But…who is going to the stars?


possums

Kim Stanley Robinson wrote an excellent essay on generation ships — the science-fiction concept of building starships designed to take hundreds or thousands of years to fly to their destination, with generations of people living within them — and summarized all the physical, biological, and ecological problems with them that would ultimately doom such a project to failure. His conclusion is that “Earth is our only home”, which sounds depressing if you look at it one way, but really shouldn’t be, if only we could stop trashing the place.

I agree completely with that essay.

Now Kameron Hurley has written her own excellent essay in response, pointing out that there is a path towards making them viable again. I agree completely with this one, too.

If we figured out how to jettison ourselves from the Earth, we can figure out how to alter ourselves to traverse the incredible distances between stars and even galaxies. And here, then, is the difference in ideas that drives my writing as opposed to that of many other science fiction writers. I understand that space travel and expansion is just as much about altering ourselves, our attitudes, our social structures, our very biology, as it is about altering the places we choose to live.

The one problem is that word “ourselves”. Who are “we”? As Hurley says, the only way this works is if we are plastic and willing to change who we are, adapting to radically new circumstances. We can’t expect to simply put New York in a bubble and lift it off the planet — New York in space is a completely different beast from a New York planted firmly in the BosWash corridor with harbors and airports to connect it to everywhere else. The life of the city would have to change utterly.

The Puritans left England in their ships to preserve their way of life. It didn’t work. It changed everything about them in ways they could not predict, and I suspect that if we could go back in time and show the Puritan emigrants a picture of what America would become and how their descendants would live, they would react with horror and decide that there is no point in leaving after all. If your goal is to shelter your identity, your way of life, and the lives of your children, packing up and moving to a wildly different environment with unpredictable elements is probably the very worst idea you could have. If you want to define “ourselves” as a body of beliefs and ideas, well, sorry, those are extremely fragile and tend not to survive in new environments without some major transformations.

What about our biology? Look at the formation of the Panamanian land bridge and the exchange of North and South American fauna. We couldn’t possibly predict who the winners and losers would be, except, maybe, that there’d be a lot of losers. The grand champion of the invasion of North America was…opossums? Really? Come on. If they’d been sapient, those 5 meter tall phorusrhacid terror birds might have been pretty confident that they were going to kick ass and take over and rule two continents, but instead they all went extinct — as did the Astrapotheria, the Litopterna, the Sparassodonta, and other orders of big strong beasties — and it was the marsupial rat-thingies that thrived?

Hurley is exactly right that generation ships could be doable if we didn’t think of them as shells for people in transit and more as self-sustaining ecological islands cast off to grow and change, but then we have to change our notions of what constitute “us”, because for sure what arrives at a distant star a thousand years from now won’t be Americans, and may not even be recognizable as human any more. We could be building a bridge to Tau Ceti that delivers a chittering cargo of marsupial rat-thingies to a brand new world.

Is that acceptable? Is our vision of ourselves sufficiently flexible that we would consider planting a colony of unicellular eukaryotes on a distant planet to be a success? Would we be disappointed if we didn’t at least get mammals off-world, or are we going to insist on a primate exodus? We’re going to have to have an extraordinarly broad sense of identity for this all to work. Hurley seems to get that, I’d just wonder whether she’s gotten weird enough.

This was a concept I explored deeply in my novel, The Stars are Legion. Because certainly, we will change if we create and inhabit a living organism to which we are intrinsically tied. The Earth has shaped our evolution in every way, and our world-ships will no doubt do the same. Perhaps we’ll never be able to leave these ships. But propelling ourselves across the universe inside a self-sustaining world that can repair and reproduce itself solves the problems of distance and reduces the chance of ecological collapse, particularly if the worlds moved together as a legion and included independent layers of systems so that if one began to decline, another would rise. Think of it as naturally evolving back-up systems.

Exactly. People aren’t an ecosystem. It’s going to require establishing a complex, diverse assemblage of organisms to be self-sustaining, and everything will change year after year. And you aren’t going to be able to predict ahead of time how it will change, only that it will change. And the most fungible, protean, fragile elements will be the highest level bits, things like “societies”.

Those who arrive in the next star system, if they have created societies that allow them to change what we currently consider to be the intrinsically human foibles of war and strife and pettiness and bickering, will require time to adapt to a new environment. Consider how symbiotic parasites can chemically change and shape their hosts to suit them. Now imagine a ship is programmed to merge its flora and fauna with a new planet when it arrives, making the world-ship, now, into a living terraforming machine, a bacterial incubator that rapidly adapts the local environment to sustain its hosts. If symbiotic parasites can do this here on earth, why can’t we hurl something like it through space?

There are nightmares nestled in that idea.

Imagine you fill your ship with high-minded idealists, intellectuals and artists, and plan to export the very best of your culture to distant alien worlds…and by the time it gets there, it turns out that the best survivors are Republican neo-Nazis and televangelists.

Or it isn’t even people who last a thousand years in your starfaring arcology, and the survivors are all marsupial rat-thingies. But I repeat myself.

Try flipping the perspective, too. You’re having a grand time on an ecologically restored Earth, living in balance with all of nature, when a legion of ecological arks from an alien world arrive. They don’t want to exercise the cartoon SF prerogative of exterminating all humans or destroying Earth, they want to merge with us allow change to flow from the natural ecological and evolutionary interactions of diverse species. They aren’t going to kill us, no not directly, they’re going to give us an opportunity to adapt and change, like all good species. Never mind that these kinds of interactions are always catastrophic for some. We send probes up to the oncoming giant space island to figure out what we are going to face, and the astronauts look inside and say, “My god, it’s full of marsupial rat-thingies!”

Or Republicans and televangelists. But again, I repeat myself.

But I am looking forward to reading Hurley’s The Stars are Legion. Maybe I’ll get to it this weekend.

Comments

  1. Siobhan says

    Support for PZ’s marsupial rat-thingy hypothesis: Nixon called his own supporters “ratfuckers,” so clearly there’s a precedent.

  2. says

    I enjoyed Elizabeth Bear’s take on a generational ship gone wrong, with the Jacob’s Ladder series, starting with Dust.

  3. says

    If everyone going up into space for a few grillion years or however long means we get Wall-E robots, though, I’m down.

    Also you’ve just given the first item on my to-do list if I ever get a time machine, show the Puritans what America will bring.

    Quick, convince all the people who say aliens have come to Earth that these “aliens” are actually future humans sent off to survive off Earth in space and another planet and they changed drastically and then invented time machines and went back in time and space to Earth Now to see their ancestors. Once they’re convinced, mention you have a starship to sell to them.

  4. Dunc says

    If you can build successful generation ships, why even bother colonising other worlds?

    And this:

    … when a legion of ecological arks from an alien world arrive. They don’t want to exercise the cartoon SF prerogative of exterminating all humans or destroying Earth, they want to merge with us allow change to flow from the natural ecological and evolutionary interactions of diverse species …

    is more-or-less the premise of Defiance.

  5. alkisvonidas says

    Imagine you fill your ship with high-minded idealists, intellectuals and artists, and plan to export the very best of your culture to distant alien worlds…and by the time it gets there, it turns out that the best survivors are Republican neo-Nazis and televangelists.

    Well, I’d gladly send the lot of them to space…

    OTOH, make sure to leave some telephone sanitizers behind, lest we be wiped out by a virulent disease contracted via unsanitary telephones.

  6. Derek Vandivere says

    That was a bit of the plot of Neil Stephenson’s Eleveneves as well.

    I wonder how attitudes towards generation ships / long term space colonization differ in various cultures. What wth the fact that America’s whole mythology is about Manifest Destiny, I imagine there are some interesting viewpoints from other cultures…

  7. Moggie says

    We can’t expect to simply put New York in a bubble and lift it off the planet

    That’s a shame. It made for pretty entertaining SF in James Blish’s Cities in Flight series. Mow your lawn, lady?

  8. says

    Dunc@#4:
    If you can build successful generation ships, why even bother colonising other worlds?

    Yup! The oort cloud would be a fine place to hang out for … a long time.

    The main point of PZ’s commentary that I appreciate is one that a lot of the “expand into space” crowd forget is that it’s a “to save the village, we must destroy it” scenario: humans, once they have left Earth, cannot and would not remain human for very long. They would evolve and adapt (or change themselves) in order to survive in the new environment and would just become another form of life, as emotionally connected to ancestral humans as we are to Pikaia Gracilens.

  9. says

    Ohh I love these topics!

    I for one have thought for quite some time that any spreading of humanity beyond our own solar system would be done only by our technology, or some future evolved version of such. Space just isn’t hospitable to anything biological.

    Self repairing / self replicating AI however can withstand the rigors of space, shut itself down for long journeys with no side effects. All you need is a power source, and that’s easy.

    I can envision a future where our technology becomes its own sentient race with it’s own cultures, own desires, and that this race would have the compulsion to explore the cosmos.

    I don’t mind that the real masters of the universe won’t be human, or even insist that they be descendents of or created by humans; I just care that intelligence exists because without it, the universe seems kind of pointless.

  10. felicis says

    Once they get to the destination, why would they necessarily want to change again to colonize the place? How many would be willing to leave the only home they’ve ever known?

    Even if they were all marsupial rat-thingies.

  11. says

    Just the bit to get my brain churning on a Monday morning. Thanks.

    Agree with 4. – See KSRobinson’s story 2312.

    Humanity changes if we / in order to make it to the stars – See CStross’s story Neptune’s Brood (sorta sequel of Saturn’s Children) – Stross has biological humanity going extinct and revived more than once by our post-human descendants. (Also a cute critique of present day American economic myths.)

    The “terra”-formers arrive at Earth – OButler makes it sound less horrific by depicting them as rescuers, but I think it would have worked better overall if she hadn’t done that. See her series “Lilith’s Brood.”

  12. dhabecker says

    Maybe we could beam Trump’s genetic code to distant worlds and hope there is a life form there that can replicate. Then use those new ‘life forms’ as slaves.
    Fantasy is much better than reality.

  13. handsomemrtoad says

    RE: “Who are ‘we’?”

    It’s the royal we, which is not the same as the royal wee. The royal wee is usually found in the royal diapers.

  14. Richard Smith says

    Things should turn out reasonably fine as long as one section of the ship is designated “Cyprus Corners.” and put the astronaut Dave Bowman in it. There should be no problem safely reaching a class G solar star.

  15. says

    Is that acceptable? Is our vision of ourselves sufficiently flexible that we would consider planting a colony of unicellular eukaryotes on a distant planet to be a success? Would we be disappointed if we didn’t at least get mammals off-world, or are we going to insist on a primate exodus?

    Depends what the goal was to begin with, otherwise you can’t really measure success.

    But if those aren’t the goals, I think there are ways to avoid those outcomes.

  16. says

    @9, Marcus Ranum

    it’s a “to save the village, we must destroy it” scenario: humans, once they have left Earth, cannot and would not remain human for very long. They would evolve and adapt (or change themselves) in order to survive in the new environment and would just become another form of life, as emotionally connected to ancestral humans as we are to Pikaia Gracilens.

    I think I have to disagree with every point.

    Evolving isn’t ‘destroying the village’ (though I guess I’m not sure what you mean by that). And we could remain human for very very long. Genetics can be technologically maintained, and the environment can be made suitable. As for emotional connection, I think we’d be plenty fond of each other, because people (of whatever species) are far more friendship-worthy than Pikaia Gracilens.

  17. multitool says

    Humans will never live in space sustainably until after we become capable of doing that on Earth.
    .
    Think about it, no matter where we go we will have to create a life environment that can run forever. No climate change deniers will ever achieve that.
    .
    We are utterly stuck on Earth until we grow up.

  18. consciousness razor says

    PZ:

    The Puritans left England in their ships to preserve their way of life. It didn’t work. It changed everything about them in ways they could not predict, and I suspect that if we could go back in time and show the Puritan emigrants a picture of what America would become and how their descendants would live, they would react with horror and decide that there is no point in leaving after all. If your goal is to shelter your identity, your way of life, and the lives of your children, packing up and moving to a wildly different environment with unpredictable elements is probably the very worst idea you could have. If you want to define “ourselves” as a body of beliefs and ideas, well, sorry, those are extremely fragile and tend not to survive in new environments without some major transformations.

    I guess Puritans might be pretty horrified by modern Europe as well … because it’s apparently not very puritanical anymore, perhaps much less so than the US. So maybe they were mildly successful here after all. But the bigger point is that most (or all?) of the relevant changes seem to pertain to what’s happened over time (basically everywhere, at this point), due to things like industrialization, scientific and technological advances, political revolutions, philosophical and cultural changes, and so forth.

    Being in a new location might have had some sort of effect I guess — certainly they had the sense that this entire hemisphere was theirs to conquer, which wasn’t exactly at odds with Puritanical thought to begin with — but at least compared to the other undeniably Earth-shaking changes I mentioned, whatever that may be seems like it has very little to do with what they would be shocked and horrified about if they saw what this country is like now.

    Hurley is exactly right that generation ships could be doable if we didn’t think of them as shells for people in transit and more as self-sustaining ecological islands cast off to grow and change, but then we have to change our notions of what constitute “us”, because for sure what arrives at a distant star a thousand years from now won’t be Americans, and may not even be recognizable as human any more. We could be building a bridge to Tau Ceti that delivers a chittering cargo of marsupial rat-thingies to a brand new world.

    Well, I guess what counts as a “distant star” is arguable. When I’m buying groceries, the store on the opposite side of town is sorta “distant”…. But I would say we’re not going to send anything (people, bacteria, the simplest imaginable probe, whatever you like) to distant stars within a thousand years. Even if it was just “sending” light, that would still only be a thousand light years away, which is not much compared to the size of our galaxy. Compared to the grocery store? Sure, whatever, but the Sun is already pretty distant on that scale.

    How about some other relatively close star systems? I guess we could send something there in that amount of time. Will there be anything living on it? Probably not, at least not by the time it gets there.

    Anyway, I don’t think get where the quote above is going…. Humans have already radically changed our environment. That’s been happening on Earth at least since agriculture started some thousands of years ago, and if anything the changes have only been accelerating ever since. On the one hand, that’s obviously been a disaster for numerous other species (not to mention many people) and isn’t an entirely unvarnished good. On the other hand, we’re presumably adapting to our new environment very slowly in some ways, which probably isn’t all bad.

    Yet nobody (except maybe a smattering of creationists) seems terribly worried that our descendents (if we don’t go extinct too soon) will eventually be non-humans…. After all, maybe we’re already in the process of evolving into chittering marsupial rat-thingies or whatever, without even having to leave home (because that’s of course what life has been doing at home for billions of years, not that I have remind you about that, PZ). Is there really a problem with that? Is there any sense in trying to avoid it somehow or trying to do anything about it, if we’re concerned about ourselves as a special case?

    Should we be just as worried (or much more worried) about genetically engineering ourselves so our species stays more or less the way it is now? I’m sure there are tons of dystopian novels about things like that, if you want to get yourself into the mood for worrying about it. Anyway, I can sort of understand how either scenario might be nightmare fuel for certain people, although I don’t feel that way about our species evolving; but in any case, it doesn’t look we have any non- “scary” choices here.

    erikthebassist, #10:

    I don’t mind that the real masters of the universe won’t be human, or even insist that they be descendents of or created by humans; I just care that intelligence exists because without it, the universe seems kind of pointless.

    Entropy is going to win this game, you know. Super-fancy robots might have a lot going for them compared to us, but they’re not going to violate physics either….

    Don’t worry. Once the universe is a totally pointless place, with nothing in it that has any intelligence or sentience or purposeful behavior or whatever it is you’d like to preserve, then by that time nobody will be around to complain.

    Plus, right now we have purposeful entities like Donald Trump, and eventually there won’t be any of those either. That’s got to count for something. I mean, merely having some degree of intelligence or doing things purposefully or what-have-you is not all it’s cracked up to be, when you look at it that way. I’m not a violent person, so I don’t wish people like him harm, but compared to the shitstorm you get from that lying, hateful maniac … well … give me a lifeless and utterly pointless rock, any day of the week. You know what I mean? And I don’t even like geology.

  19. What a Maroon, living up to the 'nym says

    re consciousness razor @19,

    Come to think of it, various flavors of Anabaptists seem to contradict PZ’s point. The Amish, Mennonite and Hutterite communities in N. America have been pretty successful in sticking to their beliefs and values for the past few centuries.

  20. Matt says

    Adrian Tchaikovsky’s recent novel Children of Time supposes an uplift experiment that goes wrong when the load of primates destined for their newly terraformed home burns up on re-entry and the uplift virus meant for them infects the planet’s extant arachnid and insect population instead. Humanity subsequently all but destroys itself, and the novel follows the development of arachnid linguistics and culture, putting considerable imagination toward what that might look like: a language based on touch sense and vibration, a social structure with males as a barely spider subcaste who may or may not be devoured in the throes of ardor, etc. It’s pretty fascinating and kind of leans heavily toward the ideas here.

  21. brucegee1962 says

    It sounds as if the essay is a distillation of the thoughts that KSRobinson put into his novel Aurora, which is worth reading if you haven’t done so. The whole book is basically an extended argument about why the whole concept of colony ships is a bad idea. I think in some ways, it makes one good point — that making our own environment, to which we are adapted already, into a sustainable system ought to be far easier and also more urgent than spreading elsewhere. I think he oversold the argument that the idea is unworkable, though.

  22. johnhodges says

    I’ve been a science-fiction reader all my life, but maybe I’m just getting too old for this sort of thing. Here on Earth, now, we are in the middle of the Sixth Great Extinction, and seem bent on making it even more thorough than we have already.

    We consider people like Genghis Khan, Tamerlane, Hitler, Stalin, Pol Pot, to be great criminals (The Greatest!) because they killed millions. Considering that the business-as-usual scenarios for Climate Change include some significant possibility of the collapse of our current civilization and the permanent reduction of Earth’s carrying capacity, possibly even down to zero, It may be that Rex Tillerson (CEO of Exxon for some decades) may be the greatest criminal that the human species will ever have.

    In my more cynical moments I have posted: In two hundred years there will be three species remaining on planet Earth; humans, cockroaches, and algae. Among humans, there will be a slave class that eats the cockroaches and algae, and a master class that eats the slaves. And all of them will be Christian.

    More to the present, I hope that civilization will last long enough for me to die a natural death.

    I hear posters waxing lyrical about new and exciting developments in this or that science or technology, and I think “You have to remember, each of these developments will offer exciting new possibilities for weaponry also.”

  23. says

    PC, the Xenarthra were at least as much of a northward success story as the opossums. Multiple species of ground sloth and armadillo, chlamyphoridae, tree sloths, and anteaters crossed the land bridge, and speciated further. Ground Sloths in particular became keystone species in North America; yucca, avocado, and paw paw seem to be dependent on some sort of large frugivore to spread their seeds; it’s fortuitous for these plants that the same species that wiped out the ground sloths also has a thing for high-calorie fruits.

    I think you have a bit of a didelphidae bias; armadillos haven’t trundled north to Minnesota yet (YET) so you just assume that opossums are the better example. For all you know these generation ships will end up full of lethargic mossy leaf-munchers or fuzz-bellied punch bowls.

  24. fentex says

    It’s been obvious for a long time that ‘we’ will never colonise other star systems. The requirement to survive indefinitely in space will require us to change, dramatically.

    And once you can survive in space you don’t need planets, all the resources you require are more easily gathered away from gravity wells.

  25. unclefrogy says

    well I too doubt we will leave here before we are able to take care of here in a sustainable way.
    as far as what we will be sending and what will arrive on such a long trip.
    It is clear to me from my own limited understanding to biological systems that they are always in constant flux. There is no way to control that for anything like the extended time that such trips would have to travel. It would be a relatively small place and a rather large Petri dish inoculated with numerous species, including the vast colonies of necessary bacteria living in the guts of all of the “higher” animals that will by necessity be traveling along with the humans. what are they going to do in that long time and what are they going to do when they are released in a new environment that has never seen then nor they it?
    what will arrive will probably be something akin to what happened to the first canned food shipped by sea. lots and lots of fetid bacteria to seed the planet with earth life.
    uncle frogy

  26. wzrd1 says

    Such poppycock! We can have a generational interstellar travel right now, with our current technology and with a properly regenerative ecosystem immediately.

    First, we need radiation shielding. Oxygen, hydrogen and nitrogen are excellent shielding, even as gases, add a magnetic field, you’re doing well. Add a reinforcing energy source and magnetic field, you’re golden. Fusion would be ideal and there is already an excellent fusion furnace available, which fits all of the qualifications.

    Second, one needs a sizable area for a population, with a buffer excess to survive any potential disasters. A quick tablecloth calculation yields that at around 196.9 million square miles, while still maintaining a healthy one gravity.

    With those pre-existing capabilities, that can bring one star within 0.32 to 1.44 light years (0.10-0.44 pc) in about 1.3 million years and one coming between between 0.13 and 0.65 light years (0.04-0.20 pc) between 240,000 and 470,000 years from now.

    Of course, that’s assuming Sol’s proper motion continues and that humanity stops fucking up its current “space ship”, which humanity has well evolved to suit.

    Making interstellar travel by intentional vector changes, that’s problematic at best. The best designs I’ve observed thus far range from cylindrical and wheel designs, at the very limits of our current design capabilities, with minimal shielding through the substrate of a spin induced pseudogravity field and a propulsion system that is currently outside of our technological capabilities (not to mention a dearth of energy sources to last for the duration of such an epic journey.

    One problem with such a lengthy journey was well described in Garden of Rama.

  27. says

    Me the thinks Generation Ships will be thwarted by one of its generations being convinced that it’s a grand conspiracy and explode a hole in the hull to “freedom”.

  28. Hatchetfish says

    You libel marsupials with comparisons to the American Nazi Party. They’re pretty much defined by their care for offspring after birth, after all.

  29. brett says

    I’d be with whatever transhumans end up living off-world (if they do at all, and they presumably will have to eventually), as long as they’re friendly to baseline homo sapiens and we can still reflect upon our shared heritage together. I’ll third those who pointed out that people who modify themselves to live successfully in habitats and generation ships may decide there’s no point after all in changing their descendants to live on worlds again.

    And that’s how it will happen, in any case. A generation ship is going to be the project at a long end of experience and history of making and living in space habitats.

    I do have some quibbles with Robinson’s essay. You don’t need the generation ship to be a perfectly closed system, since you can bring along expendable resources as well. It’s going to be titanic in any case, and you’ll be dropping off parts of the ship to reduce the mass you need to decelerate at the destination. If a vastly more robust recycling system can be built that only recycles, say, 80% of water and resources than a much more frail one that can possibly get 99% with heavy maintenance, then it might be better to go with the former and bring more water and other resources on board.

    Actually, come to think of it, weren’t people living life-spans in the 200 years’ range in the Aurora setting? Or even 150-180 years without the sabbaticals back to Earth? It seems like some of the crew should have lived through the entire transit.

  30. John Morales says

    wzrd1 @28:

    Such poppycock! We can have a generational interstellar travel right now, with our current technology and with a properly regenerative ecosystem immediately.

    No. You imagine we (humanity as a whole) can do so. Not even slightly.

    You clearly have no idea of the challenges involved; among other things, one essential requirement would be a functional ecosystem capable of sustaining a human population for generations, absent any external supplies.

    You’re obviously a SF fan, so here’s some good reading on the topic from Charlie Stross:
    http://www.antipope.org/charlie/blog-static/2009/12/2009-redux-part-3.html

  31. John Morales says

    PS Hopefully in fair use and because I think it would be helpful if more people read this stuff, I here include an excerpt from the post to which I linked:

    What is the minimum number of organisms one needs to create a stable biosphere — on a space colony or generation ship? (Hint: the action is all in the comments, and the answer is a lot more complex than most of the early commenters seem to realize.)

    Mechanical problems associated with space habitats/generation ships — ditto on those comments.

    Designing society for posterity — never mind the propulsion, engineering, or life support side of a generation ship: what kind of society would make it to the other end of a multi-thousand year journey intact? (Again: the comments are enlightening, in a gruesome kind of way. It’s amazing how many space colonization enthusiasts love the idea of (a) nautical-military hierarchies or (b) theocracy.)

  32. gijoel says

    On the other hand we make a living spaceship and after a few generations the ship has to deal with a bunch of colonist decedents who are making hats out of the ship’s life support system.

  33. KG says

    Helge@12,

    Yes I greatly enjoyed Charles Stross’s Neptune’s Brood – but I get the feeling it was written in response to something like:
    “OK, Charles, you say you can write SF about anything. So, write a novel about intelligent squid and an interstellar financial scam!”

  34. brett says

    @33 John Morales

    Wzrd1 was referring to Earth as a spaceship. Earth has a surface area of 196.9 million square miles.

    I think any generation ship is going to be coming out of a pre-existing history of long-term habitats located light-minutes away from Earth, and centuries of experience with that beforehand. If there’s no way to build stable governments on-board said habitats, then generation ship journeys simply won’t be done. Or at least I hope they won’t be done, since that’s a lot of resources to waste on a big mistake that gets tons of people killed.

    That said, a multi-thousand year trip is a long time. It’d be smarter to break it up into smaller trips between nearby stars as much as possible, even if that adds a considerable amount of time to the trip. The intermediate stops don’t have to have habitable planets, just accessible resources and energy that the ship can use to build a bigger habitat for rest and reassessment while doing a complete overhaul of the ship for the next jump (spending a few decades there while doing so).

  35. a_ray_in_dilbert_space says

    Wzrd1: “First, we need radiation shielding. ”

    Yep. A whole metric fuck-ton of it–about 140 g/cm2 of surface area for the ship–that’s about a 2-foot thickness of Aluminum. And that’s just for the galactic cosmic rays–heavy ions like iron that will shred your DNA. It will barely touch the neutrons formed as the galactic cosmic rays are stopped.

    So, I think your suggestion that the problem is solved might be just a tiny bit optimistic.

  36. wzrd1 says

    @John Morales # 32, I was actually joking. That is readily apparent if you noticed the three measurements that I provided, which describe earth in a specific way, such are landmass area. :)

    The punch line being, we’re already traveling through space on our own natural habitat. We just need to stop fucking up that habitat before we render it inhospitable (as was explored in the last two Rama series books).

  37. wzrd1 says

    @a_ray_in_dilbert_space #37,

    A whole metric fuck-ton of it–about 140 g/cm2 of surface area for the ship–that’s about a 2-foot thickness of Aluminum.

    You’d need far better than that!
    Bremsstrahlung from bombardment of that aluminum would be a bear! Maybe a meter of aluminum, then a meter or so more polyethylene over a meter of water might tame the worst that the universe can throw at us.
    Yeah, dragging a planet along is sounding more and more practical than shielding against radiation in other ways. ;)

  38. DanDare says

    Nice nod to the Star Lost above.

    Hull Zero Three had all the nightmare elements. The ship is approaching a target system and preparing engineered organisms to forcefully alter native life to its needs. Other AI processes are generating humanish agents to thwart this plan. Evolved hive humans have infested part of the ship and have plans of their own. The command crew are intelligent shrew thingies but they have died out and left their own AI in charge of stuff.

    My own assessment is that if we survive then we will exploit our solar system economically. A lot of industry will happen in space. Improved robotics and AI. Humans will be out there a bit and we will gradually adapt to life in space but the bulk of humanity will stay right here.

    Space dwelling life will lead to many speciation event even if we don’t accelerate the process by genetic engineering. It will be Cambrian Explosion 2.