"Mining the Sky" for Earth?

[Ben Banana]

"Mining the Sky" for Earth? Why is there only talk of bringing it back down to Earth? What would we even do with such resources? Most Sci-Fi resides beyond Earth.

 

 

Megastructures are under my eye (i.e. spaceships, Dyson spheres and artificial worlds!) Zero-gravity provides a very free medium which should simplify automated construction. Automatized production systems could be highly modular, reproductive and self-maintaining; principles which yield a system capable of building virtually anything we can imagine that is theoretically-feasible! I think we should do our best to live within the confines of Earth and crunch down as much efficiency as we can before considering extraterrestrial resources as core supplements, so I believe that we should extend beyond Earth with distributed (even discrete) ventures, rather than with the ambition to supply an extremely centralized system. I guess the term 'Astrology' would be renewed for an engineering practice, and that's just fruit-loopin cool.

 

And, your thoughts?

[Phi for All]

I don't share your concern. There are plenty of projected plans for asteroid mining that would bring the resources to offworld destinations.

 

From the Planetary Resources website:

Asteroid mining will allow the delivery of resources to the point of need, be it a fuel depot orbiting the Earth, or elsewhere in the Solar System.

 

AFAICT, bringing almost anything back to Earth would make it so expensive it would be worthless, even if it was a truck-sized chunk of platinum.

[Moontanman]

I don't share your concern. There are plenty of projected plans for asteroid mining that would bring the resources to offworld destinations.

 

From the Planetary Resources website:

 

 

AFAICT, bringing almost anything back to Earth would make it so expensive it would be worthless, even if it was a truck-sized chunk of platinum.

 

 

I disagree, heat shields could be made and lots of really large chunks would only have to be slowed to the point that the contents would not be spread over the earth. it wouldn't be as difficult as bringing back a man alive... as long as it remained relatively intact a chuck of platinum it would be valuable.

[Phi for All]

I disagree, heat shields could be made and lots of really large chunks would only have to be slowed to the point that the contents would not be spread over the earth. it wouldn't be as difficult as bringing back a man alive... as long as it remained relatively intact a chuck of platinum it would be valuable.

I don't think the danger involved in bringing them out of orbit is worth any kind of prolonged project. The more you do it the more chances for disaster, especially when there will be plenty of need for precious metals in offworld applications.

[md65536]

I disagree, heat shields could be made and lots of really large chunks would only have to be slowed to the point that the contents would not be spread over the earth. it wouldn't be as difficult as bringing back a man alive... as long as it remained relatively intact a chuck of platinum it would be valuable.

It's not just the cost of bringing it down that's the problem, but of getting to it and mining it in the first place. It's not worth it to get something from space, when the same thing can be obtained here on Earth for much cheaper. There's no resource needed, at least not yet, that would make this cost effective.

 

However, if you need the material to be in space anyway, then the cost of mining it on Earth and also then sending it up into space can become great enough to outweigh the extra cost of mining it in space.

 

 

It's not just the value of the materials that we're talking about, nor just the differing costs of mining it from different places, nor just the cost of transporting it to where it's needed, but a combination of factors that will be different for different situations or locations.

Edited September 22, 2012 by md65536

[Phi for All]

It's not just the cost of bringing it down that's the problem, but of getting to it and mining it in the first place. It's not worth it to get something from space, when the same thing can be obtained here on Earth for much cheaper. There's no resource needed, at least not yet, that would make this cost effective.

 

However, if you need the material to be in space anyway, then the cost of mining it on Earth and also then sending it up into space can become great enough to outweigh the extra cost of mining it in space.

 

 

It's not just the value of the materials that we're talking about, nor just the differing costs of mining it from different places, nor just the cost of transporting it to where it's needed, but a combination of factors that will be different for different situations or locations.

I agree. If platinum mined on Earth sells for $1500 an ounce, any platinum mined from an asteroid and brought back down to Earth is going to cost a great deal more. Unless it somehow has extra properties that Earth platinum doesn't have, why pay extra for it? And if you're not going to charge more for it, why bother to go offworld for it?

 

The only profitable scenario I see for bringing it back to Earth will be a short-term one. I can see people paying more for jewelry or art made from "alien metals", but only until increased supply diluted the exotic nature of the purchase.

[dmaiski]

humm the quick and dirty method for mining an asteroid

1. take an asteroid in the belt

2. strap a thruster to it to lob it on a collision course with earth

3. automated mining systems shed the majority of the useless mass on the asteroid into space (useless junk like ice, common elements, stuff we don't use)

4. section the usable mass into a series of small meteorites

5. small correctional thrusters align the asteroids into optimal position for a controlled decent into your "landing field"(an unpopulated area, like the place they used to test nukes)

6. use the excess shed mass that was useless to form the "heat shield"

7. bombs away (you lob the meteorites into the atmosphere and let them hit the "landing zone"

8. retrieve your minerals

 

total cost:

relatively small amount of flue(you could use solar panels and heat ice to provide thrust)

reusable mining robots

a large plot of land for your "landing zone"

bribes, tributes, or "tax" to government/space regulatory body for their great service of "oversight" of the project

 

*really the most quick and dirty method to mine metal for terrestrial use in space

**the ice heat shield is burnt away during re-entry

***this assumes you have a few monts-years to mine the asteroid while it is in transit to earth

****most of the cost for any space mining will be in paying off the tax man, some government regulatory body, or hiring assassins to kill said government body

*****if there is not enough ice on the asteroid you mine, you can always get another one for the ride that is made of ice

******this method dose require some reshuffling of the positions of the orbital hardware that's in the way

*******we do have the maths to calculate orbital trajectory, re-entry angles, and all that stuff

******** the most advanced piece of thechnology used here is the mining robots, evrything else is backyard science

********* "oversight" implies that the government will want a cut of what you are mining just because they have the guns to support the demands, and no actual oversight will be done(except for token efforts by under trained, understaffed, inspectors for extortionate cuts of the net)

Edited September 25, 2012 by dmaiski

[Ophiolite]

You've overlooked the cost of the damages when your navigation system fails very badly indeed.

[dmaiski]

You've overlooked the cost of the damages when your navigation system fails very badly indeed.

 

that's why you put the heat shields on last

it nav fails all that happens is you lose a tone of metals due to burn up in atmosphere

if nave fails early on, its easy to fix changing trajectory in space is the most simple thing in the universe

 

the worst thing is it will look and sound like an extraterrestrial bombing run when the rocks come down, that's why you need cheap land to crash your rocks into

 

*this assumes the space faring industry is sufficiently developed to manage such a system

 

 

Edited September 25, 2012 by dmaiski

[CaptainPanic]

that's why you put the heat shields on last

it nav fails all that happens is you lose a tone of metals due to burn up in atmosphere

What Ophiolite probably means is that if you miss the target area, and hit a city instead, the costs are huge.

 

I agree with md65536 that asteroid mining only makes sense if you need your materials in space anyway.

[Ben Banana]

You've discussed celestial resource-gathering (asteroid mining) quite a bit. I don't have any more comments regarding this particular aspect of the topic's discussion yet.

 

I have an idea for processing materials and resources within the *vacuum of space and zero-gravity. What do you think about utilizing artificial fusion as a core heat source (e.g. to melt things during metallurgic refinement)? I think we could discover a much broader variety of applications for fusion when considering its practice within space, which I suppose would happen to be a lot cheaper to construct than projects such as the ITER tokamak (which is probably fundamentally different in operational nature to my idea), due to the simplicity I assume is associated to performing controlled fusion in space. Of course, this is just a fat assumption I make, as I find it reasonable to believe fusion and space naturally go hand in hand. After all, what do stars do? Yet, when I speculate this practice a little more deeply (though still too vague and inexperienced of me to discuss), I do think the idea could work quite well.

 

If this is completed into a closed system -- gathering, refining, constructing; constructing new equipment for gathering raw-resources, expanding the facility of refinement, and assembling more construction utility -- I think it's just a matter of fully deploying the first generation of equipment, and then we shouldn't need to do very much to sustain its growth (besides overhead instruction). Of course, depending on how much equipment you initially deploy, time will always be a great matter, though I still believe the system could thoroughly develop to yield production masses far greater than as produced by all the humans working on Earth (collective measurement) in a rather short time, comparatively.

 

As of now, this is not really a legitimate engineering topic, but I'm just opening my ideas for discussion. We can discuss the best plausible techniques for practicing metallurgic refinement within space, and even some concepts relating to their concrete practice (specific matters of engineering). I admit that I naively suspect the potential for such practices to bear more successfully than any mass metallurgic-process currently operating on Earth, but I want to know if you foresee any complications as early as now (and even if you don't, that doesn't mean I have any exceptionally good ideas here).

 

The next subject we haven't touched upon is the necessary array of modular construction utility which would be required to completely close this system. I'd broadly divide this array into the following categorization (anyone think they're a good manufacture-taxonomist?):

 

• Domains of Construction
  
  • Basis of Manufacture
    
    • Casting
      
    • Machining
      
    • Specialist/Miscellaneous Processes (e.g. pressing, grinding, inflating etc.)
      

    [*]The equivalent to cranes, train tracks and all forms of macro assembly.

    [*]...

  [*]Targets of Construction

  • Facilitative Frameworks (if it really is best for the total system to actually be this discrete and compartmental i.e. mining hubs, metallurgic centers, construction cores etc.)
    
  • Giant teddy bears.
    
  • ...
    

  [*]The Framework of Construction-Facility

  • Routing
    
    • Delivery of Resources and Materials
    • Ensemble-management of Constructive Components
    • Route Behavior (Compression, relaxation; various issues of complexity)

    [*]Hierarchy

    • Apples and oranges.
      
    • Guns and bunnies.
      
    • Orange bunnies who taste like apples with guns.
      
    • Hairspray.
      

    [*]...

  [*]Some other stuff (well, lots of stuff) which isn't included because this vague and extremely incomplete taxonomy is merely illustratively directed towards the course of discussion.

Edited September 28, 2012 by Ben Bowen

[Robert Clark]

I agree. If platinum mined on Earth sells for $1500 an ounce, any platinum mined from an asteroid and brought back down to Earth is going to cost a great deal more. Unless it somehow has extra properties that Earth platinum doesn't have, why pay extra for it? And if you're not going to charge more for it, why bother to go offworld for it?

The only profitable scenario I see for bringing it back to Earth will be a short-term one. I can see people paying more for jewelry or art made from "alien metals", but only until increased supply diluted the exotic nature of the purchase.

At $1,500 per once, that's $24,000 per pound, $52,800 per kilo. Launch costs to LEO are about $10,000 per kilo now. Robert Heinlein famously said once you reach Earth orbit, you're half way to anywhere in the Solar System. So we can estimate getting to an asteroid as twice that cost. If you take the cost to get back as about the same then this total is still less than $52,800 per kilo.

Also, SpaceX expects to offer launch to orbit at $2,000 per kilo on the Falcon Heavy, which improves the economics even further.

 

Another company has announced asteroid mining intentions:

 

Asteroid-Mining Project Aims for Deep-Space Colonies.

by Mike Wall, SPACE.com Senior Writer Date: 22 January 2013 Time: 12:01 AM ET

http://www.space.com/19368-asteroid-mining-deep-space-industries.html

 

This is good news. My opinion is that space mining will prove to be the "killer app" that will make space flight routine. More companies entering the field will increase competition, and increase innovation. This will serve to advance the speed at which such a venture can come to fruition.

 

Deep Space Industries. (sales video)

 

 

Deep Space Industries Live Announcement.

 

 

I like the optimistic approach taken in these videos. It's the idea espoused by Peter Diamandis that the upcoming times will be a period of abundance, not of need.

 

Bob Clark

 

Edit: The system won't allow youtube links. You can find the videos on youtube at the above titles.

Edited February 11, 2013 by Robert Clark

[Phi for All]

At $1,500 per once, that's $24,000 per pound, $52,800 per kilo. Launch costs to LEO are about $10,000 per kilo now. Robert Heinlein famously said once you reach Earth orbit, you're half way to anywhere in the Solar System. So we can estimate getting to an asteroid as twice that cost. If you take the cost to get back as about the same then this total is still less than $52,800 per kilo.

 

Do your launch and re-entry costs include the actual costs of mining the asteroid to collect the platinum? Even without those costs, my earthly competition is making a great deal more profit, so why am I risking so much to bring it back to Earth?

 

Check out this blog post. I'm not sure I completely agree with some of this guy's assumptions, but I think he's taking more into consideration than either of us is.

 

I still say the best use of metals we find in space is build more ways to explore space, rather than try to bring it back down. We'll need it out there, so why not use it out there?

[Moontanman]

Do your launch and re-entry costs include the actual costs of mining the asteroid to collect the platinum? Even without those costs, my earthly competition is making a great deal more profit, so why am I risking so much to bring it back to Earth?

 

Check out this blog post. I'm not sure I completely agree with some of this guy's assumptions, but I think he's taking more into consideration than either of us is.

 

I still say the best use of metals we find in space is build more ways to explore space, rather than try to bring it back down. We'll need it out there, so why not use it out there?

 

 

My main question for that blogger would be why is there a limit to how much X amount of mining equipment can mine? Then there is the concept of Von Neumann machines While I do think such mining is going to be hard, at least at first and I do think the most likely use for such mining will be to use the materials in space I don't think the costs can be so easily used to dismiss the idea...

[Phi for All]

My main question for that blogger would be why is there a limit to how much X amount of mining equipment can mine?

 

Unless you're repairing your equipment offworld, or have the self-replicating machines you mentioned, it's too expensive to bring it back down, repair it and send it back out. I wonder if even self-replicating machines could reproduce hardened drill bits cost-effectively on their own. It would seem like at least part of the machines would be better off being manufactured in an offworld facility.

[Moontanman]

Unless you're repairing your equipment offworld, or have the self-replicating machines you mentioned, it's too expensive to bring it back down, repair it and send it back out. I wonder if even self-replicating machines could reproduce hardened drill bits cost-effectively on their own. It would seem like at least part of the machines would be better off being manufactured in an offworld facility.

 

 

I think this comes close to being an axiom for space mining... anything that can be made in space should be made in space... and repaired in space..

[Enthalpy]

 

 

...heat shields could be made... as long as it remained relatively intact, a chuck of platinum would be valuable.

It doesn't need a heatshield. Splash 1kg or 1t of platinum in the Ocean or the Antarctica or the Sahara. The atmosphere won't do any harm to a piece of solid metal. Finding the collision debris is less easy.

 

The real limit is: putting anything on an asteroid, and much worse bringing it back, costs more than platinum's value. I consider the varied attempts as obviously hopeless from the beginning. But never mind, those who funded them can live with a few millions less.

[Moontanman]

It doesn't need a heatshield. Splash 1kg or 1t of platinum in the Ocean or the Antarctica or the Sahara. The atmosphere won't do any harm to a piece of solid metal. Finding the collision debris is less easy.

 

The real limit is: putting anything on an asteroid, and much worse bringing it back, costs more than platinum's value. I consider the varied attempts as obviously hopeless from the beginning. But never mind, those who funded them can live with a few millions less.

 

 

I'm curious, did you read post #12?

[Robert Clark]

A science-fiction film from 1969 also expressed the idea that

asteroid mining could only be profitable by bringing the asteroid to

the vicinity of the Earth, so I suppose this is a view that has long

been expressed. The film was "Moon Zero Two":

 

Moon Zero Two - Wikipedia, the free encyclopedia

 

The film was a rather low budget endeavor, still it was enjoyable for

a genre fan. It can be purchased on Amazon.com. However, you can see

it for free on Youtube if you don't mind the Mystery Science Theater

3000 side comments:

 

MST3k 111 - Moon Zero Two.

 

 

BTW, the two "Deep Space Industries" videos I mentioned are at:

 

Deep Space Industries. (sales video)

 

Deep Space Industries Live Announcement.

 

 

Bob Clark

 

 

 

My main question for that blogger would be why is there a limit to how much X amount of mining equipment can mine? Then there is the concept of Von Neumann machines While I do think such mining is going to be hard, at least at first and I do think the most likely use for such mining will be to use the materials in space I don't think the costs can be so easily used to dismiss the idea...

Yes, I noticed that too. Front-end loaders, dump trucks, etc. can last for decades with maintenance. This means many thousands or hundreds of thousands times greater mass can be mined than their mass.

 

Bob Clark

Edited February 11, 2013 by Robert Clark

[D H]

Check out this blog post. I'm not sure I completely agree with some of this guy's assumptions, but I think he's taking more into consideration than either of us is.

 

I don't agree with his assumptions, either.

 

He is wildly overoptimistic, is rather ignorant both economically and technologically.

 

 

His baseline platinum concentration of 0.3% is highly unrealistic. The best targets for platinum are the LL chondrites and the iron-nickel asteroids. A concentration of 0.006% is optimistically realistic. That's the 98^th percentile concentration in iron nickel asteroids. A concentration of 0.3%? That's straight out of science fiction woo-woo land. His alternate 4.1% figure is beyond science fiction.

 

A mere 2500 kg mining machine -- that's roughly what we have on Mars right now. The Mars Curiosity rover recently drilled a 2.5 inch deep, 0.63 inch diameter hole into a nice soft sedimentary rock. It took a while. That factor of 100 is pretty much useless if this 2500 kg machine of his eventually does mine 100 times its weight but takes five billion years to accomplish this task. Time is of the essence.

 

My full-size pickup weighs more than his 2500 kg mining machine, and no matter how well equipped, it would take a long, long time for it to rip through 2,500,000 kg of rock. My pickup is powered with gasoline, a much more concentrated energy source than solar power. When it runs out, I drive to the nearest gas station. There are no nearby gas stations on an asteroid. Where is this 2500 kg mining machine going to get the energy needed to rip through 2,500,000 kg of rock?

 

Where is this 2500 kg machine going to get the drill bits that have been worn smooth? Where is it going to get dynamite so it doesn't have drill through every bit of the asteroid? How are they going to pack drilling equipment, hauling equipment, refining equipment, and lots and lots of spares into 2500 kg?

 

How are they going to get the mined material back to Earth? There's no budget for and no mention of that expense, and it's not little.

[Moontanman]

D H = spoilsport... reality is seldom what we want it to be... hard facts are so painful to swallow...

[D H]

At $1,500 per once, that's $24,000 per pound, $52,800 per kilo. Launch costs to LEO are about $10,000 per kilo now. Robert Heinlein famously said once you reach Earth orbit, you're half way to anywhere in the Solar System. So we can estimate getting to an asteroid as twice that cost.

No, you can't. You're halfway there in terms of delta V. The problem is that cost is not a linear function of delta V. It's exponential at best. Oftentimes it's worse than exponential. The ideal rocket equation is brutally exponential, and reality, which is worse than idea, is even more brutal.

[Robert Clark]

No, you can't. You're halfway there in terms of delta V. The problem is that cost is not a linear function of delta V. It's exponential at best. Oftentimes it's worse than exponential. The ideal rocket equation is brutally exponential, and reality, which is worse than idea, is even more brutal.

Actually the cost estimate is taking into account the rocket equation. What Heinlein's statement was based on was that after you get to LEO to get to escape velocity you need an additional 3.1 km/s delta-V. By the rocket equation, using efficient hydrogen-fueled engines this about doubles the size of your rocket for the same size payload. So Heinlein was not saying the delta-V doubled, he was saying your rocket size doubled, which approximately doubles your cost.

 

 

 

 

I don't agree with his assumptions, either.

He is wildly overoptimistic, is rather ignorant both economically and technologically.

 

His baseline platinum concentration of 0.3% is highly unrealistic. The best targets for platinum are the LL chondrites and the iron-nickel asteroids. A concentration of 0.006% is optimistically realistic. That's the 98^th percentile concentration in iron nickel asteroids. A concentration of 0.3%? That's straight out of science fiction woo-woo land. His alternate 4.1% figure is beyond science fiction.

A mere 2500 kg mining machine -- that's roughly what we have on Mars right now. The Mars Curiosity rover recently drilled a 2.5 inch deep, 0.63 inch diameter hole into a nice soft sedimentary rock. It took a while. That factor of 100 is pretty much useless if this 2500 kg machine of his eventually does mine 100 times its weight but takes five billion years to accomplish this task.

We agree his numbers aren't accurate in either direction. GIGO, as they say in computer science.

 

A more relevant mining comparison to mining the asteroids would be like the large bucket excavators used in strip mining, since the valuable minerals are distributed uniformly throughout the asteroid. For the Mars rovers you were doing fine instrument measurements, not excavating large mass.

 

 

Bob Clark

Edited February 12, 2013 by Robert Clark

[D H]

Actually the cost estimate is taking into account the rocket equation. What Heinlein's statement was based on was that after you get to LEO to get to escape velocity you need an additional 3.1 km/s delta-V. By the rocket equation, using efficient hydrogen-fueled engines this about doubles the size of your rocket for the same size payload. So Heinlein was not saying the delta-V doubled, he was saying your rocket size doubled, which approximately doubles your cost.

 

Nonsense.

 

The rocket equation is a nasty, brutal thing. Here's one version: [imath]\Delta v = v_e \ln(m_0/m_1)[/imath], where [imath]\Delta v[/imath] is the change in velocity, [imath]v_e[/imath] is the effective exhaust velocity, [imath]m_0[/imath] is the initial mass of the vehicle, including fuel, and [imath]m_1[/imath] is the final mass (all fuel consumed) of the vehicle. Here's another: [imath]m_f = (m_s+m_p)(\exp(\Delta v/v_e)-1)[/imath], where [imath]m_f[/imath] is the mass of the fuel needed to achieve the desired [imath]\Delta v[/imath] given a payload mass of [imath]m_p[/imath] and a vehicular structural mass of [imath]m_s[/imath].

 

Notice the natural logarithm in the first form, the exponential in the second. Either way, the rocket equation is exponential. Costs are anything but linear with respect to [imath]\Delta v[/imath].

 

In fact, the rocket equation is worse than exponential. Naively applying the rocket equation quickly leads to a vehicle that is initially 99% or more fuel. We don't know how to build such a vehicle. At some point you need a bigger rocket. That means even more fuel, even more vehicular structure, even more costs.

 

There's yet another problem that gets in the way, which is the cube square law. Making a rocket whose initial mass is 99% fuel is not a big problem if the rocket is rather small. Make the rocket as a whole bigger and the cube square law demands that that initial fuel load decrease as a percentage as vehicle mass increases. For an extremely large rocket the upper limit on the initial fuel load is closer to 90% than 99%.

 

Using a multistage rocket is one way to somewhat contravene the nastiness of the rocket equation. It's still exponential, however, and adding stages increases costs by a non-linear factor. A multistage solution also increases structural integrity issues. The initial stages have to have enough structural integrity to bear their own weight under thrust plus all of the loaded weight of the stages above.

 

A prime example: The Apollo moon missions. The Gemini missions which preceded the Apollo missions were about halfway to the surface of the moon (and back) in terms of delta V. Doubling the delta V did a whole lot more than double the cost. Had we stopped with Gemini the costs of the 1960s human space program would have been an order or magnitude smaller than they were, or even less.

 

 

We agree his numbers aren't accurate in either direction.

 

No, we should agree that his numbers are ridiculously optimistic, economically and technologically naive, and omit a significant number of costs.

 

Precious metals will be amongst the last things mined in space, not the first. The first will be water and volatiles such as methane. Then (maybe) we'll go after common metals such as iron and nickel. Regarding that parenthetical "maybe": We won't do any of this if we focus only on the immediate return on investment. Space mining will be a loss leader rather than a profit center for a long, long time.

 

Only with a vibrant space mining economy will we have the massive infrastructure in place to go after the very small quantities of precious metals and rare earths that are present in mineable quantities in a small percentage of the asteroids. Even then, our space-faring successors will have to be careful not to flood the market and turn those precious metals and rare earths into semi-precious metals and not-so-rare earths.

 

 

A more relevant mining comparison to mining the asteroids would be like the large bucket excavators used in strip mining, since the valuable minerals are distributed uniformly throughout the asteroid.

 

Those large bucket excavators are just a tad more massive than 2500 kg. There any many different kinds of machines involved, many of which are gargantuan compared to that mythical 2500 kg mining machine. Those large bucket operations eat through parts at a phenomenal rate, consume immense amounts of energy, and rely heavily on dynamite.

 

The uniform distribution is not a feature. It's a misfeature. Those large bucket operations are only economical where the target metals are concentrated by some fluke of nature.

[Enthalpy]

I'm curious, did you read post #12?

SpaceX sells its Falcon 9 for some 80M$ presently. Two more boosters won't make it cheaper, so 32,000kg in Leo would cost >>2500$/kg.

 

Then going from Leo to an asteroid and braking there means >3+3km/s. Even with hydrogen, the instruments put there must be >4 times lighter.

 

After what you must consider the mass of the machines needed to extract a single kg of precious metal. The excavator isn't all: metals must be reduced and separated.

 

Even the way back costs some mass, because the transport vessel needs some communications, trajectory control... Which won't be much lighter than the smallest probes sent to other worlds, like 200kg, whose 600kg including fuel must first be landed smoothly on the asteroid.

 

-----

 

You can compare with materials made in Leo, which is easier to attain and come back from. People wanted to grow protein crystals and semiconductor crystals, both being more expensive than platinum, and needing no multiton machines for one kilogram. Economic fiasco.

 

-----

 

Besides the many technical issues which let the attempts look to my eyes like a target for a governmental research project rather than an industrial development, I fear the initiative comes from people who don't know how to begin with the task. For sure, I've read strictly none of the many and very exotic breakthrough demanded by the enterprise.

 

The general scheme must be: find an exotic idea that bears huge promises, sell it to a billionaire, then ask on Internet forums how to give the customer a few scientific-looking arguments. And... Did I meet these guys on an other forum?

 

Reminds me of the ones who sold breeder reactors to Bill Gates. Everyone knows what breeders would solve, that no really good design exists, and that breeders have inherent huge drawbacks - but they came with a much more difficult design, which was certainly impossible, full of gross mistakes, and they managed to sell it. Meanwhile they seem to have hired a few pople who understand something about reactors, but well, that can't possibly suffice.