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Ive always found this concept really facinating, and i would love to be able to somehow bring it a little bit closer to reality.
Nasa did a study too, im not sure if you have this link.
Advanced Automation for Space Missions
The biggest problem i can see is reducing the size of the initial seed. During the 80's, it couldnt be reduced below 100 tonnes for the initial seed, mainly because you need foundries and smelters for production and these are all heavy items. However over the last 10 years Rapid Prototyping Devices (born out of stereo lithography) means complex machines using a variety of materials can litterally be made in one go from the ground up.
An american company has made the same point at this website.
On another note I would love to contine my studies in either of these two areas - if anyone has any ideas, let me know!
If it was an optical telescope, it needent necessarily be on the other side of the moon. It would simply need shielding from sunlight and earthshine and would be fine. Radio telescopes, need to be on the 'dark' side of the moon in order to be shielded from any radio transmission interference from the earth.
If you combined it with the von nemann concept of self-replicating machines to build it in place, then you could quite feasibly build a telescope larger than any on earth with better view than any on earth.
Ive been a long term advocate of sending machines to the moon to do our dirty work, and a telescope on the moon would be a good first stepping-stone to both prove the technology and provide a decent, small and immediate application capable of being useful straight away.
When im drunk, i sometimes drive on the wrong side of the road.
Why would we need that? Each individual colony having its own political structure and a global congress (a la UN) to resolve trade disputes etc, wuld in my opion lead to far more beaurocracy and a far greater possibility of civil war. There arent going to be a great number of people on mars for a very long time and i seriously doubt we would want to commit to a course that would represent a step back in terms of democracy and a waste of valuable manpower.
The best course would obviously be a global democracy of some sort, as in one government. Let people get on with their lives and a colonising a new world without commiting themselves to a backward form of government.
Why are people so keen to be a law unto themselves as soon as they leave this planet, what is everybody running away from?
What about it? ???
The only advantages of heavy industry in space is to serve a space based economy. The only benefit is that you can avoid the launch costs of materials by mining them whilst theyre up there. However you wont have a customer to sell to until lanch costs fall, so unfortuantely as soon as asteroid mining becomes viable it will most likely become less profitable.
I firmly believe that once the space based economy starts, it will explode, simply because once there is someone to sell products and services to then there will be money to be made, and business plans are no longer based on conjecture. Whoever makes the first steps, will bare the greatest risks, but have the most to gain.
That said, you cannot begin heavy industry in space with the so purpose of serving itself, this will make no money.
On the technology side of things, zero gravity can sertainly reduce the energy needed to perform certain tasks, namely transportation, but it makes the actual task itself far more complicated and expensive. How would you hold your cutting tool against the asteroid in zero-g? Whilst operating in orbit how would you prevent material (dust is lethal in orbit) from leaving the operation and damaging satelites and stations in orbit? How will you dispose of the excess material? etc etc
For every question you answer, there will always be a dozen more that your answer creates. Off-planet heavy industry is an exceptionally tricky enteprise which has not (yet) been satisfactorally investigated.
Using a centrifuge is an obvious and good basis for developing an idea, but the problems are far more complicated than that and cannot be solved in any off hand kind of manner.
Utilising off planet resources represents a big leap in technology, in every aspect involved from life support to the manufacuring involved. In the terms of the new world all they needed were ships; ships had been travelling longer distances than the trip across the atlantic for hundreds of years, and sturdy ships capable of the trip had been around for over a thousand.
Space will be indusrialised and colonised, but the potential benefits (financial or otherwise) arent as large, as needed or as obvious as they were in the case of the new world. If mars had a breathable atmosphere and fertile lands, then this would be a very dfferent matter.
Nick Ramsay - 21 - UK
3rd year of a 4yr Masters course in Aerospace Materials.
Currently support myself though research scholarships(im in USA at the moment conducting research on ferroelectrics), and through my training with the RAF (Royal Air Force) as a pilot. Im not fully commited to them, but they pay me and teach me to fly, am also on the lookout for a possible PhD.
Havent chosen a career path yet - it was originally astronaut, which is why i speak languages and am learning to fly and scuba dive etc, but im currently eyeing up other options.
The lack of gravity in orbit and beyond in itself produces processing problems which have yet to be properly addressed, let alone a whole host of other issues.
The new world represented a vast new open, and fertile/rich area, where current technology and practises could easily work. Us europeans had spent hundreds of years fighting each other over the best bits of land here, and there was a whole continent of fertile land and resources, a boat ride away with only some ill equiped natives to protect it.
They dont compare well really, except maybe in the spirit of the adventure a hundred yeard later. Columbus has been to orbit and the moon and back, the government found no great riches or oportunities and moved on.
Its probably worth pointing out that the scientists arent worried about martian microbes contaminating the earth. The samples are quarintined because they are worried about the earth contaminating the samples. They need uncontaminated and unafected samples to study soil compositions and surface conditions, and of course to see if there are any microbes there.
My point is that you are being to harsh on them. They were never designed to fully repace humans and for a very long time will be incapable of doing so. Robots were sent out because it was the best and only option we had and currnetly have. Even when we do have a permanent presence they will still be used - they will be able to increase the capabilities of our crew and lighten their workload allowing them to concentrate on the big questions.
I just wanted to put my thoughts on this matter past you guys.
A lot of people have been saying we shouldnt overly criticise the shuttle lest congress feel chastised and refuse to go out on a limb on future space projects.
However my feelings are that if the shuttle were retired now, there would quickly be a wave of nostalgia afterward, praising the 'ageing workhorse' that got us all so far, how it was way ahead of its time, how brave and american all the pioneering astronauts who flew on her were and how it is has laid a great foundation for future efforts. Im sure there would be petitions in no time calling for the shuttle to be brough back into service (just like people who called for the venture star to be finished), and im sure congress would quickly approve the next big project.
My point is that history will always remember the good points and gloss over the bad points - we should retire the shuttle, gracefully; it will quickly be replaced, and hopefully NASA will get it right this time.
The only reason we have any of the questions we do now is because the robots went out there and couldnt answer them. We send them out to do measurements and collect data, and they invariably come ack with more questions than answers, but thats what exploring is all about. We dont have any manned interplanetary capability and rovers are doing a fine job until we do, they keep our scientists busy and our pulic intersested. If it werent for robots alot of people would still probably argue there were little green men running around - theyve brought us this far and theyll carry on helping us in the future.
erm...
Robots in space are a reality, they work very well to extend our capabilities and our horizons at a fraction of the cost and danger. They have also gathered every piece of information we have concerning anything further than the moon. Not bad really.
Im all for manned missions, but until then robots is all we have, and thats not so bad. They may be slow and have short lives but they get the job done.
Nasa have done a couple of tests, using individuals and small groups, but i think the one you are refering to involves a larger group and something like 2 years isolation time. And im pretty sure they are using biological processes - the samller scale runs did, they litterally just used plants, and they got a wealth of inforamtion out of it. Lets hope they have better luck than biosphere 2 (although im sure they arent attempting as complex an ecosystem as that), or the space station trails!
I read (in the case for mars, no less) that despite the sandstorms looking impressive in terms of blurring our view of the surface, that they are actually really quite tame, due to the very low pressure at the surface. Which makes sense really, because you need something to blow in order to pick up the sand in the first place......
The quote for being able to produce alloys that are 300 - 900x stronger than their earth based counterparts is wrong. Also the effect of gravity on the alloying elements of materiasl is a commonly held misconception. Temperature and compositional gradients drive the formation of alloys also affected by size factors, electrochemical factors and valency factors ala Hume Rothery.
The truth of the matter is that whilst gravity can have an affect, mostly through convection currents, its affects are easily dealt with either during casting or via processing - as everyone jas done for the last few thousand years before we had access to space.
At the end of the day, materials science is still quite a basic process when it comes to making new discoveries - engineers and scientists commonly produce thousands upon thousands of different compositions and test them all for their properties, and when they do a find a new or unexpected property they attempt to explain it, and then work on it further - but there is no way to predict totally new materials. It is nearly impossible to go through a thought process and expect to be able to predict exactly what you will produce when dealing with new compositions and processes.
I have no idea what materials will come out of a space programme and i have no doubt that they will be both innovative and better than their previous counterparts for what they are designed for - but these materials have not yet been discovered nor are they likely to be until there is a lot more infrastructure up there.
In terms of current materials that could be applied to the space programme, as robertdyck alluded to, there are often alot more factors that need to be taken into account than weight alone. safety is always of primary importance - and alot of materials werent developed to be used in, nor have they been tested in the extreme conditions we would wish to use them in.
Btw, carbon is the future and not just in terms of nanotube composites. Also a friend of mine is coming to end of some great pice of work which should do for titanium what the Hall-Heroult method did for aluminium. Exciting stuff. (God im a geek! ??? )
nick
How about this.
A MAV (mars ascent vehicle) and a hab are sent to mars. The ascent vehicle produces propellant and the hab builds up fuel for the rover (for example) and checks everything is working. Then at the next window the cycler is launched, with crew. When they arrive they depart from the cycler in a lander(which is just another mars ascent vehicle) which produces propelant whilst they conduct their mission. Then when the cycler next comes round they hop on board using one of their MAVs and of they are home. Coincidentally the cycler has brough the next crew with it (with or without their own hab travelling in tandem) who land in their MAV (clearing a docking space for the ascending crew) who then conduct their mission and return on its next pass etc etc.
It would essentially seperate crew from cargo, alot like the way the OSP is designed to improve effiiency by catering for crew transport needs only.
Pros
Reduced costs - Whilst the cycler would cost more in the beginning (it would be larger and designed to last longer), each consecutive mission would save on launch costs and interplanetary propellant costs and thus overall mission costs and as such would save money in the long run.
Programme continuation - The constant (and effectively free) ability to send people to mars would almost gaurantee a maintained sequnce of missions and eventually presence on mars.
Cons
No abort - the inability to return to earth in an emergency should the crew need to would be problemtic (but only for the first missions - as increased infrastructure leads to increased capability and thus safety)
Long return trip - As i understand it the return leg of the journey is considerably longer than the outbound journey thus exposing astronauts to excessive radiation and long term zero-g(using two cyclers, one for each leg, would alleviate this)
Transfer time - since the cycler is not designed to slow down on approach to mars, it wouldpass by at high speed and the transfer window would be both short and dangerous - this is my opinion, i do not have the facts or stats.
Any other additions?
nick
its a good idea - especially considering how much publicity mars missions are getting at the moment. However we would not be promising nearly as much financial or near term economic gain as colombus was promising....
The x-prize competitors would love to do this but simply would not have the money.
nick
So are you no longer advocating that we should be promoting the mission as one-way?
The mars-direct plan already includes a 500-day surface stay and a cycle of crews arriving and departing from the surface ( i cant remember if there is a small overlap, or if each consecutive team just misses the last), each bringing with them their own habitat and equipment which whilst originally might be dispersed over an large area, would eventually be brought together in order to assembled a small base.
The whole basis of the mars direct plan is in-situ resource utilisation, but, WE DO NOT KNOW HOW TO GROW FOOD ON MARS. The point is that each crew is taking with them ALL THEIR NECESSARY CONSUMABLES, and yes for the WHOLE 500 DAY STAY, as such they will have to return, or starve.
Luckily they will be conducting handy resaerch whilst they are there, and upon their return they will be able to tell us all the wonderful secrets concerning living on mars. Then, armed with this new found knowledge, we will be able to consider colonisation of mars.
This way we get our handy base, and nobody starves by going on one way missions (which they are apparently now allowed to reurn from).
N.B I dont know where you got a 20 month surface stay from, if they waited this long to leave theyd have missed theyre "FLY-BY".
We could swap personel every few years at their request, which might answer your moral questions.
Whats the difference between swapping personel and returning them?
Are you suggesting we have permanent residents or residence?
Any mission we launched now would be designed to take everything they need with them. We cant grow food there, because we dont know how. We need to send a mission to answer all our questions. Then, and ONLY then, can we put a mission together with all the right tools, supplies and equipment necessary to make an attempt at permanent residence. All the kit sent on previous missions would still be there and available for their use.
It would be sheer folly to send the first mission/colonists to mars and ask them to work out how to live there and hope any equipment or supplies they will need to sustain themselves is included in their initial supplies. All equipment, of course, except that needed to provide them the option of returning home in case someone got their theories or calculations wrong - because that same somemone thought it might be too dangerous.
The everyday shaving/hair cuts will probably be dealt with the same way they are on the ISS, thats what its there for really - to give us the necessary experience for us to iron out these small details. Admitedly keeping them busy on the flight will be an ineteresting task, NASA has traditionally been able to keep astronauts busy with either maintenace or scientific study, but i cant imagine the transfer vehicle will take more than 2 crew to run, day to day. Maybe we should look to the navy and how the submarine crews keep themselves entertained, it would probably be a god analogue.
nick
yes, but they are taking all their supplies with them. The kit theyd need for a permanent stay would be completely different, and we frankly dont know what it will be yet. We can make good guesses, but we still just dont know at the end of the day. We need a manned mission to answer all of our questions before we can risk attempting colonisation.
nick
I dont think people would be comfortable with the first trip to mars being one way. As much as we would'nt like to admit it, there is still so much we need still dont know, and so much we need to find out.
A mars mission would most likely be able to answer every question we have, but the crew should definately be planing on returning if only because there is a possibility we wont like the answers we get. I'm all for sending colonies, but not until we atually understand the place we are going to.......
Nick