Humanity's Biggest Machines Will Be Built in Space (popularmechanics.com)

No gain until we get primary materia from space by Eloking · 2018-02-19 03:12 · Score: 3, Insightful

I fail to see what's the gain between launching a rocket with 1 ton of preassembled componned or 1 ton of materia used by a space 3D printer to build those component. And unless there's 0% loss during the 3D printer process, I would even say it's less efficient that way.

The only way I can see a real gain is if most of the materia weight come directly from space. For instance, asteriod mining.

--
Elok

Re:No gain until we get primary materia from space by Anonymous Coward · 2018-02-19 03:22 · Score: 1

There are some designs that cannot be cut into 1-ton preassmbled components. The added utility of using such a design would have to exceed the losses in utlizing the Enormous Space Printer!(TM) if we want a net gain in efficiency.
The other side of this is that some steps in expanding infrastructure will always look silly if evaluated on their own merits instead of the longer goal that includes many more stages. If no one is willing to prospect asteroids until there is a facility to send the materials to, then a facility is the next critical step.
Re:No gain until we get primary materia from space by Rei · 2018-02-19 03:28 · Score: 1

They're arguing that you're not limited by fairing sizes if you build in space, which is true. But then again, there's lots of ways to get around fairing size limitations. Here's one of my favourites: rollable composite trusses. You can even have wiring, plumbing, flexible solar, etc rolled up with it. There's also self-deploying booms, retractable booms, etc. Whatever you have all is stored flat during launch, no thicker than the material's outer wall.

--
Point of interest. Offering to shoot us might not work so well as an incentive as you might imagine.
Re:No gain until we get primary materia from space by AndroSyn · 2018-02-19 03:36 · Score: 4, Insightful

I fail to see what's the gain between launching a rocket with 1 ton of preassembled componned or 1 ton of materia used by a space 3D printer to build those component.
Think along the lines of large objects that could not be launched from Earth pre-assembled, especially items that have large empty spaces inside of them.
Also. you can assemble some items in space that would collapse under normal Earth gravity. Building in space, means that the object only needs to be able to stay together in micro-gravity, which gives you a bit more freedom in structural designs.

The only way I can see a real gain is if most of the materia weight come directly from space. For instance, asteriod mining.
The current problem with mining materials in space is, we simply do not have the infrastructure in place to mine, purify and process minerals into finished metals in space. Sure it would be nice to see this some day, but in the mean time it's cheaper to launch your raw materials off Earth, especially if they're in the form of powdered metals, those pack very nicely into rockets. Besides I've heard there is some weird South African guy selling used discount rockets, not sure I'd trust him with my life, but with a pile of titanium powder, sure.
In short, you need to build the salt box pioneer shack in space before you build the steel furnace in space. We're barely past the salt box shack stage.
Re:No gain until we get primary materia from space by LifesABeach · 2018-02-19 03:37 · Score: 1

Another problem that happens all to often is the improvement of knowledge. But those improvements can not be transferred to a space design for logistical reasons. If designs are able to be improved while waiting to be manufactured in space, then a better solution can be achieved.
Re:No gain until we get primary materia from space by amiga3D · 2018-02-19 03:39 · Score: 2

They're talking about size. 100,000 tons of material can be sent in multiple launches but a 100,000 ton machine is too big to send. Of course at 10,000 dollars per pound it's too expensive to send too at current costs to send a payload into orbit. Of course they're working on that. Most Sci-Fi authors envision using asteroids to mine for materials instead of boosting it out of a gravity well. Maybe my great grand children will live to see it.
Re:No gain until we get primary materia from space by Immerman · 2018-02-19 03:45 · Score: 2

But as you say, not all improvements can be transferred to space. And perhaps far more significantly, a great deal of improvements for space can't be transferred to (or fully developed on) Earth. We've got to actually get out there and start experimenting, see how the theory translates to practice, and have ongoing incentive to improve freefall industrial techniques in order to see the sorts of advances we've seen on Earth.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:No gain until we get primary materia from space by Anonymous Coward · 2018-02-19 04:00 · Score: 1

Because, like TFA says, you can build things out there that couldn't even support their own weight on earth - that opens the possibility of radical designs that might limit the usefulness of pre-assembled parts. It's an optimization problem with different trade-offs depending on what the capabilities and inefficiencies are of building things in space versus building things planet-side and launching them. For instance, I could imagine that building a giant antenna or solar array would likely benefit from using both approaches.
Re:No gain until we get primary materia from space by Immerman · 2018-02-19 04:01 · Score: 1, Troll

>we simply do not have the infrastructure in place to mine, purify and process minerals into finished metals in space
We may not need to. There's considerable evidence to suggest that there's plenty of asteroids out there that are nearly pure iron - as in all we have to do is chop it up, hammer it out, or melt it down and cast/print with it. In fact, there was some research recently suggesting that most, if not all, pre iron-age iron tools were made from meteoric iron. Unlike earth-based iron deposits that are all oxides and other iron-bearing minerals, iron meteorites were already fairly pure refined metal: oxidation is primarily an planetary phenomena - you mostly need liquid water or free oxygen to convert iron into non-metallic minerals, and you don't get those in vacuum.
Yeah, such rough-and-ready construction wouldn't benefit from modern advances in alloy technologies - but even cast, rolled, etc. iron is pretty useful stuff, especially in an environment where there's no gravity to resist. Similarly, there's lots of rocky asteroids out there that should provide copious raw filler material for "concretes" of various sorts, which have great potential as radiation shielding. Even if 10% of the material is some sort of vacuum-hardening epoxy bonding agent made on Earth, you can still get 90% of your material from space.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:No gain until we get primary materia from space by Zocalo · 2018-02-19 04:06 · Score: 1

There's a lot that can be done by launching components that are then bolted to gether in orbit, or having flat-pack components that are expanded in situ - we built the ISS that way, afterall. I guess what they're trying to get across here is what we might be able to accomplish if the current fairing limitation were to be removed - applications that might *require* a solid 100m long truss rather than an oversized shower curtain rail, for instance. The pictures of Musk's Tesla in the Falcon 9 Heavy showed a lot of room around the car, but it's still a pretty tight space in there compared to some of the current structures we build on Earth as single pieces to achieve the necessary structural strength. Assuming this 3D printer can provide all the necessary strength and durability given suitable input material, perhaps this is how we'll create the components for the kind of space stations and other orbital structures that you typically see in SciFi but would currently be impossible to create, even if we could get that much mass into orbit.

--
UNIX? They're not even circumcised! Savages!
Re:No gain until we get primary materia from space by Anonymous Coward · 2018-02-19 05:10 · Score: 1

The key part for TFS is:-
"We can manufacture a structure that couldn't support its own mass if it were on Earth"
In such a case, it couldn't be preassembled on Earth as it would collapse.
Re:No gain until we get primary materia from space by drewsup · 2018-02-19 05:30 · Score: 2

structures that would not survive launch G's would be the obvious answer. You can 3D print something that is 80% empty that is perfectly acceptable as a beam or truss for space construction.
Re:No gain until we get primary materia from space by Gr8Apes · 2018-02-19 05:35 · Score: 2

So you have a spacestation, or 1 ton of material. Which is going to fit on top of your rocket?

--
The cesspool just got a check and balance.
Re:No gain until we get primary materia from space by UnknowingFool · 2018-02-19 06:09 · Score: 1

I fail to see what's the gain between launching a rocket with 1 ton of preassembled componned or 1 ton of materia used by a space 3D printer to build those component.
The major gain is self sufficiency. What is the current process today if a part breaks on a station like the ISS? The best case scenario is that there is a spare part already on the station and that it can be replaced right away. However, the station doesn't keep a spare of every single part and they have to wait until the next launch to replace it. That could be a minor inconvenience or a major problem depending what part needs to be replaced.
The second gain is that some parts can be fabricated that are too large to be pre-assembled. Many components are limited by size that can be sent up without being folded or compacted somehow. That is currently is a major limitation of what can be sent in space in that payloads must not only be under a certain weight by also volume so that the payload fits.

--
Well, there's spam egg sausage and spam, that's not got much spam in it.
Re:No gain until we get primary materia from space by UnknowingFool · 2018-02-19 06:17 · Score: 1

There's considerable evidence to suggest that there's plenty of asteroids out there that are nearly pure iron - as in all we have to do is chop it up, hammer it out, or melt it down and cast/print with it.

And how do you propose to do that in a zero G environment? All those processes here on Earth depend on gravity. If you try to "chop" or "hammer" something in space, it doesn't work given Newton's laws of motions . Melting ore on Earth specifically requires separation of impurities to "float" to the top of the smelt based on densities. Casting requires pouring melt into a cast using gravity, etc.

--
Well, there's spam egg sausage and spam, that's not got much spam in it.
Re:No gain until we get primary materia from space by claar · 2018-02-19 06:26 · Score: 1

Some people think SpaceX's BFR may get costs to LEO down to $10/kg.
If my math works out, that gets your 100,000 tons of material in LEO for $900 million (transport costs only). Using BFR's estimated 165 tons/launch to LEO, that's about 600 trips.

--
I'd give my right arm to be ambidextrous...
Re:No gain until we get primary materia from space by rickyslashdot · 2018-02-19 06:27 · Score: 1

Actually, the CHEAPEST and best long-term supply of base-materials is from the moon . . . using a mass-driver system (electric driven from solar power) to deliver as much material as needed ANYWHERE in the earth-moon system.

--
redneck geek
Re:No gain until we get primary materia from space by Applehu+Akbar · 2018-02-19 06:36 · Score: 1

...having flat-pack components that are expanded in situ
This will be a great human factors test: If astronauts can assemble structures in orbit from Ikea instructions, we are assured they will stay sane during a long voyage to Mars.
Re:No gain until we get primary materia from space by ceoyoyo · 2018-02-19 06:41 · Score: 1

The James Webb telescope isn't much bigger than the 1948 Hale telescope. One of the things that makes it remarkable (and expensive) is that it folds up small enough to fit in a fairing for launch. If you could build one in space from raw materials you could make it enormous.
Living volume in space is pretty cheap in terms of materials. So why is it so cramped in the ISS? Because all those modules had to fit into fairings for launch. There are proposals to manufacture enormous stations in orbit basically welding together boxes made of girders manufactured in space.
If you could source the material in space as well, then you could build *really* enormous things. With space-based manufacture and raw material you could probably make things like O'Neil cylinders and orbital rings without much trouble.
Re:No gain until we get primary materia from space by lars5 · 2018-02-19 07:05 · Score: 1

"...or having flat-pack components that are expanded in situ..."
So the future of the space program is to be more like Ikea?
*ducks*

--
Don't Panic.
Re:No gain until we get primary materia from space by lars5 · 2018-02-19 07:07 · Score: 1

Ya beat me to it, and by quite a while.
That's what I get for not refreshing before posting.

--
Don't Panic.
Re:No gain until we get primary materia from space by lars5 · 2018-02-19 07:14 · Score: 1

"...If you try to "chop" or "hammer" something in space, it doesn't work given Newton's laws of motions..."
False.
All you have to do is use diametrically opposed chopping or hammering forces in a closed-system framework.

--
Don't Panic.
Re:No gain until we get primary materia from space by AvitarX · 2018-02-19 08:59 · Score: 2

Anything built on earth needs to be able to cope with 9.8m/s^2 acceleration.
Their premise is that building in space allows for sparser construction.
You may be able to reduce the overall amount shipped from Earth to space and save money overall (not saying it will work, but that seems to be their premise).

--
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Re:No gain until we get primary materia from space by Immerman · 2018-02-19 10:34 · Score: 1

Of course it still works - nothing has changed except that you can't rely on gravity to hold your feet to the ground. We don't have decent gecko-grip boots yet, but there's plenty of cruder solutions. And for heavier work: power hammers and wood splitters have their own integrated anvils, it's not a complicated concept to adapt. Similarly, if you want to apply forces against an asteroid, you just have to fasten yourself to the ground first so that you don't just push yourself away instead.
Rule of thumb: if you can figure out how to do something upside down or sideways, zero G won't be a problem.
Injection molding doesn't care about gravity, but if you really want to do an open-pour casting, centrifuges are really easy to make in space - all you need is a spinning tether with cages on the ends. And they already use them here on Earth all the time for castings where gravity just doesn't supply as much force as they'd like.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:No gain until we get primary materia from space by drinkypoo · 2018-02-19 13:50 · Score: 1

And how do you propose to do that in a zero G environment? All those processes here on Earth depend on gravity.
What? Who told you that? You're off your nut. For example, the commonest way to cut large pieces of metal for industrial purposes today is the band saw. That in no way requires gravity. Even when the systems currently use gravity, there's no reason why they have to. For example, a hydraulic system might use gravity on earth to settle the contents of a return tank. But in space, you might use a low-pressure accumulator in place of the tank, to force the fluid into the pump inlet. Industrial hammering processes use far more force than is provided by gravity; they are done with steam, or hydraulic force. Gravity is old hat, nobody has time to wait for hammers to fall.

--
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Re:No gain until we get primary materia from space by AndroSyn · 2018-02-20 04:28 · Score: 1

We may not need to. There's considerable evidence to suggest that there's plenty of asteroids out there that are nearly pure iron - as in all we have to do is chop it up, hammer it out, or melt it down and cast/print with it.
This presumes that you want to make EVERYTHING out of iron, and not steel(which needs further processing, you know). I'm not even sure if most of our modern steelmaking techniques would work in zero-g. Pure iron on its own isn't really all that useful, generally its too brittle without being alloyed with something else, like carbon.
It also doesn't help with other alloys that are quite likely to be more useful in space, aluminum, titanium, etc are all pretty useful. Not to mention PLASTICS! Pretty sure we're not going to mine the raw materials plastic in space either. There are just too many useful materials here on Earth that can't be sourced from space, some possibly never.
Re:No gain until we get primary materia from space by DarthVain · 2018-02-20 07:34 · Score: 1

Pretty much this. Stupid idea other than as a partial proof of concept in vacuum. Mass is mass.
Though I suppose if the 3D printer were designed in such a way as to use a dense mass as material, then inject gas to create essentially foam extrusions of such dimensions it would be unwieldy to launch. Anyway you'd still have to get the gas up there as there is literally nothing to work with.
Now if you could get a 3D printer to the moon, that is able to mine material, convert it to usable printing material, and then print things, and some robots able to move things around, well then you might have something... Again, a lot of missing pieces to that puzzle. However if seeing if you can reliably operate a 3D printer in vacuum (and gravity might be a bit odd to calibrate) is a first step, then it might be worth the efforty
Re:No gain until we get primary materia from space by Shotgun · 2018-02-20 09:52 · Score: 1

The machine is in a VACUUM already. Build anything you want with vacuum casting. All that is necessary is to boil the metal and then spray it into whatever shape makes you happy. Sunlight, collected by mirrors and then focused onto a tiny spot would easily boil off the metal, then magnets would create a virtual "nozzle" to deposit it with micrometer precision.

--
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Re:No gain until we get primary materia from space by Immerman · 2018-02-20 14:51 · Score: 1

Not at all. All it assumes is that making things out of iron would be useful. More sophisticated alloys and manufacturing techniques would undoubtedly be developed too - but we have to start somewhere, and iron is an incredibly useful material just as it is, and far easier to work with when we're just starting out.
As we expand into space, it makes sense to pick the low-hanging fruit first. Bulk construction using iron, radiation shielding using "cemented" dust and gravel, and rocket fuel from water - the technologies for all three are reasonably straightforward, and they address the most mass-intensive demands for developing infrastructure in space.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:No gain until we get primary materia from space by painandgreed · 2018-02-21 04:49 · Score: 1

And how do you propose to do that in a zero G environment? All those processes here on Earth depend on gravity. If you try to "chop" or "hammer" something in space, it doesn't work given Newton's laws of motions . Melting ore on Earth specifically requires separation of impurities to "float" to the top of the smelt based on densities. Casting requires pouring melt into a cast using gravity, etc.
As far as chopping up, there are multiple ways it might be done. Centrifugal force or held in place by blowers as incarcerating said asteroid inside a structure would probably be a requirement, although they might just attach a hard point to place such digging equipment on the item to be worked into smaller bits itself. Still, most ideas go more towards the smelting process which the leading proponent is the Mond process where using heated carbon dioxide can turn nickel and iron (IIRC) into gasses at various temperatures that can be collected at points by heating or cooling said gas leaning the much reduced core of other elements to be dealt with. Other processes for non-iron/nickel asteroids, of course, but ice once could just be heated and outgassed in a similar fashion. Its more complicated than that, but that'll give you an idea of where to start if you are interesting in investigating the possible technologies for mining asteroids in space.
Re:No gain until we get primary materia from space by UnknowingFool · 2018-02-21 06:31 · Score: 1

What? Who told you that? You're off your nut. For example, the commonest way to cut large pieces of metal for industrial purposes today is the band saw.
Where in my post did I say anything about the most common way to cut metal. What I did say specifically is that in processing ore as the OP said "chop it up, hammer it out, or melt it down and cast/print with it" here on Earth requires gravity. Please show how none of those processes on Earth depends on gravity.

That in no way requires gravity. Even when the systems currently use gravity, there's no reason why they have to. For example, a hydraulic system might use gravity on earth to settle the contents of a return tank
A hydraulic system that handles molten metals. Sure that's very practical in zero G.

But in space, you might use a low-pressure accumulator in place of the tank, to force the fluid into the pump inlet.
Again for fluids at room temperature it's not a problem. We are talking about molten metals here.

. Industrial hammering processes use far more force than is provided by gravity; they are done with steam, or hydraulic force. Gravity is old hat, nobody has time to wait for hammers to fall.
How would hydraulics work in space especially with something like steam? There's a reason the ISS does not use steam power to drive any processes.

--
Well, there's spam egg sausage and spam, that's not got much spam in it.
Re:No gain until we get primary materia from space by UnknowingFool · 2018-02-21 06:54 · Score: 1

The Mond process relies on putting impure nickel through with heated carbon monoxide gas. Nickel tetra carbonyl becomes a liquid not a gas. Then the liquid is further heated to separate CO from Nickel. Heating a liquid is easy on Earth as you heat the bottom of the vessel. How do you heat a liquid/gas mixture in zero G? A possible way of doing it is to cool the liquid to 1F, extract the solid then heat the solid. However that requires a lot more steps and energy. Would it be practical energy wise?

--
Well, there's spam egg sausage and spam, that's not got much spam in it.
Re:No gain until we get primary materia from space by UnknowingFool · 2018-02-21 07:20 · Score: 1

All that is necessary is to boil the metal and then spray it into whatever shape makes you happy.
The problem is not that you can't heat ore. The problem with processing ore is separating out the impurities. In the exact example, chopping, hammering, smelting are ways here on Earth to remove impurities from metals like iron. They rely on the fact that gravity is assumed. Can you devise other processes which do they same thing but do not rely on gravity, yes. But you can't rely on those processes.

--
Well, there's spam egg sausage and spam, that's not got much spam in it.
Re:No gain until we get primary materia from space by painandgreed · 2018-02-21 12:10 · Score: 1

That's right. been a while since I've looked into it. Energy practicality depends on how solar panels are looking in that time frame. ( Perhaps 50-100 years for testing prototype systems if we're lucky by my reckoning. ) If construction of a suitable window is possible, just direct sunlight concentration by a mirror array. My thinking was the target is contained, floating in the middle, kept in place by several possible methods, and first outgassed by heating it up. Then Mond process forms the liquid witch will hopefully float in a pool held together by surface tension and kept in place by directed gas flow, and then the CO is thermally separated via probes where the nickel deposits on the end. I think there is a similar vapor deposition method for Iron pentacarbonyl. Then, hopefully, you're left with the remains that can be handled in other manner.
Or you just have a slowly rotating processing plant to simulate gravity.
Anyway, that's was my first pass through via gedankenexperiment.

the future, just the same as the past by nimbius · 2018-02-19 03:13 · Score: 1

current build practice: *drop my 10mm socket and watch it roll down the driveway* oh...crap.
future space build practice: *drop my 10mm socket and watch it assume a decay orbit toward Scotland* oh....*booop*....crap....*boooop*

--
Good people go to bed earlier.

Re:the future, just the same as the past by Immerman · 2018-02-19 04:09 · Score: 2

Nope. Drop your socket, and it slowly starts do drift away from where you let it go. As long as you don't actually throw it away from you, it will remain nearby for quite some time. And since you can't throw fast enough to appreciably change its orbit, the only way it's on a decay orbit to Scotland is if you were already on that path yourself.
Heck, it doesn't even have any differential in gravitational acceleration to power it's rolling underneath to the exact center of your space-car like it inevitably would here on Earth. And if it somehow manages the feat anyway - well, there's no ground underneath it to make it difficult to get to (which would probably dramatically reduce the odds of it happening in the first place).

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:the future, just the same as the past by rickyslashdot · 2018-02-19 06:34 · Score: 1

WORSE CASE - drop my 10mm socket . . . and watch it return in a couple of years in a drift/altered gravitational differential, magnetic bias, solar wind offset, etc.) orbit at 10K(+) MPH to blow through my habitat like a micro-nuke ! ! !

--
redneck geek
Re:the future, just the same as the past by Immerman · 2018-02-19 10:40 · Score: 1

Nope, but a good impact wrench already does a better job anyway. Just need to make sure you fasten yourself to the car first, so that it doesn't just send you spinning instead. Gravity is really convenient, but it's not irreplaceable.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.

Re: No gain until we get primary materia from spac by Anonymous Coward · 2018-02-19 03:31 · Score: 1

My guess would be that the raw materials would be lifted to space in a far more efficient way. When the payload is rock and sand you can send it with a bigger boom.

Re:Planetary Dyson Sphere by Hal_Porter · 2018-02-19 03:36 · Score: 1

This would also be a good way to control how much radiation from the Sun reaches Earth's surface.

If you really need to that quickly and cheaply sulphate aerosols seem like a very promising option.

https://www.ted.com/talks/david_keith_s_surprising_ideas_on_climate_change

--
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;

Our Greatest Achievements by LifesABeach · 2018-02-19 03:42 · Score: 1

Will involve space, and helping each other.

Re:Great! by Anonymous Coward · 2018-02-19 03:51 · Score: 1

Space is big, dude. Do you know how many paperclips you can make out there?

Makes sense by 110010001000 · 2018-02-19 04:09 · Score: 3, Funny

It makes total sense. It is always easier to build things in space. Just like living on Mars. It is so much easier than living on Earth. And now we have AI which makes it even easier.

Re:Makes sense by jwhyche · 2018-02-19 05:08 · Score: 2

No duh. Where are we going to build our first dyson sphere? In the middle of Kansas?

--
I read at +2. If your post doesn't reach that level I will not see or respond to it.
Re:Makes sense by swillden · 2018-02-19 19:33 · Score: 2

It is always easier to build things in space.
Obviously not. But, at some point it will become easier to build some things in space, especially things that can't be built in a gravity well at all. Automated orbital factories are a long way off, but an orbiting 3D printer is a big first step down that long road.

Just like living on Mars. It is so much easier than living on Earth.
Now you're just making shit up. No one with half a brain has ever made that claim.

And now we have AI which makes it even easier.
The sort of AI we have now probably does make some things easier, though I don't claim to know what. The sort of AI we will eventually build will definitely make things easier.
Your entire premise seems to be that what we know how to do now is approximately all we'll ever know how to do. You should really rethink that.

--
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.

Re:Planetary Dyson Sphere by 110010001000 · 2018-02-19 04:09 · Score: 1

It would be even easier if you added blockchain to AI, robotics and 3D printers. We could have it done in a decade (tops).

1) Build 3D printer, 2)..., 3) Profit! by sjbe · 2018-02-19 04:17 · Score: 1

When rockets can no longer hold oversize payloads, building in space might be the best way to go.

Naturally but kind of skipping an important step there. You also have to be able to supply materials in space including raw materials and the production equipment and the power source(s). Whether shipped from earth or mined from other planets/asteroids, you don't get to skip the step of having rockets deliver the machines and power source and the materials to be able to manufacture in space. It's going to be a lot more complicated than shipping even a very clever 3D printer. Actual assembly work is the "easy" bit.

Nearly everyone who has fanciful ideas about manufacturing and mining in space overlooks the supply chain problem. You cannot do useful manufacturing until you have a supply chain established which here on earth we tend to take for granted. Want to build a truss in space? Great. You at minimum need machine(s) that can make it, the tooling for that machine, material handling equipment to move everything around, a source of the right type of metal and other materials in a form factor usable for production, and a power supply. And those are just the broad categories each of which has a bill of materials a mile long of stuff that has to be made and delivered to the production site. 3D printers can mitigate some of the problems but far more remain. And it's going to be VERY expensive to build the supply chain and it's likely to take a very long time.

Don't get me wrong I'm all for manufacturing in space but it's going to be a LOT more complicated than shipping up a 3D printer and some powdered metal and/or plastic. I'm very glad to see people working seriously on the problem but it's going to be decades under the best of circumstances before we see space based manufacturing as more than a research project. There simply isn't enough funding currently to build meaningful off planet infrastructure for manufacturing any time soon.

Re:1) Build 3D printer, 2)..., 3) Profit! by 110010001000 · 2018-02-19 04:20 · Score: 1

No. We will just mine asteroids (in space). Next.
Re:1) Build 3D printer, 2)..., 3) Profit! by Zocalo · 2018-02-19 04:50 · Score: 1

Or they're just working on one part of the overall problem - the printer. How it gets supplied with raw material is another issue for someone else to solve, but there are multiple options there. You could ship the stuff direct from Earth (expensive but doable - crawling), mine it in place (potentially viable for the moon, Mars, or maybe an asteroid - walking), or mine it in space and ship it to the printer (probably a long way off but already being explored - running). As with the printer, the problem of supplying the raw material is a matter of one step at a time. Yes, it'll take a lot of time and expense before we get to the running phase, let alone see the fruits of it, but you could say that about a lot of things we now take for granted because someone persevered with their part of the problem and relied on others to sort out the rest.

--
UNIX? They're not even circumcised! Savages!
Re:1) Build 3D printer, 2)..., 3) Profit! by sjbe · 2018-02-19 05:01 · Score: 1

Or they're just working on one part of the overall problem - the printer.

Which is fine but then don't give me a bunch of ridiculous PR about building giant structures in space when that isn't likely to happen within the lifetime of anyone reading this. Just say they are working on 3D printers in space which is sufficiently cool by itself.

How it gets supplied with raw material is another issue for someone else to solve, but there are multiple options there.
No there are not. There is precisely one option currently and for the reasonably foreseeable future which is to supply from Earth via rockets. The notion of mining resources that didn't come from Earth simply isn't going to happen for many decades to come even under the most optimistic of assumptions. I'd love to see it happen but I don't honestly expect to see it before I die. Maybe a few research projects and some clever automation to take the first early steps. There isn't enough funding right now to rationally expect more than that.

you could say that about a lot of things we now take for granted because someone persevered with their part of the problem and relied on others to sort out the rest.
Persevered for centuries. It literally took centuries for our technology to get where it is. There is no rational reason to believe it will not take more centuries to get to the point where space based manufacturing is economically viable. It's a worthy goal but the destination is a long way away without a clear path to get there.
Re:1) Build 3D printer, 2)..., 3) Profit! by crypticedge · 2018-02-19 06:05 · Score: 1

The notion of mining resources that didn't come from Earth simply isn't going to happen for many decades to come even under the most optimistic of assumptions. I'd love to see it happen but I don't honestly expect to see it before I die.
People said the same thing about putting people on the moon in the years prior.
They were wrong then too.
Re:1) Build 3D printer, 2)..., 3) Profit! by Zocalo · 2018-02-19 06:20 · Score: 1

I didn't say the options where there now; I posited that they might be when the development of the printer technology is ready for them - crawl first, then walk, then run. Currently we're crawling, but walking - using the printer on a Lunar or Martian construction - might not be so far off, especially if the construction process is handled by robots, which seems a logical first step for the initial setup of a potential inhabited base before the humans might arrive.

Persevered for centuries. It literally took centuries for our technology to get where it is.
For some things, sure, but the overall pace of progress pretty much across the board has sped up immensely over the last hundred years or so. Take nautical ships; centuries of limited change based around wooden keels and hulls, then massive progress since the advent of metal hulls and steam power, or aerospace; decades to go from puddle hopping flights to routine intercontinental and tentative spaceflight, then a similar timescale to get from there to where we are now with probes on the fringes of the solar system, roaming around the surface of other planets, and people actually living in space (only LEO, but still). Perhaps it will take a few centuries to get there but, quite frankly, given the huge potential commerical payoff and drive of companies like SpaceX, I wouldn't be at all surprised to see at least some of this kind of stuff bearing fruit somewhat quicker than that. Even optimistically I do think we're still talking decades though, but I'd say that the walking phase (3D printing for construction on the Moon or Mars) might potentially be achievable within the lifespan of people alive today.

--
UNIX? They're not even circumcised! Savages!
Re:1) Build 3D printer, 2)..., 3) Profit! by ceoyoyo · 2018-02-19 06:56 · Score: 1

"Persevered for centuries. It literally took centuries for our technology to get where it is. There is no rational reason to believe it will not take more centuries to get to the point where space based manufacturing is economically viable."
Yes, there is. Technology development has been exponential, not linear.
In terms of mining in space, you don't even really need to invent that much. There are some engineering problems to work out, but nothing that really looks like it would be terribly difficult. It requires some initial investment to bootstrap, but even that isn't really that big by modern engineering project standards.
The problem is that there's currently very little reason to do it. You'd certainly sell some mega-telescopes, and a few other things, but that's not going to fund an entire industry. However, if launch costs came down enough so that the space-based population could grow to a reasonable size, then you'd have a market, and industrial development would be pretty much automatic. Alternately, you could develop the industry to build things like orbital rings that would bring "launch" costs down, but that requires more up-front capital.
Some people think SpaceX might bring launch costs down to the magic threshold with the BFR. Personally, I think bootstrapping orbital industry is a good next project for NASA. Quit fiddling with Mars and bootstrap building material production on the moon with the goals constructing a lunar space elevator / orbital ring complex for practice, followed by an Earth elevator/ring.
Re:1) Build 3D printer, 2)..., 3) Profit! by rickyslashdot · 2018-02-19 07:34 · Score: 1

Seems like I'm always talking to the deaf, but GO TO THE MOON - LOTS of silicon ===> LOTS of solar cells ===> LOTS of power.
A basic rail/mass-driver can deliver any amount of raw materials (or even REFINED materials) anywhere in the earth/moon system (and BEYOND). The most rudimentary crude AI-driven scoop/heat/refine machinery can be turned into a quasi-von neuman solar cell factory - - - placing power-generating panels end-to-end, side-by-side, EVERYWHERE, and providing the energy needed to power a mass-driver to deliver materials into space at - essentially - NO COST, after the solar panels are in place.
PRIMARY ISSUE ===> put a crusher/scoop/refinery mini-bot on the surface, let it make solar cells, and WAIT. After the power is available, specialty metal/material refining and orbital injection become trivial issues. OK, so it only works for 14 days out of 28 - - - it still WORKS FOR FREE - driven by SOLAR ENERGY, just wait and let it do the job under AI-automation. Hell, if you want 24/7 operation, put a SECOND system on the other side of the moon - - - each working 14 days out of 28, so you have continuous production/operation.
Additionally, even though the poly-silicon solar cells aren't top-notch efficient, just MAKE MORE - - - there's a LOT of silicon, and a LOT of room, and all it takes is the initial investment to get the scoop-miners/refiners (mirror-ovens for heat/processing)/solar-cell building mini-bots ON THE MOON ! ! ! ! ! !
There's also lots of aluminum in the crust, so the metal framework, rails, and electrical wiring are all no-brainers. Most people believe that iron is needed for it's magnetic properties so the electrical-driven mass-driver can work.. However, aluminum wiring can be used to make electromagnetically-linked coils (like a transformer or electromagnet) around the mass-driver buckets to accomplish the same task.

--
redneck geek
Re:1) Build 3D printer, 2)..., 3) Profit! by ceoyoyo · 2018-02-19 13:05 · Score: 1

There's just as much iron in regolith as there is aluminum, so you get iron too. And also loads of magnesium, which is itself a pretty useful material.
Re:1) Build 3D printer, 2)..., 3) Profit! by RockDoctor · 2018-03-04 13:15 · Score: 1

constructing a lunar space elevator / orbital ring complex for practice, followed by an Earth elevator/ring.
Hmmm, I know that we currently have no materials or processes for making a material strong enough for an Earth "space elevator" - it would need something like a fibre with the tensile strength of diamond, in a really light high-strength epoxy. And we don't have a process for making diamond-strength fibre in millimetre lengths, let alone multi-kilometre lengths.
But a lunar "space elevator" - with about 1/6th of the gravity field (and IIRC, 1/80th of the mass) - that's a lot closer to actually being possible. Useless, but less impossible.
Hmmm, down side would be that the system would either need a large counterweight, or to reach a significant part of the distance from Moon to Earth.

--
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"

Re:10-1 by Anonymous Coward · 2018-02-19 04:44 · Score: 1

Or a giant bat-shaped structure that centers itself in front of a full moon.

Flexibility and cost by sjbe · 2018-02-19 04:47 · Score: 5, Insightful

I fail to see what's the gain between launching a rocket with 1 ton of preassembled componned or 1 ton of materia used by a space 3D printer to build those component.

The 3D printer doesn't require you to decide what to make with it prior to launch and it allows you to skip the delivery lead time for a product which could be substantial. Otherwise you are correct. You probably would need some sort of 3D printer like technology to manufacture a lot of stuff in space simply because a lot of the manufacturing techniques we use on earth simply wouldn't be viable due to supply chain issues and the need for compact and flexible production equipment.

The only way I can see a real gain is if most of the materia weight come directly from space. For instance, asteriod mining.

Asteroid mining is an idea that won't happen for a very long time. There are several huge obstacles to it including: 1) The fact that we don't have any mining or refining equipment that is space worthy nor any reasonable prospects of getting such equipment anytime soon. 2) The extravagant cost of getting the equipment (which again we don't have) to the asteroid and doing useful work with it. 3) Most useful products require multiple materials/components which cannot be sourced from a single asteroid even if it were financially viable to do so. For a long time to come it's going to be a lot cheaper to launch stuff from earth than to mine it from an asteroid.

Also the biggest obstacles actually are not material weight. We just haven't addressed the hard issues because it's SO expensive to get to orbit that they haven't been worth worrying about. But even if you drop cost to orbit to zero, the cost of building the technology and infrastructure to manufacture in space will likely dwarf even the current launch costs. Think of it this way. Ford builds cars and one of its assembly plants costs north of a billion dollars to create. That is just for final assembly. The cost of the production facilities and parts to build the product in its supply chain easily costs 100 times more than that (there are about 30,000 parts in a typical car). And we have proven and well developed sources of raw materials. All that to build a product we know how to make with proven technology we can manufacture with economies of scale. Making something the cost and complexity of cars in space at any sort of scale would cost a large fraction of the world GDP for the foreseeable future.

Space based manufacturing is arguably a worthwhile goal but we need to be realistic about how long it will take to make it economically viable.

Re:Flexibility and cost by Solandri · 2018-02-19 06:33 · Score: 2

The largest ship has a displacement (weight empty) of 100,000 tons. I'll ignore buildings since TFA is talking about machines. Current launch costs to LEO bottom out at about $4000/kg, though it could drop to $2000/kg in the near future (have to see if Falcon Heavy's costs hold up).

So getting enough materials into LEO to duplicate the largest machine currently built would cost (100,000 tons)*(1000 kg/ton)*($4000/kg) = $400 billion. Never mind the cost of fabrication and assembly.
Re:Flexibility and cost by ceoyoyo · 2018-02-19 12:56 · Score: 1

Why would you want to build cars in orbit? You'd start with structural materials. Likely that would involve scooping up lunar regolith and smelting it to make iron, aluminum and magnesium (and oxygen, which you want too). Electric bulldozers and solar smelters should work fine on the moon. You'd use those to make structural beams, hulls, whatever you can, shipping up everything else from Earth.
Re:Flexibility and cost by rahvin112 · 2018-02-19 16:42 · Score: 1

Space mining and ore processing has major advantageous over earth bound processing. The first is the ore's aren't all oxygenated from earth's atmosphere, this means iron can be found in its raw form rather than the iron oxide that exists on earth. One of the biggest challenges in processing ore on earth is getting all the oxygen out and getting back to the raw metal.
Another major advantage is that you can melt that ore with essentially a big magnifying glass and you have much longer to shape it because you don't' have air messing everything up.
There is one major problem though and that's the lack of gravity impeding molding and forming, something that could be addressed on the lunar surface or by building a big enough structure to make artificial gravity work. But overall mining and processing in space is probably easier than on earth and could be jumpstarted with a few tons from earth to setup the basics. The hard part is getting metal-rich asteroids into earth orbit, not the actual mining or processing. We're probably further along on this than people realize, I expect private space companies will make this happen long before a government could probably entirely for space tourism to begin with.
Re:Flexibility and cost by painandgreed · 2018-02-21 04:37 · Score: 1

The largest ship has a displacement (weight empty) of 100,000 tons. I'll ignore buildings since TFA is talking about machines. Current launch costs to LEO bottom out at about $4000/kg, though it could drop to $2000/kg in the near future (have to see if Falcon Heavy's costs hold up). So getting enough materials into LEO to duplicate the largest machine currently built would cost (100,000 tons)*(1000 kg/ton)*($4000/kg) = $400 billion. Never mind the cost of fabrication and assembly.
By my impression, when they mean largest machine, they are talking dimensionally rather than mass. They are talking about building a cube out of truss that is 5 kilometers to a side. Even adding diagonal crossbeams for support, it might only be a fraction of the mass of that ship.

Gravity, not Thermodynamics is the Problem by Anonymous Coward · 2018-02-19 04:55 · Score: 1

The laws of thermodynamics prevent this from happening.

No, they do not: they just require that the system to do build such a sphere expends energy. The rate of expenditure will determine how rapidly you can build the structure. something this large would require a huge amount of energy to construct but, if you are willing to let the process take long enough the actual power required can be small.

However, beyond the impracticality of construction on a human timescale with current technology a planetary dyson sphere is an absoutely appalling idea for the Earth because, as a sphere, it will be gravitationally decoupled from the Earth inside it. This means that its position relative to the Earth inside it will be completely unstable and the sphere will have to have it's position continually corrected to prevent it impacting the Earth. The power and fuel requirements to do this make such a project completely useless even if we had the technology required to provide the power and thrust required.

Re:Gravity, not Thermodynamics is the Problem by r1348 · 2018-02-19 08:48 · Score: 1

The ringworld is unstable!
Re:Gravity, not Thermodynamics is the Problem by dryeo · 2018-02-20 10:56 · Score: 1

We'll just retcon some thrusters and for good measure, a laser propulsion for the Sun, I mean Earth.

--
https://en.wikipedia.org/wiki/Inverted_totalitarianism

Re: Great! by dlleigh · 2018-02-19 05:09 · Score: 2

You don't want to build large structures in near Earth orbit anyway. Tidal forces would require substantially stronger structures than would be necessary farther from a gravity well. Also, even the small amount of atmospheric friction there would require you to periodically boost your structure back into a higher orbit, and the fuel cost for large structures would be prohibitive.

Re:Planetary Dyson Sphere by skids · 2018-02-19 05:14 · Score: 1

There are a LOT of potential energy sources in space that simply cannot be found and/or utilized on earth. Most are still out of our technical grasp, but solar isn't, and is pretty damn effective in space... even more so closer to the sun.

--
Someone had to do it.

Easy as pie by sjbe · 2018-02-19 05:19 · Score: 2

There's considerable evidence to suggest that there's plenty of asteroids out there that are nearly pure iron - as in all we have to do is chop it up, hammer it out, or melt it down and cast/print with it.

Oh is that all?

Do you have even the vaguest idea how hard and expensive what you just proposed actually is? What equipment do you plan to use? Because literally none exists or is even in development to do that. We don't have more than even the vaguest idea how we could possibly do industrial scale mining in the vacuum of space. We don't have the technology and won't for some time to come.

Even if 10% of the material is some sort of vacuum-hardening epoxy bonding agent made on Earth, you can still get 90% of your material from space.

Got any more made up statistics you'd like to cite?

Re:Easy as pie by Applehu+Akbar · 2018-02-19 06:39 · Score: 1

Got any more made up statistics you'd like to cite?
That you, in particular, will not be going out there. Musk and the Chinese have their own plans.
Re:Easy as pie by angel'o'sphere · 2018-02-19 08:34 · Score: 1

I guess the word 'technology' has a quite special meaning for you?
We don't have the technology and won't for some time to come.
Yes we have. Since decades, half a century minimum.
There is no 'special technology, that does not exist yet' needed to fly a small craft to an iron asteroid, capture it and mine the iron: it is just extremely time consuming and so expensive it is right now not worth the efford.
Thats all ...

--
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Re:Easy as pie by Immerman · 2018-02-19 14:29 · Score: 1

Nope, it certainly doesn't. And it will continue to not exist until people actually go try to make it - that's kind of the whole point of trying, isn't it? Nobody will ever develop micro-gravity mining or metallurgy processes here on Earth, they'd be completely useless.
As for doing anything on "industrial scale" - the solution is simple: we won't. Not at first. First we figure out how to do it, and then we figure out how to scale up. Just like we did with terrestrial technology. And that will be fine, because at first we won't have sufficient demand for anything to justify producing it at industrial scales - well, except for rocket fuel maybe.
And a great deal of terrestrial technology will translate with minimal adaptation: casting metal sheets may be a challenge (or not: centrifuges are easy to make in free fall), but I doubt your average roller mill actually depends on gravity for much of anything. Nor does a power-hammer have any special need of gravity. Nor a metal-stamping machine. There will be details where an assembly line will need to be adapted to the fact that gravity isn't a convenient adhesive and sorting tool, but a great deal of the processes could already be migrated with hardly any adaptations at all. Heck, we already have 3D printers that work just fine upside down - microgravity is much less of a challenge.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:Easy as pie by Shotgun · 2018-02-20 09:50 · Score: 1

Dude, free your mind. Rollers? Stampers? Molds? Pffft! Totally pointless. All of it.
The machine is in a VACUUM already. All that is necessary is to boil the metal and then spray it into whatever shape makes you happy. Sunlight, collected by mirrors and then focused onto a tiny spot would easily boil off the metal, then magnets would create a virtual "nozzle" to deposit it with micrometer precision.

--
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Re:Easy as pie by david_thornley · 2018-02-20 11:13 · Score: 1

No, we haven't had the tech since 1968. In 1968, we could not build an adequate robot miner, nor could we support a human in space that long. We're still trying to figure exactly how to send humans on long journeys outside Earth's magnetosphere, and even with that protection it's bad for the human. In 1968, we could have sent an object to an iron asteroid, and we could have gotten some data from it. That's about the limit.
There's also the question of what we do after we mine the iron to get it somewhere useful.

--
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Re:Easy as pie by Immerman · 2018-02-20 15:21 · Score: 1

It's easy enough to create an oxygen-free atmosphere here on Earth - and yet we don't work metal that way here either. Perhaps there's a good reason?
First I assume you mean *melting* the iron, rather than boiling it - trying to precisely work with a gas tends to be a laboratory exercise, not an industrial one. Moreover, gaseous iron isn't magnetic, in fact the first magnetic gas was only discovered in 2009, and it was lithium cooled to within a billionth of a degree of absolute zero. And actually, molten iron isn't magnetic either - metals pretty much all lose their magnetic properties well before they melt.
Molten iron is still paramagnetic though, so you could still manipulate it with sufficiently strong magnetic fields. No longer a simple task though, especially considering that whatever iron structure you're building *will* be magnetic, and thus react far more strongly to your magnetic "nozzle" than the molten "ink" does. Plus, if you're spraying liquid metal around it's going to be almost impossible to keep it from splashing, and thus building up on everything else in the area in a chaotic fashion, including your manufacturing equipment.
As for micrometer precision - I think you'd be greatly disappointed. Completely aside from the difficulties of creating such precision, you'd need an extremely narrow stream of metal for than kind of precision to even matter - which means your nozzle has to be very close to the target to keep the stream from solidifying long before it makes contact. Vacuum insulates you from conductive heat losses, but does nothing against radiant losses. So you're basically back to a boring 3D printer, and all the magnetic guidance stuff just introduces needless complexity.
And finally, even assuming all the other problems could be solved, there's one big honking one that probably wont be: material strength. All that hammering and crushing of iron isn't just to get it into a specific shape, it also imparts far greater strength than is present in the original, brittle, cast-iron stock. A very large percentage of the strength and durability of iron products is due to the internal molecular alignments created through working it. Even with today's high-end 3D metal printing, there's usually a final firing process designed to *almost* melt the structure so that the layers merge together at the molecular level, dramatically increasing strength. And even with that, you'd only be looking at solid-cast strength, at best. Worked strength is likely to be permanently out of reach of 3D printing.

--
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Re:Easy as pie by angel'o'sphere · 2018-02-21 11:55 · Score: 1

You aremicing up technology with limits.
If you can put a human into space and land him savely on the moon and bring him back you have that _technology_
Extending that to an 18 month trip is still simply the same technology.
And yes, if we wanted we had robot miners around 1968, we just did not build them that time. What exactly do you think is so compicated about them?

--
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.

Re: Great! by ShanghaiBill · 2018-02-19 05:23 · Score: 1

It's already a junkyard in near earth orbit.

We can clean up LEO with a laser broom.

Re:Planetary Dyson Sphere by ShanghaiBill · 2018-02-19 05:31 · Score: 4, Informative

Energy storage alone would eat up most of the bonus you get from zero-G.

Why would you need to store energy? The lack of atmosphere means the sun is twice as bright, and it doesn't set. There is no "night" in space.

As every Star Trek fan knows... by fieldstone · 2018-02-19 05:36 · Score: 1

Big space stations and starships would have to be built in space due to the gravitational benefits. That also would tend to leave them unable to land without massive damage entering the atmosphere, unless they are able to separate into distinct sections, one of which could have the necessary size and shielding.

To me, the real question is whether or not our species will destroy itself, or get stuck in a cyberpunk-style corporate dystopia, before getting a chance to create a society like the Federation.

Space catapult by WoodstockJeff · 2018-02-19 06:32 · Score: 1

One of the big arguments against the use of a rail-gun like space catapult is that cargo and humans would not survive the acceleration needed. Raw materials, on the other hand, could.

Just how far can you chuck a pumpkin?

Space Elevator by atomicalgebra · 2018-02-19 07:24 · Score: 2

Constructing a space elevator would make it significantly cheaper to reach space. There are a lot of technical problems that we have to solve first such as how to mass produce carbon nanotubes in space, but the benefits would be enormous.

Re:Planetary Dyson Sphere by angel'o'sphere · 2018-02-19 08:53 · Score: 1

You are aware that 'the laws of thermodynamics' are to describe steam engines and other heat machines and have no application in space travel?
The rest of your post is completely bollocks ...

--
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.

Use the moon for materials. by az-saguaro · 2018-02-19 10:20 · Score: 1

On smaller scale projects in earth orbit, the raw materials could be rocketed and orbited to the manufacturing site as we do now. Sooner or later though, the cost of hoisting large megastructure masses to orbit could be prohibitive. If the raw materials were to come from space, then asteroid mining is a hypothetical idea, but it seems to me to have too many practical and economical limitations in this nascent concept stage. So, what about the moon? Here is a vision for the not too distant future.

Whatever the raw materials might be, lifting them out of lunar gravity to earth capture should be relatively cheap or on par with lifting to earth orbit. So, we set up lunar bases, meant to prospect for useful mineral deposits, then start mining. Like any new colony, buildings and infrastructure need a bootstrap process and period of time to ramp up to capacity. But, put a few essential pieces of machinery up there to start with, to extract and process some pioneer metals and materials, then use printers to build more machinery. Take advantage of no atmosphere and lots of sunlight to power the mining, milling, smelting, and manufacturing operations. Furthermore, use that same energy abundance to create or power electric propulsion systems or mass drivers to pop the processed materials off the surface enough to clear the Lagrange point. Earth gravity can then bring the materials to working orbit. A fleet of space tugs or ferries, operating perpetually up there, can help pilot the delivery pods to their precise orbit and location for actual manufacture. The entire affair can be made economically feasible by also mining the moon for profitable use back on Earth, such as precious metals, rare earths, and lithium.

Aside from having air to breath, the voyages of Columbus and the habitation of the Antarctic were not so far different. If the social and political will was there, it could be done.

Just an idea.

Re:Use the moon for materials. by iggymanz · 2018-02-19 13:13 · Score: 1

yes use the moon but why waste time printing? big things can be built with sheets and beams of metal smelted with solar energy.
Re:Use the moon for materials. by az-saguaro · 2018-02-19 13:42 · Score: 1

Good point, and true. But as others have also pointed out, some things are best manufactured on orbit, such as a mile long lightweight truss that would not do so well at the surface with gravity induced bending moments.

Re: Great! by SuricouRaven · 2018-02-19 10:55 · Score: 1

I've wondered about the possibility of launching giant expanding foam cans into LEO and squirting it out. The foam is low density, high cross-sectional area - perfect for objects to collide with, altering their velocity in a way that will probably result in burn-up. Then the foam, being highly susceptible to even the tiniest atmospheric drag, de-orbits in weeks to months. It'd be silly to try to sweep all of LEO that way, but still curious just how infeasible it is.

in space, isn't cooling a larger problem? by lpq · 2018-02-19 11:36 · Score: 1

Given the vacuum insulation around everything, isn't cooling a much larger problem in space than on earth? Given the problems of heat dissipation on earth, wouldn't they be worse in space?

Second issue is speed. Speed of light is an issue for signal propagation across circuits in today's computer design -- if the idea is to create larger machines in space, won't that get worse?

Re:Planetary Dyson Sphere by rednip · 2018-02-19 12:04 · Score: 1

Even if you solve the 'Mr Burns blots out the Sun' problem (make most of it out of glass maybe) you run into at least two biggest problems of a Dyson sphere

The amount of materials needed for such a structure would far exceed any readily available supply, possibly even within the entire solar system.
The changes in gravity would likely doom life on earth, at least as we know it.

--
The force that blew the Big Bang continues to accelerate.

Biggest machines in space by ScrewMaster · 2018-02-19 12:07 · Score: 1

But of course. Immensity can be bought very cheaply in space.

--
The higher the technology, the sharper that two-edged sword.

There are many silly ways to look at this nonsense by RhettLivingston · 2018-02-19 13:13 · Score: 1

If we stick to ships, the Prelude is six times larger than the Allure of the Seas in displacement at 600,000 tons and covers an area around 5 times that of the International Space Station at 450 tons.

This mismatch in weight vs size is the somewhat lame point the article's premise is based on.

I could change the equation dramatically by talking about the size of a blimp versus the ISS. The Hindenburg had a footprint larger than the ISS, weighed half as much, and enclosed more than 200 times the volume.

Also, certainly it is easy to argue that the ultimate size of machines in space is larger than is possible on Earth... or is it? What if we were to start completely covering Earth in shells of very strong engineered material, gradually transferring material from under the shells and building both downwards into the evacuated space and upwards as we do so, until we consume all of the Earth's material to the center of the Earth. We'd essentially be turning our planet into a vastly larger in volume, much lower density, satellite. We could throw in the moon's materials while we are at it. At that point, we suddenly see Earth as the very large machine in space it already is today.

Re: Great! by ShanghaiBill · 2018-02-19 13:46 · Score: 1

NASA has used aerogel to capture micrometeorites.

Your foam idea would require a spaceship to rendezvous with each object. Fuel consumption would be uneconomical. A ground based laser would be way cheaper.

Re:Great! by semper_statisticum · 2018-02-19 16:31 · Score: 1

Space is big, dude. Do you know how many paperclips you can make out there?

42?

--
The Spanish Inquisition of Psychometrics; Burning all the heretics.

Hideously expensive and hard by sjbe · 2018-02-20 00:23 · Score: 1

Space mining and ore processing has major advantageous over earth bound processing.

It POTENTIALLY has advantages. It also has a lot of disadvantages. We know some of each and there undoubtedly are a lot of advantages and disadvantages we have yet to learn about. Most of the conjecture I read here on slashdot is the sort of uninformed musings you get from a science fiction story rather than evidence based engineering. What is 100% clear however is the economics of doing this which are hideously expensive and will remain so for a long time to come. There are technical obstacles that probably can be overcome but the biggest obstacles to doing space based mining will be economic ones and those are very well understood. Seriously, if we decide space based manufacturing is worthwhile (and it might be) it's going to be hugely expensive to bootstrap that industry because we have to build entire supply chains with technology we haven't yet developed in the most hostile environment imaginable for purposes we have barely begun to imagine.

Put that way though it sounds like a fun challenge. :-)

The first is the ore's aren't all oxygenated from earth's atmosphere, this means iron can be found in its raw form rather than the iron oxide that exists on earth.

Which is nice but it saves you some steps but adds others. Maybe you skip some (not all) of the refining but you have problems of material handling, heat dispersion, and more that are FAR easier to deal with on Earth if for no other reason than we have a lot of experience doing it and a lot of tools and methods to work with that we've had centuries to develop.

Another major advantage is that you can melt that ore with essentially a big magnifying glass and you have much longer to shape it because you don't' have air messing everything up.

That's not necessarily an advantage depending on what you are trying to do. A great deal of how materials perform is dependent on how their molecular bonds arrange. A lot of properties of materials we depend on actually come about precisely because of how they interact with oxygen and other molecules in our atmosphere. How we manage the heat and remove heat from materials matters a lot in what we get as a final product. Having longer to shape a material is not universally a positive trait though there are many cases where that would be helpful.

The hard part is getting metal-rich asteroids into earth orbit, not the actual mining or processing.

Two thoughts on that. 1) Getting asteroids into earth orbit is a TERRIBLE idea if it is anywhere close to Earth. If we have the ability to move asteroids around like that we also have the ability to drop them on to earth on a target of our choosing. They are de-facto weapons of mass destruction and we do not need more of those. 2) Your presumption that getting to the asteroids being the hard part is belied by the fact that we've already done that. We also already know how to build equipment to move them at least in principle. What we haven't done is develop ANY commercially viable equipment to transform an asteroid into useful products. We barely have a few research projects that are no where close to being able to turn raw iron into functional products. Your attempt to hand wave that as the easy part clearly indicates you don't work in manufacturing (I do) because if you did you'd immediately realize it is FAR harder than you are supposing.

We're probably further along on this than people realize, I expect private space companies will make this happen long before a government could probably entirely for space tourism to begin with.

No we most assuredly are not very far along with space based manufacturing. Our manufacturing prowess in space amounts to a few very small scale research projects. We are so far from commercially viable space mining or space manufacturing

Re: Great! by SuricouRaven · 2018-02-20 07:41 · Score: 1

I wasn't thinking big objects. I was thinking the tens of thousands of tiny paint flecks and metal shavings.

Re:Planetary Dyson Sphere by david_thornley · 2018-02-20 10:54 · Score: 1

The laws of thermodynamics apply everywhere. There are indeed energy requirements for what is proposed, and I would recommend staying within a few AU of, say, a G-class star in order to gather the energy.

--
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes

Re:Planetary Dyson Sphere by dryeo · 2018-02-20 10:58 · Score: 1

Never heard of an eclipse?

--
https://en.wikipedia.org/wiki/Inverted_totalitarianism

Re:Planetary Dyson Sphere by dryeo · 2018-02-20 11:06 · Score: 1

Fun getting that right as large releases of sulphate aerosols have often resulted in a few years of famine due to the global cooling. One example I came across the other day, https://en.wikipedia.org/wiki/...

--
https://en.wikipedia.org/wiki/Inverted_totalitarianism

Re:Planetary Dyson Sphere by Hal_Porter · 2018-02-20 11:43 · Score: 1

If they come from a volcano you've got no control over them. If you're pumping the sulphates with technology you can just turn down the flow rate.

You'd have some sort of international body which decided on what the flow rate would be. Kind of the Fed sets interest rates, except it would global and deciding whether to pump more or less.

--
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;

Re:Planetary Dyson Sphere by dryeo · 2018-02-20 12:23 · Score: 1

Oh, it's possible and worth considering. The problem is that climate science deals a lot with chaotic systems. Sorta like hydrology (or whatever you call studying river flows or ocean currents). You can dump rubber ducks in a river and have a high confidence that most will end up downstream, but it is hard or maybe impossible to predict the route of an individual duck or whether it'll even arrive. Ocean currents are even harder, look at the friendly floatees, https://en.wikipedia.org/wiki/... climate science is similar, easy to say it is going to get warmer, hard to say exactly how warm and where and what affect more sulphates will have.
Have to consider unintended consequences as well, probably just an increase in acid rain but I'm reminded of the idiots that think that dumping iron in the ocean will help without considering that fertilizing the algae leads to excessive growth and oxygen usage, resulting in die outs due to lack of oxygen, massive amounts of rotting algae using up more oxygen and finally a dead zone in the ocean.
As I said, worth considering and perhaps using but ideally not depending on by itself. Probably the more diverse solutions, the better.

--
https://en.wikipedia.org/wiki/Inverted_totalitarianism

Re:Planetary Dyson Sphere by Hal_Porter · 2018-02-20 12:41 · Score: 1

Oh, it's possible and worth considering. The problem is that climate science deals a lot with chaotic systems.

Like the economy. In the UK there's a Monetary Policy Committee which sets interest rates based on looking at all the data.

https://en.wikipedia.org/wiki/...

If you had something analogous for climate control they'd look at all the data for he last year, try to work out what events might alter climate for the coming one (El Nino) and set the flow rate. If there was a volcanic eruption they could decide to change things at the next meeting.

In fact that's one advantage to controlling temperature via a sulphate pump over trying to regulate global CO2. Another is that you can't actually regulate global CO2 if China is responsible for most of the increases and they refuse to be regulated.

Have to consider unintended consequences as well, probably just an increase in acid rain

The Royal Society did a report on geoengineering where they concluded this was not an issue

https://royalsociety.org/topic...

https://royalsociety.org/~/med... page 45

The enhanced stratospheric sulphate layer which followed the eruption of Mt Pinatubo led to a signifi cant reduction in stratospheric ozone, with global ozone about 2% below the expected values (Harris et al. 1997). Tilmes et al. (2008) suggest that Arctic ozone depletion following geoengineering of the sulphate layer could be substantially increased and cause a delay in 'recovery' of the Antarctic ozone layer by perhaps up to 70 years (see also Submission: Tilmes). Also important could be more subtle changes in ozone in the middle latitude lower stratosphere; the connection between decadal scale climate variability and stratospheric ozone is increasingly being discussed (see for example, Baldwin et al. 2003; Shaw & Shepherd 2008). Indeed there is a range of so far unexplored feedback processes, which could become important with a permanently engineered sulphate layer. These could include increased stratospheretroposphere exchange (STE), driven by aerosol heating in the tropical lower stratosphere. This could have a long-term impact on stratospheric water vapour, and radiative forcing (see Joshi & Shine, 2003); increased STE would also lower the lifetime of the aerosol layer, calling for increased injections to maintain a particular value of the optical depth.

Changes in surface water and soil moisture as well as in solar radiation intensity at the surface would both be expected to have an impact on the biosphere and there are indications that the carbon cycle did change after the eruption of Mt Pinatubo since changes in the rates of increase of atmospheric CO2 and CH4 were observed (IPCC 2007a). No assessment of this in the geoengineering context has yet been carried out. An increase in acid rain appears to be unlikely to be a problem, as the perturbation to the global sulphur cycle by these stratospheric emissions is quite small (natural volcanic emissions are ~50 MtS/yr, and industrial emissions are much larger).

Delivering between 1 and 5 MtS/yr to the stratosphere is feasible. The mass involved is less than a tenth of the current annual payload of the global air transportation, and commercial transport aircraft already reach the lower stratosphere. Methods of delivering the required mass to the stratosphere depend on the required delivery altitude, assuming that the highest required altitude would be that needed to access the lower tropical stratosphere, about 20 km, then the most cost-effective delivery method would probably be a custom built fl eet of aircraft, although rockets, aircraft/rocket combinations, artillery and balloons have all been sugg

--
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;

Re:Planetary Dyson Sphere by dryeo · 2018-02-20 15:27 · Score: 1

Interesting, thanks. I am surprised they are talking about so little aerosols. And they would have to be maintained or increased as industry cleans up.

--
https://en.wikipedia.org/wiki/Inverted_totalitarianism

Re:Planetary Dyson Sphere by angel'o'sphere · 2018-02-21 11:58 · Score: 1

I suggest to google "law of thermodynamics" and read the relevant wikipedia articles before you make even more an idiot about your self.

Hint: thermo! What does thermo mean? hu?

--
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.

Slashdot Mirror

Humanity's Biggest Machines Will Be Built in Space (popularmechanics.com)

101 of 147 comments (clear)