I’ve noticed that Columbus Day is not as…celebrated… these days as when I was a kid, when it was pretty much an unalloyed paen to the great explorer and navigator who thought that the planet was a lot smaller than it was, bumped into a convenient continent in between Spain and Asia (had it not been there, the expedition would have been lost, or the crew mutinied and return home, long before they arrived at the real Spice Islands). Fortunately for him, the power of self delusion is great, and he seems to have gone to his deathbed thinking that he found a new route to the Orient, albeit one that bore no obvious resemblance to the one being traded with previously, other than full of heathens.
Anyway, the holiday seems to arouse much more protest today than in the sixties, at least among the politically correct and bien pensant, many of whom think that colonizing and industrializing the continent was the worst thing to happen to not only the people who had already been living here (and despite Rousseau’s toxic delusions about savage nobility, pillaging and making war amongst themselves, torturing and human sacrificing, and slaughtering the fauna who had beaten them here), but the entire planet.
I’m somewhere in the middle, but more old school than new. Certainly the place could have done with a lot less slavery and gold digging in the name of the Lord, and it would be a happier, or at least more productive place had both the north and south been Anglicized, rather than feudalized by Spain and Portugal, but overall I think that we’ve been better stewards than the first plunderers were, having gained a lot more scientific (as opposed to faux spiritual) knowledge and developed technologies to make things more to everyone’s liking, for all their cavilling. I don’t, after all, see the natives doing much of that return-to-the-earth stuff — they find casinos much more lucrative. That seems to have been left to their worshipers in communes and academia, who seem to worship them even when they are fake but accurate. And it’s tragic that so many died from simple contamination by diseases to which they had no immunity (though not deliberately for the most part, despite that particular mythology), but this is another area in which we may learn from the past, and at least try to minimize such future events.
Which gets me to my real point.
In reading some of the comments over at Pop Mechanics today, I was struck (on this day) by how many in the space advocacy (and non-advocacy) community continue to use the opening of the New World as an analogy for where we are today, or are going, in space. For instance, Jeff Greason:
I think Mars is a very obvious place for settlement to happen. It is the place we have that is closest to us and looks like the most prominent candidate for a self-sustained human presence. Why would anyone want to go there? I want to go! There are lots of people out there who want to go. Wind that question back 400 years. Why would anyone want to go this great howling wilderness in North America? When the pilgrims got here, they wrote about what inhospitable place it was, with no inns to refresh one’s spirits, nothing but howling wilderness. The first three attempts to make a permanent place in the Los Angeles area ended in death. Even now, you have to pipe in water to survive. We had to master fire to get out of Africa, and agriculture to get to a lot of places. The American West had to be subjected to massive civil engineering works before more than a small community of pioneers could live there. What you consider to be habitable is a function of your level of technology.”
This is an argument that I (and countless others) have made in the past. And then we have the inevitable Bob Park:
When we established colonies [on Earth], we did it for very specific reasons. To rape the resources and bring them home. There aren’t any resources on Mars, not that we know of. There’s nothing to go there to get. If there were diamonds a feet deep on Mars, it still wouldn’t be worth the cost of sending people there. We’re already doing a great job with unmanned explorers.
That last, of course, always begs the question of what “the job” is.
So is it a good analogy or not? Yes, in some ways, no in others. As Scott Pace notes, our future in space depends on two critical issues, and one can build a quadrant table from them:
| Can Live Off The Land | Can’t Live Off The Land | |
| Economic Benefits | Space Settlements | Oil Rigs |
| No Economic Benefits | Antarctica | Nothing Much In Space |
| Can Live Off The Land | Can’t Live Off The Land | |
| Economic/Spiritual Benefits | Space Settlements | Oil Rigs |
| No Economic/Spiritual Benefits | Massachussets/Salt Lake City | Nothing Much In Space |
I was discussion Earth infrastructure that needs to be inspected that frequently. So if we have space based infrastructure that needs to be inspected that frequently, either you have people live nearby or you bring them in every couple of weeks. It’s a mode of maintenance that can’t really be sustained in space due to near future barriers to casual space travel.
We talk right past each other, Karl. You don’t need people living nearby, as in make their homes nearby. You need people who work nearby and are away from their homes for long periods of time. Like sailors, oil rig workers, Antarctic researchers, construction workers, etc. This might sound incredible to you, Karl, but there is no shortage of people who are quite willing to work for long periods of time away from home as long as they are well compensated. Indeed, many prefer that kind of work.
Yes. And that is a problem we only need to solve once. We probably go well past that basic threshold, evolving technology as we go, but it’s only a one time barrier.
I don’t recall ever suggesting that each and every colonist will have to start from scratch and learn everything all over again. I think I suggested that difficulties that have proven intractable here on earth might prove equally so in the much more severe environments of space.
In my view, we have a pretty good idea how to do it even in the real world once we get cost of access to space down enough.
We all have views.
Your evidence contradicts your suggestion. For example, you keep attempting to use Canada as an example. It’s populated and the population increaseses by 0.8% a year, there are people living everywhere. It doesn’t support your suggestion.
Note I spoke of particular regions of Canada; specifically the subarctic. So when does Canada’s population approach that of the US? When does the Yukon achieve provincial status?
You said it “might never evolve”. I was addressing that condition in which it never evolves. After all, if technology continues to evolve then you don’t have an argument.
I said: “My point is that it technology might not ever evolve to the point at which they are available off planet, just as it hasn’t in the cases of various locations here on earth.”
I didn’t say technology never evolves; I said it might not produce a particular, desirable effect, just as it hasn’t in other cases. Technology is not a genii; we don’t have flying cars, electricity from nuclear power still must be metered.
It isn’t worth the effort to consider the situation where your argument is wrong by initial conditions. So what are examples of technology not evolving, especially with respect to extending human habitat? I obviously can’t think of an example.
Technology has evolved tremendously since the neolithic era. Human habitats remain virtually unchanged in that period of time. Technology has enabled much greater numbers but not more places.
That would just be error on your part. It’s clear that the average man in a developed country now can afford things that his distant predecessors couldn’t. For example, a house or a car, the usual electrical appliances. That sort of thing. Simply raising the life expectancy of a person by a factor of ten would do the job, in my view.
Fine, you’re on record for the average man being able to afford a 150 room mansion someday. And yes, it is clear that we have capabilities that seemed magical 50 years ago and that we’ll have capabilities in 50 years that would seem magical now. “A sufficiently advanced technology is indistinguishable from magic” and all that. But it does not follow that a sufficiently advanced technology can produce any effect we might consider magical.
Moving on, there is a big difference between a 400 foot yacht (and the other current trappings of great personal wealth) and a colony in space.
Obviously.
Namely, that the former is intended to be expensive while the latter is expensive due to current economics.
I think 400 foot yachts are just as subject to economics as any other product or service.
I see no indications that the economics of space colonization will remain infeasible.
And you see no indication that the economics of subarctic Alaskan and Canadian colonization currently are infeasible. But they are.
The current folks paying for exploration and science in space (national govs and some universities) don’t count what tourist groups are proposing (or anything like other tourist ops I can think of) as exploration efforts.
The Planetary Society disagrees. Again, they said “exploration without science is tourism.”
Leaving that aside, why should I care what someone thinks “counts”? We were discussing whether space colonization is possible, not whether it “counts” as politically correct.
> But, aren’t the people who pay for “tourism” usually taxpayers?
> Doesn’t that mean they’re the same ones paying for those nations and universities?
Ah, NO!
Really — you don’t think governments get their money from taxpayers? Where do you think it comes from???
Universities get some of their money from private donors, but if you look further, you’ll find out most of them are taxpayers, also.
The thread started with the idea that the world spent X billion a year (I think $20B) a year on space, so if that much a year was spent in the space colony
You must be reading some other thread. The original post didn’t say that at all.
The Mil and commercials dominate the money, and they launch sats to Earth orbits. Your not going to be cost competative with sat makers on earth due to your remote location with high costs to ship supplies to you from builders etc.
Many locations in space are less “remote” from geosynchronous orbit than the Earth is. There’s no reason to assume it will cost more to ship a satellite from a space colony than from Earth.
For the mil, security and political interest demand in the nation constructions.
That’s nonsense. The US military has constructed bases in Germany, Japan, England, Iraq, Afghanistan — none of which are in the United States. And if you think military bases never lead to permanent settlements, try telling that to the residents of Fort Wayne, Fort Worth, etc.
For national programs like NASA there are political constraints, and again – how coul;d you compete with earth builders lower costs?
There’s no reason to assume that everything built on Earth will have lower cost. That’s as unrealistic as the Moonies assuming that Apollo on Steroids will immediately build a complete industrial infrastructure on the Moon. The truth is somewhere in between. There are a great many things we can do cheaper in space *once we have the ability to get to space cheaply and reliably*. The fact that the Von Braunians regard that as heresy is irrelevant.
Jim, let me put this way. You have made some variation of the argument that space colonization won’t happen. As evidence, you claim that some areas on Earth are sufficiently underdeveloped and unpopulated to prove your point. Setting aside that I disagree with that interpretation of evidence, you are making a claim that requires evidence. Because it is effective a proof of impossibility, the claim cannot be falsified in a reasonable time frame (unless we kill ourselves off first).
I do not claim that space colonization won’t happen. I do not think it will happen in the next 100 years, say. Beyond that, who can say?
What I claim is that enthusiasts haven’t made a compelling case that space colonization is feasible or practical in the near term.
In comparison, I have as evidence:
history of past human colonizations, some of similar extent to a large scale colonization of space.
What you have is evidence that human are very well adapted to conditions that are found in places on the planet earth; places that have been inhabited by humans since the stone age. The experience of humans in places on earth that they are not well adapted to does support the notion that space colonization is feasible.
Evidence that technologies necessary for space colonization continue to be developed at a steady pace. We also have a good grasp of what tools to use and problems to overcome.
Experience to date shows that the technology to support even a few humans in space is hideously expensive and that for every human in space you need tens of thousands on earth to support him. There is no evidence that anyone in space can produce value in space commensurate with the costs of keeping him in space. There is little evidence that this will change soon. And all this before even considering the matter of colonization; that is making one’s home in space.
Evidence that the cost of access to space, the single greatest obstacle is decreasing and can decrease considerably more than it has.
Whether it is the single greatest obstacle to space is not a fact only a belief. There are places on earth where access is trivial that can’t be colonized. And whether the costs of space access can ever be low enough to enable space colonization even if there were no other considerations is still very much an open question.
In other words, I have evidence that we are indeed progressing towards space colonization.
I find your evidence unconvincing.
I can’t prove that we can colonize space. We’d have to do so first. But I can prove reasonable progress to that goal which will have to suffice for today.
I think your emotional attachment to the subject clouds your judgment. Only my opinion, of course.
You can have the last word, Karl. When Rand brings the subject up again maybe we’ll have fresh arguments.
> Karl Hallowell Says:
> October 15th, 2009 at 11:38 am
>
> I don’t think a convincing case has been made that space colonization won’t
> happen on a large scale.== because our current efforts aren’t quickly leading
> to colonies, people are starting to entertain the idea that maybe it will never ==
> happen due to hypothetical technological reasons. But that’s a bizarre assertion to
> make given both the history of massive colonization on Earth ==
Agreed. Our tech is adaquate to build a space colony – but it would take a huge capital investment to develop adn field the trasnports, system and construct everything — and we’ve identified no existing economic way to justify it, adn make it self supporting.
However, as future technology (like fusion) lower transport and recover costs, perhaps would allow economic recovery of ore, and smelt and mill metal, oil, etc for export(?) to Earth markets. One that much infastructure is avalible in space, that might make the colonies a going cocern, and allow for heavy industry moving to space as welletc.
But right now – to soon, no killer ap.
==
> Moving on, there are a number of technology “game changers” that
> could happen as well. Longevity increase is one such. Even ignoring
> other technological advances, I see a factor of ten increase in life
> span as sufficient in itself to enable space colonization. ==
I don’t follow this. Just because you are going to live for centuries, doesn’t mean your going to be willing to twiddle your thumbs for a century while losing time and money. For example if it would take 300 years to get to another star – even if you could live that long it would make no sence to go there, since other faster ships launched in a century or two you would get there before the slow boat you could take now.
I do not claim that space colonization won’t happen. I do not think it will happen in the next 100 years, say. Beyond that, who can say?
This is far better than the indefinite statements you made earlier. By putting an explicit expiration date on your prediction, you make it something that can come true. I would add that I think this actually had a rather large probability of coming true.
What I claim is that enthusiasts haven’t made a compelling case that space colonization is feasible or practical in the near term.
That’s acceptable and a good point. You might be puzzled by my about face, but my point all along was that even if it’s not feasible now, I feel we’ve demonstrate through the ways I describe above that we can eventually, even if it takes a few centuries, colonize space. It may take a few lifetimes to get all the economic and technological bricks in place, but it will happen. I don’t see however a strong case for colonization occurring this century. A lot will depend on what happens in the next couple of decades, but my guess is that it’ll be slow and somewhat inconclusive, a pessimism I’ve had off and on since the late 90’s when I started to seriously consider this stuff.
As far as colonizing subarctic Canada, I still don’t see the point. Not only is it feasible, we did it. It doesn’t have the population density of other places, but there is a nontrivial, growing population and that is what colonization is about. It’s not uniformly distributing people over the entire world, both land and ocean.
I think 400 foot yachts are just as subject to economics as any other product or service.
The point of a 400 foot yacht is as an expensive status symbol. What will happen is that they’ll find other ways to add cost to the vehicle than merely making it longer. Maybe the entire boat will be engraved by skilled artists or they’ll add tidbits like a large aquarium stocked with rare fish. I’ll be able to afford the 400 foot yacht without the options, but I won’t be able to afford the handpainted one fourth scale, mahogany model of the roof of the Sistine Chapel in my boat or the replica of the Eiffel Tower, handmade by intelligent panda bears.
Cost of space travel and technologies will go down due to economies of scale. That’s just a consequence of high fixed costs and much lower variable costs. But luxury goods that stay luxury goods will find ways to add cost, because cost is an important part of owning the luxury good. Also it’s worth noting that yachts (aside from the monsters like the 400 foot yacht) and other luxury goods typically have much greater production rates than space vehicles and other doodads. And they have a strong lineage. Even if a yacht maker hasn’t made a 400 foot yacht before, they usually have considerable experience in making large yachts and centuries of engineering knowledge and designs to work off of.
> Edward Wright Says:
> October 15th, 2009 at 1:40 pm
>
>> The current folks paying for exploration and science in space (national
>> govs and some universities) don’t count what tourist groups are
>> proposing (or anything like other tourist ops I can think of) as exploration efforts.
> why should I care what someone thinks “counts”?
Because you were talking about money going to something and confusing it with something completely unrelated.
>>> But, aren’t the people who pay for “tourism” usually taxpayers?
>>> Doesn’t that mean they’re the same ones paying for those nations and universities?
>> Ah, NO!
> Really — you don’t think governments get their money from taxpayers?
They don’t pay tourists vacation bills with it.
===
>> The thread started with the idea that the world spent X billion a
>>year (I think $20B) a year on space, so if that much a year was spent in the space colony
==
>> The Mil and commercials dominate the money, and they launch
>> sats to Earth orbits. Your not going to be cost competative with
>> sat makers on earth due to your remote location with high
>> costs to ship supplies to you from builders etc.
> Many locations in space are less “remote” from geosynchronous
> orbit than the Earth is. There’s no reason to assume it will cost
> more to ship a satellite from a space colony than from Earth.
I didn’t say cost to ship it from the colony. I said the colony would not be cost competative. To bemore explict the delivered cost of the sat to the orbit from Earth would almost certainly becheaper then one built on the colony due to the colonies remote location.
Even if the colony was in the same area in space (say also in geosync) it likely would be uncompetitive.
>> For the mil, security and political interest demand in the nation constructions.
> That’s nonsense. The US military has constructed bases
> in Germany, Japan, England, Iraq, Afghanistan ===
They don’t contract for sats, fighters, etc from them.
>> For national programs like NASA there are political
>> constraints, and again – how coul;d you compete with
>> earth builders lower costs?
> There’s no reason to assume that everything built on
> Earth will have lower cost. ===
I waas assuming orbital satelights. Comsats, recon sats, Hubble 3, whatever.
How would they not be cheaper? Costs of labor, support infrastructure, supplies (manufactured goods), etc would be lower; and their are etablished supliers for the sats etc on Earth with experence. That all puts you at a huge competative disadvantage.
But right now – to soon, no killer ap.
I absolutely agree, Kelly.
I don’t follow this. Just because you are going to live for centuries, doesn’t mean your going to be willing to twiddle your thumbs for a century while losing time and money. For example if it would take 300 years to get to another star – even if you could live that long it would make no sence to go there, since other faster ships launched in a century or two you would get there before the slow boat you could take now.
At some point the technology is going to settle down. If faster ships could get you there sooner, then wait for the faster ships. But eventually you’ll reach a point where the faster ship just isn’t worth the effort. And it’s not necessarily a bad thing for someone to get there before you do. An interstellar system is a big place.
And for interstellar travel, I’d consider it if my expected lifespan was on the order of 10,000 years. A trip to Wolf 424 at its closest point, even traveling at the relatively slow speed of 0.01 c is on the order of 50 years (or maybe a century, if closest approach is 1 ly as Wikipedia claims). According to Wikipedia, that closest approach happens in 7700 years. It may not be the greatest of ideas, those two stars are, as far as I know, metal poor. But it is feasible for someone with that kind of time at their disposal who steadily invests a modest income over a few millennia into steady investments and enabling technologies.
I meant this to be an example of what longevity on its own can do.
> Karl Hallowell Says:
> October 15th, 2009 at 4:28 pm
==
>> For example if it would take 300 years to get to another star – even
>> if you could live that long it would make no sence to go there, since
>> other faster ships launched in a century or two you would get there
>> before the slow boat you could take now.
> At some point the technology is going to settle down. ==
Folks have been saying that for a few centuries.. 😉 .. I would not hold your breath.
>== eventually you’ll reach a point where the faster ship just isn’t worth
> the effort. ==
Really it is. If you take longer – you need a HUGE heavy ship, with more complicated tech adn nearly 10 fold larger crew.. It gets easier to just go faster.
Check out a old website I did for a group on the topic.
http://metalab.unc.edu/lunar/school/InterStellar/SSD_index.html
>== And it’s not necessarily a bad thing for someone to get there before you do. An interstellar system is a big place.
> And for interstellar travel, I’d consider it if my expected lifespan
> was on the order of 10,000 years. A trip to Wolf 424 at its closest
> point, even traveling at the relatively slow speed of 0.01 c is on
> the order of 50 years (or maybe a century, if closest approach is
> 1 ly as Wikipedia claims). According to Wikipedia, that closest approach
> happens in 7700 years.===
First I think we could do 0.4 of light with tech likely in the mid to late century..
http://www.ibiblio.org/lunar/school/InterStellar/Fuel_Sail_Class/default.html
..Late this century, with physicists thinking the nexty wav will be advances in spacial enginering (altering innertia or kinetic energy, maybe zero point energy for all we know) you’re best bet now would be for at least most of the speed of light in a century. The only way we could do faster then light (and far far freakier things) in 7700 years is we went extinct, and no way do I think thats likely!
> why should I care what someone thinks “counts”?
Because you were talking about money going to something and confusing it with something completely unrelated.
So? You started off by saying the markets didn’t exist. Now, you admit that markets exist they don’t “count” because you say they’re “unrelated” and don’t fit your definitions of “science,” “exploration,” etc.
Why should we discount markets that don’t fit your definitions?
> Really — you don’t think governments get their money from taxpayers?
They don’t pay tourists vacation bills with it.
They don’t? Who do you think pays the bills for all the astronauts NASA sends to ISS? (No, don’t bother to quibble and tell me “tourist” is a derogatory term reserved for astronauts who don’t work for the government. The fact is the government pays for them, whether you choose to call them astronauts, tourists, GS-13s, or ducks.)
To bemore explict the delivered cost of the sat to the orbit from Earth would almost certainly becheaper then one built on the colony due to the colonies remote location.
The fact that you’re certain of something does not prove that you’re prove correct. I could suggest some reading. Try Gerard O’Neill’s “High Frontier” and G. Harry Stine’s “Space Enterprise,” for starters.
> That’s nonsense. The US military has constructed bases
> in Germany, Japan, England, Iraq, Afghanistan ===
They don’t contract for sats, fighters, etc from them.
I thought they contracted with England for the Harrier jet. I also thought those satellites were launched using Russian rocket engines. Do you know otherwise?
What exactly do jet fighters have to do with space colonies? I thought we were talking about building bases in space, not jet fighters.
I waas assuming orbital satelights. Comsats, recon sats, Hubble 3, whatever.
You’re talking about military space as it exists today, which is equivalent to aviation in the early days of World War I. Those satellites are the equivalent of the crude observation planes. We expect our enemies to be sportsmanlike and follow “rules of the road,” and we’re shocked that China would develop the means to throw a brick at one of our sputniks.
That won’t last forever. Space will be militarized no matter what pacifists wish.
How would they not be cheaper? Costs of labor, support infrastructure, supplies (manufactured goods), etc would be lower; and their are etablished supliers for the sats etc on Earth with experence.
Compare the cost of building a space battle station from lunar or asteroid materials vs. materials launched from Earth. The cost of labor, etc. has very little do with it. You can’t hire minimum wage workers to throw mass into orbit.
> Edward Wright Says:
> October 15th, 2009 at 9:45 pm
>
>>> why should I care what someone thinks “counts”?
>> Because you were talking about money going to something
>> and confusing it with something completely unrelated.
> So? You started off by saying the markets didn’t exist. ==
The ones you claimed yes.
> Now, you admit that markets exist they don’t “count” because you
> say they’re “unrelated” and don’t fit your definitions of “science,” “exploration,” etc.
False.
==
>>> Really — you don’t think governments get their money from taxpayers?
>> They don’t pay tourists vacation bills with it.
> They don’t? Who do you think pays the bills for all the astronauts
> NASA sends to ISS?==
They are not tourists they are the staff to build ad operate the ISS.
>> To be more explict the delivered cost of the sat to the orbit
>> from Earth would almost certainly becheaper then one built
>> on the colony due to the colonies remote location.
> The fact that you’re certain of something does not prove that
> you’re prove correct.==
Its basic busness. Your colony, and space establismment you can consider for generations, is farther out from supplies, labor, high cost. Transport to it is more expensive then to current providers on Earth. Labor costs and support costs (i.e. the cost you have to pay in salary and other fees to support the communities around it.) obviously cheaper then building adn supporting a space colony.
>== Try Gerard O’Neill’s “High Frontier” and G. Harry Stine’s “Space Enterprise,” for starters.
>>> That’s nonsense. The US military has constructed bases
>>> in Germany, Japan, England, Iraq, Afghanistan ===
>>They don’t contract for sats, fighters, etc from them.
> I thought they contracted with England for the Harrier jet. ==
Nope, McDonnel Douglas developed a new higher performance version. Embarasing
>== I also thought those satellites were launched using
> Russian rocket engines. Do you know otherwise?
The RD-180s? P&W can make them – or they can buy and sell Russian ones. Not sure if any mill birds are launched on Atlas’ with Russian RD-180s.
> What exactly do jet fighters have to do with space colonies? I
> thought we were talking about building bases in space, not jet fighters.
No, we were talking about what part of the current market for space activities a Colony could successfully compete for. Given that, you could get some idea on what kind of funds you could project the economic basis for the colony could be.
>> I was assuming orbital satelights. Comsats, recon sats, Hubble 3, whatever.
> You’re talking about military space as it exists today, ==
Yes, we were talking about the current space market, or any near term market, that could form a economic bassis for a space colony.
> That won’t last forever. Space will be militarized no matter what pacifists wish.
True – once theres enough there to be worth fighting for.
>> How would they not be cheaper? Costs of labor, support
>>infrastructure, supplies (manufactured goods), etc would be
>> lower; and their are etablished supliers for the sats etc on Earth with experence.
> Compare the cost of building a space battle station from lunar or
> asteroid materials vs. materials launched from Earth.
Higher from lunar or Asteroid material. Check out the DOE report in the ’70’s comparing SSPS built exclusivly from Earth launched prefabracated parts vrs the Lunar>L-5 senerio. Far higher capital costs to develop and field thelunarmines, launch facilities, in space caters, smelting/milling/manufacturing facilities. And of course the cities and towns to hold the staffs to operate all the above.
O’Neill’s basic error was not looking into economies of scale where launch services are involved. He assumed advanced shuttles with a fixed operating cost per ton, and asume that the cost was driven by the gravity well. Then they figured that that was driving 90% of the SSPS program, so lunar material would save so much in lift costs, that it would bankroll the L-5 colony concept.
However Launch energy from Earth or Luna have virtually no impact on launch costs. Virtually all of current Earth to Leo costs are the capital costs and overhead costs for the launchers. The direct cost per flight – even with current gen launchers – is comparativly tiny. Its why you find if you go over the program costs that cost to GEO for a SSPS from Earth is Lower then from Luna. Worse for a Lunar mine or L-% colony. The level of launch from Earth forces you to build a CRATS grade craft, adn provides it with a market big enough to drive its costs to orbit far bellow that O’Neill assumed. Then if you redo the budget assuming the new CRATS RLV is launching ALL the mas to LEO, needed to move everything needed to GEO. You find lunar launched material keeps coming out more expensive.
>The cost of labor, etc. has very little do with it. You can’t hire minimum
> wage workers to throw mass into orbit.
No, min wage folks don’t operate high end machinery – not even on a significant construction site on Earth.
On some selected comments, Kelly:
Really it is. If you take longer – you need a HUGE heavy ship, with more complicated tech adn nearly 10 fold larger crew.. It gets easier to just go faster.
OTOH, ever scrap of that larger ship and every member of that crew will be valuable when you get where you’re going. But my view is that the task is far enough ahead that we’ll have an adequate selection of far better technologies to choose from. If there are exotic propulsion technologies available, then it’ll make sense to use those. I chose the 0.01 c target simply because it’s an achievable speed with near future technologies. I’m not dependent on great advances in propulsion technology, but I won’t turn my nose, when they show up.
Extreme longevity in itself is a sufficient enabling technology. Even if in the unlikely event that space technology doesn’t advance much in the next 7,700 years, if you can live that long, you can plan an expedition to another star system. Living to a few centuries should be sufficient for planning and carrying space colonization in the Solar System.
You find lunar launched material keeps coming out more expensive.
That doesn’t follow in the long term. The Moon has lower delta v to everything in the Solar System and no atmosphere. That means it’s easier to build launch systems that launch for the cost of (Lunar) energy. For example, we could deploy a tether system (using today’s materials) to L1/2 or launch by magnetic rail. I also suspect you’ll get better times to market (for everything except LEO) than launching from Earth.
> They don’t? Who do you think pays the bills for all the astronauts
> NASA sends to ISS?==
They are not tourists they are the staff to build ad operate the ISS.
You’re arguing around in circles: “Exploration” isn’t “a market.” “Tourism” isn’t “exploration.” “Staff” aren’t “tourists.” Etc. Etc.
It’s pretty obvious that human spaceflight is a substantial market, no matter how often you change words to try to keep your argument afloat.
Its basic busness. Your colony, and space establismment you can consider for generations, is farther out from supplies, labor, high cost. Transport to it is more expensive then to current providers on Earth.
According to your “basic business,” human beings could never move out of central Africa.
You’re assuming everything would be transported from Earth, which is as foolish as assuming that humans would always depend on supplies from the Rift valley of Africa.
> What exactly do jet fighters have to do with space colonies? I
> thought we were talking about building bases in space, not jet fighters.
No, we were talking about what part of the current market for space activities a Colony could successfully compete for.
No, the idea that current markets are the only markets that will ever exist is your hangup.
I suggested that military bases could evolve into space colonies. You went off about how that couldn’t happen because national security requires all military construction to take place in the US. Faced with the obvious counterexample of US bases all over the world, you changed the subject to jet fighters.
Which might be relevant, if I had suggested space colonies might evolve from jet fighters, rather than military bases. Of course, I didn’t, so why yammer about jet fighters?
> You’re talking about military space as it exists today, ==
Yes, we were talking about the current space market, or any near term market, that could form a economic bassis for a space colony.
There’s a big difference between “near term” and “what exists today.” No one can predict everything that will happen in the future. but assuming that it will be exactly like the present ensures that you will always be wrong.
> That won’t last forever. Space will be militarized no matter what pacifists wish.
True – once theres enough there to be worth fighting for.
Some people think America is worth fighting for. “Whoever controls space controls the Earth.” Why do you think China is developing a military spaceplane? It’s not because they think there’s nothing worth fighting for.
Higher from lunar or Asteroid material. Check out the DOE report in the ’70’s comparing SSPS built exclusivly from Earth launched prefabracated parts vrs the Lunar>L-5 senerio.
Kids today say the darndest things. 🙂
The DOE never even looked at extraterrestrial resources. Most of the study didn’t even concern engineering. That was only one volume out of a dozen or so. Most of it was devoted to socio/politico/cultural/environmental/disarmament types “researching” all the reasons why cheap energy from space was a terrible idea.
I suggest you get hold of a copy and read it.
Far higher capital costs to develop and field thelunarmines, launch facilities, in space caters, smelting/milling/manufacturing facilities.
Yes, and the capital costs of moving out of the Rift vallyet were far higher than staying there and remaining hunter-gatherers. That didn’t stop people from doing it. People *do* occassionally invest capital, you know.
> Karl Hallowell Says:
> October 16th, 2009 at 10:16 am
>>On some selected comments, Kelly:
>> Really it is. If you take longer – you need a HUGE heavy ship,
>> with more complicated tech and nearly 10 fold larger crew.. It gets easier to just go faster.
> OTOH, ever scrap of that larger ship and every member of that
> crew will be valuable when you get where you’re going.
Its better to increase your odds of getting there alive.
😉
> But my
> view is that the task is far enough ahead that we’ll have an adequate
> selection of far better technologies to choose from. ==
really, With 0.4C achievable nowish – you really can’t consider a future century or two were weernot doing better then that. If we haven’t advanced – were in trouble and were not going to be worrying about interstellar if we have serious problems.
==
> Extreme longevity in itself is a sufficient enabling technology.
> Even if in the unlikely event that space technology doesn’t
> advance much in the next 7,700 years, if you can live that long,
> you can plan an expedition to another star system. ==
Just because you can live that long – a multi-century flight -doesn’t mean your ship can. Its easier to go fast then last long.
😉
>> You find lunar launched material keeps coming out more expensive.
> That doesn’t follow in the long term. The Moon has lower delta v to
> everything in the Solar System and no atmosphere. That means it’s
> easier to build launch systems that launch for the cost of (Lunar) energy. ==
Delta-V isn’t a cost driver even now in Earth launch. Earth launch to LEO costs pennies per pound of energy to LEO. So cutting that by a factor of 20 doesn’t help you. (A nit that a lot of space advocates overlook.) Longer term it means les since power will be cvheaper and we’ll use better drives.
Now its possible some other economic factor could make lunar ore more desirable. Better ore, legal flexibility, cheaper ships or something. But all that’s kind of far future industrial trade offs.
> For example, we could deploy a tether system (using today’s materials)
> to L1/2 or launch by magnetic rail. I also suspect you’ll get better times
> to market (for everything except LEO) than launching from Earth.
You might want to run some numbers on that.
> Edward Wright Says:
October 16th, 2009 at 10:19 am
>>> They don’t? Who do you think pays the bills for all the astronauts
>>> NASA sends to ISS?==
>> They are not tourists they are the staff to build ad operate the ISS.
> You’re arguing around in circles: “Exploration” isn’t “a market.”
>“Tourism” isn’t “exploration.” “Staff” aren’t “tourists.” Etc. Etc.
No you just keep changing the def of terms when the numbers don’t add up. You can’t define what would be a base market to start or build a colony on.
> It’s pretty obvious that human spaceflight is a substantial market, ==
really, based on what? At what price point?
>> Its basic busness. Your colony, and space establismment you can
>> == is farther out from supplies, labor, high cost. Transport to it
>> is more expensive then to current providers on Earth.
> According to your “basic business,” human beings could never move out of central Africa.
No one moved out of Africa having to have the folks backhome baying the bils. Think more resent colonies.
> You’re assuming everything would be transported from Earth, ==
They’ll use the cheapest source, and do your own cutting edge tech invoves huge capital and personal expences. NATIONScan’t pull that off now, so I a small colony – especially starting up – couldn’t do it at even higher costs.
>>> What exactly do jet fighters have to do with space colonies? I
>>> thought we were talking about building bases in space, not jet fighters.
>> No, we were talking about what part of the current market for space activities a Colony could successfully compete for.
> No, the idea that current markets are the only markets that will ever exist is your hangup.
We weren’t talking about ever – we were talking about waht market could start up a colony.
> I suggested that military bases could evolve into space colonies.==
Actually you didn’t say that, you said the military fraction of current expenditures in space. – but skiping over that, it misses the point since you wouldn’t need a space mil base until AFTER there weer economically self supporting colony. So saying a colony could be founded on the economics of supporting a mil base is kind of backwards.
> == why yammer about jet fighters?
You brought it up – seemed pretty off topic to me.
>>> You’re talking about military space as it exists today, ==
>> Yes, we were talking about the current space market, or any
>> near term market, that could form a economic bassis for a space colony.
> There’s a big difference between “near term” and “what exists today.” =
You started talking about current expenditures in space, and how that money poured into a space colony….
You have another funding source, happy to talk about it.
>>> That won’t last forever. Space will be militarized no matter what pacifists wish.
>> True – once theres enough there to be worth fighting for.
> Some people think America is worth fighting for. “Whoever controls
> space controls the Earth.”
That argument came up in the 60’s that we should build a missile base on the moon to stop the red menace. There are easier ways to defend Earth then with a space colony. Actually I can’t think how you could use a space colony of any types to defend the US etc from any enemy.
>== Why do you think China is developing a military spaceplane? ==
Never heard them eve claiming they were. They are sticking with Soyuz knockoffs for the next 20 years or so – and they “MIGHT” get people to the moon in the 2020’s
>> Higher from lunar or Asteroid material. Check out the DOE
>> report in the ’70’s comparing SSPS built exclusivly from
>> Earth launched prefabracated parts vrs the Lunar>L-5 senerio.
> The DOE never even looked at extraterrestrial resources. Most of
> the study didn’t even concern engineering. ==
Didn’t need to – the base economicof Exter terestrial resources was based on high launch costs being 90+% of the cost of a Earth launch concept. But unlike O’Neil they actually contacted the big aerospace firms to propose launch systems and project costs in a SSPS project, adn it came out over a order of magnitude cheaper then the O’neil proposal – which invalidated their basic cost structure completly — as well as dramatically simplifying the program.
>> Far higher capital costs to develop and field thelunarmines,
>> launch facilities, in space caters, smelting/milling/manufacturing facilities.
You want to build a colony in space – like on Earth they have to pay their way. Handwaving about things in the distent future might be different – only say you abandoned any hope of near term space colonization.
Delta-V isn’t a cost driver even now in Earth launch. Earth launch to LEO costs pennies per pound of energy to LEO. So cutting that by a factor of 20 doesn’t help you. (A nit that a lot of space advocates overlook.) Longer term it means les since power will be cvheaper and we’ll use better drives.
I haven’t personally done the math, but I understand that the energy cost of common propellants for Earth to Orbit is on the order of five thousand pennies ($50) per pound. That’s a hard floor on chemical propulsion to orbit. Something like the space elevator would have energy costs on the order of $5 per pound perhaps plus a bit to lift propellant for station keeping on the far end.
Current airlines indicate that fuel costs are about a third of overall costs. So it’s reasonable to assume that even a space launch infrastructure on the scale of the commercial airlines is going to have a floor of around $150 per pound.
Now its possible some other economic factor could make lunar ore more desirable. Better ore, legal flexibility, cheaper ships or something. But all that’s kind of far future industrial trade offs.
I think it’ll be simply comparative advantage. Sure Earth could provide all the materials, but the Moon would be there, with plenty of solar energy, a lower gravity well, vacuum, and a need to trade. Meanwhile, the payload that Earth saves on crude materials would then be used for more valuable payloads like people, electronics, manufactured goods, etc.
A key problem is the cost of energy on the Moon. There would be a very loose coupling in that if energy cost on the Moon is too high, then it becomes cheaper to import it (for example, as nuclear reactor fuel) from Earth. That would work the other way as well (exporting either beamed power or some other product like nuclear fuel or Helium 3).
My view is that the constraint for Lunar power will be the amount of lunar labor required to produce solar cells. I figure it’ll start at least an order of magnitude more than a skilled Earth-side teleoperator. This means a strong incentive for automation beyond anything we’ve seen on Earth. If near complete automation of solar cell production and deployment can be done, then that enables lunar launch infrastructure.
For example, you could then have magnetic rail to escape velocity (or beyond) plus some crude propulsion system dependent solely on Lunar materials (say a LOX/aluminum hybrid motor) to provide the remaining delta v needed to reach a desired destination.
> Karl Hallowell Says:
> October 17th, 2009 at 8:15 am
> I haven’t personally done the math, but I understand that the
> energy cost of common propellants for Earth to Orbit is on
> the order of five thousand pennies ($50) per pound.
> That’s a hard floor on chemical propulsion to orbit. Something
> like the space elevator would have energy costs on the order
> of $5 per pound perhaps plus a bit to lift propellant for station keeping on the far end.===
The fuel costs (not energy) vari with craft design, but for a full rocket SSTO (biggest fuel hog config) with LOx/Kerosene rockets, its $8 per pound of cargo to LEO. With normal overhead for craft (most vehicles in a mature market cost about 3 times uel costs) your at $24 a hour. Course if you use air-breathing propulsion systems you can cut that in half. For comparison Air frieght over similar energy distances would be about $4/pound.
Space elevators actually are very expensive. Advocates overlook the extremely high capital costs the cables for a Earth to orbit space elevator would easily be $200 billion, for a cable capable of carrying 2000 tons a year. So it comes to about $500 a pound assuming a couple decade service life before the cables degrade from exposure.
>> Now its possible some other economic factor could make lunar
>> ore more desirable. Better ore, legal flexibility, cheaper ships or
>> something. But all that’s kind of far future industrial trade offs.
> I think it’ll be simply comparative advantage. Sure Earth could provide
> all the materials, but the Moon would be there, with plenty of solar
> energy, a lower gravity well, vacuum, and a need to trade. ==
Again – its the economic factors. Everyone wants to trade, and will try to undercut each others prices. Earth has a hell of a lot of folks eager to sell you not just ore – but refined manufactured parts. Since their capital costs were likely already absorbed before you placed your order – you get your product at margin costs + profit. From the moon you have not only high capital costs. You have higher operating costs since your on the moon – which is not likely going to be a cheep place to operate in the forseeable future.
>== Meanwhile, the payload that Earth saves on crude materials would
> then be used for more valuable payloads like people, electronics, manufactured goods, etc.
You have it backwards. the more payload you lift, the lower the cost per pound for all.
> A key problem is the cost of energy on the Moon. There would be a very
> loose coupling in that if energy cost on the Moon is too high, then it
> becomes cheaper to import it (for example, as nuclear reactor fuel)
> from Earth. That would work the other way as well (exporting either
> beamed power or some other product like nuclear fuel or Helium 3).
Helium 3 is kind of a space advocate myth. No reactors are being designed to use HE3 adn their are Earth based sources. The same low radiation fuel effect can be gained using Boron-11, which costs about $0.05/pound. Solar power tends to be very pricy – which again hurts your bottom line.
> My view is that the constraint for Lunar power will be the amount
> of lunar labor required to produce solar cells. I figure it’ll start at
> least an order of magnitude more than a skilled Earth-side teleoperator.
> This means a strong incentive for automation beyond anything
> we’ve seen on Earth. ==
Problem is its almost totaly automated on Earth already.
Solar cells costs can run to most of a $1000 a pound, and given any significant space colony effort would drive launch costs down a lot lower then that (well under $100 a pound if you seriously going to build a biuld a colony), so the production costs dominate. So pricer production costs on your “remote facility” could lock you out of the market.
The fuel costs (not energy) vari with craft design, but for a full rocket SSTO (biggest fuel hog config) with LOx/Kerosene rockets, its $8 per pound of cargo to LEO. With normal overhead for craft (most vehicles in a mature market cost about 3 times uel costs) your at $24 a hour. Course if you use air-breathing propulsion systems you can cut that in half. For comparison Air frieght over similar energy distances would be about $4/pound.
Very interesting, this is much cheaper than the LOX/LH2 propellant. Let’s suppose your vehicle is made of perfect, massless unobtainium so that the only mass in the system is the propellant and the payload. Glancing around, it appears that the best possible ISP for LOX/kerosene is 300-353 seconds (that corresponds to an exhaust velocity of 2940-3,460 m/s) depending on atmospheric pressure. Further let’s suppose that you need only to reach 9,500 m/s in order to achieve LEO. That means that you have a mass fraction of roughly 4.0-6.4%, all purely payload. Another google indicates that the oxidizer to fuel ratio (in mass, if I understand correctly) is ideal somewhere around 2.5. I gather not very pure LOX is cheaper than dirt, cents per pound. And I get a price something like $0.40 per pound for kerosene. That yields a propellant price of somewhere around $0.20 per pound. Toss in a multiplier of 16-25, and you get a fuel price of $3 to $5 per pound of payload. I don’t know what the mass of Kelly’s SSTO adds, sounds like it’s consumes around half the available payload.
You have it backwards. the more payload you lift, the lower the cost per pound for all.
I didn’t say anything about lifting less payload to space. I’m talking about substituting more valuable payload (eg, electronics) for less valuable payload (concrete mix, structural members, bulk LOX).
> Karl Hallowell Says:
> October 17th, 2009 at 2:54 pm
>> The fuel costs (not energy) vari with craft design, but for a
>> full rocket SSTO (biggest fuel hog config) with LOx/Kerosene
>> rockets, its $8 per pound of cargo to LEO. With normal overhead
>> for craft (most vehicles in a mature market cost about 3 times
>> fuel costs) your at $24 a pound. Course if you use air-breathing
>> propulsion systems you can cut that in half. For comparison Air
>> frieght over similar energy distances would be about $4/pound.
> Very interesting, this is much cheaper than the LOX/LH2 propellant. ==
Very. LH is much lighter (though it makes a much heaver ship) so you could more then halve the weight of fuel – but the fuel costs over 3 times as much per pound.
>== Let’s suppose your vehicle is made of perfect, massless
> unobtainium so that the only mass in the system is the
> propellant and the payload. Glancing around, it appears that
> the best possible ISP for LOX/kerosene is 300-353 seconds —
You can get up to 365 isp in vacum , sea level tends down toward 300. Another reason to augment with airbreathers(like a ramjet shroud) to really increase ISp lower.
You might want to check actual isp for rockets on the ,market – or used to be.
http://www.astronautix.com/props/loxosene.htm
>== (that corresponds to an exhaust velocity of 2940-3,460
> m/s) depending on atmospheric pressure.
> Further let’s suppose that you need only to reach 9,500 m/s
> in order to achieve LEO. ==
Youre delta-V is a bit high at 9500. Also LOx/Kero boosters consume a higher fraction of their mas low, adn are more streamlined, so the delta-v to orbit is lower still. Figure 7600-8000 delta-V.
>= That means that you have a mass fraction of roughly 4.0-6.4%,
> all purely payload.
Total none fuel mass for a LOx/Kero SSTO is about 8.3% Course in a real ship your cargo will be about 2%.
>== Another google indicates that the oxidizer to fuel ratio
> (in mass, if I understand correctly) is ideal somewhere around 2.5.
Depends on the engine. RD-180s are one of the best currently on the market http://www.astronautix.com/engines/rd180.htm#RD-180 its ration is 2.72.
> I gather not very pure LOX is cheaper than dirt, cents per pound.
I large quantity about $0.05 a pound.
>= And I get a price something like $0.40 per pound for kerosene. ==
About.
>> You have it backwards. the more payload you lift, the lower the cost per pound for all.
> I didn’t say anything about lifting less payload to space.
Oh sorry.
>I’m talking about substituting more valuable payload (eg, electronics)
> for less valuable payload (concrete mix, structural members, bulk LOX).
Why? Fly more often. Another launcher in the fleets a lot cheaper then a lunar mine. Unless you have a huge long term sustained demand for your lunar ore (probably millions or tens of million, of tons a year) I don’t think you save money.
You need to cave $’s not Lb’s.
😉
No you just keep changing the def of terms when the numbers don’t add up. You can’t define what would be a base market to start or build a colony on.
Rubbish. I listed several markets. You just ignore them and play nonsense word games, like claiming NASA doesn’t spend any money on science because you have your own private definition of “science.”
> It’s pretty obvious that human spaceflight is a substantial market, ==
really, based on what? At what price point?
Based on the fact that NASA and RSA spend billions of dollars on it every year, at current price points. No, don’t bother giving me some Kelly Stark definition that says what they do “isn’t spaceflight.” I’ve had enough word games.
> You’re assuming everything would be transported from Earth, ==
They’ll use the cheapest source, and do your own cutting edge tech invoves huge capital and personal expences. NATIONScan’t pull that off now, so I a small colony – especially starting up – couldn’t do it at even higher costs.
We don’t need “cutting edge tech.” We could have “pulled it off” decades ago. We decided not to, for a variety of reasons.
> No, the idea that current markets are the only markets that will ever exist is your hangup.
We weren’t talking about ever – we were talking about waht market could start up a colony.
Yes, and that apparently upset you. So, you went off on rants about how science isn’t science and the military won’t be allowed to construct colonies in space because national security doesn’t allow jet fighters to be built outside the US.
I’m still waiting for you to explain why you thing space colonies are jet fighters.
Actually you didn’t say that, you said the military fraction of current expenditures in space. – but skiping over that, it misses the point since you wouldn’t need a space mil base until AFTER there weer economically self supporting colony.
False. If you had read books like “Confrontation in Space,” you would know that. We need bases in space to protect economic assets right here on Earth. If we don’t build them, someone else will.
Actually I can’t think how you could use a space colony of any types to defend the US etc from any enemy.
Yes, that is obvious. I’ve recommended books that can help you understand. If you refuse to read them, there’s nothing I can do about that.
>== Why do you think China is developing a military spaceplane? ==
Never heard them eve claiming they were. They are sticking with Soyuz knockoffs for the next 20 years or so – and they “MIGHT” get people to the moon in the 2020’s
No, that is just the public show for the peanut gallery. Go look at the pictures of Divine Dragon.
Didn’t need to – the base economicof Exter terestrial resources was based on high launch costs being 90+% of the cost of a Earth launch concept. But unlike O’Neil they actually contacted the big aerospace firms to propose launch systems and project costs in a SSPS project, adn it came out over a order of magnitude cheaper then the O’neil proposal
No, they didn’t. I have copies of those studies right on my shelves. You obviously don’t. They never did any studies of extraterrestrial resources or claimed any of the things you say they did.
> Kelly Starks Says:
>> No you just keep changing the def of terms when the numbers
>> don’t add up. You can’t define what would be a base market to start or build a colony on.
>== like claiming NASA doesn’t spend any money on science because
> you have your own private definition of “science.”
Or because its not spent on science – in any event tyhey certainly wouldn’t spend it at your colony.
>>> It’s pretty obvious that human spaceflight is a substantial market, ==
>> really, based on what? At what price point?
> Based on the fact that NASA and RSA spend billions of dollars
> on it every year, at current price points. ==
They don’t spend billions on launch or flight. Hell, little of the shuttle budget goes to the shuttle. most goes to care and feed kSC/JSC/etc
> No, don’t bother giving me some Kelly Stark definition that says
> what they do “isn’t spaceflight.” I’ve had enough word games.
And you’re assuming you can take over ever dime listed to a space program even though little if any could possibly be done in a space colony. Much less that they would spend it at your colony.
>>> You’re assuming everything would be transported from Earth, ==
>> They’ll use the cheapest source, and do your own cutting edge tech
>> invoves huge capital and personal expences. NATIONScan’t pull that
>> off now, so I a small colony – especially starting up – couldn’t do it at even higher costs.
> We don’t need “cutting edge tech.” We could have “pulled it off” decades ago. We decided not to, for a variety of reasons.
>>> No, the idea that current markets are the only markets that will ever exist is your hangup.
>> We weren’t talking about ever – we were talking about waht market could start up a colony.
> Yes, and that apparently upset you. ==
No, though your going off on military bases in space definatly takes it out of the near term start of category. So I not unreasonably was wondering what you consider can be a start up economic basis for a colony.
==
>== If you had read books like “Confrontation in Space,” you would
> know that. We need bases in space to protect economic assets right
> here on Earth. If we don’t build them, someone else will.
Oh please! Thats like saying we need a mil base in Manhatten to defed it. That logic got thrown out decades ago.
==
>>>== Why do you think China is developing a military spaceplane? ==
>> Never heard them eve claiming they were. They are sticking with
>>Soyuz knockoffs for the next 20 years or so – and they “MIGHT”
>> get people to the moon in the 2020’s
> No, that is just the public show for the peanut gallery. Go look at the pictures of Divine Dragon.
Go look at pictures of NASP, skylon, USAF missle bases on the moon, etc. Slideshows are not plans.
>> Didn’t need to – the base economicof Exter terestrial resources was
>> based on high launch costs being 90+% of the cost of a Earth launch
>> concept. But unlike O’Neil they actually contacted the big aerospace
>> firms to propose launch systems and project costs in a SSPS project,
>> adn it came out over a order of magnitude cheaper then the O’neil proposal
> No, they didn’t. I have copies of those studies right on my shelves.
>You obviously don’t.
No mines on my hard drive.
> They never did any studies of extraterrestrial resources or claimed
> any of the things you say they did.
I was referring to O’Neil’s studies of ET material. The basic economics were based on the assumed extremely high Earth launch costs – and the assumed extremely low lunar launch costs. Thoses assumptions were invalid, and they were the complete basis of the L-5 colony economic basis.
Ok Ed,
Tryingtoget this back from a bunch of debates over what each said when. A point list of actual points weer talking about.
What could be the economic basis for a colony.
You know as well as I do that just because NASA has a budget lineitem saying $6 billion a year for the shuttle program – that doesn’t mean they spend $6 billion a year launching shuttles. If they budget $100 billion for a launcher dev program – at least 3/4th are unnessisary funds federal programs must spend havingnothing to do with getting the ships built. Basic federal contracting.
Also, if they spend $x billion on launch services – none of that can be taken over by a space colony – since by def its alread IN space, so it can’t carry something TO space.
As for building or doing something in space. There are a lot of political reasons why gov would rather not use someones colony (its more important the money get spent in the right political districts, then that they get the best product or cheaest price. Etc), and economic and practical reasons why its cheaper or more effective to build and launch stuff from Earth in any near term project, then harvesting space resources and building them.
These are all pretty much straight forward and obvious issues. So how do you get around them and find a market of billions of dollars a year (at least) – that could support and justify a space colony?
Tourism? You could fit a decent Disneyland in one of these – but could you expect millions of visitors a year to support it? Whatlaunch systems would need to be developed adn how – to lower costs enough?
Manufacturing? What would make economic sence at curentprice points?
Minning? How do you economically deliver it – or product made with it, to Earths Markets? (No, building things in space for space doesn’t help.
Who would/could put up that kind of capital to start it? The old O’Neil L-5 colony, SSPS industry concept never raised the money – and likely never made economic sence given the mistakes related to launch costs.
So where does this leave us if we want to build these?
Youre delta-V is a bit high at 9500. Also LOx/Kero boosters consume a higher fraction of their mas low, adn are more streamlined, so the delta-v to orbit is lower still. Figure 7600-8000 delta-V.
You ignore gravity losses. And you can’t accelerate too fast in atmosphere. I intended 9500 m/s as a somewhat low estimate of the delta v required.
Why? Fly more often. Another launcher in the fleets a lot cheaper then a lunar mine. Unless you have a huge long term sustained demand for your lunar ore (probably millions or tens of million, of tons a year) I don’t think you save money.
That seems rather high. But sure, by that point the Moon has something to offer.
>> Karl Hallowell Says:
>> October 19th, 2009 at 10:16 am
>> Youre delta-V is a bit high at 9500. Also LOx/Kero boosters
>> consume a higher fraction of their mas low, adn are more streamlined,
>> so the delta-v to orbit is lower still. Figure 7600-8000 delta-V.
> You ignore gravity losses. ==
No thats including grav loses – thats why I mentioned LOx/Kero consumes a bigger fraction of its mass low. If you burn it up low, you don’t need to lift it against gravity as long or far.
>==And you can’t accelerate too fast in atmosphere. ==
Wasn’t suggesting it – though some ships are designed to to save LOx. Mach 6 and 150,000 feet say.
>> Why? Fly more often. Another launcher in the fleets a lot cheaper
>> then a lunar mine. Unless you have a huge long term sustained
>>demand for your lunar ore (probably millions or tens of million, of
>> tons a year) I don’t think you save money.
> That seems rather high. But sure, by that point the Moon has something to offer.
Its like starting a factory in a foreghn country. If you only sell – say a few hundred, or a few thousand cars in the region, that doesn’t justify the new factory in a new hard to support place. Sell millions and you have a reason.
😉
I’m sorry, but I don’t see it. I see 7,400 m/s instantaneous delta v required to get to LEO (7,800 m/s bare minimum minus 400 m/s from Earth’s rotation at 28.5 latitude). From here (which is citing this book, there are a range of delta v for selected US rockets from the 70’s and 80’s. To summarize, gravity losses range between 1,200 and 1,600 m/s of delta v and atmospheric losses start at 50 m/s (for the slowest starter and go up to around 150 m/s for the Titan IV which has an aggressive acceleration rate. Collectively the best have delta v around 1300 m/s (Delta 7925, a Delta II variant and Shuttle). You might need some extra to circularize the orbit.
While 8,600+ m/s is a lot less than I was thinking. I still don’t see how you’re getting 7,600 to 8,000 m/s. I think the trade off between gravity losses and the effects of air resistance (both losses to friction and the resulting loading on the vehicle) will keep you from getting much more than that. That at least seems to be the conventional wisdom in the stuff I read.
>.. I still don’t see how you’re getting 7,600 to 8,000 m/s…
Those weer numbers from Micheal Burnside-Clapp paper on it.
Though given the shuttle lists about 9000 to get to the ISS, and I think 8000 ish to a normal LEO orbit, the number didn’t surprize me much.
Ok, I’ve found the original paper. It was posted in the sci.space.policy USENET group. I have to say that it is incomplete and doesn’t address my concerns. He doesn’t take into account air resistance or loading on the vehicle.
Well air resistence would obviously be a lot less given the denser fuel would allow a ship with only a fraction of the frountal area, but for a verticle assent ship boosting out of the air pretty quick I would think raising less mass to altitude would be a bigger help?
Well air resistence would obviously be a lot less given the denser fuel would allow a ship with only a fraction of the frountal area, but for a verticle assent ship boosting out of the air pretty quick I would think raising less mass to altitude would be a bigger help?
Not if you’re moving much faster through atmosphere when you’re in it. I just find it hard to believe that the US and USSR didn’t figure out this advantage of denser propellant. Maybe when they tried, they lost rockets due to the additional strain of atmospheric loading (say ripping fins off or causing structural failure somewhere between nose cone and engine).
> Not if you’re moving much faster through atmosphere when you’re in it. =
Your not necessarily. You’ld still be as heavy right after launch, and likely accelerate about as fast given the same thrust to weight ratio. By the time your disproportionately lighter, the air would be very thin. At 75,000 feet for example air density is 1/100th that on the surface. But thats only 15 miles up. Under a tenth your orbital height. Now later your booster could accelerate you faster as the power to weight ratio gets much better then a LOx/LH booster – but by then there isn’t any real atmosphere to give you drag..
>== I just find it hard to believe that the US and USSR didn’t
> figure out this advantage of denser propellant. ==
Oddly a lot of things weren’t realized, or have been forgotten.
When McDonnel Douglas did studies for the DC-X SSTO, they also ran the numbers for a Kerosene LOx version and reportedly weer surprized to find it was much easier to build a SSTO shuttle with Kerosene fuel then LH. The LH version allowed a high % of the vehicle at take off to be the vehicle – but the LH vehicle had to be disproportinastly heavy with a huge hydrogen take.
A weirder recent example is NASA folks and the Augustine panel disregarding the possibility of reusable space ships adn assembling huge craft in orbit launched in multiple parts. Yet the Shuttles been reusable for 30 years, assembled the huge ISS in multiple launches, adn cost a small fraction of the cost of Ares/Orion to develop or operate. Its like FedEx or UPS execs insisting overnigh delivery of packages is impossible.
I’m still not satisfied on the air resistance problem, but this paper has been out for more than ten years. So let’s suppose you are right. Is there an even denser fuel choice that would work better than LOX/Kerosene? Let’s ignore for the moment really exotic choices (like something involving fluorine).
For an extreme example, white fuming nitric acid (WFNA) and furfuryl alcohol (a propellant combination that apparently has been used before), are both rather dense. WFNA has according to Wikipedia, a density of a bit over 1.5 g per cubic cm and furfuryl alcohol a density of somewhere around 1.128 g per cubic cm. I’m not sure where that puts the fuel mix, but it’s probably well over 1.2. In comparison, LOX/Kerosene is slightly more dense than water (1.031 g per cubic cm) and LOX/LH2 has a collective density of around 0.358 g per cubic cm.
>==
>Is there an even denser fuel choice that would work better than
>LOX/Kerosene? Let’s ignore for the moment really exotic choices
>(like something involving fluorine). ==[ white fuming nitric acid (WFNA) and furfuryl alcohol ]
There are, but they are pricy, and tend to disolve things – like the ships, fueling techs, etc.
Also theres not a big dif. I think Kero is about 8-9 times as dense as LH (so you roughly triple the density – according to your numbers), and easy to store and handel with normal materials. As apposed to 20% more then that with WFNA, but you might need to go to heavier stainless steel tanks adn plumbing or such.
> ==
> For an extreme example, white fuming nitric acid (WFNA)
> and furfuryl alcohol === it’s probably well over 1.2. In comparison,
> LOX/Kerosene is slightly more dense than water (1.031 g per cubic cm)
> and LOX/LH2 has a collective density of around 0.358 g per cubic cm.