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O'Neill colony's and generation ships 
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Post O'Neill colony's and generation ships
I hope I didn't doubled some topic.

I looked through Insider files of Terran six worlds. How they were settled? I know that Mars was inhabited before FTL was invented (it's a guess). Do the one or more extrasolar colonys was "conquered" by a generation ship? Were some incidents along the road (like wait calculation or mutiny). Maybe some generation ships are still traveling the void?

For reference: http://www.projectrho.com/public_html/rocket/slowerlight.php

Second question is for O'Neill or artificial gravity colonys floating in space. Do they exist. It's logical for Umiak to inhabit a space station/colony in planet's orbit and command automatons/ geneticly enginered drones on ground to mine ore and cultivate crops.

Do Terrans use space colonys?


Fri Dec 28, 2012 3:27 am
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Post Re: O'Neill colony's and generation ships
Mali wrote:
I hope I didn't doubled some topic.

I looked through Insider files of Terran six worlds. How they were settled? I know that Mars was inhabited before FTL was invented (it's a guess). Do the one or more extrasolar colonys was "conquered" by a generation ship? Were some incidents along the road (like wait calculation or mutiny). Maybe some generation ships are still traveling the void?


I think all the extrasolar colonies were founded after FTL was invented. Generation ships by definition require generations to reach their targets, and judging from the year the story takes place - 2160 C.E., there simply wasn't time for that.

I'd assume that once you have the jump drive, you send out scout ships, determine which star systems are valuable (habitable planets, useful and easily accessible resources, chiefly fuel for your starships), do proper observations and measuring of things like the velocity of the stars' relative movements to calculate safe jump routes, and then send out 'colony ships' to establish basic infrastructure. Civilians will then probably be encouraged to take over as the main investor in the colony. Governments will probably provide tax and/or trade incentives to motivate people to move to the colonies.


Fri Dec 28, 2012 4:09 am
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Post Re: O'Neill colony's and generation ships
Victor_D wrote:
Mali wrote:
I hope I didn't doubled some topic.

I looked through Insider files of Terran six worlds. How they were settled? I know that Mars was inhabited before FTL was invented (it's a guess). Do the one or more extrasolar colonys was "conquered" by a generation ship? Were some incidents along the road (like wait calculation or mutiny). Maybe some generation ships are still traveling the void?


I think all the extrasolar colonies were founded after FTL was invented. Generation ships by definition require generations to reach their targets, and judging from the year the story takes place - 2160 C.E., there simply wasn't time for that.

I'd assume that once you have the jump drive, you send out scout ships, determine which star systems are valuable (habitable planets, useful and easily accessible resources, chiefly fuel for your starships), do proper observations and measuring of things like the velocity of the stars' relative movements to calculate safe jump routes, and then send out 'colony ships' to establish basic infrastructure. Civilians will then probably be encouraged to take over as the main investor in the colony. Governments will probably provide tax and/or trade incentives to motivate people to move to the colonies.


What you wrote is a "Wait Calculation" problem. Tau Ceti is 12 light years from Earth. If we get a drive with 0.1 light year/per year speed it could be 120-240 years to get there. So no generation ship there. But Alpha Centauri is 4.3, so with the same drive it's 43-86 years of flight (i'm doubling max. years cuase this all acceleration/braking shananigans). But if we have 0.5 drive, colony ship could get to Tau Ceti 24-48 years. To Alpha Centauri it could be 8.6 - 17.2 (someone got to check my numbers - I'm archaeology major and I think I made some mistakes along the road). Then comes time changes. On ship going with 0.99 speed of light one year is 7 years outside. So going somewhere may be 400 years travel that crew experiances as 20 years (this is an example, not real math).
Now the mentioned "Wait Calculation" kicks in. It's a theory if it's acceptable to sent colonists on a long ride with knowing that some day FTL will be invented. If so, then how far generation ship's can go before FTL ships could out run them? There's also Lem's view (aren't polish scfi writers the great?) that faster travelers could just pick up slower ones along the road and help them get quicker to destination. But that probably don't work in Outsider FTL, that's locks on gravity well of a star system.

I heard somewhere that closed comunitys on Earth like amish or hutterites could be the first ones to settle high frontier because they have high population growth and are hard working types, always looking for new land to colonize. Only flaw of this theory - they don't like high tech, that is needed for space colonization. It would be funny if Aldea was colonized by Amish and the capital was New Lancaster. :)


Fri Dec 28, 2012 11:21 am
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Post Re: O'Neill colony's and generation ships
Mars colonization began around 2050, prior to the development of jump drive. There were no attempts at slower-than-light interstellar travel prior to the development of jump drive, but even if there had been, you can't just send a colony ship to a star system without scouting it first. Even the scouts would have been overtaken by FTL vessels before they ever reached their destinations.

Space habitats will be common, ranging from small space stations to large Gundam style "Side" habitats. I think the larger habitats will be most common where a work force is required far away from convenient ground-based habitats, such as at large industrial complexes/shipyards out at Lagrange points. But it's also true that the Umiak will favor such habitats over ground housing on heavy gravity worlds.

Mali wrote:
I heard somewhere that closed comunitys on Earth like amish or hutterites could be the first ones to settle high frontier because they have high population growth and are hard working types, always looking for new land to colonize. Only flaw of this theory - they don't like high tech, that is needed for space colonization. It would be funny if Aldea was colonized by Amish and the capital was New Lancaster.

I would certainly expect that fringe groups that are unhappy with Earth culture or restrictions would be among those most interested in moving to the colonies. However, interstellar transport is expensive, especially in the early days of colonization, and so such groups would need substantial economic clout.

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Fri Dec 28, 2012 12:23 pm
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Post Re: O'Neill colony's and generation ships
Mali wrote:
What you wrote is a "Wait Calculation" problem. Tau Ceti is 12 light years from Earth. If we get a drive with 0.1 light year/per year speed it could be 120-240 years to get there. So no generation ship there. But Alpha Centauri is 4.3, so with the same drive it's 43-86 years of flight (i'm doubling max. years cuase this all acceleration/braking shananigans). But if we have 0.5 drive, colony ship could get to Tau Ceti 24-48 years. To Alpha Centauri it could be 8.6 - 17.2 (someone got to check my numbers - I'm archaeology major and I think I made some mistakes along the road). Then comes time changes. On ship going with 0.99 speed of light one year is 7 years outside. So going somewhere may be 400 years travel that crew experiances as 20 years (this is an example, not real math).
Now the mentioned "Wait Calculation" kicks in. It's a theory if it's acceptable to sent colonists on a long ride with knowing that some day FTL will be invented. If so, then how far generation ship's can go before FTL ships could out run them? There's also Lem's view (aren't polish scfi writers the great?) that faster travelers could just pick up slower ones along the road and help them get quicker to destination. But that probably don't work in Outsider FTL, that's locks on gravity well of a star system.


Well, about the travel speeds. I think it is not even remotely realistic we will be able to build any crewed starships going faster than a few percent of light speed by the end of the century. Chemical and fission nuclear-thermal rockets are out of question, since they can't get you anywhere in some reasonable time, even for generation ships. The first propulsion system that could get us to the stars would be nuclear fusion. We're still (some evil people claim permanently) 30 years away from mastering even the simplest D+T fusion for commercial purposes. Even if we somehow managed to develop a fusion drive by the end of this century (say 2090), it wouldn't make a ship go faster than 0.1 c and even that is probably well beyond what's practical for fusion rockets. At that speed reaching Alpha Centauri would take about 45 years, which is within a natural human lifespan, but you'd still arrive just a few decades before the start of the Outsider main story.

Going faster with large crewed ships would require propulsion systems so difficult to develop that I just don't see it happening in this century no matter what we do.

Arioch wrote:
Mars colonization began around 2050, prior to the development of jump drive. There were no attempts at slower-than-light interstellar travel prior to the development of jump drive, but even if there had been, you can't just send a colony ship to a star system without scouting it first. Even the scouts would have been overtaken by FTL vessels before they ever reached their destinations.


Speaking of FTL - how come humans developed it so quickly? Was it more or less an accidental discovery (at least the main theoretical principle which makes it possible, I'd assume the development of a practical working prototype itself was expensive and long, not to mention extremely dangerous), or were the humans actively pursuing ideas for FTL interstellar travel all along?

Also, I think sending an unmanned probe first would basically be enough. If the probe is compact and light enough, you can make it travel much faster than the actual crewed ship.

(I still think generation ships are a terrible idea though, since they're so impractical in terms of the weight you're carrying. Some sort of hibernation/cryogenic suspension for the crew is bare minimum if we want to settle the stars that way, in my opinion.)


Fri Dec 28, 2012 2:31 pm
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Post Re: O'Neill colony's and generation ships
Victor_D wrote:
Speaking of FTL - how come humans developed it so quickly? Was it more or less an accidental discovery (at least the main theoretical principle which makes it possible, I'd assume the development of a practical working prototype itself was expensive and long, not to mention extremely dangerous), or were the humans actively pursuing ideas for FTL interstellar travel all along?

Also, I think sending an unmanned probe first would basically be enough. If the probe is compact and light enough, you can make it travel much faster than the actual crewed ship.

If hyperspace exists, I would expect its existence to be predicted by theory and confirmed by experiment long before Humanity has the technology to make a workable drive. The discovery probably happened in the 2030's or 2040's, but it was not until the last few decades of the 21st Century that humans developed the gravity control technology required to build a working jump drive.

I would certainly expect that the prototype jump vessels were unmanned.

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Post Re: O'Neill colony's and generation ships
i can see it

In 2030 humanity launch is first generation ship to alpha Alpha centauri (just saying that cause that the first thing i thought, don't kill me for being inaccurate in the possibility of an extra solar colony)
*150 year later*
-Captain, we are getting some radio signal from the planet!!!
-On screen!
*an earth colonist answer*
-hey welcome to this 15 year old colony!


Fri Dec 28, 2012 9:40 pm
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Post Re: O'Neill colony's and generation ships
Mali wrote:
What you wrote is a "Wait Calculation" problem. [snip]

Now the mentioned "Wait Calculation" kicks in. It's a theory if it's acceptable to sent colonists on a long ride with knowing that some day FTL will be invented. If so, then how far generation ship's can go before FTL ships could out run them? There's also Lem's view (aren't polish scfi writers the great?) that faster travelers could just pick up slower ones along the road and help them get quicker to destination. But that probably don't work in Outsider FTL, that's locks on gravity well of a star system.
Certainly Lem's suggestion wouldn't work for Outsider FTL, but with the other stereotypical types of FTL I assume that generation ships would actually themselves be destinations, rather than just being the guys that took the slow route. Unless you assume that FTL is easier with a larger vessel, any initial FTL ships would be small and short-ranged. That would make the generation ships the equivalent of an oasis in a desert for them.

So yeah, once FTL was developed in a setting with any-point to any-point FTL, the technology would quickly make it's way to any generation ships that were sent out. However, this would be more because the FTL ships used the generation ships as staging points, than any other reason.

Mali wrote:
I heard somewhere that closed comunitys on Earth like amish or hutterites could be the first ones to settle high frontier because they have high population growth and are hard working types, always looking for new land to colonize. Only flaw of this theory - they don't like high tech, that is needed for space colonization. It would be funny if Aldea was colonized by Amish and the capital was New Lancaster. :)
The Amish/Mennonites/Hutterites follow a rule something along the lines of "no unneeded technology", or something like that. Some are stricter, others more relaxed. Among the Amish and Mennonites, apparently most of the rules are decided by the community, not religious in nature (the side-effects are the focus of concern), vary even between neighboring communities, and are largely decided on the basis of whether it will cause ties to be broken with neighboring communities (where they get spouses from).

Of the bunch of them, I suspect that Hutterites would be both the most open to the idea (as I understand it, their focus is less on "no technology", and more on "community"), and the most likely to succeed (and, in fact, Hutterites might be better suited than most human societies to space colonies) since they pool their wealth, work as a group, and are already familiar with years-long large scale projects to establish new communities. The Amish and Mennonites I would suspect to be less likely to be interested than your average American, since they would likely see it as unnecessary as long as land was available. I don't think that any of them would be likely to try to go extra-solar though.

Victor_D wrote:
The first propulsion system that could get us to the stars would be nuclear fusion.
Depends on the scale desired. The book Roche World suggests a solar sail craft, with an associated laser array in Mercury's orbit to provide it with a brighter light source. But it only suggests it for a small crew. This doesn't help with the Outsider timeline, of course.

Victor_D wrote:
We're still (some evil people claim permanently) 30 years away from mastering even the simplest D+T fusion for commercial purposes.
You might want to check into the Polywell. It seems to be doing pretty good, since the Navy keeps funding it.

Victor_D wrote:
Going faster with large crewed ships would require propulsion systems so difficult to develop that I just don't see it happening in this century no matter what we do.
Agreed. This is a high-energy problem.

Victor_D wrote:
Also, I think sending an unmanned probe first would basically be enough. If the probe is compact and light enough, you can make it travel much faster than the actual crewed ship.
Yes. In Roche World they sent a crewed vessel several stars away (it wasn't one of the Centauri triplets, though it was somewhere comparatively close), and the author apparently did his math, so I'd expect at least that technique to work pretty well for probes.

Victor_D wrote:
(I still think generation ships are a terrible idea though, since they're so impractical in terms of the weight you're carrying. Some sort of hibernation/cryogenic suspension for the crew is bare minimum if we want to settle the stars that way, in my opinion.)
I don't think that hibernation would work much better. What you really want if you're planning to get somewhere quick is essentially a short-cut, such as a wormhole. Even with FTL, if you're having to spend the energy to get close to the speed of light then it's likely to be too expensive for "colony" scale usage. If you can't get FTL or a shortcut then you're going to be taking forever anyways.


Fri Dec 28, 2012 10:44 pm
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Post Re: O'Neill colony's and generation ships
Absalom wrote:
Depends on the scale desired. The book Roche World suggests a solar sail craft, with an associated laser array in Mercury's orbit to provide it with a brighter light source. But it only suggests it for a small crew. This doesn't help with the Outsider timeline, of course.


Laser sails require a) huge diameter, b) insanely powerful lasers, and you're still pushing only a very small craft (like in Rocheworld). Since these lasers could just as well be targeted at Earth to melt the territory of an unfriendly nation state, I'd advise against this method of propulsion on the principle of abusability ;) (Maybe if you built them on the Lunar far side so that they could never be used against Earth...)

Solar sail is only practical within the solar system, and won't provide the acceleration we need to travel to the stars in reasonable times.

Quote:
You might want to check into the Polywell. It seems to be doing pretty good, since the Navy keeps funding it.


With a meagre sum, and it's all classified anyway. Maybe there is something there, I doubt it. In any case, for the purpose of space propulsion, you need either inertial confinement fusion or a 'leaky' magnetic confinement reactor. We have neither working on Earth, and we're decades away from both. Designing an actual propulsion system for the purposes of interstellar travel would be FAR more daunting a task.

Quote:
Agreed. This is a high-energy problem.


*Insanely* high energy problem ;)

Quote:
Yes. In Roche World they sent a crewed vessel several stars away (it wasn't one of the Centauri triplets, though it was somewhere comparatively close), and the author apparently did his math, so I'd expect at least that technique to work pretty well for probes.


Rocheworld was written by Robert Forward, possibly the best author of hard sci-fi. Read Dragon's Egg if you haven't yet.

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I don't think that hibernation would work much better. What you really want if you're planning to get somewhere quick is essentially a short-cut, such as a wormhole. Even with FTL, if you're having to spend the energy to get close to the speed of light then it's likely to be too expensive for "colony" scale usage. If you can't get FTL or a shortcut then you're going to be taking forever anyways.


Meh, this is too speculative. I was speaking of what we actually might do, as opposed what we can do in sci-fi ;) I know that hibernation is actually pursued by the European Space Agency (there is research going on with some promising results), and in the future cryogenic suspension may become practical. This would of course help a lot since the amount of ship mass dedicated to life support could be greatly shrunk. I *think* that if we build interstellar ships one day (centuries from now), they'll be very flimsy, tethery, and light so that they can achieve relativistic speeds.


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Post Re: O'Neill colony's and generation ships
Victor_D wrote:
Quote:
You might want to check into the Polywell. It seems to be doing pretty good, since the Navy keeps funding it.


With a meagre sum, and it's all classified anyway. Maybe there is something there, I doubt it.
It looks like they're still testing small-scale models, so I'm not all that daunted by it. At any rate, it's basically just a revolution in an already proven design, so if they can sufficiently eliminate the energy losses of the Fusor without adding too many of their own, it'll produce net power.

Victor_D wrote:
Quote:
I don't think that hibernation would work much better. What you really want if you're planning to get somewhere quick is essentially a short-cut, such as a wormhole. Even with FTL, if you're having to spend the energy to get close to the speed of light then it's likely to be too expensive for "colony" scale usage. If you can't get FTL or a shortcut then you're going to be taking forever anyways.


Meh, this is too speculative. I was speaking of what we actually might do, as opposed what we can do in sci-fi ;) I know that hibernation is actually pursued by the European Space Agency (there is research going on with some promising results), and in the future cryogenic suspension may become practical. This would of course help a lot since the amount of ship mass dedicated to life support could be greatly shrunk. I *think* that if we build interstellar ships one day (centuries from now), they'll be very flimsy, tethery, and light so that they can achieve relativistic speeds.
Honestly, if I were in charge of some far-future space program, I wouldn't try to colonize star systems much further that Alpha/Beta Centauri unless I actually had some sort of "shortcut" technology, or mass-elimination technology. I don't consider it realistic to try to create an entire colony by sending a large population to other stars at a meaningful fraction of the speed of light, just too high-energy. This is the sort of thing where I'd send some universal assemblers, a biological & technological "STC" (ala WH40k), and presumably some trained bootstrapping specialists. Though this is assuming that we haven't gone down the road of "upload" in this far-future scenario.

As for hibernation technology, we'll be seeing it in ambulances sometime soon, as well as in operating rooms. They've nailed down two or three mechanisms, and various quirks, and already demonstrated the technology on dogs (in fact, they drained the blood out of a dog for a few minutes, put it back in, and the dog was seemingly fine afterwards). Sub-freezing cryogenic technology is more of an issue, but with time we'll develop the needed bio-compatible anti-freezes.

Regardless, relativistic ships will want to be low-mass ships, and "several thousand people, with attendant cooling, life-support, and related consumables" is only low-mass in comparison to the alternative.


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Post Re: O'Neill colony's and generation ships
Absalom wrote:
It looks like they're still testing small-scale models, so I'm not all that daunted by it. At any rate, it's basically just a revolution in an already proven design, so if they can sufficiently eliminate the energy losses of the Fusor without adding too many of their own, it'll produce net power.


As I say, we'll see. I don't know enough to make a serious prediction, I am just naturally sceptical (specifically, I doubt this will scale up well).

Absalom wrote:
Honestly, if I were in charge of some far-future space program, I wouldn't try to colonize star systems much further that Alpha/Beta Centauri unless I actually had some sort of "shortcut" technology, or mass-elimination technology.


Minor nitpick: both the stars are called Alpha Centauri, it's the name of the whole system. The primary star is A, the secondary orange one is B. Jury is still out whether Proxima is gravitationally bound to Alpha Centauri.

The problem with all these shortcuts and mass effects ( ;) ) and antigravity and whatnot is that they're essentially magic. If our understanding of physics is mostly correct, then they're impossible, or theoretically possible if impossible materials existed (matter with negative energy density/negative mass, commonly referred to as "unobtainium" or "handwavium" ).

In short, don't hold your breath.

Quote:
I don't consider it realistic to try to create an entire colony by sending a large population to other stars at a meaningful fraction of the speed of light, just too high-energy. This is the sort of thing where I'd send some universal assemblers, a biological & technological "STC" (ala WH40k), and presumably some trained bootstrapping specialists. Though this is assuming that we haven't gone down the road of "upload" in this far-future scenario.


Define large. I can see as possible sending a few thousands, perhaps tens of thousands of people on sublight ships travelling at some meaningful speed (say 0.3 c) to a planet we know is habitable from telescope/probe observations (yes, extrasolar planets can be imaged if you use big enough telescopes. Well, a group of them flying in formation, using interferometry to cancel out the stars light). The colony would for all intents and purposes be totally independent and completely self-sufficient; the only thing exported/imported would be information beamed to/back from Sol.

Quote:
As for hibernation technology, we'll be seeing it in ambulances sometime soon, as well as in operating rooms. They've nailed down two or three mechanisms, and various quirks, and already demonstrated the technology on dogs (in fact, they drained the blood out of a dog for a few minutes, put it back in, and the dog was seemingly fine afterwards). Sub-freezing cryogenic technology is more of an issue, but with time we'll develop the needed bio-compatible anti-freezes.


Hopefully. It remains to be seen if human brain can be "re-started" after deep freeze without consequences to our consciousness. Simpler hibernation (as in "winter sleep") would be useful here in our Solar system, especially for long missions to the outer planets, which will initially last many years.

Quote:
Regardless, relativistic ships will want to be low-mass ships, and "several thousand people, with attendant cooling, life-support, and related consumables" is only low-mass in comparison to the alternative.


Yes, but you can't go much lower if you still want to send actual people. You can do it Arthur C. Clarke's way - send robot ships with human embryos - but I'd advise against that. We want to colonize to ensure the long term survival of our species AND our culture. Culture is transmitted from generation to generation, implying the old generation should be there to interact with the new.

I don't want to think much about what is possible in all these post-human/trans-human settings, that's just not attractive enough to me :)


Sun Dec 30, 2012 1:43 am
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Post Re: O'Neill colony's and generation ships
Victor_D wrote:
Absalom wrote:
Honestly, if I were in charge of some far-future space program, I wouldn't try to colonize star systems much further that Alpha/Beta Centauri unless I actually had some sort of "shortcut" technology, or mass-elimination technology.

Minor nitpick: both the stars are called Alpha Centauri, it's the name of the whole system. The primary star is A, the secondary orange one is B. Jury is still out whether Proxima is gravitationally bound to Alpha Centauri.

Right. To elaborate further, Beta Centauri is a B1 III blue-white giant (thought to be a spectroscopic binary) some 350 light years away, and not associated in any way with Alpha Centauri (except for being in the same region of the sky as viewed from Earth).

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Post Re: O'Neill colony's and generation ships
And in astronomical terms, it won't be around much longer. It already is a giant star.

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Post Re: O'Neill colony's and generation ships
If we could get at least 0.1 of speed of light, then the worlds in 10 light years radius could be colonized after a one or two generations long ride (100 years - i'm not counting for accelerating and slowing, wich would probably make the trip longer). A ship need to have a colonist crew at least 50 (wich would be enough for genetic safty for few generations) or 500 (indefenitly safe from genetic issues). Some postulate even 2000 people, while some think that 160-180 would be good.

That much said, if by Outsider's 2040s theory was done (even before humans could stand on Mars), it's a good guess that all generation/hibernation long range sub light colony ships ideas or projects were scraped.

I think that getting offhomeworld for humans is as expensive as getting tickets to Australia for Eurpeans. You must work half a year and cover expenses (room in closed space colonys isn't probably cheap).

I like the idea of generation ship standing as a oasis for small range FTL crafts - i think that Tau in WH40K do something like this.

If every spacefaring race in Outsider verse have gravity control (needed for FTL), than it means no O'Neill colonys... Sad. No Gundum for this reader...


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Post Re: O'Neill colony's and generation ships
Victor_D wrote:
Absalom wrote:
It looks like they're still testing small-scale models, so I'm not all that daunted by it. At any rate, it's basically just a revolution in an already proven design, so if they can sufficiently eliminate the energy losses of the Fusor without adding too many of their own, it'll produce net power.


As I say, we'll see. I don't know enough to make a serious prediction, I am just naturally sceptical (specifically, I doubt this will scale up well).
That actually looks like the only thing that it's viability depends on.

Victor_D wrote:
The problem with all these shortcuts and mass effects ( ;) ) and antigravity and whatnot is that they're essentially magic. If our understanding of physics is mostly correct, then they're impossible, or theoretically possible if impossible materials existed (matter with negative energy density/negative mass, commonly referred to as "unobtainium" or "handwavium" ).

In short, don't hold your breath.
I actually ran myself through a thought-experiment once, to figure out how distance-alteration would probably work. It goes like this:
Assume that you have a cable long enough that it's ends can experience enough cosmic-inflation induced velocity in relation to each other that you could theoretically measure it if you had a device to do it, but not so long that the force would be enough to snap the cable. Connect a large mass to one end of the cable. Then place another mass at the half-way point of the cable, connected not to the cable, but instead to a generator. The generator, of course, is configured to produce electricity if the cable moves. Finally, you place two similar masses close to the ones connected to the cable, but without an actual connection to much of anything, and another cable parrallel to the first, and of the same length: these form your control samples.

There are two possible outcomes: either the cable moves relative to the generator, thereby producing electricity, or it doesn't. If you configured the experiment correctly (meaning, in such a way that you can conclusively eliminate causes other than spatial inflation), then you get a close to definitive answer to whether or not it's possible to modify distances. The key question is basically this: is it possible to use the inflation of the universe as an energy source, or not? The implication being that if yes, then energy should be usable to both increase and decrease inflation, and by extrapolation to alter the physical distances between two things.

I assume that actually doing the experiment would require a location outside of the galaxy, which would render the attempt sufficiently impossible. However, since this is something that would work on intergalactic plasma sheets as well, observations could possibly do the trick as well.

Of course, the interesting possibility is "the generator experienced no motion relative to the cable, but inflation was still observed". I suspect that the energy requirements even if the experiments produced positive results would be poor, though.

Victor_D wrote:
Quote:
I don't consider it realistic to try to create an entire colony by sending a large population to other stars at a meaningful fraction of the speed of light, just too high-energy. This is the sort of thing where I'd send some universal assemblers, a biological & technological "STC" (ala WH40k), and presumably some trained bootstrapping specialists. Though this is assuming that we haven't gone down the road of "upload" in this far-future scenario.


Define large.
I'd say 100, though I haven't done the math yet. Remember, this is a high-energy problem. At any rate, the minimum population figures that I've heard for a viably population is indeed in the 1000s range, but if we cross our fingers and eyes we can assume that artificial gestation technology has been developed by this point, which would allow a relatively small starting population (let's say 50) to raise a much larger population (let's say 200, but you could realistically go quite a bit higher: the older children help to raise the younger children). If you can keep this going for a little while (which shouldn't be difficult at all if you're going to mount one of these missions in the first place) then the second on-site generation could easily be 800 (once again, going higher isn't hard), and the third can be 3200. And since all of these generations have been popped out of your artificial wombs according to "factory specs", they're likely to all have different genetics. The "natural born" individuals just add to the count.

As long as you send some specialists with sufficient boot-strapping technology, you shouldn't even need to send a viable population.

Victor_D wrote:
I can see as possible sending a few thousands, perhaps tens of thousands of people on sublight ships travelling at some meaningful speed (say 0.3 c) to a planet we know is habitable
[snip: something I already knew]
The colony would for all intents and purposes be totally independent and completely self-sufficient; the only thing exported/imported would be information beamed to/back from Sol.
Two caveats:
1) If you're focusing on already habitable planets, then you should probably cast your net wider. Just because a planet has the right atmospheric mix, or even the right pressure range, doesn't mean that it's habitable, the entire biosphere could be poisonous to you for all you know. Space habitats are seriously the right way to go, since you can make the environment as habitable as you want.
2) If you sent the expedition out properly equipped, then they won't even need info from Earth, though it certainly wouldn't be rejected. And if you're only focusing on already habitable planets, then you're very possibly too far away to get anything in the first place. Unless you seeded a trail of space habitats behind you to propagate the signal and maintain the transceivers, of course, in which case my point in the previous thread becomes dominant in your far-future civilization.

Victor_D wrote:
Quote:
As for hibernation technology, we'll be seeing it in ambulances sometime soon, as well as in operating rooms. They've nailed down two or three mechanisms, and various quirks, and already demonstrated the technology on dogs (in fact, they drained the blood out of a dog for a few minutes, put it back in, and the dog was seemingly fine afterwards). Sub-freezing cryogenic technology is more of an issue, but with time we'll develop the needed bio-compatible anti-freezes.


Hopefully. It remains to be seen if human brain can be "re-started" after deep freeze without consequences to our consciousness. Simpler hibernation (as in "winter sleep") would be useful here in our Solar system, especially for long missions to the outer planets, which will initially last many years.
Crewed outer-planet missions are far enough in the foreseeable future that I wouldn't want to do too much speculation on them. They aren't interstellar (even if you're going to Pluto), so we might launch them from somewhere further out than Earth for all we know (or we might use a pre-accelerated cycler of some sort). I certainly wouldn't argue against the many-years bit, but it doesn't have to be quite as bad as you might expect, as long as enough planning and money can be spent on it.

Victor_D wrote:
Quote:
Regardless, relativistic ships will want to be low-mass ships, and "several thousand people, with attendant cooling, life-support, and related consumables" is only low-mass in comparison to the alternative.


Yes, but you can't go much lower if you still want to send actual people. You can do it Arthur C. Clarke's way - send robot ships with human embryos - but I'd advise against that. We want to colonize to ensure the long term survival of our species AND our culture. Culture is transmitted from generation to generation, implying the old generation should be there to interact with the new.
Consider the likely time frame: several hundred years in the future. We're likely to have the technology to create the embryos from scratch at that point, which means that we just need to send the data and equipment. That's about as low-mass as we're likely to get the mission. If we add maybe 50 people then how much will we be sending? Surely much less than your version. That gives you the older generation and on-site trouble-shooters, at a presumably lower mass.

Victor_D wrote:
I don't want to think much about what is possible in all these post-human/trans-human settings, that's just not attractive enough to me :)
In many ways I agree, but I also wouldn't want to try it your way.

Mali wrote:
If we could get at least 0.1 of speed of light, then the worlds in 10 light years radius could be colonized after a one or two generations long ride (100 years - i'm not counting for accelerating and slowing, wich would probably make the trip longer). A ship need to have a colonist crew at least 50 (wich would be enough for genetic safty for few generations) or 500 (indefenitly safe from genetic issues). Some postulate even 2000 people, while some think that 160-180 would be good.
With a sufficient gene bank & associated systems, you shouldn't have to worry about genetic problems.

Mali wrote:
If every spacefaring race in Outsider verse have gravity control (needed for FTL), than it means no O'Neill colonys... Sad. No Gundum for this reader...
If Outsider gravity control provides "static" gravity then that might be the case, but if the gravity generators require constant power then I think that anything that can be made large enough will use an inertial system. It wouldn't surprise me if ships intended to operate in one location for a long period of time have their own retractable counterweight system, either.


Tue Jan 01, 2013 1:33 am
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