huangyhg

time to start designing orbiting production facilities?
so like the title says, with all the new proposed missions for orbiting launch facilities, lunar bases, and expansions for iss, do you think it is high time we start designing production facilities for use in orbit? this would negate the cost of bringing all the materials needed for these things from earth. this may also reduce the power required to machine and work metals, as the power needed to move them around is reduced due to a smaller gravitational force acting on the materals. i for one, believe that an in orbit production facility receiving materials from drones that are mining asteroids would be of greater benefit to space exploration than a lunar base. discuss
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seems to be absurdly premature. the facilities required to make just the smaller pieces of the iss were hundreds of times bigger than the iss. it would take multiple decades to just build the facility itself.
ttfn
i probably wouldn't have used ir's adjective, but i think it is premature, unless your planning horizon is several decades.
i think there are huge advantages to creating structures remotely, and it will take a lot of time to recoop the capital investment (lifting the factory).
i imagine that for the lunar base they are already planning production of o2 (and h2o ?) from local materials (as well as recycling). manufacturing building materials is probably quite a ways down the list (unless its creatice ways of using soil materials, to make a pressure shell??).
i agree with the others. i'm tempted to say that with anything like current technology it's probably a ways off.
you're proposing unmanned space craft to mine asteroids and transport the raw ore back to an orbiting facility. this in itself is highly challenging. you have to find an asteroid, confirm it has usefull accessible ore, extract the ore, transport the ore before you're even at the start point.
you then need some kind of foundary in your orbiting facility which will require massive amounts of energy.
then you need machining & fabrication facilities...
kenat, probably the least qualified checker you'll ever meet...
its not much closer than it was 30+ years ago when lots of folks were all gaga over giant solar power satellites. orbiting facilities make less sense than lunar or asteroid based facilities where raw materials are located, but even those have lots of technical and financial challenges.
i understand that this kind of technology is no where near implementation, i am just saying that it is time that the human race gets started on it. i agree that infrastructure of this kind is decades off, but think of our highway system. it wasn't built in a year, it took several years. i just think that keeping a strong presence in space will require infrastructure in place, and that takes a long time. we should get started on it now, so when we do need it, it is available.
i don't think a mining drone bound for asteroids is beyond the scope of our technology. we already send unmanned missions to further places in our solar system, and they are largely automated in most cases. i like the idea of mining asteroids because they are a good source for raw metals, water, and o2.
i think that you're ignoring the substantial momentum change that's required to get a serious chunk of asteroid down to earth orbit. that fuel would need to moved all the way from earth to the asteroid orbit. note that most asteroids are not rich in aluminum nor titanium, so prospecting for these materials will be none trivial and will cost a considerable amount of fuel just to do the prospecting. then, we need to get rid of the smelting waste, so again, a truckload of fuel is required to deorbit the waste material. the minimum fuel trajectories take something like 10 times longer to do the trip, so we'd be talking about stretching the basic fabrication process out by decades, otherwise we'd need a massive amount of fuel.
even though the iss took nearly 20 years to design, it went through something like 4 major design iterations, but in each iteration, the precise design solution was ostensibly known. at this time, none of the critical design solutions are known, since we have no idea how to deal with the propulsion. how are we going to get the major infrastructure into orbit? building the iss required some serious machinery to do just the metal forming and shaping, ignoring the smelting, etc.
until we have solid solution with dealing with moving crap around the solar system without getting fuel from earth, we don't have a viable design concept. until we have a approach to get the large fixtures and machinery needed to do the basic forming and shaping of structures, we don't have a viable design concept.
ttfn
irstuff, star sir. i was thinking exactly the same about the energy needed for the momentum change to effectively change the orbit for the mining spacecraft and its load. however it's been a while since my orbital mechanics lectures and i didn't want to jump the gun.
kenat, probably the least qualified checker you'll ever meet...
personally, i'd put a couple of technological developments ahead of orbiting manufacturing facilities ...
fusion powerplant
space elevator
(world peace is too much to hope for)
yeah, or barring the space elevator at least a cheaper, safer way to routinely get into orbit (that doesn't turn said orbit into a virtual mine field of space debris).
some kind of hybrid between what scaled composites did with white knight/space ship one and how the asat was launched by an f-15 in a zoom climb

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