dystopic dystopic

bussard ramjets, cryonic stasis, and exoplanetary colonization

▼

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
436,432 views 930 replies
Reply #501 from GalCiv2 Forums Top
While gifting water with some of its many life-giving properties, it is unfortunately useless for fusion, which is the domain of protium's rarer brothers, deuterium and tritium.


Well i am most thankful water is useless for fusion.... otherwise, detonate one hydrogen bomb in the ocean and then the Sol star system gets a second sun!
Reply #502 from GalCiv2 Forums Top
we are not able to maintain a fusion reaction because we do not have anything that can hold as hot as 17,000 degrees Fahrenheit
Offworld Trading Company
Reply #503 from GalCiv2 Forums Top
we are not able to maintain a fusion reaction because we do not have anything that can hold as hot as 17,000 degrees Fahrenheit


Actually, we have been maintaining fusion reactions in Tokamak chambers (among other designs) for some time now. Tokamaks use magnetic fields to confine the reaction. The problem is that we haven't made them efficient enough to maintain self-sustaining fusion reactions; meaning we still have to input energy to run it, whereas the goal is to get a net energy output.

I believe these devices operate on the order of millions of degrees Celcius. What facet of fusion technology is 17,000 Fahrenheit referring to?
Reply #504 from GalCiv2 Forums Top
Tokamaks use magnetic fields to confine the reaction.


That reminds me of the spiderman movie. That was awesome special effects for a fusion reaction looking like the sun!!
Reply #505 from GalCiv2 Forums Top
True, the resulting hardware would probably be too large to fit in a normal human cranium. But, once we learn more about the brain, it should be relatively easy to code it into a computer. Essentially like software emulation of the brain.


true, and really not a bad idea. i just think we have a lot longer to go in understanding the brain, whereas cellular micromanagement, so to speak, is already around the corner. and your point about it being a less permanent solution is well-taken. i think there's also an issue of human sentimentality. we're very contected psychologically to our bodies. i guess ultimately i'm ambivalent about it.

Asterisks mine; did you mean to put "easier" there?


yeah. oops   

just 28 to go until we claim lordship over Stardock forums.


  
Reply #506 from GalCiv2 Forums Top
are you still planning on getting a website for the book?


well, the website i have in mind is as much a sort of writing portfolio as well. i want to be able to feature is as part of my CV when i apply for my MFA, which means i want to take time to do it well.

in the mean time, when i have a worthwhile draft i was hoping to see if they'd let me host it on the galactic core; it's already got a pretty strong setup - forums with password protection, quoting built in, etc.

novelettes are usually published in SF magazines, and i'm thinking that'd be the easiest way to make a time scrap of cash here and there before they could be assembled and construed into something more like an anthology.
Reply #507 from GalCiv2 Forums Top
If I were to look at it from a developmental method, I would see the notions of combating aging would fall into general phases as our medical science increases.

As our knowledge of genetics and specifically, cell signalling, increases, I could see medicines ( a good analogy would be to liken them to steroids) that would increase the lafe span of a person significantly, but also have major drawbacks including effectiveness, toxicity ( an interesting irony, lol), cancer and other deadly side effects.

Then an Increase in the effectiveness of the drugs as well as new medicines to combat the side effects the the "Life" drugs. Couple that with more advanced technology concerning implanted medical devices (joint replacement, internal dialysis, pumps etc)

Actual genetic modification of a human is a long way off. First, there's no way in practice or theory (that I have ever heard of), to completely alter a living human's DNA in all of their cells (Adult, child, or infant), nor specifically target a set of cells with 100% efficency. This is why most gene therapies in reseach focus on creating the needed proteins in another organism, harvesting them, and then giving them to the patient in a medicine. It's theoretically possible to alter the genetics of embryos, but there are a lot of ethical concerns on experimitting on people along with some serious scientific disadvantages (like our lifespan - waiting 20 years to see if your experiment worked isn't really efficient)
Reply #508 from GalCiv2 Forums Top
If I were to look at it from a developmental method, I would see the notions of combating aging would fall into general phases as our medical science increases.


Well if you believe the bible as i do, then it is very interesting that a human such as Methusla (however you spell his name) lived for about a thousand years! Then one day God decided the human life span should be around 120 years instead.

Now if i was to compare genetic code with computer software, we humans are in the position of rewriting or 'modding' our genetic code but the question is, do we need access to 'base code' which is kept hidden in Gods breifcase or somthing?

Are we in the position of having to modify a program with no access to base code? It is indeed difficult if not impossible with human computer software, so much more so with the human genetic code?
Reply #509 from GalCiv2 Forums Top
Then one day God decided the human life span should be around 120 years instead.


this would be the day of the flood
Reply #510 from GalCiv2 Forums Top
Well yes and no.

Scientifically, computer code is entirely different from genetic code. Computer code must be compiled into executable which cannot be reverse compiled back to the source with any ease. Genetic information can. Infact, while Computer code must be read and processed to function, DNA can directly intereact wiht proteins and cofactors without transcription or translation.

DNA is the equivelent of source code for the human. We have it all mapped - Ie on paper. We are still trying to figure out what all the different parts of the code do (genes, suppressors, structural support, etc) and we do have a very wide variety of tools and techniques to exammine and look at DNA. Especially with the use of comupters to help pick out patterns and search for certian codes.
Reply #511 from GalCiv2 Forums Top
Now if i was to compare genetic code with computer software, we humans are in the position of rewriting or 'modding' our genetic code but the question is, do we need access to 'base code' which is kept hidden in Gods breifcase or somthing?


well, here's how i would analyze this question. computers have: ones and zeros; genes have: As, Ts, Gs and Cs (you'll forgive me if i don't look them up).

is looking at a series of ones and zeros useful to a programmer? no, not usually -- not unless they already know what they should be looking at. the same is true for base pairs. geneticists, at least as much as i understand it, cannot "see" defects by reading a base pair sequence unless they already know what to look for.

the "base code" in computers is a level (at least) above ones and zeros. it's sets of commands and basic subroutines built up around logic tests. similarly, the "base code" of genes are the way the proscribe proteins and the like, as Denysasis describes above. to add another analogy: we understand the gist of the spoken language, and we know the alphabet, but it's the grammar we're still developing formal rules for. we're learning to understand that part of it very quickly, and many believe it's just a matter of exhaustive empricial study before we have the full contents of God's briefcase, to borrow your analogy. will we ever? time will tell, time and the ebb of flow of social change.
Reply #512 from GalCiv2 Forums Top
Scientifically, computer code is entirely different from genetic code.


Only because computer code is so primative in comparison! I would venture that computer code will 'evolve' in the direction of DNA?

and many believe it's just a matter of exhaustive empricial study before we have the full contents of God's briefcase, to borrow your analogy.


Possibly. However it is more likely that the genetic code we are learning is merely the tip of the iceberg. I would use this analagy... what we are learning about genes is the equivalent to identifying all of the isles in a library without even knowing that there are hundreds of books in those isles!!!
Reply #513 from GalCiv2 Forums Top
I would venture that computer code will 'evolve' in the direction of DNA?


Well, not exactly. Yes, as our technology expands, we will begin to develop and utilize new forms of computing, such as quantum, or even biological using DNA/RNA. However, these forms operate on completely different principles than current computers. Branching to a quantum or biological system would be more 'revolution' than 'evolution'.
Reply #514 from GalCiv2 Forums Top
Branching to a quantum or biological system would be more 'revolution' than 'evolution'.


Well by evolution, i do not necissarily mean logical progressive advancement, I mean the kind of unexplainable massive advancements as the term evolution is applied to life on Earth by the general scientific comunity.
Reply #515 from GalCiv2 Forums Top
The thing is that computer code is so different from DNA that they aren't even comparable. It's not just binary versus quaternary (A, C, T, G), the "hardware" of the cell operates so differently than a computer, that there isn't really any intermediate step between the two. Sure, a computer could emulate the cell's hardware, but that doesn't get you anywhere, thats actually a waste of a great deal of processing power.
Reply #516 from GalCiv2 Forums Top
The thing is that computer code is so different from DNA that they aren't even comparable.


Everything is comparable! it is just a question of by how much?

My logic is comming from the direction that yes DNA and computer code is totally different, but the similarities that are there, are very interesting!
Reply #517 from GalCiv2 Forums Top
Nobody seems to have noticed that Bussard died a few days ago.

http://en.wikipedia.org/wiki/Bussard

Reply #518 from GalCiv2 Forums Top
DNA the most complicated simply computer code in the world.


and according to someone it was all an accident.
Reply #519 from GalCiv2 Forums Top
Nobody seems to have noticed that Bussard died a few days ago.


indeed.



Everything is comparable! it is just a question of by how much?


computer code doesn't build its own hardware in a chain reaction, whereas functioning DNA does (in the right environment).

and according to someone it was all an accident.


theological quips like that are best kept out of this forum, please.
Reply #520 from GalCiv2 Forums Top
Dytopic and Millertime are right, its not really possible to compare Genetic code to Computer code in terms of analogy; althogh the comparison is pretty cool.

For one, Computer code is mathematical; logic based, if you will. Everything done on a computer is a mathematical function (atleast as far as the computer sees it).The code (with no errors!) is all that matters for a result to be acheived. DNA controls via cehemistry. It functions in both terms of the actual code (Which can be pretty flexible at certian times), and in the physical configuration (a specific shape or bend in the chain for example).

Perhaps to put it better, a computer works like this:

Input (my math homework)------>Program/processing (in code) ------> The answer

Where DNA works like this:

Info (Genetic code) -------> Result ( a protein)

Granted this is a really simplified verison of a computer and cell, but in essence, Genetic information is simply converted into another form (a protein). There's no input. A computer program processes an input to find an answer. The answer isn't already in the computer code, where with DNA, it already is there.

what we are learning about genes is the equivalent to identifying all of the isles in a library without even knowing that there are hundreds of books in those isles


You are correct. We have mapped the human genome (Ie - we know the code). However, simply put, we don't know what every part of the code does. That's the 2nd (I think 3rd too) phase of the Human genome project; to identify genes in the code. Even after we find a gene, we still won't really know what it does. First we'd have to figure out what protein the gene codes for. Then after that, we have to figure out where we can find that protein in the human body, and try to determine what that protein does. Its a very complex and long process and scientists approach it from both ends (some start with the code, like the Human Genome project - others start with proteins and work their way backwards).

It'll take a very long time, but eventually will figure most of it out. I don't think this will end the whole nature vs. nurture debate (nor should it). Even figuring out what all the proteins do doesn't address all the complex interactions and process of complex organ systems like the nervous system.
Reply #521 from GalCiv2 Forums Top
Even after we find a gene, we still won't really know what it does.


some genes don't work alone.
Reply #522 from GalCiv2 Forums Top
computer code doesn't build its own hardware in a chain reaction, whereas functioning DNA does (in the right environment).


Havnt you seen Terminator3!? lol

theological quips like that are best kept out of this forum, please.


Not withstanding the quality of Danielost's remark i would say that yes it is your thread, fair enough but it is not your forum.

You are correct. We have mapped the human genome (Ie - we know the code). However, simply put, we don't know what every part of the code does. That's the 2nd (I think 3rd too) phase of the Human genome project; to identify genes in the code.


And then there would be an astronomical amount of inactive information inside DNA as well.




Reply #523 from GalCiv2 Forums Top
theological quips like that are best kept out of this forum, please.


Not withstanding the quality of Danielost's remark i would say that yes it is your thread, fair enough but it is not your forum.


my only problem is others have brought up god and none of them were told to stop. at least some of them weren't.

Reply #524 from GalCiv2 Forums Top
my only problem is others have brought up god and none of them were told to stop. at least some of them weren't.


I think it is good to respect the wishes of the person who created the thread - in that thread but they should not make requests of you outside their thread.
Reply #525 from GalCiv2 Forums Top
I think it is good to respect the wishes of the person who created the thread - in that thread but they should not make requests of you outside their thread.


sorry i have been being nice on this subject. but i can't/won't hide who i am or what i am all the time.