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# How Many People Does It Take To Colonize Another Star System?

#### Soulskill posted about 6 months ago | from the i'll-volunteer-everyone-in-california dept.

392

Hugh Pickens DOT Com writes: "The nearest star systems — such as our nearest neighbor, Proxima Centauri, which is 4.2 light-years from home — are so far away, reaching them would require a generational starship. Entire generations of people would be born, live, and die before the ship reached its destination. This brings up the question of how many people you need to send on a hypothetical interstellar mission to sustain sufficient genetic diversity. Anthropologist Cameron Smith has calculated how many people would be required to maintain genetic diversity and secure the success of the endeavor. William Gardner-O'Kearney helped Smith build the MATLAB simulations to calculate how many different scenarios would play out during interstellar travel and ran some simulations specially to show why the success of an interstellar mission depends crucially on the starting population size. Gardner-O'Kearny calculated each population's possible trajectory over 300 years, or 30 generations. Because there are a lot of random variables to consider, he calculated the trajectory of each population 10 times, then averaged the results.

A population of 150 people, proposed by John Moore in 2002, is not nearly high enough to maintain genetic variation. Over many generations, inbreeding leads to the loss of more than 80 percent of the original diversity found within the hypothetical gene. A population of 500 people would not be sufficient either, Smith says. "Five hundred people picked at random today from the human population would not probably represent all of human genetic diversity . . . If you're going to seed a planet for its entire future, you want to have as much genetic diversity as possible, because that diversity is your insurance policy for adaptation to new conditions." A starting population of 40,000 people maintains 100 percent of its variation, while the 10,000-person scenario stays relatively stable too. So, Smith concludes that a number between 10,000 and 40,000 is a pretty safe bet when it comes to preserving genetic variation. Luckily, tens of thousands of pioneers wouldn't have to be housed all in one starship. Spreading people out among multiple ships also spreads out the risk. Modular ships could dock together for trade and social gatherings, but travel separately so that disaster for one wouldn't spell disaster for all. 'With 10,000,' Smith says, 'you can set off with good amount of human genetic diversity, survive even a bad disease sweep, and arrive in numbers, perhaps, and diversity sufficient to make a good go at Humanity 2.0.'"

cancel ×

### Sure, but... (5, Insightful)

#### Joce640k (829181) | about 6 months ago | (#46663147)

By the time we have the tech to build a starship we can just ship out as many embryos as we can fit in a freezer. Job done.

### Re:Sure, but... (0)

#### bumba2014 (3564161) | about 6 months ago | (#46663237)

to be honest what is the use of this? Why do we want embryos on an other planet. Having to much people on earth won't be solved by sending embryos to other planet... As long as they can't send a large group of people in a short time to an other planet. This whole traveling to other planets is useless... And who says, we didn't already do this? Send out lots of ships to other planets. After that we got some water problems, like Noah's story. After that only a few people survived, started to multiply and created a new civilization. Those people we send out there, are now living happily. And yes, there comes a bunch of embryo's again....

### Re:Sure, but... (3, Insightful)

#### Jmc23 (2353706) | about 6 months ago | (#46663409)

Try and focus here, we're talking about the need for genetic diversity.

### Re:Sure, but... (1)

#### Anonymous Coward | about 6 months ago | (#46663413)

This story is about space exploration. "Too much people on Earth" has nothing to do with it and can be solved within 100 years with birth control if you really care.

### Re:Sure, but... (1)

#### Anonymous Coward | about 6 months ago | (#46663727)

personally I prefer famine, plague and war ... they're a lot more interesting than birth control to reduce populations to manageable levels and they work faster and are 100% effective; unlike most kinds of birth control and they aren't sins (war != murder ).

### Re:Sure, but... (4, Interesting)

#### lgw (121541) | about 6 months ago | (#46663445)

The point of exploring the stars will never be to "reduce the surplus population". That's not likely to be a real problem in any case.

The point is to broaden humanity's knowledge, perspective, and diversity. To make us, collectively, more than we are now.

But the stars are out of reach without some revolutionary new understanding of physics. The energy budget for interstellar travel is insane, assuming we want to get somewhere within a generation. It's far beyond workable fusion power needed for a starship: either some sort of warp drive, or antimatter fuel and a rocket with near-light speed exhaust.

The nice thing is, relativity means you can travel ridiculously long distances in subjective time and with an energy budget not much worse than going 100 light years. Humanity on Earth, not to mention the Sun, may be long gone when you get there, but you can visit other galaxies if only you had a magical power source.

### Re:Sure, but... (4, Interesting)

#### meta-monkey (321000) | about 6 months ago | (#46663643)

Reminds me of Tau Zero. [wikipedia.org] You can outlive the universe if you can squeeze yourself close enough to the speed of light...

### Re:Sure, but... (1)

#### lgw (121541) | about 6 months ago | (#46663717)

Hehe, they did more than outlive the universe. Awesome short novel.

### Re:Sure, but... (5, Interesting)

#### hawguy (1600213) | about 6 months ago | (#46663469)

to be honest what is the use of this? Why do we want embryos on an other planet. Having to much people on earth won't be solved by sending embryos to other planet... As long as they can't send a large group of people in a short time to an other planet. This whole traveling to other planets is useless...

Redundancy. Overpopulation is not the reason -- that's a self-correcting problem.

Having all of humanity stuck on a single planet in a single solar system leaves mankind open to extinction from a rare planet ending or even a more rare solar system ending event. Though we probably need to get out of the Galaxy for true redundancy. I don't think there's any way to avoid the eventual end of the universe, whether its ends in a big freeze or big crunch...But we have a bit of time before that happens, so it can be left for future generations, as long as we don't end up killing ourselves or depleting our resources before we can get off the planet.

And who says, we didn't already do this? Send out lots of ships to other planets. After that we got some water problems, like Noah's story. After that only a few people survived, started to multiply and created a new civilization. Those people we send out there, are now living happily. And yes, there comes a bunch of embryo's again....

I'm pretty sure the fossil record is complete enough to rule out modern humans suddenly popping up from seeded embryos.

### Battle Star Galactica... (0)

#### Anonymous Coward | about 6 months ago | (#46663645)

...had it right, enough people came to earth

### Useless? (1)

#### Shakrai (717556) | about 6 months ago | (#46663525)

This whole traveling to other planets is useless

You do know that Planet Earth has a finite future [wikipedia.org] , right?

### Re:Sure, but... (2)

#### JoeMerchant (803320) | about 6 months ago | (#46663539)

Having too many people on earth has historically proven solutions.

Generally, you hand out sharp and pointy objects, two or more colors of clothing, and let nature take its course....

### Re:Sure, but... (3, Interesting)

#### Arker (91948) | about 6 months ago | (#46663291)

"By the time we have the tech to build a starship we can just ship out as many embryos as we can fit in a freezer. Job done."

Not quite.

The 18 years we spend now may be excessive but even figuring adulthood at 15 those embryos do not just magically hatch out as viable colonists. So while this might be a reasonable side-project to help a little, it's far from "job done."

Another way to cut down on the requirements is to deliberately pick the colonists based on genetics rather than assume a 'random' sample. I am normally against any sort of pseudo-racial quota system on principle, but in this one narrow case it would have a direct and clear justification. If instead of assuming random participants, you assume participants deliberately picked to be as genetically distant from each other as possible, you should be able to reduce the population requirements quite significantly.

### Re:Sure, but... (2)

#### Joce640k (829181) | about 6 months ago | (#46663349)

If instead of assuming random participants, you assume participants deliberately picked to be as genetically distant from each other as possible, you should be able to reduce the population requirements quite significantly.

....and pack a whole load of extra embryos. Just to be sure.

### Re:Sure, but... (2)

#### nine-times (778537) | about 6 months ago | (#46663495)

I think the point was something more like, "We don't need to worry about genetic diversity if we can just pack embryos." That way, you can staff the spaceship with an appropriate number of people for making the trip and establishing a colony, and then use the embryos once you hit the point of needing genetic diversity.

Or pack eggs and sperm, mix as needed. Or just biological samples that can be cloned. Or hell, if we're getting really sci-fi here, maybe we can perform direct genetic manipulation by that point.

### Re:Sure, but... (2)

#### hawguy (1600213) | about 6 months ago | (#46663665)

"By the time we have the tech to build a starship we can just ship out as many embryos as we can fit in a freezer. Job done."

Not quite.

The 18 years we spend now may be excessive but even figuring adulthood at 15 those embryos do not just magically hatch out as viable colonists. So while this might be a reasonable side-project to help a little, it's far from "job done."

I would assume that they embryos would be inseminated and implanted into the human colonists, so people wouldn't have to follow a chart to decide who they can procreate with, all procreation comes from the stored embryos hand picked to ensure genetic diversity. Though I don't know how long embryos could be stored in a freezer.

Another way to cut down on the requirements is to deliberately pick the colonists based on genetics rather than assume a 'random' sample. I am normally against any sort of pseudo-racial quota system on principle, but in this one narrow case it would have a direct and clear justification. If instead of assuming random participants, you assume participants deliberately picked to be as genetically distant from each other as possible, you should be able to reduce the population requirements quite significantly.

How significantly? The frozen embryo plan seems to make the population more manageable -- They could keep a constant 100 (or 1000 or whatever) colonists on board for the first 250 years, then in the last 50 years or so, they can start implanting and growing the fetuses (or grow them in the baby-o-matic artificial uterus) to build up the population before landing. Or maybe just wait until after landing and an initial colony is built.

They'll need a lot of room for supplies and equipment so the fewer humans they have to keep alive during the journey, the more supplies they can bring.

### Re:Sure, but... (2)

#### Megahard (1053072) | about 6 months ago | (#46663293)

Already proposed by Kurt Vonnegut : The Big Space F*** [pierretristam.com]

### Re:Sure, but... (0)

#### Anonymous Coward | about 6 months ago | (#46663513)

Or use long term human hibernation. Or a cure for aging. Or mind uploads.

All of which are like rubbing two sticks together compared to the technological level of interstellar travel.

### Re:Sure, but... (0)

#### Anonymous Coward | about 6 months ago | (#46663535)

Not sure I'd want that. Frozen pizza is much tastier...

### Freeze the genetic material (2)

With technology, we can preserve a lot of genetic diversity in frozen embryos, eggs, sperm. So there are ways of mitigating the risk of genetic trait loss with a lower population.

### Re:Freeze the genetic material (2)

#### JoeMerchant (803320) | about 6 months ago | (#46663591)

What we really need is to bring a complete biosystem with us, enough species diversity to successfully colonize the planet with food producing plants that help maintain some semblence of stability in the O2 / CO2 levels and the temperature.

Or, we can just synthesize TV dinners from algae. Yum.

### Re:Freeze the genetic material (1)

I think JoeMerchant is on to something here. However...

Long story short, I don't see how we'll be able to move our whole solar system across the galaxy.

### Why send people? (4, Insightful)

#### bender647 (705126) | about 6 months ago | (#46663157)

How about a smaller sample of people and a large sperm and egg bank instead?

### Re:Why send people? (2)

#### reiserifick (2616539) | about 6 months ago | (#46663263)

Because raising 100 children per person at the same time sounds awfully like work

### Re:Why send people? (0, Funny)

#### Anonymous Coward | about 6 months ago | (#46663315)

How fascinating. Do you often read words that aren't actually there, or is this an isolated occurrence?

### Re:Why send people? (4, Insightful)

#### mi (197448) | about 6 months ago | (#46663403)

No need to raise them all at the same time. The discussion is not about people needed to get the colony going from the start — it is about preserving the genetic diversity over generations.

### Re:Why send people? (2)

#### mi (197448) | about 6 months ago | (#46663381)

large sperm and egg bank instead

I'm not sure, the female colonists — born and raised in space, BTW — will all agree to inseminate themselves with the thawed sperm of strangers instead of following the instinct to conceive in the hot embrace of their lovers.

Some of them might, but it is a risk, that the idea will be rejected en masse...

Perhaps, we'll develop incubators capable of replacing women's wombs — but even then there might be a problem with such kids being discriminated against in comparison with the "real" children...

It may be a solvable problem, but the solution will be complex.

### Re:Why send people? (1)

#### Your.Master (1088569) | about 6 months ago | (#46663483)

You don't have to send men at all in the first round. This gives at least until the colonist women dub the first generation of male children fuckable where if they're going to be pregnant, it's going to be embryos.

The other thing is, the entire sperm bank doesn't have to be spent in generation 1. With an inbreeding taboo and geneology, you could go several generations before you found yourself backed into a corner.

### Re:Why send people? (0)

#### Anonymous Coward | about 6 months ago | (#46663737)

If you can screen for sperm with X chromosones, you can ensure an all-female colony ship, ensuring no accidental babies.

### answered a long time ago (1, Troll)

#### dingleberrie (545813) | about 6 months ago | (#46663175)

According to a book I've read: Two of opposite gender (along with some other people from somewhere).

### Absurdly unnecessary (0, Troll)

#### Rigel47 (2991727) | about 6 months ago | (#46663187)

We're not far from being able to check-box for all the SNPs and phenotypes we want in offspring. The idea that we need to ship around tens of thousands of mouth-breathers just to maintain "diversity" is about as ludicrous as saying we'll need stout men to construct shelters upon arrival at the far side.

### Re:Absurdly unnecessary (-1)

#### Anonymous Coward | about 6 months ago | (#46663245)

Exactly, and those stout men will soon turn violent and recreate the Republican culture of rape we now have. We need to exclude their kind from any mission such as this.

### Re:Absurdly unnecessary (1)

#### Anonymous Coward | about 6 months ago | (#46663273)

Well that escalated quickly.

### Re:Absurdly unnecessary (1, Insightful)

#### Jmc23 (2353706) | about 6 months ago | (#46663449)

Unhappy thinkers with TMJ can never see the benefits of mouth-breathers.

Once you think you're smart enough to know what traits are desirable, nature will soon teach you how much of a dumb shit you are.

### Why send the people? (3, Interesting)

#### GameMaster (148118) | about 6 months ago | (#46663195)

If it's just genetic diversity you're worried about, why send the people themselves? It seems to me that sending that many people would be a massive over-expenditure of resources. Why not send much more manageable number of people to run the ship and build the initial settlement along with preserved genetic material for a massively larger population. Breed, predominantly, through artificial insemination for the initial generations until you are back to having the desired diversity in the actual living population.

### This Kind Of Hypothesizing Is Pointless (-1)

#### Anonymous Coward | about 6 months ago | (#46663217)

Unless we can figure out to control our population and planetary resource consumption, we're not going to get off the planet before we cannot get off the planet.

### Civilization 1 Got it Right! (0)

FP/FPE Combo!

#### NotDrWho (3543773) | about 6 months ago | (#46663227)

A lot of people (not us Slashdotters, of course) have the misconception that other solar systems are right next door to ours. So I always illustrate it like this: The fastest spacecrafts we've ever built take about 9 years or so to go from Earth to Pluto. At that rate, they would take about 120,000 years to reach the next closest solar system. I also saw a great illustration once using a quarter (coin), to represent our solar system, and the next solar system being something like two football fields away.

#### Jmc23 (2353706) | about 6 months ago | (#46663497)

Then they should move on to purpose.

What kind of engines do we put on weather balloons?

#### mi (197448) | about 6 months ago | (#46663515)

The fastest spacecrafts we've ever built take about 9 years or so to go from Earth to Pluto. At that rate, they would take about 120,000 years to reach the next closest solar system.

That's only because they spend most of this time without acceleration — in free fall. Once we find a way to continuously accelerate the ship even at the comfortable 1g, the 9 years shrinks to a couple of months (you accelerate for half the distance and then turn around and begin decelerating for the rest)...

#### stewsters (1406737) | about 6 months ago | (#46663599)

Its unlikely that they would send people like that, or that they would survive on a planet after adapting to 120,000 years worth of space travel.

They would construct a spacecraft that can accelerate at around 10 m/s^2 over hundreds of years, midway though the journey they flip it around and decelerate at the same pace. If the target planet is higher or lower gravity, they can ramp up or down acceleration to aclimant people to the change.

This way they are used to gravity and maintain a minimum time to arrive for the cargo carried. What kind of engine or power source would be necessary to do this is currently far beyond us, but may be possible one day.

They would also probably have to send robotic construction facilities ahead of the colonists to start building shelters. They will need to be able to harvest and construct additional robots and shelters without human intervention, as it is to far to remote control.

If we ever get the technology to do a full test-tube baby, perhaps we could freeze the genetic material and send it. Or possible chemically make it with our DNA stored as blueprints. We wouldn't actually 'travel', we would be generated on the planet. This is all high science fiction for now.

#### michelcolman (1208008) | about 6 months ago | (#46663639)

The fastest spacecraft we built never got anywhere close to light speed. If we can somehow figure out how to get to those speeds, the univers will shrink through Lorentz contraction and, in theory, it's perfectly possible to get to another galaxy in a few hundred years. Years measured on board, that is. Of course for earth many thousands (or millions) of years will have passed.

#### JoeMerchant (803320) | about 6 months ago | (#46663649)

Overblown, use a dime to represent our solar system and the next one will be less than 100m away....

Seriously, we "could" attempt to launch starships now, they'd take longer to reach the next star system than homo-sapiens has been present on earth, but it's not impossible....

More likely, we "should" be spending more time and energy on advancing our spacefaring tech, and perhaps a little less on all this other stuff that we do.

### Got it all wrong, way too high... (2)

#### MXB2001 (3023413) | about 6 months ago | (#46663235)

Just need 1. Clone said person over and over. Why assume that diversity is good? Do we really want to send reality TV loving cretins to colonize other planets?

### Re:Got it all wrong, way too high... (1, Funny)

#### Jmc23 (2353706) | about 6 months ago | (#46663517)

Yes, it might actually help to have people who are interested in social interactions.

### 1 is over kill but... (0)

#### Anonymous Coward | about 6 months ago | (#46663553)

If you want to preserve genetic diversity in a small population, just learn to genetically modify the gametes at will to produce the desired variance. And that is well within the possibilities of the current genetic engineering technology, a few years to refine the technology and make it safe for humans and we are good to go. Now, if we could simply put all the anti-science crowd in a nice and comfy padded room...

### On inbreeding (0)

#### Anonymous Coward | about 6 months ago | (#46663241)

Why not just allow for inbreeding and do continuous genetic testing on all embryos generated, terminating those that will turn into West Virginians?

### Re:On inbreeding (2)

#### sexconker (1179573) | about 6 months ago | (#46663531)

Why not just allow for inbreeding and do continuous genetic testing on all embryos generated, terminating those that will turn into West Virginians?

Why not just allow inbreeding? It's how we fucking colonized Earth. Genetic diversity isn't something to strive for, it's simply a result of a population surviving long enough in different circumstances (from diet to weather to disease). Absolutely none of the issues our current genetic diversity handles will be an issue for a colonization program. All people chosen will be screened appropriately so we'll know they're all decently healthy, and all potential catastrophic problems will be completely unlike those encountered (and survived) on Earth by humans before the advent of clothing, medicine, etc. The risk of inbreeding creating disfigured/disabled/impaired offspring is really quite low, especially if you screen for known issues in advance. It's a taboo with no basis in science. Yes, bad shit can happen when you start with bad genes, but that's just as likely as good shit happening when you start with good genes. Inbreeding is how all populations of sexual species bootstrap. When you get right down to it, ANYONE you marry is your cousin, and it doesn't fucking matter.

### using fake science history math religion etc... (-1)

#### Anonymous Coward | about 6 months ago | (#46663249)

no wonder we never get ahead of even the hymenless monkeys compassion wise http://www.youtube.com/results?search_query=wake+up+occupy

### Maintaining diversity is not the goal (4, Insightful)

#### HeckRuler (1369601) | about 6 months ago | (#46663265)

Five hundred people picked at random today from the human population would not probably represent all of human genetic diversity . . . If you're going to seed a planet for its entire future, you want to have as much genetic diversity as possible, because that diversity is your insurance policy for adaptation to new conditions

when it comes to preserving genetic variation

Except that's not the goal.
If you're talking about colonizing another star system (presumably this is way the fuck after we colonize mars, the moon, IO, Titan, Venus, Murcury, and whatever else we feel like) then little things like genetic diversity upon reaching the target are of little concern.

No, you care about GETTING THERE with enough wits about you that you can continue to function, and set up something to expand your capabilities.
The fight is not to keep the diversity we see on earth circa 2000, but rather the fight is against inbreeding from making everyone retarded to the point where they can no longer function.

Once you get there, and establish colonies, food supply, and your ecosphere can expand past the mothership, you can breed like rabbits and let nature take it's course to overcome whatever detrimental effects that being cooped up in a closed space for 30 generations might have had.

Or every generation could be a fucking clone while on the way there. Seriously, this is colonizing ANOTHER SOLAR SYSTEM. This is WAY OUT THERE. It's science fiction. Just what the hell were you planning of propelling this ship with for 30 years?

Hell, taking the long view, just spreading ANY form of sustainable life is a viable goal for this sort of project. At this scale, "humans" are transient things.

### Re:Maintaining diversity is not the goal (0)

#### Jmc23 (2353706) | about 6 months ago | (#46663561)

because wiping even half of the potential benefits that took nature millions of years to evolve and just thinking you can randomly generate them in an acceptable time span when you get there shows very little thinking ability.

about as much as my ability to use syntax.

### Re:Maintaining diversity is not the goal (1)

#### mi (197448) | about 6 months ago | (#46663567)

No, you care about GETTING THERE with enough wits about you that you can continue to function, and set up something to expand your capabilities.

If, as the write-up suggests, the "getting there" can be accomplished within only one or two generations, then much less genetic diversity is required to stay healthy and capable while in-transit.

The much larger diversity is needed for the colony to stay healthy in perpetuity. It is this post-transit diversity, that may require as many as 40000 people (or embryos).

### Chuck Shuck (1)

#### Tablizer (95088) | about 6 months ago | (#46663269)

I don't know, but bring woodchucks for giggles.

### Not needed just preferable (0)

#### Anonymous Coward | about 6 months ago | (#46663275)

They're not calculating the needed number of colonists, just the preferable number to maintain genetic diversity. But there are other ways to maintain diversity. Many thousands of frozen sperm, eggs, or embryos could be taken along. Colonist embryos could be analyzed and selected for diversity en route. Or diversity could be ignored and things would very likely turn out just fine, especially considering embryos with genes for disease could be replaced.

### its like I summoned him (0)

#### Anonymous Coward | about 6 months ago | (#46663277)

Bitched about Hasselton on the other article and Pickens shows up with something even more asinine.

### Re:its like I summoned him (0)

#### Anonymous Coward | about 6 months ago | (#46663361)

Normally I bitch about long-winded crap on the front page, but this is actually a news story and HPDC kept the summary shorter than anything Windbag Hasselton ever has. Plus, its definitely nerd fare and it's strictly rooted in science instead of politics.

### Space Fantasia 2001 Nights (0)

#### Anonymous Coward | about 6 months ago | (#46663283)

This is a very old anime on this topic, check it out! Available on youtube.

### People are the easy part to figure out...... (1)

#### Anonymous Coward | about 6 months ago | (#46663297)

..... its the rest of the ecosystem that is the real challenge.

### do the people actually like each other (2)

#### MooseTick (895855) | about 6 months ago | (#46663303)

I wonder if they are taking into account whether the people involved will want to procreate with each other. Just because there are enough bodies to maintain adequate diversity, doesn't mean everyone will happily pair up to make that happen. That is a much more difficult calculation. That being said, if you have a short list of potential breeding partners, some people will become less picky.

Go ugly early!?

### Re:do the people actually like each other (0)

#### Jmc23 (2353706) | about 6 months ago | (#46663593)

Well, that is if people leave the deodorants/perfumes behind.

### How many Earthworms? (5, Interesting)

#### mbone (558574) | about 6 months ago | (#46663307)

To me, the question is not really how many people, but how many earthworms, and in general plants, bugs, birds, animals, etc.? At present, we really have no idea what is needed, nor in how much variation within each species, but I suspect the real answer will always be "more that we think."

### Re:How many Earthworms? (1, Funny)

#### Jmc23 (2353706) | about 6 months ago | (#46663603)

Two of everything should be more than anybody needs!

But horny ones.

### Sperm and Egg Banks? Billions of people available! (1)

#### itsybitsy (149808) | about 6 months ago | (#46663337)

Use sperm and egg banks to, ahem, freeze dry people for the journey. When you arrive you can have the genetic material from billions of humans to mix and match GATICA style. Heck you may just need a skeleton crew and have robotic wombs and incubators to conceive and grow whole new generations of people timed perfectly for arrival. Plus androids to educate them. Could send many more ships to many more star systems this way. Smaller ships means faster and thus closer to speed of light and thus potentially further distances can be covered to spread us out amongst the local star group.

### monocultures (0)

#### johnrpenner (40054) | about 6 months ago | (#46663355)

the GMO mono-culture which wipes out all with roundup, and allows to live only sterile copyright gmo seeds at the expensive of the natural diversity of nature — in mexico, the many many varieties of corn are replaced in america with a mono-culture of sterile gmo seeds — it is insidious destruction of our own planet's natural and abundant diversity.

### Huh? (0)

#### Anonymous Coward | about 6 months ago | (#46663357)

Why is a generation only 10 years?

### Re:Huh? (1)

#### sexconker (1179573) | about 6 months ago | (#46663577)

Why is a generation only 10 years?

These days that's the age at which kids start to fuck and make more kids.

### Why take people? (1)

#### koan (80826) | about 6 months ago | (#46663371)

Just take frozen sperm to diversify.

### Send the Middle Managers first (1)

#### Squidlips (1206004) | about 6 months ago | (#46663375)

We will be sure to follow. Tip 'o hat to Hitchhikers Guide

### Re:Send the Middle Managers first (1)

#### fullmetal55 (698310) | about 6 months ago | (#46663545)

don't forget the telephone sanitizers.

on second thought, didn't the original population die out due to an unsantized phone/

### The question is: (0)

#### Anonymous Coward | about 6 months ago | (#46663379)

Who would agree to die in space and not see your home, friend ans family again?

### Re:The question is: (1)

#### fullmetal55 (698310) | about 6 months ago | (#46663557)

10 years ago I would have jumped at the opportunity.

### So. Let us imagine. (0)

#### Anonymous Coward | about 6 months ago | (#46663383)

I am a man. I am a volunteer to go on such a mission, as part of the first generation. I will necessarily have to breed, in order to do my part for overall mission success. Does this mean I may have to fuck a woman I find ugly, dumb, boring, vulgar or otherwise unattractive ?

### Re:So. Let us imagine. (1, Funny)

#### sexconker (1179573) | about 6 months ago | (#46663587)

I am a man. I am a volunteer to go on such a mission, as part of the first generation. I will necessarily have to breed, in order to do my part for overall mission success. Does this mean I may have to fuck a woman I find ugly, dumb, boring, vulgar or otherwise unattractive ?

### Re:So. Let us imagine. (1)

#### Anonymous Coward | about 6 months ago | (#46663607)

Yes. That is why I'm sending my wife.

### Starship Diversity? (5, Interesting)

On a vaguely related note: Assume you send N ships on this voyage. Do you send N copies of the same ship, and hope the design has no fatal flaw (while acknowledging the advantages of parts redundancy) . Or do you send N different designs in the hope that diversity of design is overall more reliable?

### Duh (0)

#### Anonymous Coward | about 6 months ago | (#46663407)

It's obviously 8 people, like Noah. Welp, that takes care of that!

### Their poor offspring (3, Insightful)

#### fakeid (242403) | about 6 months ago | (#46663453)

While you would clearly be getting volunteers for the start of this task, there is an ethical dillema as far as future generations. Just because parents / grandparents / great-grandparents were totally OK living their entire lives in what would be a fairly finite space, it doesn't mean some members of a future generation wouldn't consider it torture. I guess it might be hard for me to see things from their eyes since they would be born into it, but I'm thinking that after I got to learn some history and see some videos / pictures of Earth, I'd be pretty unhappy stuck on a spaceship forever. I wonder how many would refuse to breed and do the same to their offspring (which would screw up the "diversity", or decide to turn back, or just go stark-raving-mad and murder someone or everyone (destroy the ship), and then your genetic diversity is REALLY screwed.

### Re:Their poor offspring (0)

#### Anonymous Coward | about 6 months ago | (#46663569)

Age-old solution: lie. Tell the kids that Earth was destroyed and they are the few lucky survivors.

### Eight. (0)

#### Anonymous Coward | about 6 months ago | (#46663473)

The Captain, his wife. Their sons, and their sons' wives. That makes eight for genetic diversity. Add some mutations afterward, and you're golden.

### Easy... (1)

#### Kookus (653170) | about 6 months ago | (#46663493)

It only takes 2... duh, that's how we started on Earth!

### Re:Easy... (0)

#### Anonymous Coward | about 6 months ago | (#46663637)

yeah but those two didn't have belly buttons... so who could say they're really human?

### Critical numbers (1)

#### BlazingATrail (3112385) | about 6 months ago | (#46663527)

I don't care if it's enough, just put me on the next spacecraft with Mila Kunis and Scarlett Johansson... Everything will be just awesome!

### Always Bet on Silicoid (1)

#### ObsessiveMathsFreak (773371) | about 6 months ago | (#46663579)

If you send too few people out then production won't be high enough in the beginning. You need to send a fair few billion out to at least the first few star systems so that the population can grow, then once the colony is establish, you need to ship people back to maintain production levels on the home world. This is basic stuff people.

### Inter generational transfer (1)

#### RichMan (8097) | about 6 months ago | (#46663581)

What about intergenerational genetic transfers? No persons genetic info should ever be lost in such a scenario.
Even now we can freeze sperm and ovum.

Also we would not need to send 40,000 people. Just that many genetic samples.

### In the long run (4, Informative)

#### Dorianny (1847922) | about 6 months ago | (#46663585)

Early human population dwindled to as few as 2000 individuals with most living in isolated pockets of a few hundred. Given enough time the population and genetic variability rebounded. Colonization of other worlds is most definitely a long-term project and while a bigger sample might give you better chances its probably possible with far fewer individuals.

#### Anonymous Coward | about 6 months ago | (#46663589)

Increase diversity artificially by having everyone exposed to hard radiation in interstellar space!

42

### Re:Exactly ... (1)

42 thousands?

Maybe he knew more than he thought.

### My science book says 8 people (0)

#### Wireless Joe (604314) | about 6 months ago | (#46663623)

You only need eight people, and one ship that's only 300 by 50 by 30 cubits is enough to carry all the other animals and supplies required to completely start from scratch. Study it out.

### Why research - there is plenty of data already (1)

#### Aviation Pete (252403) | about 6 months ago | (#46663635)

Look at the Pacific and check how big populations on remote islands have to be to stay healthy (Easter Island for example). From that, 10.000 looks much more realistic than 500.

But there is another problem which has not been addressed: Keeping or even raising the technological level of this population. Even a population of 10.000 will be very small in this respect. Evidence: The early inhabitants of Tasman Island arrived by boat and knew how to make arrows and such, but their descendants lost all that know-how. Sure, writing it down will help, but if you need to quickly expand your knowledge (for fighting new pathogens, for example), an isolated population of 10.000 humans will not be enough.

Looking things up in a book is not enough, practice is needed as well. There are plenty of skills which had been developed earlier in the last century which now have been lost for the most part (think of analogue control as an example), even in a population of 6 billion people.

#### jpvlsmv (583001) | about 6 months ago | (#46663663)

How many people does it take to colonize this star system? Apparently more than the 6 Billion we have on Earth, since we haven't even bothered to get off this damn rock.

Send people to Mars first, then worry about Alpha Centauri (which is a terrible place to send people to anyway. The only thing there is a backwaters galactic planning council office)

--Joe

### Math (3, Interesting)

#### DarthVain (724186) | about 6 months ago | (#46663671)

Assuming the closest is even viable, which it probably isn't, 4.2 Light Years = 39735067984839.36 Kilometers. The fastest thing (only thing) man has sent out of our solar system is Voyager 1, which at its current speed, if it was pointed in the right direction would take about 73,775 years to reach the target. Considering you probably don't want to run into it at that speed, you will have to accelerate and decelerate. Which it doesn't have the fuel for (never mind its RTG energy source is only good for 60-80 years), but even if it did would roughly double the time to reach the intended target to about 147,550 years. OK well that's not quite true, it would only add an insignificant amount of time because not a lot of time was actually spent to accelerate in the first place. However in the example below where you do not coast for tens of thousands of years, and accelerate til the midway point and then immediately start to decelerate it would double whatever you speed VS distance is anyway.

Sure you could accelerate and decelerate much harder than that to get there much faster, approaching whatever value of c is currently capable at launch. However by any measure, unless some magic energy source and method of propulsion is devised, the required energy at least at today's standards would require carting around the hydrogen energy mass of our sun for the trip. Some other methods of insitu material gathering such as ram scoops picking up interstellar dust are as likely as the fiction, as again unless some dark matter type thing which is everywhere (presumably) is harnessed, the amount of mass available is pretty low, space as it turns out is pretty damn empty.

Not to mention the weirdness of relative time as one approaches c on a ship compared to Earth, as while it may take less than the 75k years voyager would, here on Earth many more years will have elapsed. As to how many, I have no idea, that is beyond my math calculating ability (as is generally most of what I have currently written I am sure will be pointed out).

Never mind trying to maintain a ship, machinery, technology, or even a society that long!

More likely colonization will involve self replicating and regenerating robotic ship carrying a genetic payload and an informational database (likely with a terra forming mission proceeding it). Which would be more like favorable seeding for similar evolution and life to occur, than an actual "colony". Then again, that would also require pretty adaptive programming and AI, which would likely mean we would probably be fertilizer for our robotic overlords petunia plants.

So I guess I am saying as a thought experiment it is sort of interesting, but at this point (or any really foreseeable point in our future), it is all a bit far fetched by even the loosest standards.

### Send the Immortals (1)

#### TheRealSteveDallas (2505582) | about 6 months ago | (#46663687)

We should combine this thought exercise with the recent article about the theoretical possibility that we will become physically immortal in the foreseeable future. No reason to half-ass nonsense thought exercises. High comedy... to have a few generations of people born and dying on a starship only to hail the call to dock with another ship one day delivering the GREAT news that someone discovered a faster way to travel.

### What is the Female to Male Ratio? (0)

#### Anonymous Coward | about 6 months ago | (#46663703)

Would more Females be beneficial?

If it would then as a Basement geek, who needs no sun light sign me up.

### Different assumptions (1)

#### bravehamster (44836) | about 6 months ago | (#46663739)

Sure, if you *cap* the population at 150 during transit, and don't allow multiple pairings within the same generation of course you're going to kill the genetic diversity.

However, if instead of a generational ship we were talking about hibernation until arrival, 150 is enough to begin a genetically viable colony. How do you avoid the risk of inbreeding? Simple: no cap on the number of children, but no full siblings allowed. Encourage as many different genetic pairings as possible.

### Two... (1)

#### RevSpaminator (1419557) | about 6 months ago | (#46663749)

If you don't mind some serious inbreeding. :)

### Make sure to include a lot of Sub Saharan Africans (1)

#### jeorgen (84395) | about 6 months ago | (#46663763)

They have bigger genetic diversity. According to Wikpiedia:

" The recent African origin theory for humans would predict that in Africa there exists a great deal more diversity than elsewhere, and that diversity should decrease the further from Africa a population is sampled. Long and Kittles show that indeed, African populations contain about 100% of human genetic diversity, whereas in populations outside of Africa diversity is much reduced"

Distribution of variation [wikipedia.org]

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