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#22
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Greg Neill wrote:
Until quite recently in our history the average age for starting a new generation was about 16. You started there and kept at it until you or the missus dropped dead of old age at about 35 (Well, disease actually; bodies wore out pretty quickly from malnutrition and constant battles with disease). A significant fraction of mortality in women came during childbirth (or just thereafter). Or so I've heard. Brian Tung The Astronomy Corner at http://astro.isi.edu/ Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/ The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/ My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt |
#23
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#24
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Tim Auton wrote in message:
snip then. 25 years is, very roughly, a generation. I thought as much. So 50,000/25 = 2000. I stand duly corrected, the 2,000th generation will eventually get greeted by the warm sunshine from Alpha Centauri! With an initial crew make-up of just 900 people, they will have "inbred" hundreds of times over that expected for natural conditions on Earth, right? And there'll be all diseased and weak, etc when they arrive at New Earth... There is a way around this: you can take frozen eggs and sperm from a much wider gene pool on reserve from Earth; the Centauri Princess' (name of the starship) computer monitors births and deaths along the voyage for each person/family. It calculates roughly after how many natural births one needs to expand one's gene pool. The ship's medical team then advise their passengers *when* they should start drawing on the frozen fertility ingredients... So there is a solution (assuming frozen genetic material can keep for 50,000 years of course!) One question: when the 50,000th year party celebrations are to be thrown on the ship right at the end... what would you call that? It's not the 50,000th "centenary"? A new word is needed in the future spaceflight dictionary... Abdul |
#25
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"AA Institute" wrote in message om... Tim Auton wrote in message: snip then. 25 years is, very roughly, a generation. A few hundred years ago, it was common for the woman to get pregnant and then get married, just to check there were no problems. This might have been in the late teens and typical family size was roughly 5 to 10 children with two year gaps. Mean age of the parents at birth was around 22. Then social attitudes changed and being born "out of wedlock" was the worst thing possible. Better health care meant fewer infant deaths and high living standards meant less dependence on your children in old age so family size tended to fall. A later start but fewer children meant a slight rise in average age of the parents. Currently, there is a problem. In many countries the average family is less than 2.4 children, which is not even sustainable, and couples are waiting until their thirties so that they have their careers established before taking a break for a family. You need to consider how attitudes and lifestyle will be affected to work out the average age, and of course over so many generations, there will be many changes. I thought as much. So 50,000/25 = 2000. I stand duly corrected, the 2,000th generation will eventually get greeted by the warm sunshine from Alpha Centauri! With an initial crew make-up of just 900 people, they will have "inbred" hundreds of times over that expected for natural conditions on Earth, right? And there'll be all diseased and weak, etc when they arrive at New Earth... They would probably be producing children so deformed that they would be sterile, or even be dieing before puberty, within a few dozen generations. There is a way around this: you can take frozen eggs and sperm from a much wider gene pool on reserve from Earth; the Centauri Princess' (name of the starship) computer monitors births and deaths along the voyage for each person/family. It calculates roughly after how many natural births one needs to expand one's gene pool. The ship's medical team then advise their passengers *when* they should start drawing on the frozen fertility ingredients... So there is a solution (assuming frozen genetic material can keep for 50,000 years of course!) The couples involved would ignore that advice completely because they want to have _their_ children, not someone else's. The first generation or two might stick to it because they started the voyage knowing what was needed. After that, why should kids stick to rules made by their great-great-grandparents? They have the right to choose, etc. If a couple does ignore the advice, what could be done? Enforced abortion followed by enforced artificial insemination? I don't think so. Then again, who would enforce it? If that was done to one couple, would they then apply those rules to their children and grand- children? It seems highly unlikely and remember the problems don't show up until several generations later. The solution is to have a population the size of "Babylon 5". You should also consider that a population the size you propose wouldn't have enough people to have a league in most sports and couldn't support much of an entertainment industry. It's going to be a very boring place. The majority are going to be simple farmers, what else is there to do? One question: when the 50,000th year party celebrations are to be thrown on the ship right at the end... what would you call that? It's not the 50,000th "centenary"? A new word is needed in the future spaceflight dictionary... 50000th anniversary 500th centenary or centennial 50th millennium There may be new words in their vocabulary though. Consider what we call the time 50000 years ago: Lower Paleolithic -- (the oldest part of the Paleolithic Age with the emergence of the hand ax; ended about 120,000 years ago) Middle Paleolithic -- (the time period of Neanderthal man; ended about 35,000 years BC) Upper Paleolithic -- (the time period during which only modern Homo sapiens was known to have existed; ended about 10,000 years BC) What arrives in your story will have evolved to be quite different to the humans that get there by faster (unmanned) means and spent 45000 years exploring and adapting to an alien planet. George |
#26
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"AA Institute" wrote in message om... snip One question: when the 50,000th year party celebrations are to be thrown on the ship right at the end... what would you call that? It's not the 50,000th "centenary"? A new word is needed in the future spaceflight dictionary... Abdul It would be the 5,000th centenary, since centenary means something that occurs every 100 years. |
#27
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"Laura" wrote in message ... "AA Institute" wrote in message om... snip One question: when the 50,000th year party celebrations are to be thrown on the ship right at the end... what would you call that? It's not the 50,000th "centenary"? A new word is needed in the future spaceflight dictionary... Abdul It would be the 5,000th centenary, since centenary means something that occurs every 100 years. Oops... too quick for my own good :-) 500th, of course. |
#28
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"George Dishman" wrote:
snip ... I wonder if cosmic rays can make objects of certain chemical composition "glow in the dark"? So the ship might pass through a zone of glowing gas or icy meteoroids acting as substitute for shooting stars on Earth! http://www-ssg.sr.unh.edu/tof/Outrea...nterdepth.html 75% hydrogen, 25% helium, both transparent, at about 1 atom per cc, and a tiny amount of fine, black dust. Although the density is very low, you may still need to consider drag over such a long voyage. Very interesting. "Our sun (and solar system) are currently moving through a cloud of interstellar gas." - quote from the above article. As far as I know, the so-called "Pioneer effect" was never satisfactorily resolved and I think both probes were retarded by microscopic amounts in their solar system escape trajectories out towards interstellar space. Do you suspect the interstellar winds/medium could have had a part to play in this? Thanks AA |
#29
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"George Dishman" wrote:
snip snip You should also consider that a population the size you propose wouldn't have enough people to have a league in most sports and couldn't support much of an entertainment industry. It's going to be a very boring place. The majority are going to be simple farmers, what else is there to do? My story shows never a dull moment. Mining comets, shopping, boating trips along the river in the sky, taking shuttles out on starship fly arounds, 360-degree night sky views (24 hour astronomy!), having the freedom of job rotations, as well as catching up on all the local gossip and mischief that's part of being who we are... There was even going to be a "Miss Centauri Princess" competition... which I've had to cut short due to time pressure... There'll be sports facilities onboard too. No, it's a "miniature Earth" alright albeit in a fantasy land... What arrives in your story will have evolved to be quite different to the humans that get there by faster (unmanned) means and spent 45000 years exploring and adapting to an alien planet. These *faster* means of interstellar travel are still equally in the realm of theoretical spaceflight, otherwise we would have launched a few unmanned flights by now... It's all in the future. |
#30
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"Laura" wrote:
Oops... too quick for my own good :-) 500th, of course. Thank you Laura. Very well, "500th Centenary Celebrations" it shall be! Abdul |
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