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... Apollo had to stir the tanks to prevent the cryogenic liquid from stratifying in zero-G. If it stratifies it could react if you disturb it by draining a bit for fuel. That isn't an issue for smaller tanks, and not an issue for storable propellants, but it was for Apollo. I expect a large cryogenic hydrogen depot would have the same concern.
How large could that tank be ?
I mean, if you carry 20 tons of ice to the ISS, after hydrolysis you get at best 2/16 (approximate atomic mass ratio of H2O)= 1/8 for H2, that is about 2.5 tons of H2. That is pitiful compared to the space shuttle tank with its 700 tons of propellant.
I am not expert but you won't go very far with that and it looks ridiculously expensive.
Now, with a shuttle C, the possibility to carry 100 tons of ice in orbit looks maybe more attractive.
Would it be better to extract ice from the moon polar region and send it to low earth orbit in a precise spot where it could be captured by some giant net ?
Because here is the point: the perspective to refuel any spaceship in low earth orbit brings completely new horizons to the space conquest, everybody agrees with that.
So far, no one has developed the technology to keep liquid hydrogen liquid. The energy to electrolyze water into hydrogen and oxygen can be obtained, but developing the equipment is the trick.
-- RobS
You mean the only way is to keep it cold?. Then the idea of an inflatable tank filled in orbit with liquid H2 and O2 and the size of the Hidenburg dirigible balloon, is difficult because it needs to be kept cold.
We need to satellite an icy comet around earth to make a reserve of propellant. I hope that when the next one comes to visit us, we could catch it.
Hi all,
a copy of the original article, in french is at:
http://www.globalresearch.ca/articles/RIC111A.html
It says that BLaden had a kidney surgery at Dubai in July 2001 and had met with a CIA agent at this occasion. Of course the hospital as well as the US sources deny.
The Monde, a very serious french journal, says it doesn't trust much these informations from the Figaro journal and thus The Monde doesn't give much credit to this article. The monde expresses doubt about the serious of the information.
So, be warned, it might be just a big crapy scoop.
My feeling is that any further investigations will face a "no confirmation" answer from the hospital or the CIA, but not confirming is not proving. As usual, we have to trust without seing.
And by the way, I also find the US news channels poorly informative. Once, I watched Larry King Live about the snipper story and the expert pschychologist saying that the snipper was a middle age white man, sexually deprived, like PaganToris, and probably a member of the Mars Society. Just kidding (because as you know, all men are sexually deprived). Anyway, one spectator asked by phone to larry King if he knew about a putative french marksman desertor lost in the US. That information has been on internet for at least one week before the LK show and all europeans knew about that desertor. Larry King said he never heard about it.
If you are interested about Bin Laden, here is a copy of the beginning if the article.
" La CIA aurait rencontr? Ben Laden en juillet
Alexandra Richard
Le Figaro, le 31 octobre 2001 Publi? sur globalresearch.ca le 2 novembre 2001
Duba?, l'un des sept ?mirats de la f?d?ration des Emirats arabes unis, au nord-est d'Abu Dhabi. Cette ville de 350 000 habitants a ?t? le th??tre discret d'une rencontre secr?te entre Oussama ben Laden et le repr?sentant de la CIA sur place, en juillet. Un homme, partenaire professionnel de la direction administrative de l'h?pital am?ricain de Duba?, affirme que l'ennemi public num?ro un a s?journ? dans cet ?tablissement hospitalier du 4 au 14 juillet.
En provenance de l'a?roport de Quetta au Pakistan, Oussama ben Laden a ?t? transf?r? d?s son arriv?e ? Duba? Airport. Accompagn? de son m?decin personnel et fid?le lieutenant, qui pourrait ?tre l'?gyptien Ayman al-Zawahari - sur ce point les t?moignages ne sont pas formels -, de quatre gardes du corps,
ainsi que d'un infirmier alg?rien, Ben Laden a ?t? admis ? l'h?pital am?ricain, un b?timent de verre et de marbre situ? entre Al-Garhoud Bridge et Al-Maktoum Bridge.
Chaque ?tage comporte deux suites ?VIP? et une quinzaine de chambres. Le milliardaire saoudien a ?t? admis dans le tr?s r?put? d?partement d'urologie du docteur Terry Callaway, sp?cialiste des calculs r?naux et de l'infertilit? masculine. Joint par t?l?phone ? de multiples reprises, le docteur Callaway n'a pas souhait? r?pondre ? nos questions......"
etc
Hi all,
Since hydrogen is so light and requires big tanks, very inconvenient, is it possible to send water or water ice in orbit, hydrolyze it with solar energy and fill an inflatable tank which could then wait in orbit, like in the ISS and serve for a trip to Mars ?
I realize that sending 20 tons of ice in the ISS is very expensive, maybe more than just sending the hydrogen tank already filled with liquid H2/O2.
Hi all,
It's good to see that some american dare to ask the well founded of american policy. I'm not gonna judge it here, I am not an expert in american policy.
It's good to see Sean Penn in Irak, declaring that he is skeptical about the truth broadcasted by the "official" media system, he admits that he doesn't know. He is not antiamerican by saying that, nor are the guys in this list questioning governmental decisions.
It's always better to question yourself when you prepare to kill children, because:
Sadam Hussein is an assassin and dictator. If I was an assassin and dictator like Sadam Hussein, I would order my militaries to hide very close to school children, or hospitals, stuff like that, obviously without saying anything to the teachers in the classroom or the doctors in the hospitals, and of course don't forget the video cameras, in such a way that when the US bombs fall on the school, the all world can see the poor kids dismembred, and the US militaries won't even be able to pretend they didn't know, it's so obvious, everybody know. The best shield for the Iraky is the combination dead civilians plus cameras.
The Sadam story is a job for smart guys and commandos. Fix him first and please don't tell me you cannot find him. Is the ultra technologicaly advanced US army not supposed to see what you put in your coffee every morning trough the wall ?, is that email not automatically processed by CIA computers when they detect the word "Jihad', are the smart bombs not surgically precise ? that the story we hear the all day long from CNN et al., Is that all false Goebles-like propaganda ?
I am tired of that "Sadam" and the "war to terrorism" show. It makes the US more and more impopular and difficult to defend day after day in the world. Please catch Sadam properly following the international rules, under an international mandat to suit him for war crimes. Do it cleanly and smartly and quickly. If you want to show how great is America, don't kill the kids shielding the tanks but rather, remember july 4th 1997 or July 1969, it takes more efforts, but it is worthing for the rewarding.
Again, I am not an expert, but I think that 200 to 500 commandos/paratroopers precisely delivered on the spot by helicopters at night and in complete surprise could control the situation for maybe just 1 hour, enough to catch sadam Hussein with minimal casualties. Don't send the all US army for that job.
Something tells me that the Iraky's soldiers won't fight too hard to defend their beloved dictator if they think HE is targeted, not THEY and if a bit of propaganda preparation has been done to warn them that "resistence is futile".
Hi all,
Decalcification would not be that bad if it becomes a physiological adaptation process to the mars gravity, one among many other biological ways that the mammalian body could use to adapt on Mars. Bones on Mars don't need as much calcium as they need on earth and cartilaginous bones could have enough stiff to support a 40 kg (mars gravity) smaller body, like for children. Like I said in another thread, adult Martians could be like neotenic humans: kids with cartilages which never, or incompletely resorbs at adult ages. As you know, one important function of the cartilage in juvenile bones is that it promotes growth and bones elongation, but here on Mars, without much physical stress for the hormonal system to stimulate the forming bones and muscles, the presence of more cartilage in bones doesn't mean the bones have to be necesseraly very elongated, meaning that the neo-martians don't have to be very tall.
The bones formation and many other biological processus have to be naturally adatped to Mars conditions. I am not a fan of trying to keep terran characteristics at all cost to slow down that processus. I don't believe exercise is the solution, the colons will have enough work to do, they won't need to add 4 hours of bicycle a day.
Technology and tools will be sparse, colons will rely only on local ressources and frugal technology, using local stones to built their houses, lifting these stones with their own hands maybe, that's enough exercise.
The health problems, as usual, will be mostly for the immigrants, not for the first generation of martians, because by definition, if the neo martians survive the fetal and embryonic development in Mars gravity, they are in business. Those who don't, abortion etc, obviously won't transmit their genes combination further, that's darwinian processus. Then the second generation will be even more fit than the first.
But for the immigrants, no such hope, except medical treatments to relieve their inherent inadaptation.
The first problem is really the embryogenesis. On earth, the human brain takes 9 months, longer than the rest of the body. This is very different of the other mammals, even chimpanzees, whose gestation is usually in the 7/8 months range. So what if the different day duration and gravity impact the gestation time in homo sapiens more than other species ?
On the long term, I think humans can settle on Mars but after an inconvenient initial period with high rate of abortions, malformations, cancers and so on.
For that reason, doctors and molecular biologists will be as useful on Mars than rocket scientists or chemist.
Hi Oker56,
I read some Stuart Kaufman articles a long time ago. If I remember well, he shows that spontaneous order, or low entropy subsystem as you would say now, can arise spontaneously from chaotic systems. In short, order from chaos. This is very interesting. I read also the "what is life" from Erwin Schrodinger and more recently, I plan to digest a book from Leon Brillouin, about the theory of information, entropy, and the link between information, entropy and energy.
Nobody ever tried to make a synthesis of all those theories toward a more palattable definition of life than just negentropic autoorganized systems ?
The cooling process is known, it's just the thermic dissipation, that is, more thermic energy dissipated than energy received from the sun, because of the abscence of a green housing atmosphere. The radiatif bilan is negative on Mars, but quantitatively, I don't know how far it is from a null bilan. Probably not very far since it has been said that very little of green housing gaz, such as CFC, in the Mars atmosphere, would trigger a global warming.
I am not surprised. I never believe in that theory of a northern ocean in a far remote martian past.
4 billions years ago, the sun was much fainter as today (don't ask me the ref, but there is also a mention of that in the original paper in Science ((of this week))
Sources of energy to counterbalance that faint sun could have been volcanism and radioactive decay, plus a thick, greenhousing atmosphere, without those putative ingredients, water was just ice on Mars.
Now the authors in that science paper (Teresa L. Segura, Owen B. Toon, Anthony Colaprete, Kevin Zahnle) said that large meteoric impact created just enough energy to defreeze that ice from time to time, sometimes for thousands of warm years but not much more. Consequently they add that life was unlikely to appear in so short periods of warm time.
Ice or Water, extinct life or not, that change nothing for those who support terraforming/bioengineering Mars.
Hi all,
I repost here in a more appropriate and new topic.
A real problem might be pregnancy on Mars. Days are 24 hours 5minutes, gravity is 0.38 g, food is testricted (only vegetal), etc. This raises many issues regarding people health on Mars, and more precisely about the female hormonal signals and their ability to carry children in those conditions: For example, would those hormonal signals be deregulated and shifted well above or below the 9 months gestation period, forbidding any normal delivery ?
What about Embryonic Neural tube closure / Brain growth at 0.38g ? Will the fetal brain be overgrowth, undergrowth, No one knows.
For 500 millions years, the vertebrate body has adapted his fetal growth at 1g gravity, I doubt the shift at 0.38 g will be without concequences.
Doctors and molecular biologists will be required to fix expected problems like: high rate of miscarriage during pregnancy, grossly developmentaly abnormal babbies (those who survive), growth and mental retardation after birth etc. Systematic delivery by Caesarean might be the rule, at least for a couple of generations, before a normal adaptation takes place. Other problems could be hypertension, heart disease, calcium or other ions defficiency. Maybe Molecular Biology could help by using transgenesis or "genetic therapy" techniques by using Adenovirus or retrovirus to express useful genes to delay or accelerate pregnacy, for example.
Another example, I completely disagree that because of the low gravity, the martian children will be necesseraly tall (as in KSR trilogy and in the recent poem sent by Ms Zubrin: "... they grow taller and taller...").
Body growth is a function of hormonal signal, food income (check the size of nordic population in the starving middle age: were they all 6 feet tall giants ?).
It might well be that under low gravity and no McDonalds available, the children hormonal system won't be very stimulated, they won't produce enough growth hormone like for "small size people", this in addition to the calcium/bones depletion. If nothing is done, I would predict disastrous effects, just for the gravity only, during embryogenesis and early infancy and especially for human, because of the long gestation that the brain requires in our specie. In that regards unfortunatly, the translife experiment (see the Mars Society web site) is partly informative, I mean that mice doing well at 0.38g won't mean human doing well at 0.38 g, but that abnormal mice born at 0.38g will probably signify that it's gonna be worst for us. I hope to be wrong.
Small versus tall... I think the issue could be different if we consider the new martians (or neoMartians) as Terran neotenics. Neotenic organisms are animals similar to their ancestor's fetal stage, likewise it has been said that Humans are neotenic Chimps because they look like chimp fetus. Neomartian could look like terran kids. Being smaller at 4/5 feet, they would request less food, only the brain size and metabolism would be unchanged and they might be better adapted than the 7 or 8 feet tall people described in the KSR trilogy. They might have more cartilages, less calcified bones, less muscular fibers, different heart beating frequency, different cardiavascular system, different gonads and renal apparatus, they might also be less sexually differentiated than we are, they might weight only 30 kgs (on earth) with a 1 or 3 kg brain, who knows ? but if they survive, that would be all right. All those differences don't have to be genetically acquired through mutations, they might be part of the natural capability of the vertebrate body to adapt in the low gravity, which brings me to the next point:
I want to criticise another KSR statement (even if I liked that book): that mutant like Nirgal, with a higher metabolism to resist the cold, would arise spontaneously in the martian conditions. This is pure Lamarckism. Everybody knows this typical Darwinist example: the giraffe neck did not extend over generation because the giraffe needded to reach higher and higher leaves, generation after generation, but because long neck mutants potentially already present in the population were preferentially selected to survive. But the environnent can drive the evolutionary path in many other way than just mutations, fetal development, as cited above, is one possibility. Personnaly, I don't expect the martians to become furry after several generation because it's cold outside, but rather, I expect a tendancy to follow the genetic drift that have started the first humanoids millions of years ago, a trend towards a smarter, highly skilled and brainy humanoid which seems to have stop recently, at least on Earth, but maybe that trend will continue on Mars.
Now that's a lot of new topics: medicine, genetic, evolution... Let's see if people in that list are interested.
Hi all,
Surreallist thread, women only on the Red planet, God of War, Symbol of Masculinity ? It's just an epidermic reaction I guess, more a provocative joke than anything else.
The real issue is pregnancy on Mars. Days at 24 hours 5minutes, 0.38 g, restrictive (vegan) food, etc. What about hormonal signals shifted well above or below 9 months gestation, forbidding any normal delivery.
what about Embryonic Neural tube closure / Brain growth at 0.38g ? Will the fetal brain be overgrowth, undergrowth, No one knows.
For 500 millions years, the vertebrate body has adapted his fetal growth at a 1g gravity, I doubt the shift at 0.38 g will be without concequences. Doctors and Molecular Biologists, men or women, will be required to fix the expected problems: high rate of spontaneous abortion during pregnancy, grossly developmentaly abnormal babbies (those who survive), growth and mental retardation after birth.
For example, I completely disagree that because of low gravity, the martian children will be necesseraly tall (as in KSR trilogy or the recent poem sent by Ms Zubrin: " they grow taller and taller").
Body growth is a function of hormonal signal, food income (check the size of nordic population in the starving middle age: were they all 6 feet tall giants ?). It might well be that under low gravity and no McDonalds available, the children hormonal system won't be stimulated, won't produce enough growth hormone like for "small size people" to speak politically correct. Being tall in rough condition is a disadvantage, you cannot sustain your metabolism by a higher food income, you cannot sustain the calcium in your vertebrae and bones, you just break them. That's just an example that nothing is obvious on Mars except that everything will be difficult.
Austin said:
"I agree with your secound point whole hartedly however, and I'm working on a paper that adress the potential for the production of various materials on mars."
Great idea that you have !
That's the point Austin, since the local conditions do not allow to make a bubble of glass with the martian sand, maybe the concept of enclosed bio-hemisphere has to be reconsidered.
I said before that Martians will have to "reinvent the wheel" in a certain sense. They will have to use artisanal techniques that we consider as primitive, but's that the only way to really expand the initial colony, in my opinion. The only things from earth that the martians should depend on, is the tools and the high technology electronic etc, not the raw infrastructure.
A biosphere is a modern concept, why not to consider pyramids or cubes instead ? could it be possible to use clean martian sand to make thick FLAT panels of glass, possibly reinforced, and assemble those panels on a pyramidal metallic framework, or alternativelly, just sealed those panels with a silicon glue just like the glass panels used make a water tank aquarium ? then put the 500 mb pressure inside.
Use also local stones to make houses. Think primitive.
In Quebec, the first year, the frenchs colons were surprised by the harsh winter and cold temperatures (Montreal is at the same latitude that Bordeau, so they probably expected a similar climate). They relied to much of stocks food, cloths,etc imported from France. All of them from that first colony died if I remember well. That was a disaster. The second year, collaboration with the indians (as opposed to extermination, as most people would think) better planning and use of local ressources allowed the colony to survive.
This shows that a first colony is very fragile and need redondency to have chance to survive and most importantly, usage of local ressources as much as possible.
Hi Soph
I agree with your comments about the unrealistic projects we can read on this list. Many people here are more into science fiction than the immediate technology required to go to Mars.
That's fine to be into science fiction but reallity is more interesting IMO. Like rotating cities digged into asteroids and floating in space just to have a "cyclic" train for Mars. Why not to use just a spaceship ? Other examples are the space elevators, the moving cities on Mars and so on.
It's difficult enough to convince space agencies or private compagnies to built a shuttle-C launcher.
But this forum is a free chat of course, everybody is allowed to expose its mind experiment. That's the fun of this forum.
Idea:
since Mars is full of silicates, why not to add a layer of Martian clean white sand of top of a hemispherical dome of material and then heat the sand layer layer until fusion occured, then removed the underjacent material to leave a pure bubble of crystal.
first point: I think when you are on Mars you should always keep trying to use local materials rather than imported material from earth.
second point: at the beginning at least, some primitive techniques could apply to Mars, such as the egyptian techniques to move and raise big stones into pyramids, but also more generally artisanal techniques that have been replaced on earth by industrial production. I prefer to build myself my small silicate dome/house (like a big igloo) with my own artisanal techniques and with local materials rather than to always depend of the next shipping of titanium/kevlar/nylon ultramodern fabrics send from Earth.
I would hate to go to a place warm at 37 degre C, with a sea, and a night club close to a bar with couch potatoes babes slowly tanning in the hot sun, the death of humankind lay there.
Okay, so maybe living in such a place is bad - long term - but visiting once and a while sounds like a good option, at least to me. If only the couch potatoes were at least a little bit athletic, sailboats and snorkelers plied to warm seas, the drinks were free and Jimmy Buffet tunes filed the juke boxes.
I also enjoy to go there sometimes, diving. So here you mark a real point: if Mars settlement equals working 24hours and 5 minutes a day, the settlers will be exhausted in 6 days, they will need to relax and have some fun, a "7th day" to rest.
Can you really have fun in a confined habitat, just reading, watching TV etc., given the lack of space it's difficult in my opinion. It is then very important to create big spaces for leisure, big parks with warm pools, like an Eden in the middle of a rough desert. Here is another analogy for Mars: the biblical promiss land that MArtians have to terraform and work hard on for 40 years before they or their children can see the blue and the green.
I also found nothing convincing in that article. The gravity, the atmosphere, the ressources, everything can be tailored to the need of a future martian civilization. This is what makes Mars settlements interesting by the way: nothing is easy, nothing is given for free, if you go you have to work hard, but if you work hard, you will be rewarded, either you, your children or your ideas.
This is exactly what made America attractive to Europeans in the past. Same spirit.
I would hate to go to a place warm at 37 degre C, with a sea, and a night club close to a bar with couch potatoes babes slowly tanning in the hot sun, the death of humankind lay there.
Hi guys,
Maybe what I'm gonna say is tough but I think that what we are looking for, safe trip to Mars, doesn't apply to mars direct or any first mission to Mars, since the astronauts will be choosed according to their perfect physical state, like in the first moon mission. Tough guys for tough missions, specially trained under military discipline.
For the first Mars colons it's another story, the differences are that the trip might be shorter than Mars Direct and that the people don't expect necesseraly to go back to earth, so they don't need to readapt to 1g. Once on Mars, the 0.38g could slowly impact the calcium and strenght of their bones, even if calcium supplements are provided and if the calcium release trough the kidney is slowed down . My opinion is that this demineralisation problem will be chronic in the emigrant population only, the first and subsequent Martian generation could be freed of that problem.
When you are a migrant, in a way, you sacrifice yourself to your children because you are always form both side of the road, never completely adapted to any world, that's the price migrants always pay.
Hi Shaun,
don't worry about the math, I get the point: coriolis is really unpleasant. But you, or other, didn't really comment on my comments that:
1) 1 or more g are not necessary, 0.5g or less could do the deal. Everybody seems to agree with that.
2) At 6 meters of radius, less than 9 rpm is needed to create 0.5 g. At 30 meters diameter, less than 4 rpm is needed to create 0.5g.
The question is: at what moment the coriolis force will be physiologically acceptable ? and can we help on that issue by transiently inactivating the vestibular nerves since more of the bad coriolis sensation comes from our inner ear and vestibular apparatus. Remember, the author of this article said " piece of cake that rotation chamber", until he decided to move his head and then he felt sick because of the pain in his ears.
3) a 30 meter radius rotating structure is big but still wouldn't require a tethering cable with a countermass. I remember Nasa's studies of big inflatable structures. A toric inflatable chamber of kevlar or other strong new materials, supported by a flexible metallic exosqueleton for rigidity might be feasible, once inflated, it could be embedded or covered by a thick coat of polymers to provide resistance to meteorit impact, radiation, insulation. In biology one often use such polymers, liquid a ambient temperature, solid at minus 20 centigrade or below. For example, if such a polymer constitutes one sheat of the coating , it would melt at the meteoritic impact and quickly resolidify because of the ambiant cold, thereby protecting the inner chamber of depressurization.
Einstein proved wrong ? I think the general relativity still stands even If I can assure you that I understand nothing of einstein's theories, I just read the papers in scientific journals. It seems that the speed of the light is still the ultimate barrier of the macroscospic world. At the microscopic scale, I am not so sure if the notion of speed has a sense since the notion of position itself is not very defined because of the undetermination principle.
I mean, what about a spacecraft behaving like a particle, escaping its fuzzy position coordinate by "tunnel effect" because of the undetermination principle, rather than really moving in the space time ? but that's completely out of topic of this thread.
In the thread's topic I wanted to say that the name "reds" fits very well because of the indians, I mean the red-skins, who wanted to stay ecologically integrated in their world and refused to evolve, for example they would promote the "warrior's strength" rather than the "geek's ability to use the machine strength". And so the geeks inherited America...
I dug up this article on google.
It's pretty old (1989), but the principle hasn't changed and it gives a fairly vivid description of what Coriolis effects at high rates of rotation must feel like ... not very pleasant!The article ends by saying the worst of the Coriolis problem can be avoided by using a tether and making the radius of rotation much larger, thus reducing the required rate of rotation.
http://www.graybiel.brandeis.edu/article2.htm
Interesting article. Indeed, rotating fast in a small diameter chamber is obviously not the best way to simulate gravity.
I have some comments however: the chamber in this article was too small: 22 feet, about 7 meters (I like the imperial system...) but I don't understand the calculation. The author said he is spinning in a 22 feet diameter chamber (11 feet radius, about 3.3 meters ) at 5 rpm to create a "combined force of about 1.45g", while I got a mere 0.09 g with the following formula:
RCF (relative centrifugal force to earth) = .00001118 x radius (in cm) x RPM2.
Of course, the author is spinning on Earth so we have to add vectorially 1 g but that still doesn't make 1.45 g. With the formula above, with a 330 cm chamber radius he would need to spin at 20 rpm to reach 1.45 g in space (no earth gravity added) which is consistant with what he said later in the article.
1) now 20 rpm is a lot, no wonder the author is sick !
2) there is no need to be at 1 g in space, maybe 0.5 g would be enough to counteract the effect of microgravity.
3) The control mice of the "translife" experiment, according to a report that a read (but a cannot find the link anymore) were fine in a table centrifuge of a 1 meter diameter. I am talking here about the control mice stayed on earth, specifically used to see the long term physiological effect of the coriolis forces, because in "translife" the artificial martian gravity is biased by that coriolis force, so we need to differentiate the effects of 0.38g from the effect of the coriolis generated. Anyway, in short, the mice were able to adapt to the coriolis, on earth.
3) a lot of the coriolis generated sickness is due to the vestibular apparatus. Maybe a possible approach would be to transiantly inactivate the vestiblar nerves.
4) at 12 meters diameter or 6 meters radius, only 8.6 rpm is required to generate 0.5g and only 3.86 rpm for a 30 meter radius structure. Now 12 meters is a big cylinder which doesn't fit in any shuttle. But what about a flexible structures that could be inflated in space ? I still prefer a cylindrical compact symetry in a robust space ship with a little bit of coriolis rather than a thetered rotating structure with no coriolis because....what happens if the cable breaks ?
Mark S, I agree that some scientific missions would need a huge payload, but that would be rare. 90 tons, that's a lot, most often the shuttle as it is now with it's 10/20 tons payload is enough. OK I am not an expert, but I think that it would be difficult to justify a shuttle C fleet with just some rare scientific missions in mind.
To built a fleet of 2 or 3 shuttle C (or equivalent heavy launcher) able to lift 100 tons, every two or three months, is equivalent to a capacity to lift around 1000 tons/year minimum.
3 ISS each year !
Only men to the moon or Mars justifies this capacity, in my opinion. It is unfortunate to say that but, in the actual state of the things, perhaps the US or european space agencies would'nt have any idea of what to do with that big truck, unless they consider Mars or the moon, or unless they consider to build the shuttle C to use it once a year or less. You are not using shuttle C to launch a 3 tons observation satellite in geosynchronous orbit, or even a 5 tons probe to saturn, right ?
However, one day soon, a "men to Mars mission" will be THE priority. What I don't understand is why the USA are waiting for that day to built a shuttleC. Maybe the USA are confident to build the shuttleC very quickly because all the technology is already there ?
Hi
Except in USA and Russia, the space conquest is not very popular. In Europe, space and Mars in particular is not seen as the New New World to conquest. But, even in USA, how many people consider Mars as the new far west ? (well maybe until Odyssey discovers pure gold deposits in craters). This said, america and russia's sciences are built upon hundreds of years of european sciences. We cannot ignore all the occidental scientific monumental marvel underjacent of today NASA's miracles. So I would say that european deserve a good place in the Mars conquest no matter what.
Hi all,
By tethered spacecraft you mean two modules linked by a long cable and rotating around the center of gravity ?
Why not just a cylinder module, in the spacecraft axis and rotating like in "mission to Mars" (I liked the movie for the pictures by the way, but not for the scenario).
This web site http://www.labcentrifuge.com/gforce5.html
gives a Relative Centrifugal force of 0.86g for a 12 meters (1200 cm, feet level) cylinder rotating at 8 tours par minute (rpm) and 0.72g at the head level if you are 2 meters tall. Whatever, 12 meters and 8 rpm don't seem excessive values, if the calculus is right.
Is that so difficult for a metallic structure of that size to hold the constrain ? Is that so bad for the spacecraft stability and ability to maneuver ? It seem so easy to create a gravity that way.
I guess Shuttle-C be would be able to lift a 12 meters diameter cylinder as long as the mass is not greater than 90 tons.
Hi all,
I am also a strong believer that private companies should be more involved in the space exploration and commercialization.
NASA's role is to be more involved in sciences and research in strategic fields.
But one idea today: Mars is not defined in a potential market yet and it is not obvious how companies could make money with Mars, but I am sure that the Mars colonization would stimulate the economy and technology the same way wars do even if it's not their primary purpose.
(Robot: I don't like Osama Bin laden and Saddam Hussein. I hate them ! Bad Saddam ! Saddam = Axis of Evil)
Hi list,
If you want to continue on rumours: for me, the most disturbing rumour was that Osama Bind Laden was used by the CIA for informations, then that Osama had a kidney surgery in an arab country some weeks before Sept. 11, this in presence of a CIA agent who knew about it. You can read that on internet, I hope it's not completely true....I add here, just in case an internet "key word searching robot" classify my post as "anti-uhmarican" that: I don't like Osama Bin laden and Saddam Hussein. I hate them ! Bad Saddam ! Saddam = Axis of Evil.
That secret US agent plays with the arab countries to support US interests is not new. US are not alone, French do the same, remember the Rainbow Warrior ship of Greenpeace, sunk by french secret agents, unfortunatly with some people on board. The english like that game too.
I don't know about Irak (I am not so sure about a war) but I am afraid that american people gonna have to pay a big bill in the future, why ? here is the point:
As Sadam Hussain gonna die one day, the sooner the better, Iraki's people gonna have a more democratic government in the future, maybe in 10 maybe in 20 years, but it's ineluctable, and it's good. But, as those now free Iraki's people will remember the trade blocus of the 90's for food and wealth, I am pretty sure they will suit USA in international courts for the "unjustified casualties of war". Examples: "my brother was starved to death because of the blocus, myself had no antibiotic and had to be amputated, I lost an arm because a US bomb felt on my school while I was a kid, now I want money to compensate, etc etc".
This is a recent recurent pattern: jewish families requesting money compensation for the holocaust, same for forced french workers in german factory, 50 years after. African american requesting money for having been enslaved, 200 years latter, same for Indian americans, legally elected yougoslavian president put in jail for his politic 20 years after. People requesting billions of dollars because they smoked and they "didn't know" smoking gives cancer, etc.
Conclusion: what is legal and acceptable NOW might be juged unlawful in 30 years, and we see that legal, international pursuits can be undertaken as long as hundreds of years later.
Well, I guess some billions of dollars are no big deal for america, It's just that nobody like the idea to pay for the mistakes of the past.
(I don't like Osama Bin laden and Saddam Hussein. I hate them ! Bad Saddam ! Saddam = Axis of Evil
I don't like Osama Bin laden and Saddam Hussein. I hate them ! Bad Saddam ! Saddam = Axis of Evil
I don't like Osama Bin laden and Saddam Hussein. I hate them ! Bad Saddam ! Saddam = Axis of Evil. OK Robot ?)
back to Mars now,