dystopic dystopic

bussard ramjets, cryonic stasis, and exoplanetary colonization

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bussard ramjets, cryonic stasis, and exoplanetary colonization

what will it take?

from GalCiv2 Forums
hello everyone,

i'm a bit of a writer, and i can't help but feel drawn to science fiction. that shouldn't be surprising.

lately i've been reading up a great deal on theoretical physics, exobiological speculation, and all that. i was dismayed at first to learn that the chances of faster-than-light travel being physically possible are slim. it was also pretty discouraging when i sat down and looked at the actual speeds that'd be required to traverse sizable parts of the galaxy in a single conscious lifetime. it was a kick when i was down to learn about how difficult terraforming probably would be. but the more i've been learning, the more i've been excited about telling a different kind of science fiction story.

to draw an analogue to our world, the thing that made both the european colonial age and the modern process of globalization have been technology. it's not that we couldn't go to various places around the world before, it just cost too damn much to make anything worth it. i got my BA in sociology, and these sorts of things interest me.

if FTL travel isn't possible, then more than likely it'll be too damn costly to ever colonize beyond our own solar system as the way it's been envisioned in most of the celebrated scifi universes. But there are examples such as Arthur C. Clarke's Songs of a Distant Earth or Sid Meier's Alpha Centauri where humans colonize to escape destruction on earth.

recently i had the chance to meet both Kim Stanley Robinson and Geoff Ryman. Robinson is a hard scifi writer after my own heart; the Mars Trilogy is a really interesting look at our first attempts to colonize within our own star system. Ryman was actually more interesting to talk to, though. maybe because few people have ever heard of him (i was only there because i work at UCSD where he was being hosted). but i actually got to talk to him. he said he thinks we probably won't ever leave our galactic neighborhood.

i'm interested in writing a hard scifi story (or series) myself. i'm interested from a sociological point of view: what would drive us to colonize space? from a writer's point of view, i want to keep the earth around, so i'm not interested in a flight from disaster. what would societies be like after colonies were established? trade would be difficult, but not impossible. same goes for war.

while i'm certainly interested in contributions along those lines, i'm also interested in learning more about the hard science and engineering behind interstellar travel. i've got a lot of questions i haven't been able to answer through wikipedia and google alone. but i'm not about to list them all here.

it seems like a discussion about real ("real") colonization and space travel could use a place on these boards.

i'll kick it off. i've been reading up on propultion especially, and bussard ramjets seem like the most economically feasible option since they gather their fuel as they go - perhaps especially if it could be hybridized with another form such as antimatter-catalyzed fusion. the wikipedia article on bussard ramjets describe that they'd probably need what is essentially a magnetic funnel or ramscoop to gather interstellar hydrogen as propellant.

The mass of the ion ram scoop must be minimized on an interstellar ramjet. The size of the scoop is large enough that the scoop cannot be solid. This is best accomplished by using an electromagnetic field, or alternatively using an electrostatic field to build the ion ram scoop. Such an ion scoop will use electromagnetic funnels, or electrostatic fields to collect ionized hydrogen gas from space for use as propellant by ramjet propulsion systems (since much of the hydrogen is not ionized, some versions of a scoop propose ionizing the hydrogen, perhaps with a laser, ahead of the ship.) An electric field can electrostatically attract the positive ions, and thus draw them inside a ramjet engine. The electromagnetic funnel would bend the ions into helical spirals around the magnetic field lines to scoop up the ions via the starship's motion through space. Ionized particles moving in spirals produce an energy loss, and hence drag; the scoop must be designed to both minimize the circular motion of the particles and simultaneously maximize the collection. Likewise, if the hydrogen is heated during collection, thermal radiation will represent an energy loss, and hence also drag; so an effective scoop must collect and compress the hydrogen without significant heating.


talk about kick-butt imagery! spirals of heated gas careening towards a ship only to be fused and expelled in a jet plume? sweet.

anyway, i've written enough, and i hope it hasn't put anyone off. some of the the community here has proven to be very well read with regard to these kinds of science, so i thought it'd make a great topic for discussion: all things related to space exploration and colonization with reasonable extrapolations of current technology.

my biggest point of curiostiy was with respect to ramjets, so i'll take the kickoff: could the spiral motion of the inbound gas somehow be harnessed to artficially generate gravity by rotating the ship, instead of producing drag?

any volunteers?

final words: i hope no one minds my double-motive. i won't try to steer any dicussion, though if things quiet down i might pose more general questions to keep it going; i encourage anyone interested to pose your own!
off-topic
436,952 views 930 replies
Reply #276 from GalCiv2 Forums Top
i've only ever read the original Ender's Game.


Definitely read the sequels. The ones that follow Ender seem to be more relevant to what you want; the Shadow series remains on Earth. They're all good though.

P.S.

Speaker of the Dead
Xenocide
Children of the Mind

these are the ones that follow Ender.
Reply #277 from GalCiv2 Forums Top
ever read The Rules of Attraction? it's written (quite well) from at least half a dozen points of view.





one of the star trek novels does that to to an extent


but what i mean is you write an entire story from the federations point of view. and then write the same story from the klingons point of view
Galactic Civilizations IV
Reply #278 from GalCiv2 Forums Top
Definitely read the sequels.


really hope i can make it to the library today.

what i mean is you write an entire story from the federations point of view. and then write the same story from the klingons point of view


i'm not sure i could make that idea into a compelling story. the tension/drama would have to take place primarily within characters' minds and outlooks, since the reader of one book might certainly know how the events themselves will unfold from reading the previous book (in other words, readers of the second book would already know what would happen in terms of external events or historical facts).



well, i got to the library, but didn't have time to check availability before i left. Speaker for the Dead is out until December, and i don't like putting holds on books for personal use (it's a university library, after all, and people might be using it for research). i'll probably just buy the series with my next paycheck.

i did manage to get How to Write Science Fiction & Fantasy by Card, as well as On Writing Science Fiction by the editors of Isaac Asimov's Science Fiction magazine, and Writing and Selling Science Fiction edited by The Science Fiction Writer's of America association. while i don't believe in writing to a formula, advice and exposition never hurt.
Reply #279 from GalCiv2 Forums Top
Some of this reminds me of Asimov's Foundation trilogy. Particularily the 1st and 2nd books and thier focus on separate stories from different times in the Foundation's history and how the Foundation developed from a tiny colony to an Imperial Superpower. The last book kinda has a slightly different premise (The trilogy argues that the future can be mathematically predictable and the 3rd book addresses what happens when the formula is found to be "wrong"). It's a really good series and has a really strong sociological outlook on it - The scifi imagery and science is really left to the imagination, which is nice cause it makes it easier for me to visualize the stories the way I want while keeping the plot upfront and central.
Reply #280 from GalCiv2 Forums Top
(The trilogy argues that the future can be mathematically predictable



it argues that the future can be mathematically predictable up to a point.


and at some points there would be choices to make which is when the guy with brain would leave a movie telling them what the problem was and what the choices were.

but in the third book. an outside force interfered with the whole process. and since they only went into that theater when there was a problem. they never found out if the last question in the book was one of the problems predicted.
Reply #281 from GalCiv2 Forums Top
heh i started reading Card's book on writing sf, and i'm realizing how much reading i should really do. i've never considered myself an sf writer specifically, and i read across genres. one thing he points out, well two actually: #1 is that if i'm going to try and publish sf before i've established myself as a writer in other respects, there's a good chance i'll remain an sf writer in the public's eye throughout my whole career (which isn't really a bad thing to him or me); but #2 is that it's good to be familiar with the genre as a whole. my sf reading certainly isn't that far-stretching, and he makes an excellent point. the best writers know where the stand, and i should certainly be more family with the field than i am if i'm seriously going to attempt to write in it. it certainly doesn't help that i barely read anything until age 18 or 19. it's a little discouraging, but at the same time i never imagined i'd be ready to publish this stuff anytime soon (it might also give me a chance to get my name out there, if only a little, in the general fiction arena before taking the plunge into the community of speculative fiction).



totally random question: what do you guys think about the possibility that intelligent alien life has visited the Earth (or more broadly speaking, our solar system - so i'm including the face on Mars and that sort of stuff)?
Reply #282 from GalCiv2 Forums Top
100% earth


there is god.
Reply #283 from GalCiv2 Forums Top
here is a question


there is one thing that is faster than the speed of light. can anyone tell me what it is. no we do not have access to it yet sort of.
Reply #284 from GalCiv2 Forums Top
there is one thing that is faster than the speed of light. can anyone tell me what it is. no we do not have access to it yet sort of.


do you mean tachyons?
Reply #285 from GalCiv2 Forums Top
do you mean tachyons?



no


think about it


it is faster than anything we have discussed and requires very little energy




Reply #286 from GalCiv2 Forums Top
Are you speaking of the argument that 'thought' is faster than light, because we can imagine and envision crossing vast distances much faster than light can actually cross them?

drrider
Reply #287 from GalCiv2 Forums Top
Are you speaking of the argument that 'thought' is faster than light, because we can imagine and envision crossing vast distances much faster than light can actually cross them?




very good and there is at least two beings who use it. god and satan. of course you don't have to believe that.


of course an ant can make the same arguement against us.
Reply #288 from GalCiv2 Forums Top
danielost please keep theological discussions out of my forum; it's about empirical science and writing. i'd be happy to participate in another forum geared more towards your interests, but i don't want to put anyone off in this forum because it's been quite productive for me so far.
Reply #289 from GalCiv2 Forums Top
in this case i am calling them aliens.
Reply #290 from GalCiv2 Forums Top
totally random question: what do you guys think about the possibility that intelligent alien life has visited the Earth (or more broadly speaking, our solar system - so i'm including the face on Mars and that sort of stuff)?


No. If aliens visited us in the past, they would have to be technologically superior to us now. The only thing we've sent out are probes. One can assume that on the large scale of acheivements/technology, aliens would have the same sequence of technological advancement as us (can't do fusion if you never discovered fire).

Being realistic about speed constraints, etc, if aliens did pass through or visit out solar system, it would have been a very very long journey. That said, communication to the home world would still be needed. We've been shoving radio waves, microwaves and all sorts of radiation out into space for almost 70 years now. It would be logical to assume that the aliens would be doing the same thing, but for a longer period (ie long enought to travel here and then some). Hence we ought to be picking up signals from thier home world (even if they are 100 years old). Strong enough to detect too, after all if an alien ship did pass through what's the point if it couldn't communicate with it's home?

If there are intelligent alien life forms, they are so far away that niether of us can detect eachother due to the time it takes for a transmission to travel that far (millions of light years) or their state of developement hasn't reached the point where we could dectect them (pre industrial revolution - for example).

I think, most likely, local alien life (within 70 light years), if it exists, will be non-intelligent - bacteria, plants, maybe some small animals, dunno
Reply #291 from GalCiv2 Forums Top
long enought to travel here and then some). Hence we ought to be picking up signals from thier home world


actually we did pick up a signal once. we just couldn't find it again.
Reply #292 from GalCiv2 Forums Top
If there are intelligent alien life forms, they are so far away that niether of us can detect eachother due to the time it takes for a transmission to travel that far (millions of light years) or their state of developement hasn't reached the point where we could dectect them (pre industrial revolution - for example).


Well, I was thinking about this, but isn't it also possible that an alien civilization is so advanced that they no longer use radio/EM radiation transmissions? They could have moved beyond our technology long, long ago, and all the evidence of their radio communications had already washed past Earth before we developed the capacity to intercept such transmissions.
Reply #293 from GalCiv2 Forums Top
dang it all... i had a big post in response to what you guys have said, but i lost it again. i'm too tired to do it over (it's welcome week for the freshmen). i have a 12+ hour day tomorrow to boot. so... i've got several things to say that i'd like to think are interesting, but don't hold the discussion up on my account.

and sheesh, talk about the worst week for 1.7 to come out.
Reply #294 from GalCiv2 Forums Top
Well, I was thinking about this, but isn't it also possible that an alien civilization is so advanced that they no longer use radio/EM radiation transmissions? They could have moved beyond our technology long, long ago, and all the evidence of their radio communications had already washed past Earth before we developed the capacity to intercept such transmissions.


Unlikely. After all, the main energy sources in the galaxy are all EM emitters, it is pretty fundamental energy, even if just as a side effect. Its more likely that we just haven't stumbled across the right point source yet ("Space is Big, I mean really, really Huge."), nor understood that what we were detecting included organized signals in the background chatter of the stars.

drrider
Reply #295 from GalCiv2 Forums Top
i had a big post in response to what you guys have said, but i lost it again.


You know, when I am writing a long post, I just highlight the whole thing every so often and copy it to the clipboard. Then if I lose it for some reason, I just hit Ctrl-V.

Unlikely. After all, the main energy sources in the galaxy are all EM emitters, it is pretty fundamental energy, even if just as a side effect.


I fail to see what you are getting at, unless you mean that it is unlikely that there are more advanced means of communication than using EMR.
Reply #296 from GalCiv2 Forums Top
i thought someone was talking about using light to communicate.
Reply #297 from GalCiv2 Forums Top
so advanced that they no longer use radio/EM radiation transmissions?


I was talking about the idea that the EM spectrum, and the need to manipulate it in some organized fashion, are essentially integral to any concievable high-energy physics dealing with the forces of this universe. Therefore highly unlikely that an advanced alien culture of any type would have 'moved past' the use of detectable patterns in the EM spectrum.

drrider
Reply #298 from GalCiv2 Forums Top
Right, thats what I thought. You're probably right.

Though, I noticed you used the word 'conceivable'.
Reply #299 from GalCiv2 Forums Top
You know, when I am writing a long post, I just highlight the whole thing every so often and copy it to the clipboard. Then if I lose it for some reason, I just hit Ctrl-V.


computer crashed. normally i do that too.

Unlikely. After all, the main energy sources in the galaxy are all EM emitters, it is pretty fundamental energy, even if just as a side effect.
I fail to see what you are getting at, unless you mean that it is unlikely that there are more advanced means of communication than using EMR.


no need to use an EM burst to communicate; a highly focused beam would be more efficient and less likely to attract unwanted attention (as long as you new the exactly location of the object you were communicating with). this would also explain the lack of radio signals in our years of listening.
Reply #300 from GalCiv2 Forums Top
no need to use an EM burst to communicate; a highly focused beam would be more efficient and less likely to attract unwanted attention (as long as you new the exactly location of the object you were communicating with). this would also explain the lack of radio signals in our years of listening.


True but you are limited your self to exact point to point communication, which while possible, i doubt it would be practical from a communications sense.

First all, of our communications are burst. When broadcasting something to millions of people, a burst system is more effetive. So that includes everything from TV, radio, cell phones, to GPS.
Secondly, You don't have to worry about a precise location, which allows our communication system to be more mobile.

Also, keep in mind that we are not necesarily talking about signals like the generic SF "Is anyone out there?" junk. Most of our intra-planetary communication goes out into space (radio, tv, etc). One would assume that a civ using EM to communicate, even amoungst itself would be detectable. We've been sending out radio signals since the late 1930's and early 40's that were strong enough to leave Earth. Most of them were TV/radio broadcasts.