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#101 2016-09-17 17:12:14

Void
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Registered: 2011-12-29
Posts: 1,806

Re: What is the status today of O'Neill's vision today?

I guess that's why we communicate, because someone else may think of something more.  Yes, ideas.  But I will let you champion your own interests.

As for myself, I asked for the gravitation of Ceres, as an arbitrary selection originally.  Might as well find out what is a tolerable or ideal gravitational environment for working, particularly with large objects.  Yes indeed.

For my part now, however, I see that we have some options to support.  Luna & Ceres, or Mars, or Venus.

One of these schemes is likely to be the winning ticket, if effort is applied to it.

For Mars, I have misgivings.  I have long had a conspiracy suspicion that the reason that our space program was diverted from the Moon to Mars, was that the conspirators were worried that we were getting too close to success.  With Mars, they have options to cut the process short, either by claiming the protection of life, or by cutting the budget, or arranging for a dead crew.

Of course that is the paranoid view.  It would require a class of people who live by manipulating populations, and their objective in this case would be to capture the spinoffs of the process, but to cut short the process when it threatened to set their servant class free from their power. 

And I am not totally paranoid, I just list it as a possible reality.

So, the cycling spaceship proposed with Ceres & Earth/Mars/Moon synthetic gravity, would be a purpose in itself, but could also be assistive in settling Mars itself, if that is allowed, or if Mars is said to have life, it could allow human access to the moons of Mars to study that life on Mars.

But it would also study how to use Luna & Ceres, if Mars is ruled off limits for humans.

Ceres itself appears to not be as I thought it would be. 

Instead it is not completely differentiated, so the crust it seems may be 60% soil/rock & 40% ice.

And its materials include Nitrogen.

So, Ceres has a very large palate of the materials one would want in space.

Therefore, in considering O'neill machines, perhaps one should consider all possible understood future options, or as much as possible.

If you could do the Ceres & Earth/Mars/Moon gravity synthesis on such a cycling spaceship then you could also do it on Ceres, but you would not need synthetic gravity for Ceres itself, since it supplies that.  You would instead want a network of double torus devices with Earth/Mars/Luna synthetic gravity, and greenhouses under Ceres ambient natural gravity.

It should not be forgotten how relatively easy it would be to export materials from Ceres, once humans were established there.

For instance Ice.  I have no references, but I believe that you can crash a block of ice onto the Moon on the dark side at very high speed, and probably 60% of it will remain long enough to be collected.

Therefore if we are blocked from using Mars, Luna & Ceres would be quite a good objective.  And cycling spaceships?  Why not?

Last edited by Void (2016-09-17 17:28:45)

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#102 2016-09-17 18:51:52

Tom Kalbfus
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Re: What is the status today of O'Neill's vision today?

You ever see this movie?
http://www.bing.com/videos/search?q=O%2 … ORM=VDFSRV
What do you think? It is a variation on O'neill's idea with artificial illumination of the interior. I wonder how close one can get to those light sources without getting fried? My guess is they are giant florescent light tubes or LEDs, what do you think? In the middle of it is a model of the island of Manhattan and its surrounded by countryside. Not a soul is to be seen, although the fields appear to be cultivated. One can see the Twin towers in the model of Manhattan.

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#103 2016-09-17 19:08:04

Void
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Registered: 2011-12-29
Posts: 1,806

Re: What is the status today of O'Neill's vision today?

That is certainly a good dream, and so it would seem your heart has value.

Strange, you have New York +, and also wide spread farm fields as some of your re-occurring notions, your reference points.

My background has to do with figuring out how to run your life without extreme guidance from a hiearchy.

That in theory is how Americans are supposed to be.  Some of our highest politicians seem to love to criticize people like me because we do not want to associate with predatory cultures such as the very old world.  (Those cultures in my opinion only run on hierarchy).  To me they are deadly poison.  Like being forced to co-exist with rotting corpses of the living dead.

I suppose I had better get to a point.

In my mind there is no chance that the sort of people we are dealing with as enemies these days would leave such a machine unmolested.  They are creatures that crave power and control.  So, a wonderful dream, but only if somehow you can keep the demons out.

It is a wonderful aspiration however! smile

And that is why I prefer smaller work oriented machines, where a small community pulling together to accomplish a profitable living.  Such communities are less likely to foster degenerates of the sort that crave control of large populations.  Rather such an environment will favor people who manipulate physical objects for profit, not other people.

Last edited by Void (2016-09-17 19:29:56)

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#104 2016-09-17 22:13:08

Void
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Registered: 2011-12-29
Posts: 1,806

Re: What is the status today of O'Neill's vision today?

And terraformer said before our B.S. Avalanche:

Before all that, I'd like to find out how much gravity is required for plumbing to function normally. Now *there's* something we can do using parabolic flights, without needing to go into space at all.

If it turns out 0.1g is sufficient to be make a lot of things significantly easier to do, even if it doesn't provide much health benefits, then we could look at sending some small, ~8m diameter centrifuges to whatever space station we're using at that time.

A very important question terraformer.  That, and what is the need to maintain health benefits.

The ideal work place gravity field.

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#105 2016-09-18 06:02:18

Tom Kalbfus
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Posts: 4,401

Re: What is the status today of O'Neill's vision today?

Void wrote:

That is certainly a good dream, and so it would seem your heart has value.

Strange, you have New York +, and also wide spread farm fields as some of your re-occurring notions, your reference points.

My background has to do with figuring out how to run your life without extreme guidance from a hiearchy.

That in theory is how Americans are supposed to be.  Some of our highest politicians seem to love to criticize people like me because we do not want to associate with predatory cultures such as the very old world.  (Those cultures in my opinion only run on hierarchy).  To me they are deadly poison.  Like being forced to co-exist with rotting corpses of the living dead.

I suppose I had better get to a point.

In my mind there is no chance that the sort of people we are dealing with as enemies these days would leave such a machine unmolested.  They are creatures that crave power and control.  So, a wonderful dream, but only if somehow you can keep the demons out.

You are not going to build this without Artificial Intelligence, there is a reason why the streets are vacant, and the landscape is empty, humans haven't moved in yet! That is why at the end of the movie, you see a space shuttle approaching.

It is a wonderful aspiration however! smile

And that is why I prefer smaller work oriented machines, where a small community pulling together to accomplish a profitable living.  Such communities are less likely to foster degenerates of the sort that crave control of large populations.  Rather such an environment will favor people who manipulate physical objects for profit, not other people.

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#106 2016-09-18 07:34:27

Void
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Re: What is the status today of O'Neill's vision today?

Well Tom, this will be a pointless argument if we go down that path.

We do not really know what A.I. will be like.  Therefore your assertion that it will comprise a benovelent and competent protector of such a giant machine is not testable at this time and all we really could do is make tiresome counter assertions.

I will say that even now computers are hacked.

Also when multiple life forms interact, they always seem to split into groups, and eventually one group becomes the prey, and the other the predator.

But again we do not know what such A.I. will be like.  If they are not like humans, then they might behave in an insane manner from our perspective, and that could be quite dangerous to the continuation of our patterns.  If they are like humans, what have you gained?

I don't think I will talk on this subject anymore because the argument presented is untestable at this time.  It would be an exasperating interaction.  Already is.


Terraformer;

I suggest you start a new topic dealing with your question on the ideal work functional (Plumbing) synthetic gravity.  Otherwise it will just die here.

Last edited by Void (2016-09-18 07:39:13)

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#107 2016-09-18 09:47:01

Tom Kalbfus
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Re: What is the status today of O'Neill's vision today?

I'll just say this, if AI destroys us, then all the talk about building space colonies will be moot, if it does not, then they'll be needed, even Gerard O'Neill assumed as much. He assumed that his larger colonies would be build with robotic workers and that he population density would go down as a result, and that was back in the 1970s when he said this, he said that his O'Neill Cylinder Island Three could support a population of up to ten million people, but because of all the robot labor involved in its construction, it probably wouldn't have to, that is also why his colonies, when depicted in art have that "suburban feel."
de_omgekeerde_wereld.jpg
space.colony.jpg
This is not a teaming metropolis you see here. Who would build such a thing? You see a town off in the distance. I think if it was built entirely by humans, it would b jam packed with skyscrapers, you wouldn't get such a rural landscape as depicted here.
The top one is similar to the cylinder depicted in Rama.
rama.jpg

Last edited by Tom Kalbfus (2016-09-18 09:51:17)

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#108 2016-09-19 08:24:50

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
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Re: What is the status today of O'Neill's vision today?

Addressing the issue raised by Terraformer:  how much gravity is required to make conventional infrastructure like toilets work? 

Without actually having attempted such,  I think it's a matter of time constant you can tolerate.  The dynamics and fluid dynamics of all sorts of processes slow down in low gravity.  We've already seen a little bit of this during the moon landings. 

In a water treatment operation for example,  the bubbling and settling operations are going to need much larger exposure or residence times as gravity weakens. 

Such things would be very slow on Ceres with 2% class gravity,  but if you can tolerate the slowness,  conventional stuff should work even there.  If in some process,  slowness is intolerable,  then you have to devise something that will accomplish the function some other way. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#109 2016-09-19 09:24:57

Tom Kalbfus
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Re: What is the status today of O'Neill's vision today?

On Ceres you would need much bigger toilets to generate the water pressure under 2% gravity. Also under low gravity toilets would flush more slowly, you would need more water to get the same job done of removing the waste. I rather think it would get quite messy with water and fecal matter splashing out of the bowl in slow motion when you flushed it! You probably would need a deeper bowl so the water and what you put into it wouldn't splash out!

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#110 2016-09-19 12:11:02

Void
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Registered: 2011-12-29
Posts: 1,806

Re: What is the status today of O'Neill's vision today?

Nice.

I guess we want to segregate our eating, breathing, and emissions behaviors.  In this case, it is a good thing to do.

Ceres if rehearsed with O'neill artificial hab methods, would reveal if Ceres itself could be successfully and prosperously habituated.

It could also contribute to the distribution of humans to Venus and Mars and Luna as well.

So, I am interested in a two level synthetic gravity for such artificial habs.

If it works out, then perhaps a great deal of the surface of Ceres could be simply habed, with some of it being natural Ceres gravitation, and some with multiple centrifuge rings, linked together, to allow a very flexible life style for the inhabitants.

Such a Ceres, if possible/practical, could become a hub for an early solar system civilization.

A place for human spiritual growth as well, I think if the material needs are satisfied.

Last edited by Void (2016-09-19 12:21:36)

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#111 2017-05-15 08:13:46

Antius
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From: UK
Registered: 2007-05-22
Posts: 842

Re: What is the status today of O'Neill's vision today?

O'Neill's vision for solar power satellites is the only remotely plausible suggestion I have seen for space colonisation.  Not because of the enormous space colonies he proposed, but because it involved producing something that could be sold to folks back on Earth, something that had enough value and sales volume to fund the sorts of investment needed.

O'Neill's vision is more plausible today than it was in 1976.  As a start-up, the lunar side of the operation could be largely automated or teleoperated.  It could start small and gradually increase in scale as more money comes in.  The most massive component of the lunar base is the power supply to the mass driver.  Space solar power systems are much lighter now.  According to Louis' recent information, power-weight for solar power may soon exceed 1Kw/kg.  Mass drivers would also benefit from super-capacitors.

The space based operation would also be a lot more streamlined.  In 1976, O'Neill was talking about building solar dynamic power plants which would have required a lot of moving parts and working fluids.  A 10GW station would have weighed a hundred thousand tonnes.  Now, the satellites would be thin film PV, would have a minimum of moving parts and a 10GWe satellite would weigh perhaps 10,000 tonnes.

The mega fantasy space colonies are something for further into the future.  In the near term, an SPS manufacturing operating can be started as a relatively small scale effort, using compact facilities making use of 3D printing of simple repeatable components.  Build-up of facilities can occur incrementally as more SPS sales come in.

Last edited by Antius (2017-05-15 08:40:21)

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#112 2017-05-15 12:45:12

Terraformer
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From: Atlantis
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Re: What is the status today of O'Neill's vision today?

I wonder if very thin film solar cells could be used with coverings manufactured from Lunar resources? So Lunar glass would be used to protect them from degradation, with the only thing being imported from Terra being the ultra-thin cells which would be attached to the rest of the satellite in orbit.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#113 2017-05-15 13:30:55

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 4,797
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Re: What is the status today of O'Neill's vision today?

Antius wrote:

O'Neill's vision for solar power satellites is the only remotely plausible suggestion I have seen for space colonisation.  Not because of the enormous space colonies he proposed, but because it involved producing something that could be sold to folks back on Earth, something that had enough value and sales volume to fund the sorts of investment needed.

Solar Power Satellites are a dumb idea that has already been debunked. Sorry.

Start by asking: Why space? Why not solar power on Earth? The advantage to space is no clouds and no night. But the best power transmission technology has been able to deliver 30% of power transmitted. Solar power on Earth can do just as well. On Earth there's no power from solar roughly 50% of the time due to night, and more power loss due to clouds. That results in about the same. Building a solar power system on Earth requires a truck to deliver parts, and repairs require a technician in clothing driving a pickup truck. Building one in space requires a multi-million dollar launch vehicle, and repairs require an astronaut in a spacesuit delivered via spacecraft launched by another launch vehicle. Ground based solar is a lot more cost effective.

Next look at technology. I keep talking about a paper I read in year 2000. A US federal government laboratory called the Los Alamos National Laboratory did a theoretical study and found a new photovoltaic chemistry that should have a solar absorption spectrum that almost perfectly matched the Sun. So it should be extremely efficient. They looked for someone to build one for them, so they could see if reality matched their theory. They went to the materials lab at the University of California in Berkeley. They found it does work, and it's transparent to any frequencies of light (colours) that it doesn't convert to electricity. That shouldn't be a big surprise considering space photovoltaics already use 3 junctions (sub-cells), the top 2 are transparent to colours they don't absorb. The top junction of current space cells is gallium-indium-phosphate, this new one is gallium-indium-nitride, so only the doping agent is different. Furthermore, the absorption spectrum can be shifted by using a different concentration of nitride. Current space cells use a different chemistry for each junction (sub-cell), but this new one allows each sub-cell to use the same chemistry, just a different concentration. U.C. Berkeley found a 2 junction cell produces 56% conversion of sunlight to electricity, 3 junction 64%, and 36 junction 72%. Another scientists studied this and produced optimized junction combinations for 2 through 8 junctions. He found the same results for 2 and 3 junctions, and 8 junctions would produce 70.2%. One excuse this hasn't been developed is implanting nitrogen deeply enough into the cell, but every blue LED is gallium-indium-nitride just with a different configuration. And every white LED is actually 3: red, green, blue. So every LED light you have already has this, implanting nitrogen has already been solved.

Build a house with the entire roof as one big solar array. Not just a couple small solar panels attached to the roof, the solar array *IS* the roof. Include a geothermal heat pump (aka ground source heat pump), windmill, batteries, and the house is 100% energy independent. Size the system for the worst case in that city or location, the rest of the year the house will sell surplus power to the grid. So no heating bill, no electricity bill, instead the power utility pays the home owner. This won't work in high-rise buildings such as apartment buildings or downtown office buildings, but those are the customers who will buy the power.

This is far more practical than solar power satellites.

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#114 2017-05-18 08:27:37

Antius
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From: UK
Registered: 2007-05-22
Posts: 842

Re: What is the status today of O'Neill's vision today?

RobertDyck wrote:
Antius wrote:

O'Neill's vision for solar power satellites is the only remotely plausible suggestion I have seen for space colonisation.  Not because of the enormous space colonies he proposed, but because it involved producing something that could be sold to folks back on Earth, something that had enough value and sales volume to fund the sorts of investment needed.

Solar Power Satellites are a dumb idea that has already been debunked. Sorry.

Start by asking: Why space? Why not solar power on Earth? The advantage to space is no clouds and no night. But the best power transmission technology has been able to deliver 30% of power transmitted. Solar power on Earth can do just as well. On Earth there's no power from solar roughly 50% of the time due to night, and more power loss due to clouds. That results in about the same. Building a solar power system on Earth requires a truck to deliver parts, and repairs require a technician in clothing driving a pickup truck. Building one in space requires a multi-million dollar launch vehicle, and repairs require an astronaut in a spacesuit delivered via spacecraft launched by another launch vehicle. Ground based solar is a lot more cost effective.

Next look at technology. I keep talking about a paper I read in year 2000. A US federal government laboratory called the Los Alamos National Laboratory did a theoretical study and found a new photovoltaic chemistry that should have a solar absorption spectrum that almost perfectly matched the Sun. So it should be extremely efficient. They looked for someone to build one for them, so they could see if reality matched their theory. They went to the materials lab at the University of California in Berkeley. They found it does work, and it's transparent to any frequencies of light (colours) that it doesn't convert to electricity. That shouldn't be a big surprise considering space photovoltaics already use 3 junctions (sub-cells), the top 2 are transparent to colours they don't absorb. The top junction of current space cells is gallium-indium-phosphate, this new one is gallium-indium-nitride, so only the doping agent is different. Furthermore, the absorption spectrum can be shifted by using a different concentration of nitride. Current space cells use a different chemistry for each junction (sub-cell), but this new one allows each sub-cell to use the same chemistry, just a different concentration. U.C. Berkeley found a 2 junction cell produces 56% conversion of sunlight to electricity, 3 junction 64%, and 36 junction 72%. Another scientists studied this and produced optimized junction combinations for 2 through 8 junctions. He found the same results for 2 and 3 junctions, and 8 junctions would produce 70.2%. One excuse this hasn't been developed is implanting nitrogen deeply enough into the cell, but every blue LED is gallium-indium-nitride just with a different configuration. And every white LED is actually 3: red, green, blue. So every LED light you have already has this, implanting nitrogen has already been solved.

Build a house with the entire roof as one big solar array. Not just a couple small solar panels attached to the roof, the solar array *IS* the roof. Include a geothermal heat pump (aka ground source heat pump), windmill, batteries, and the house is 100% energy independent. Size the system for the worst case in that city or location, the rest of the year the house will sell surplus power to the grid. So no heating bill, no electricity bill, instead the power utility pays the home owner. This won't work in high-rise buildings such as apartment buildings or downtown office buildings, but those are the customers who will buy the power.

This is far more practical than solar power satellites.

Robert, I cannot comment on your information regarding recent solar cell improvements, as I am not familiar with multi-junction research.  But your assessment of microwave power transmission is somewhat subjective.

The efficiency of beamed microwave power transmission is a function of the relative sizes of the antenna and rectenna, their distance apart and the frequency of beam.  A frequency of 2.45GHz appears to be optimum in terms of minimising interaction with Earth’s atmosphere, but requires a relatively large rectenna (~10km in diameter) in order to avoid efficiency loss due to beam diffraction.  Because of these variables, the transmission efficiency through the Earth’s atmosphere is dependent upon the scenario.  This Chinese reference estimates transmission efficiency to be ~66%.

http://www.sciencedirect.com/science/ar … 6516310013

An experiment carried out by Raytheon under the supervision of JPL in 1973, demonstrated a DC-to-DC conversion efficiency of 54%.

http://ieeexplore.ieee.org/document/113 … eload=true

Whilst transmission losses are relatively high, it must be remembered that only about 60% of sunlight hitting the top of Earth’s atmosphere reaches the surface, about 70% across the visible spectrum.  So arguably, the real efficiency of an SPS is about 80-90% of the same solar power system on the ground.

There are three big advantages that an SPS has over a ground based system:
1.    It is in full sunlight for 99% of the time.  It therefore gathers roughly three times as much solar energy as the equivalent area of panels at Earth’s equator.  For a North European country, it would be exposed to 8-12 times as much energy in 1 year.  If dynamic cycles are used, the advantage is greater still.
2.    There is no intermittency, aside from the 1% of time in Earth’s shadow.  That is a major advantage, as renewable energy systems here on Earth require a combination of energy storage (which is inefficient) or back-up power, which basically means having a whole extra power station on standby to cover the downtime.  With the SPS, some 72 minutes of back-up would be needed and it would be required at predictable times.  Open cycle gas turbines can do this cheaply and with negligible impact on whole system efficiency.
3.    In space, without wind or gravity, the structure of the power plant can be relatively slender.

Collectively, these advantages are significant.  But the economics of the concept clearly rely upon the ability to use extra-terrestrial resources for manufacture of the satellite.

Last edited by Antius (2017-05-18 08:30:26)

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