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#21
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Sedna, space probes?, colonies? what's next?
Dez Akin wrote:
"Mike Combs" wrote in message ... "Marvin" wrote in message ... You are advocating *SOLAR* power, out that far? snip You dont need large mirrors, you need un-be-fooking-lievably giganic hugenourmous mudderfookahs of mirrors. All very true. But in 0-G, the mirrors needn't be anything more substantial than aluminized mylar stretched over bailing wire. Gerard O'Neill got curious how far a space habitat could range from the sun simply by increasing mirror size. He decided a good stopping point was when the mirror came to mass as much as the rest of the habitat. The calculation came out as 10x the distance of Pluto. I just read that Sedna is currently about 3x the distance of Pluto (yes, I know, it gets out a lot farther). Theres nothing wrong with nuclear. By the time we start considering space habitats this far out, nuclear fusion might even be viable, but we can build molten salt fission plants now for fueling a huge colony for at least a couple of centuries. Yes, but you can't build a huge colony even in Earth or Moon orbit - never mind somewhere far away - nor move it as things stand. And the cause for that is launch costs, something that is not noticably helped by nuclear reactors. -- Sander +++ Out of cheese error +++ |
#22
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Sedna, space probes?, colonies? what's next?
"Sander Vesik" wrote in message ... Uddo Graaf wrote: "TKalbfus" wrote in message ... I find it interesting that Sedna was discovered near its closest point in its 10,500 year orbit around the Sun. What are the chances of that happening? If you only consider the planet Sedna, the chances of discovering it while it is near is closest point to the Sun are very small. Sedna spends most of its time further away, this leads to the question how many other "Sedna's" are there? What if we looked for a 10th planet 1000 years ago with the same technology we have today? Would we find another Sedna-like planet nearing its closest point to the sun. Sedna will spend 150 closer to the Sun than from where we discovered it. statistically this leaves room for about 60 planets in 10,000 year orbits around the sun. all those planets are potential colonies for future colonists. The ones further away will be harder to find, but I'm sure we can eventually discover them. Colonies that far away from the Sun? Unlikely. Mankind can multiply like rabbits and it would still take at least 300 years to fill up the inner planets and moons. Sedna or its denizen's aren't likely candidates for colonization and when they are, mankind will probably have developed FTL (faster than light) propulsion and reach for planets beyond our solar system. Even with FTL, colonising Oort cloud may be easier than plants around far-away stars. At 4c it still takes 9months for a one-way trip to Alpha Cenaturi - and much longer for other stars. FTL - unless it is high multiples of lightspeed - only makes interstellar travel and colonisation slightly easier. You will pobably still need generation ships - just the number of generations born on-ship will be lower. Mostly colonization will be done by 'system hopping' and will therefore be doable. Someone calculated once that if we started now, we could colonize the entire Galaxy in 3000 years. |
#23
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Sedna, space probes?, colonies? what's next?
John Savard wrote:
On Wed, 17 Mar 2004 16:50:48 +0100, "Uddo Graaf" wrote, in part: Colonies that far away from the Sun? Unlikely. Mankind can multiply like rabbits and it would still take at least 300 years to fill up the inner planets and moons. Earth is already full, and not more than the tiniest fraction of its Debatable. Stick copies of biosphere II all over the world, and you end up with well over 10 times the population. |
#24
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Sedna, space probes?, colonies? what's next?
"Ian Stirling" wrote ...
Debatable. Stick copies of biosphere II all over the world, and you end up with well over 10 times the population. Better hope they work a bit better than the first biosphere II then. ;-) |
#25
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Sedna, space probes?, colonies? what's next?
On Thu, 18 Mar 2004 13:34:35 GMT, in a place far, far away,
lid (John Savard) made the phosphor on my monitor glow in such a way as to indicate that: On Wed, 17 Mar 2004 16:50:48 +0100, "Uddo Graaf" wrote, in part: Colonies that far away from the Sun? Unlikely. Mankind can multiply like rabbits and it would still take at least 300 years to fill up the inner planets and moons. Earth is already full, and not more than the tiniest fraction of its people can be launched into space. Both of those statements are blatantly false. |
#26
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Sedna, space probes?, colonies? what's next?
volatiles - from which biological material is constructed - not in a
deep gravity well, such as is found on the gas giants. It is true that there are also Io and Europa, for example, but radiation may be a problem with them, or other concerns, even aesthetic ones, may be operable. What is so nonaesthetic about the Jupiter system? It's not Saturn, but if (big if) you could live on I&E without being cooked, Jupiter's proximity might be the penultimate travel-photo op in Sol system |
#27
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Sedna, space probes?, colonies? what's next?
Earth is certainly too crowded for solar power to
be sufficient here. Hardly. 71% of it has no human life at all. We could *float* the solar collectors. Places such as North Africa are good dry-land alternatives, though there are political barriers there. If Earth is not to become a pre-techological subsistence park, it will *have* to be solar one day. |
#28
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Sedna, space probes?, colonies? what's next?
Ian Stirling wrote: John Savard wrote: On Wed, 17 Mar 2004 16:50:48 +0100, "Uddo Graaf" wrote, in part: Colonies that far away from the Sun? Unlikely. Mankind can multiply like rabbits and it would still take at least 300 years to fill up the inner planets and moons. Earth is already full, and not more than the tiniest fraction of its Debatable. Stick copies of biosphere II all over the world, and you end up with well over 10 times the population. How much did Biosphere II cost, per inhabitant? |
#29
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Sedna, space probes?, colonies? what's next?
On Thu, 18 Mar 2004 18:00:20 GMT, in a place far, far away, Dick
Morris made the phosphor on my monitor glow in such a way as to indicate that: Debatable. Stick copies of biosphere II all over the world, and you end up with well over 10 times the population. How much did Biosphere II cost, per inhabitant? A lot, but you can't conclude anything from that, since there were no economies of scale. |
#30
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Sedna, space probes?, colonies? what's next?
"Sander Vesik" wrote in message
... I think there is a slight difference between 'can be done' and 'makes sense to do' - Oh, total agreement here. I was only trying to make the point that whatever other objections might be raised, an inability to use solar power needn't be one of them. Personally, I can't see a reason for anybody to want to live at 10x the distance of Pluto... unless they REALLY hate people. given the distance, does it even make sense as a space based source of ice/water? There are surely lots of others between here and there. -- Regards, Mike Combs ---------------------------------------------------------------------- We should ask, critically and with appeal to the numbers, whether the best site for a growing advancing industrial society is Earth, the Moon, Mars, some other planet, or somewhere else entirely. Surprisingly, the answer will be inescapable - the best site is "somewhere else entirely." Gerard O'Neill - "The High Frontier" |
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