar ore delivered by an electromagnetic accelerator and located at either the Lagrangian point L4 or L5 in order to make delivery of the ore as simple as possible. (The Lagrangian points are described in ch. 2.) The habitat was configured as a l-km long cylinder with hemispherical end-caps. It was to have an Earth-like internal environment on the inner surface and be supplied with sunlight reflected from mirrors (ref. 1).
and then circularily "prove" that such is indeed a good idea and you should not bother even thinking about anything else. Which in turn of course makes all use of numbers unencessary. Including say finding out if that bloody big colony that was developed for building SPS-s will take less energy than the SPS-s will ever produce and if not, how much it adds to the energy bayback time. But of course, teh builders of NASA socialist space colony republic need not be concerned by such minor details.
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Sander +++ Out of cheese error +++
Rand Simberg newsgro...@transterrestrial.com
Maybe because it was a summer study with volunteers, and limited resources?
Sander Vesik san...@haldjas.folklore.ee
In which case they should have icked an appropriate scope for it.
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Sander +++ Out of cheese error +++
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
I don't see this as a fair statement. The only way they could have delved as deeply into numerical comparisons as you might demand was if they had done 2 studies of equal magnitude: one for industiralization of space, and another for industiralization of the moon. Maybe they didn't have the time or money to do 2x the work.
Instead they simply made the following points of logic: 1) HEO can sustain solar-powered operations without expensive storage systems 24/7 99% of the time. The lunar surface can only do this 2 weeks out of every 4.
2) The moon's gravity offers no particular advantage as long as a portion of an orbital facility can rotate. The moon's partial gravity, full gravity, or no gravity at all can be had in HEO depending on what's most advantageous for a given application.
3) HEO represents a reasonable middle ground between being close to the mining site, and being close to the final location for finished products.
4) Lunar surface processing might make sense only if it reduced the amount of material needing to be sent up. Given the ***umption of slag-derived radiation sheilds, they concluded every atom of lunar material sent up was needed. You try to nullify this point simply by saying that you have no interest in radiation shielding, and elsewhere seem to be saying you don't think people will have much to do with ET industrialization.
5) Costs for transporting ore processors and fabrication facilities from Earth to HEO are less than for Earth to lunar surface. I would add that maintenance costs would scale similarly.
6) Heat radiation in vacuum is easier in 0-G away from the lunar surface.
and having made these 6 logical points, proceeded with an ***umption they felt was well-supported by those points.
Untrue. By necessity, we must put mining equipment, and a means of delivering material off the surface, on the moon. That doesn't mean we need to put ore refineries or manufacturing facilities on the lunar surface.
Their recomendation was to hold off on that end of it until there was a requirement for finished products whose end use was on the lunar surface (like M*** Driver 2). Nobody ever said the advantage of HEO processing is that you can blow off doing a moonbase. But being able to get started with a smaller, less-expensive moonbase is a definite advantage.
It seems to me you quoted back several paragraphs were they did indeed think about something else, and listed several disadvantages of that alternate approach. Rather than attempting to disprove the logic, you just complain about it for no reason I can see other than that the scenario they derived differs from the one in your head.
It's not circular logic to accept a set of arguments, and then to proceed based on them. It's up to you to explain how a differing strategy confers an even greater advantage.
Past a point, even O'Neill himself freely conceded that manufacture of SPS from space resources would preceed, not follow, manufacture of large, comfortable habitats. Indeed, he didn't expect the latter until the former was well into the black.
But a point is that once you've set up everything you need to make SPS from ET resources, you pretty much have everything in place needed to make habitats from ET resources.
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
I think you would only have a valid argument if the study did not mention a single word about the option of processing on the lunar surface. That might have pointed to the possibility of them having overlooked an option.
Instead, in the paragraphs you quoted they brought up the issue, outlined a number of logical arguments weighing against the idea, and then went on. If you think they erred, then you need to demonstrate why their logical points were incorrect, or point out an aspect of alternate strategies they overlooked which would dominate over the points they raised.
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
Sander Vesik san...@haldjas.folklore.ee
Not relevant as we have no special processes to take advantage to any of these for the issues at hand like extracting aluminum or oxygen. And no apparent sources of funding for such.
No. This can *NOT* simply be claimed - it has to be proven by at least some calculations showing that that really is the case.
No. Again. one cannot ***ume there will be humans unless you can show that you *CAN* have gumans there and still remain profitable. Or compete with others who also make SPS-s, except go about it differently and with a much smaller human crew.
the same also applies to selection of orbit for the SPS building factory.
Only relevant if it is not completely swamped by the need to launch more from Moon and transport it all to HEO.
Except for the last, these are all completely unwarrantied. There simply is no reason to make such ***umption.
Again, they have no numbers to show that any of this makes any sense whatsoever.
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Sander +++ Out of cheese error +++
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
If you simply reject the notion that a more-continuously-available source of energy is advantageous to energy-hungry operations like ore refining and metal-working, then there's nothing that I or anyone else could say that you would choose to consider a valid argument. They say, "Continuous availability of energy is an advantage." You say, "No, it's not," and consider that you've won the argument. That's fine for you, but don't complain when you see so many fellow space advocates continuing to spend time discussing the only NASA-funded studies ever made of space industrialization. They may not choose to utterly dismiss the same operational advantages that you do.
It would effect flow of material as long as the m*** driver could keep up with material flow-through at the refining/fabrication end. I ***ume that they had calculated it would. I base that ***umption on the fact that early in this research, the moonbase had a small nuclear reactor buried in a pit.
At a later point, the reactor was gone, and the m***-driver was powered solely during the lunar day by solar panels. I'm pretty sure this was due to a calculation that even a m***-driver operating on a 50% duty cycle 4 weeks long could still keep up. Evidently they had concluded that making the m***-driver operate continuous was not even worth the political h***le of getting a nuke to the moon.
Besides, there has to be some down-time anyway for repairs and maintenance on the m***-driver, and switchover of m***-catchers at the L-2 point.
Nobody ever argued one /can't/ have continuous power on the moon, only that the uninterrupted availability of solar power in HEO is advantageous. That advantage includes not having to pay for a separate beaming power plant elsewhere, or a separate nuke.
Not sure if I'm correctly parsing this part. The only point is that one cannot cite the gravity of the moon as some advantage for processing there over orbit. The point is itself a denial of the relevance of an often-argued advantage of basing industrial operations on the moon.
This is based on delta-V's. Do you think the Summer Study did no calculations on delta-V's?
In my opinion, the burden of proof is on you to prove that space can be economically developed without humans being involved, or with hardly any.
The recent experience with the DARPA competition doesn't give one much cause for optimism here. If we can't even so much as design an automated ore car that would drive itself from the site of mining to the site of refinement, what other gaps exist throughout the enterprise?
True. It's just an area where you and the Summer Study group proceed from different ***umptions. They ***umed the same amount of material would be launched in either case.
You've yet to sell me on that.
I'd consider it a truism that manufacturing on the lunar surface makes more sense for products intended for lunar surface use than those intended for use elsewhere.
Look, this is what it boils down to: You argue in favor of lunar surface industry mostly because you're convinced that it reduces the lunar launch requirement from the m*** of the ore needed to the m*** of the finished products. The Summer Study recommended the High Frontier plan based on the fact that m***-driver launch of raw materials from the moon should be much less expensive than launch of finished products due to G-force limitations and bore size issues, plus the half-dozen or so points that you quoted back.
You simply pick and chose your ***umptions and care-abouts seemingly based on whatever brings you to the conclusion of lunar-surface industry. That's fine for you, but quit wondering why so many other space advocates are paying attention to the published and peer-reviewed studies because not everyone is going to pick and choose their care-abouts in order to arrive at the same conclusions you do. Some of us are proceeding from the ***umption that people are going to be involved in this process and will require shielding. Some of us see operational advantages in one power plant in orbit versus two on some surface. Feel free to consider us idiots for doing so, but don't act like it's all a foregone conclusion and that our ***umptions are obviously wrong to anybody.
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
RobertM ...@YahooGroups.Com
It would have been nice if the competition had been successful, but it is overkill for what we need on Luna. It isn't necessary for an ore car to drive many miles under totally robotic control with no human intervention. All that is necessary is for the ore car to drive a few feet at a time, just like the rovers on Mars are doing now, except with a tele-operation cycle tuned for 2.5-second delay instead of half-hour or hour delay, that is a GUI where the operator just points and motions what to do, waits a moment, sees how it worked, and then repeats for the next operation or for a corrective operation. As travel routes are better known, both by practice and by navigation beacons getting installed along the way, drive segments can be made longer and longer, but long drive segments aren't necessary to get started doing mining work on Luna.
Those are two extremes. What about processing Lunar materials into specific compositions such as particular metals etc., using some of those materials to fabricate actual working parts on Luna to bootstrap industry there, but *not* launch those fragile parts to space, and launching the rest of the processed materials as ingots of whatever size is a best match for the m*** launcher? Why do you ***ume only one extreme, raw ore, and the other extreme, fragile finished products, are the only possible things to launch from Luna? Why not launch ingots of processed ore? The specific parts needed on Luna, and needed in space, are likely to be different, so it's not duplication to build fabrication infrastructure in both places. But the processing of the raw ore to produce ingots of specific chemical composition would be mostly the same regardless of final destination, so why not do most of that on Luna and avoid duplicating that in space?
Note: I'm ***uming no humans on Luna, only tele-operated/robotic equipment, at least during the first ten or so years of bootstrapping the Lunar industry. But in HEO, there might be some humans from time to time, because it's relatively easier to get humans there and back safely and cheaply.
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
Yes, but working materials for what purpose? To build a moonbase? Or to build a SPS in Earth orbit? If the former then fine, but that's a different scenario than the one being debated here. If the latter, we either have to built a system for lifting ore up from the moon, or a system for lifting up components (or ingots as you would have it) from the moon. We can't begin working projects in cislunar space until one or the other is built anyway.
You're making valid points here. But I only brought it up to raise the point that where our abilities to do things with automation are concerned, our expectations frequently exceed our actual capabilities. There are huge gaps here, and the hypothetical I somewhat carelessly threw out might only be one of many.
That said, I agree with you that telepresense could have tremendous leveraging power on the moon, or thoughout cislunar space.
OK. If we cast the ingots into the same soft-ball size and shape of the High Frontier sintered soil balls, I suppose the same size m***-driver could launch them. The only difference between this proposal and the High Frontier one would be that in the original proposal both the ore refining and metal working components were in HEO, whereas here the refineries would be on the lunar surface and only the metal working facilities would be in HEO.
In which case, what is the advantage of refining the ore on the moon? The participants of the Summer Study gave what they felt was a very good reason for not putting the ore refinery in a place which was cut off from solar power for 2 weeks out of every 4. What is the even more compelling reason for ignoring this advantage? You started by saying an advantage was you didn't have to wait on the m***-driver to start processing ore, but since you have to wait on it before working metal, I don't see the point.
Sander's point is that if launching up refined materials instead of ore, one could get by with launching less. This is true, but if we have a requirement for shielding humans in orbits above the geomagnetic field, and had no slag from orbital ore refineries available, we would wind up needing to launch an equivalent m*** of some material anyway. Sander counters this by denying that we'll have much need for humans in this process.
The difference in thinking between you and the Summer Study is that they concluded there would be no need for parts maunfacturing on the moon at the onset of the project. The components for the m***-driver launcher would be a kit created on Earth and ***embled on the moon. They didn't recommened parts manufacture on the lunar surface until M***-Driver 2 was needed.
There's a bit of circular logic here. Because you're tending to think in terms of industrial development on the lunar surface, you're seeing a need for "specific parts" manufacture there, and then using that need as justification for industrial development on the lunar surface.
For the half dozen reasons given by the NASA-Ames Study.
If there come to be some extraordinary advances in telepresence such that the requirements for humans in HEO declines to some number less than a couple dozen or so, I can see the need for radiation shielding in orbit declining markedly from High Frontier expectations. It must be granted that in such a scenario, launching metal ingots up from the moon would mean less m*** being sent up from the moon overall. But this must be weighed against the disadvantages of not being able to carry out solar-powered ore refinement half the time. Plus the additional costs of soft-landing the ore refineries on the lunar surface.
If in the long run we decide to build ore refineries in HEO to capitalize on the continuous availability of solar power, then the only redundancy will have been in building ore refineries on the lunar surface before they were needed.
As far as I can tell, you and Sander are pushing for lunar surface industrial operations simply because you want to industrialize the lunar surface. The Summer Study was only concerned with getting SPS built from lunar resources as quickly and efficiently as possible, and was perfectly happy to put off industrialization of the lunar surface for a later point.
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
Hop David hopspageHATESSPAa...@tabletoptelephone.com
The summer study? Google is giving too many hits to sift through. Could you provide a specific URL?
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Hop David http://clowder.net/hop/index.html
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
He's referring to this: http://lifesci3.arc.nasa.gov/SpaceSettlement/75SummerStudy/Design.html
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
RobertM ...@YahooGroups.Com
What about the polar regions where a solar collector could be mounted on the rim of a crater, where it gets sunlight virtually all the time?
Have we conducted surveys that show no such location exists?
If you put the mining station anywhere else, you have power to mine and power to launch only 2 weeks out of 4, so the orbital processing stations have no raw materials to work with half the time and must work extra fast to catch all the stuff coming up the other half the time.
Is the claim that 50% duty cycle for surveying and mining and launching is quite sufficient to keep the processing factory busy 100% of the time so it can actually make use of that 100% sunlight available?
It'll take some time to develop the methodology for refining the ore.
During that whole time, there's no use for a launcher or catcher or metal-working. So you can install the mining and processing stuff first, and only later need to install the m*** launcher and metal-working. In fact you can install the survey stuff first, without any mining or processing, then later install the mining and just collect the stuff in a pile, then shortly later install the processing, and much later finally install the launcher and catcher. So each budget year you have spent only a portion of the total, and have some results to show for it, so you can get the next increment of funding. But if you launch raw materials, you need both mining/processing and launcher simultanously at the very start, requiring more money up front before anything at all has been proved. And even so you can't start metal-working until much later when the processing is working properly, so for the final product you gained no time compared to processing on Luna.
I'm not sure what is meant by "onset" here. At the very beginning of the project, we don't yet know where to find raw materials of specific compositions, and we don't yet know in practice how to mine the materials and transport them to a specific place (processing station or m*** launcher), and we don't yet know how to process them to yield useful materials, so we can't even consider starting to manufacture parts any time soon, so this point is moot when comparing Lunar processing and later launch with launch and later on-orbit processing.
At the present time we don't even know the nature of the apparent hydrogen source in the polar regions, whether we'll be able to harvest hydrogen easily or not. So we don't know whether it'll be best to mine in the polar regions, where hydrogen is abundant, or in non-polar regions where KREEP or other valuable resource is more readily available, during the first years when we can't afford to mine more than one place on Luna. I think we need to survey the polar regions, and then actually try mining any wet regolith we find there and try extracting the hydrogen, to see if it's really easy or not. If we learn that it's indeed easy, it seems better to continue that processing on Luna rather than abandon the processing and re-build it in orbit. On the other hand, if there really is no accessible hydrogen in the polar regions, then maybe the Summer Study method would be best.
"Mike Combs" mikeco...@nospam.com_chg_nospam_2_ti
But the Summer Study didn't see any problem with at least the first m*** launcher being produced entirely on Earth.
I certainly would never argue that we should proceed without further study.
But then the other part of the proposal is m***-driver launch to the L-2 point. I don't think you can do that from a pole.
Seems like I recall reading that the ESA did a survey concluding there were 3 peaks at one of the poles where if they were wired together could produce electricity over 90% of the time.
This proceeds from the ***umption that the throughput of the m***-driver is equal to the throughput of the ore refineries/fabrication shops. I don't think that's the case. Did you see my other posting where I commented on the early nuclear reactor that was later gone?
I believe that to be the case.
I think the difference between your thinking and mine (and I suspect, the Ames study as well) is that I expect we'll pretty much have the ore refining methods worked out here on Earth using lunar simulants before we commit to any lunar surface operations. I don't think we're going to go to the tremendous expense of going to the moon, and only then start monkeying around to see if we might can cook up something which might actually work.
I think any results which are short of what you need where you need it doesn't do us any good (other than perhaps providing a psychological boost).
Either the entire enterprise is worth funding in its entirety, or we should do something else with the money instead.
But I think "much later" in this context means a few days. I can't see any reason why it should take more than a few days to refine ore. Unless an alternative scenario can make a difference of several years, I don't see the point.
On the other hand, we can gain time by capitalizing on the continous sunlight available in HEO via continous operation of our ore refineries and metal working plants. That time gain is ongoing and continuous for the entire length of the era in which we use lunar materials in space.
The Summer Study ***umed use of surface material no different from what Apollo picked up and brought back. I'm sure there'll be a certain amount of prospecting with an eye toward increasing efficiency, but in a pinch we can just start shoveling up what's next to the m***-driver, and get by. The NASA-Ames Study didn't ***ume anything more involved than that.
On the contrary. The difference between your thinking and theirs was that they ***umed all of these problems had to be worked out in advance before there could be any kind of a commitment to start. I can't see us talking an investor into flying us to the moon, and then, once there, we'll start work on seeing if we can figure out any solutions to these problems.
BTW, I'm open to the possibility of the unexpected requiring us to think fast and modify our methodologies as we go. I'm just questioning this ***umption that we have to get to the moon first before we can even begin to work out the broad outlines of how we're going to do things there.
Gets my vote. H2O extraction might be the low-hanging fruit here, and would see immediate application.
It only seems better to someone who's pulling for lunar surface operations because they're into the idea of lunar surface operations.
First, I don't think you've presented any truly compelling reasons for ore processing or metal working to start on the moon first and HEO second rather than the other way around. Second, even if we did it that way, and we are to some extent duplicating our effort on the lunar surface in HEO, it might still be worth doing for all of the advantages of orbital processing cited in the Ames study.
To me, the presense or absence of lunar hydrogen only makes one difference in this scenario, and that's on the original ***umption that all of the water we need to make in HEO has to come from lunar-derived oxygen but Earth-derived hydrogen.
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Regards, Mike Combs
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Member of the National Non-sequitur Society. We may not make much sense, but we do like pizza.
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