[HN Gopher] Against all odds, an asteroid mining company appears...
       ___________________________________________________________________
        
       Against all odds, an asteroid mining company appears to be making
       headway
        
       Author : bookofjoe
       Score  : 102 points
       Date   : 2024-08-24 13:05 UTC (9 hours ago)
        
 (HTM) web link (arstechnica.com)
 (TXT) w3m dump (arstechnica.com)
        
       | PaulHoule wrote:
       | Platinum-group metals on earth: $965/oz
       | 
       | Water, volatiles and carbonaceous materials anywhere else in the
       | solar system: priceless
        
         | credit_guy wrote:
         | Not really. You can't set up a "gas station" somewhere in the
         | Solar system. It has to orbit. Anything in orbit goes many,
         | many times faster than a bullet. Aligning yourself with such a
         | fast moving object is doable, but costs a lot of fuel. Then
         | detaching yourself from that orbit in order to go to your
         | original destination burns a lot of fuel too. But let's say you
         | get more fuel from that station than you burn. Who is going to
         | replenish the station, and how? They need to burn a lot of fuel
         | too, to go to an asteroid and back. It's not completely
         | impossible, but it's quite unlikely.
        
           | PaulHoule wrote:
           | Where did I say I'd waste volatiles moving things around?
           | 
           | (1) Build a solar sail factory on a CC asteroid and you can
           | deliver sunshades to Earth-Sun L1 without wasting volatiles
           | as reaction mass
           | 
           | (2) If you read this paper and really thought about it
           | 
           | https://arxiv.org/pdf/2011.07487
           | 
           | You'd realize that it strictly dominates all other space
           | colonization schemes that have been proposed because it
           | doesn't waste volatiles for transportation. Certainly
           | O'Neill's ideas look infeasible in comparison (where do you
           | get the nitrogen to fill those big airspaces? My plan for a
           | baby Bernal sphere intended to be a luxury hotel in LEO still
           | takes 15 starship loads of LN2 for the atmosphere)
           | 
           | Even Musk's plan to colonize Mars is something that only
           | makes sense to people who were born on a planet. If "grabby"
           | aliens capable of interstellar travel and building such
           | things here they might find the Earth a curiosity at best.
        
             | mapt wrote:
             | Solar sails are at this time quite useless for most
             | purposes, and always will be if we can't build, fold, and
             | deploy working sails of micrometer thickness, and/or build
             | gigawatt-scale laser launch projectors.
             | 
             | Using ion thrusters it is already the case that we have
             | access to power-generation-limited domain of specific
             | impulse; Nobody thinks a mission at 30,000isp instead of
             | 3,000isp is superior for interplanetary because of the
             | sheer amount of waiting time and the extreme mass fraction
             | of the solar panels. Solar sails, even moreso.
             | 
             | And one more dream to kill - large open volumes are
             | probably never going to happen. This is implied by the
             | mathematical engineering reality of the thin-walled
             | pressure vessel, whose minimum mass scales directly with
             | (volume * pressure) / tensile strength. Contrary to my
             | naive expectations, there is no square cube ratio to the
             | structure of a pressure vessel, so every cubic meter costs
             | mass.
        
               | firesteelrain wrote:
               | Solar sails and large open spaces face big challenges,
               | but experiments like JAXA's IKAROS, the LightSail
               | missions, and NASA's NanoSail-D2 have shown that solar
               | sails can work in space.
        
               | TheCraiggers wrote:
               | Isn't that a bit like saying the solar car cross-country
               | races show that solar-powered cars can work? In both
               | cases the 'payload' and vehicles are stripped to the
               | barest essentials.
               | 
               | Solar sails with any significant mass attached to them
               | would either need to be impossibly large, and/or operate
               | on timescales that make ion propulsion seem like a warp
               | drive. And that's not counting the issue of _stopping_
               | when you get to your destination, which will either
               | require some insane laser /power source already at your
               | destination, or propellant- in which case you're back to
               | just using that in the first place.
        
               | firesteelrain wrote:
               | You're right. Solar sails need to be massive to move
               | anything heavy, and they take a long time to build up
               | speed. Stopping is another big hurdle. But they're not
               | supposed to replace everything. They're useful when you
               | can't carry fuel, like on really long missions. They're
               | slow, but they work for what they're designed to do: keep
               | going without needing fuel.
        
               | PaulHoule wrote:
               | Funny, a low performance solar sail is actually a high
               | performance sunshade, you'd actually do better with a
               | black sunshade than a highly reflective one.
        
               | PaulHoule wrote:
               | Somebody pointed out to me that IKAROS didn't last that
               | long (neither did its namesake), so far that's the best
               | rebuttal to my L1 sunshade plan but I'd imagine a second
               | generation product could do better. People so forget that
               | space is a corrosive environment that will wreck many
               | materials.
               | 
               | https://en.wikipedia.org/wiki/Long_Duration_Exposure_Faci
               | lit...
        
       | dylan604 wrote:
       | "The docking mechanism is simple--since the asteroid is likely to
       | be iron-rich, Vestri will use magnets to attach itself."
       | 
       | While that sounds simple, it does make it sound like the mining
       | part just became much more difficult.
       | 
       | Thinking about some of the sci-fi regarding asteroid mining, I've
       | always liked the idea of bringing the asteroid to park into an
       | orbit around earth to make it easier/cheaper for multiple
       | deliveries, but I've always wonder what kind of ownership claims
       | that would imply. If I took the time and effort to park an
       | asteroid in orbit, would I have sole ownership of it or would you
       | be able to mine from it as well?
        
         | choeger wrote:
         | I don't think that moving the whole thing into our orbit would
         | make much sense.
         | 
         | The biggest amount of delta-v is necessary to leave Earth's
         | gravity well. Once you're there, going from and to asteroid is
         | time-consuming but doesn't need that much delta-v, moving ore
         | from the asteroid to Earth would cost some fuel, proportional
         | to the mass.
         | 
         | So moving it into orbit would save time but require us to pay
         | for the fuel all at once.
         | 
         | So why should someone do this, unless you need a permanent
         | human presence on the asteroid?
        
           | nordsieck wrote:
           | > So why should someone do this, unless you need a permanent
           | human presence on the asteroid?
           | 
           | Activity is only economically valuable if it is valued - i.e.
           | by people.
           | 
           | Unless there's a population of people living in space, the
           | ore or products derived from ore need to eventually make
           | their way to Earth in order to be worth while.
        
           | dylan604 wrote:
           | I think we're all scared of the actual question posed or
           | something as we've totally ignored it in everyone of these
           | responses.
           | 
           | Nobody cares in sci-fi about whether something should/could
           | be done. That's not the purview of the plot. It's also not
           | the purview of the original comment.
        
         | nordsieck wrote:
         | > I've always liked the idea of bringing the asteroid to park
         | into an orbit around earth to make it easier/cheaper for
         | multiple deliveries
         | 
         | I think you're dramatically underestimating the difficulty of
         | doing this.
         | 
         | If you look at rockets, they're 90-95% propellant. Even
         | relatively svelt upper stages like Centaur III (the upper stage
         | from Atlas v) are more than 50% propellant. And that's for just
         | taking payloads to LEO - for higher energy missions, the usable
         | payload gets smaller, which means the percent of the upper
         | stage that's propellant increases.
         | 
         | How difficult would it be to get an amount of propellant, say,
         | 5 times the mass of the asteroid to the asteroid? You'd also
         | have to get the engines and other structures to let you use the
         | propellant in a productive way.
         | 
         | It's way easier to extract valuable parts from an astroid and
         | move a lot less mass there and back.
        
           | api wrote:
           | Moving mass back with a free return trajectory is much easier
           | than getting stuff out of Earths gravity well and up there.
           | Escape velocity from an asteroid is low and if you yeet it
           | with enough precision you can send it on a trajectory that
           | will land it on Earth.
           | 
           | As for moving the asteroid you could use extremely high
           | specific impulse ion thrusters, in situ propellant from the
           | asteroid itself, or a solar sail. But you are right that
           | simply firing the valuable stuff back to Earth is probably
           | easier.
        
           | lolinder wrote:
           | Not to mention the governance and liability implications of
           | the plan. If a company mining something on Earth screws up
           | _really_ badly, they can ruin the environment for a hundred
           | miles around. If a company mining an asteroid in LEO screws
           | up _really_ badly, the literal blast radius would wipe out a
           | significant percentage of life on earth.
        
             | dylan604 wrote:
             | Why does it need to be parked in LEO? It could be kept in
             | an orbit at the same distance as the Moon and it would
             | still be relatively close compared to where it is now
        
               | lolinder wrote:
               | Fair. I don't think we'd want that either, though, for
               | the same reason. The moon is too close for comfort for
               | smaller objects that we've proven we can move.
        
           | Teever wrote:
           | What about using the asteroid itself as fuel? Even if the
           | asteroid is devoid of hydrocarbons that could be turned into
           | fuel for conventional engines iron make a suitable (albeit
           | inefficient) fuel for ion thrusters powered by solar panels.
           | 
           | Mass drivers and linear rails are also viable ways of
           | bringing raw material into Earth's orbit from asteroids of a
           | certain size.
        
             | IgorPartola wrote:
             | This was my thought as well. Also for what it's worth iron
             | oxidation is slow but very exothermic.
             | 
             | So what you'd want is a LEO starting point/station. You
             | launch a barge from there to snag an asteroid. You could
             | use a mass driver using solar or nuclear and mass from a
             | previously spent asteroid to get to the asteroid belt, then
             | snag an asteroid and use its mass to get back. You strip
             | the important parts of it, construct a capsule for what you
             | mined, and nudge it so it falls someplace in say a shallow
             | part of the ocean. Then recover from there.
             | 
             | Or hell why mine it up there? Simply nudge an asteroid on a
             | collision course towards Earth to make sure it falls
             | someplace "safe". Sure most of it will burn up but not all.
             | It's free material after all.
        
               | dylan604 wrote:
               | Didn't the asteroid that destroyed the dinosaurs hit the
               | ocean?
        
               | IgorPartola wrote:
               | Sure. So size matters. If you drop a rock in the ocean it
               | doesn't darken the skies, does it?
               | 
               | Meteors fall onto Earth all the time. It is a matter of
               | composition, trajectory, and mass, no?
        
           | BobaFloutist wrote:
           | Ok, just park an ion drive on the asteroid and your
           | descendant's descendants' descendants' get to mine it from
           | LEO?
        
       | cletus wrote:
       | I'm not sure what substance you could mine on an asteroid that
       | could possibly be economical.
       | 
       | The first obvious assumption is would have to be launched from
       | space and return to space because the cost of getting a payload
       | from Earth to LEO is a huge extra expense.
       | 
       | Then you have to consider the delta-V of getting to the asteroid,
       | doing a rendezvous and getting back. If that's so significant
       | that the Earth launch cost is trivial then the delta-V budget is
       | so huge, it must make the endeavour even more uneconomical.
       | 
       | I believe humanity's future is in a Dyson Swarm. There are simply
       | too many advantages. This is a deep topic. The question is how do
       | you bootstrap that? Where do you get raw materials?
       | 
       | I don't think it's from asteroids. I very much suspect it's from
       | a larger body and my money is on Mercury. Why? On pretty much any
       | body in the Solar System you're living underground so Mercury is
       | at no disadvantage here. It has no atmosphere. That's an
       | advantage. Mars's super thin atmosphere is the worst of both
       | worlds. Additionally, Mercury is metal rich and due to its
       | proximity to the Sun, energy is abundant (ie solar power).
       | Interestingly, it has a higher orbital speed than Earth (47km/s
       | vs 30km/s). That's really interesting because it's free velocity
       | to leave the Solar System.
       | 
       | Resources on EArth are so ridiculously cheap. You can mine iron
       | ore for a few dollars a ton at scale. You can convert it into
       | steel really cheaply too (again, at scale). Doing anything in
       | space requires having truly stupendous amounts of cheap energy
       | available.
        
         | ck2 wrote:
         | There are neutron stars that create chunks of gold and platinum
         | larger than the size of earth itself.
         | 
         | Highly doubt such chunks are floating around our solar system
         | but it's an amusing thought that one day hundreds of years from
         | now we could nudge a (much) smaller chunk into orbit or park it
         | in a Lagrange point and shave off pieces to return to earth.
        
         | julius wrote:
         | Mercury sounds interesting. Requires a certain scale though
         | (gravity is a bitch).
         | 
         | Considering just the initial mining and construction, bodies
         | with low gravity and proximity to the earth feel like an
         | efficient starting point, right? I always thought the moon
         | would be a good place to bootstrap the first few thousand space
         | habitats.
         | 
         | Your point about energy will probably be the biggest deal.
         | Wondering how complicated it would be to ship a bunch of
         | nuclear reactors to the moon. There seems to be quite a few
         | companies working on small, "mass produced" reactors currently.
        
         | ikekkdcjkfke wrote:
         | Send a piece of lead in orbit around the sun so it heats up but
         | not melts, when it comes around heat some water to steam. Free
         | power!
        
           | __MatrixMan__ wrote:
           | Once all of your water is steam, how do you get it back into
           | a liquid phase so that you can do it over again?
           | 
           | Or so that you can do other things, like drink it...
        
           | marcosdumay wrote:
           | The internet is a messed-up place, because as much as I'm
           | convinced this is a joke, I'm also certain somebody could
           | write the same comment in all seriousness and think they are
           | making a great discovery.
           | 
           | We can't even just laugh.
        
         | patall wrote:
         | In terms of delta-v, the asteroids are much closer to us than
         | mercury. A small one in the belt is like delta 1.5km/s from
         | earth escape, versus 11km/s to mercury. Heck, the Mars moons
         | are technically closer to us than 'our' moon. (Overview i.e
         | deltavmap.github.io/)
         | 
         | And the sun is a gravity well. Mercuries higher orbital speed
         | will not help you leave the solar system. In fact, it is the
         | other way around.
         | 
         | Oh, and solar cells are already crazy good. With all the space
         | you have out there, higher energy density on mercury will be
         | very marginally important.
        
         | __MatrixMan__ wrote:
         | re: delta V, the chaotic nature of orbits involving many bodies
         | means that a very well-timed nudge ought to be sufficient to
         | move certain asteroids quite a long distance for "free". So the
         | problem becomes finding the right asteroid, and the right time,
         | and the right nudge vector. More about computation than rocket
         | fuel: the deeper into that chaotic system we can penetrate, the
         | less we have to spend on influencing it.
         | 
         | You've also got to slow it down when it gets to where your
         | smelters are. For that I'd propose we just let it smash into
         | the moon and then mine it on the surface. We can alternate
         | which sides we smash into in order to prevent the moon's orbit
         | from changing significantly.
         | 
         | Of course you still need to provide the initial nudge, which
         | ain't nothing, but it's a far cry from towing an asteroid or
         | towing a smelter.
        
         | theptip wrote:
         | A medium-sized asteroid identified had something like $3T of
         | titanium on it. Of course, that's gross value and you can't
         | clear your supply at that price. But even if it costs hundreds
         | of billions to extract you should be able to net a profit.
        
       | luqtas wrote:
       | breaking news: asteroid mining company mismatch calculus and the
       | rock hits a rural city in Texas
        
       | kibwen wrote:
       | Asteroid mining only makes sense for constructing things in
       | space. For applications here on Earth, the logistics of both
       | leaving and re-entering the gravity well mean that it will never,
       | ever be economical for anything other than materials that
       | literally don't exist on Earth. Bringing platinum and gold from
       | asteroids to Earth doesn't make economic sense, let alone iron.
        
         | Teever wrote:
         | But once you have that infrastructure in space that can mine
         | and construct in space won't that greatly shorten the supply
         | chain for asteroid mining and bring the cost down?
         | 
         | It seems to me that when people make the kind of argument that
         | you're making they're forgetting to price the negative
         | externalities that Earth based mining cost our society via
         | environmental damage.
         | 
         | If the environmental damage and species decline that we're
         | experiencing from our planet-side economic endeavours were
         | properly priced in space based manufacturing and asteroid
         | mining would look a lot more attractive.
        
           | paulryanrogers wrote:
           | The key to manufacturing is humans. Robots help yet need a
           | lot of human maintenance. Human-free spacecraft require a lot
           | of lead time and still begin from a human touch on earth.
           | 
           | NEO is too resource starved for it to ever be independent
           | enough to be cheaper than just managing resources better on
           | the surface of Earth.
        
             | im3w1l wrote:
             | Maintanance is hard, but there is a solution.
             | 
             | Design the robots out of materials that can be found in
             | space. Then make them capable of reproduction. Then you can
             | just scrap damaged robots as long as you can replace them
             | fast enough. This also has the benefit that you just need
             | to send up a tiny bootstrap population, but with time you
             | will have quite the formidable workforce.
        
               | paulryanrogers wrote:
               | Doubtful there are enough resources to sustainably
               | maintain much of anything in NEO. Asteroids with
               | significant reservoirs are far apart and navigating
               | between them is fraught.
               | 
               | Also how are the robots going to know what and how to
               | maintain things? Otherwise they must be remote
               | controlled. Yet their sensors break down over time.
               | 
               | Do reproducing robots even exist on Earth? How robust,
               | nimble, and capable are they? Are their inputs found in
               | space?
               | 
               | All that said, I do love the idea of a robot space colony
               | producing useful things, even if all we gain are space
               | probes and knowledge.
        
               | im3w1l wrote:
               | Robot production on earth is entangled with the whole
               | global supply chain. I do believe many of the steps are
               | automatic or semi-automatic.
               | 
               | It's """simply""" a matter of separating taking all those
               | steps and separating them from the whole, packaging them
               | into a bunch of boxes and sending them to space.
               | 
               | So in other words it's incredibly complicated... but
               | possible.
        
               | Teever wrote:
               | You may find this link interesting:
               | 
               | https://en.wikibooks.org/wiki/Seed_Factories
        
               | collingreen wrote:
               | Kind of a hand-wavy solution here - don't worry about
               | maintenance just invent a self replicating universal tool
               | that is either perfectly recyclable or cheap enough that
               | we don't need to worry about their resource costs or
               | cleanup. With that kind of tech nailed down pretty much
               | ANY endeavor sounds very achievable (until the cheap
               | startup version cuts one too many corners and the gray
               | goo scenario begins I guess).
        
               | Teever wrote:
               | But isn't it just the natural progression of innovations
               | like interchangeable parts and assembly line
               | manufacturing?
               | 
               | And isn't it already a thing that we're progressing to
               | with increased industrial output and reduced labour
               | requirements?
               | 
               | This is where we're going, we just need an driver to push
               | us to do it. Space exploration and resource extraction
               | from the asteroid belt/moon to prevent the complete
               | destruction of our environment seems to be as good a
               | driver as any.
        
         | drexlspivey wrote:
         | The space elevator will make bringing cargo to/from earth
         | trivial and it will happen way before asteroid mining (current
         | estimates for it being built is 15-20 years)
        
           | rapsey wrote:
           | Wildly optimistic when there is no known material that can be
           | used to build it.
        
             | drexlspivey wrote:
             | Carbon nanotube is an existing material, manufacturing it
             | at scale is one of the challenges.
        
               | troupo wrote:
               | manufacturing _and_ building anything out of them in the
               | required scale
        
               | Llamamoe wrote:
               | Carbon nanotubes are not even close to strong enough to
               | build a space elevator, that's the whole problem. We have
               | no idea if anything that strong even exists, at this
               | point.
        
               | drexlspivey wrote:
               | > Carbon nanotubes are not even close to strong enough to
               | build a space elevator, that's the whole problem.
               | 
               | Do you have any sources for that? Because from a quick
               | search online I'm seeing that SE requires a tensile
               | strength of 60-80 GPa and the theoretical max strength of
               | carbon nanotubes can reach 150-200 GPa (with a 63 GPa
               | being demonstrated back in 2000)
        
               | adrian_b wrote:
               | Nobody can make a nanotube with a length of one meter,
               | much less with a length of 1 km or of 100 km.
               | 
               | We can imagine a molecular machine that would grow carbon
               | nanotubes like a silkworm grows silk filaments, but we
               | are many decades away from this kind of things.
               | 
               | Moreover, the tensile strength is not all. It must resist
               | to some intentional or accidental collisions, to
               | earthquake waves and so on.
        
               | DennisP wrote:
               | We don't need kilometers. We need lots of 7cm nanotubes,
               | bonded together with epoxy.
               | 
               | http://images.spaceref.com/docs/spaceelevator/521Edwards.
               | pdf
        
               | adrian_b wrote:
               | That paper only presents hope that perhaps adhesive
               | bonding of carbon nanotubes could produce a cable with
               | high tensile strength.
               | 
               | It does not contain any experimental results supporting
               | this hope, because only a strength similar to steel has
               | been obtained.
               | 
               | Perhaps it will become possible to obtain a higher
               | tensile strength than with other materials by this
               | method, but it is likely that this will require longer
               | nanotubes and perhaps some other kind of polymeric resin
               | instead of epoxy. It is very difficult to find anything
               | that has high enough adhesion to carbon.
        
               | DennisP wrote:
               | Sure, the material had not been produced yet, and still
               | hasn't. Getting all those long nanotubes to line up
               | parallel is another of the hard parts. It's just a
               | theoretical result.
               | 
               | A key part of the design is for the glue to have a low
               | enough melting point, so if the cable breaks, it melts on
               | reentry and you don't get lots of little fluttery bits
               | instead of a big super-strong cable wrapping around the
               | planet.
        
               | DennisP wrote:
               | Here's a NASA-funded study from the early 2000s, arguing
               | that a space elevator could be built as a paper-thin
               | ribbon at least a meter wide, composed of carbon
               | nanotubes 7cm long, bonded together with epoxy.
               | 
               | http://images.spaceref.com/docs/spaceelevator/521Edwards.
               | pdf
               | 
               | The study also addresses lots of other engineering
               | issues. This work sparked a lot of subsequent R&D that is
               | still ongoing. We're not yet able to actually make the
               | ribbon described in the study, but we're getting there.
               | 
               | Then again, if you're willing to rely on dynamic support,
               | a minimal orbital ring could be built with materials we
               | have today:
               | 
               | https://en.wikipedia.org/wiki/Orbital_ring
        
           | theptip wrote:
           | Tether / skyhook seems a more plausible option.
        
           | Ekaros wrote:
           | 15-20 years? I would doubt that range if the process was
           | started yesterday. Any reasonable complex project of closing
           | that scale takes longer time than that. And those have no
           | real unknowns.
        
         | IshKebab wrote:
         | I dunno, Dragon's return capacity is 3000kg which is about
         | $240m... I think if there _was_ a giant sack of pure gold bars
         | up there it would be economically viable. The problem is there
         | isn 't. No way are you going to be able to refine it in space
         | either.
        
           | kibwen wrote:
           | Indeed, I'm referring to the cost of the whole operation,
           | including all the bits where you need to develop and deploy a
           | fully-autonomous robotic mining operation a zillion miles
           | from anywhere.
        
           | __MatrixMan__ wrote:
           | It might not be so hard to do because space is such a good
           | insulator. You could get two chunks spinning on a tether and
           | use a solar pumped laser to heat them. It would be a sort of
           | melting-point chromoatograph where you'd get different
           | materials melting out at different times. Cooling the
           | collected material would be expensive, but you'd end up with
           | most of the gold all together in one stratum of the result.
        
           | theptip wrote:
           | Why would you return the materials in Dragon? You can build a
           | simple glider from space-side materials. The return trip is
           | way easier than getting out of the gravity well. You don't
           | even need crew.
        
             | Teever wrote:
             | Bonus points if you design the glider in such a way that it
             | is covered in some sort of ablative material that helps
             | mitigate climate change after it burns off keeping the
             | mined material from doing so to maximize material return.
        
             | Ekaros wrote:
             | Return trip is double the complexity as first you need to
             | get there. And then you need to slowdown to get back here
             | as into orbit. Getting off the Earth is somewhat solved.
             | But getting there and back at scale is not really done.
        
             | IshKebab wrote:
             | You can't glide back to the surface. Kind of feels like you
             | should be able to but it doesn't work out like that. If it
             | did then that's how all spacecraft would descend.
             | 
             | Scott Manley did a good video about it.
             | 
             | https://youtu.be/5kl2mm96Jkk?si=Uf9ntP6R39SJrVBm
             | 
             | Skip to 3:45 for your exact "well meaning suggestion from
             | people who aren't rocket scientists".
        
           | fnordpiglet wrote:
           | Smelting using focused solar radiation against a spinning
           | carbon crucible would be cheap, mechanically simple, and
           | effective. I'm not sure why you think you can't refine in
           | space.
        
             | bartonfink wrote:
             | Because right now it's not even research, let alone
             | economical. This isn't Stellaris, this is real life.
        
               | fnordpiglet wrote:
               | I see, so when pursuing future technologies we should
               | stick with what we know? We typically research what's
               | achievable in the near future, however the mechanics for
               | purifying heavy metals with centrifugal forces isn't new
               | fwiw. It's how we made atomic bombs.
        
               | bartonfink wrote:
               | So you agree that your earlier suggestion that zero g
               | solar centrifuge smelting is "cheap, mechanically simple,
               | and effective" was basically a pipe dream straight from
               | your ass? You just compared it to the fucking Manhattan
               | Project.
        
             | adrian_b wrote:
             | Smelting is for extracting metals from oxides or sulfides.
             | It can be used on the Moon or on Mars.
             | 
             | It does not work for asteroid mining.
             | 
             | There you have just pieces of iron with a low content of
             | alloying elements.
             | 
             | Among the alloying elements, nickel is the most abundant
             | (17.3 times less than iron), then cobalt (20.9 times less
             | than nickel), then germanium (20.4 times less than cobalt).
             | 
             | The precious metals that would justify the mining operation
             | are present as a few grams each for a ton of iron.
             | 
             | Melting the alloy will never separate the metals by itself.
             | 
             | However perhaps some kind of floating zone melting could
             | enrich the proportion of precious metals in a part of the
             | iron, but it is very unlikely that a high enough enrichment
             | could be achieved by a reasonable number of zone melting
             | passes.
             | 
             | On earth the cheaper metals could be dissolved by an acid
             | solution, but on metallic asteroids you have neither water
             | nor acids.
             | 
             | The SciFi solution would be to vaporize and ionize the
             | metal alloy and separate the metal ions by their specific
             | charge, like in mass spectrometry.
             | 
             | This would need a lot of energy, but at least it does not
             | need reactants and it is the only method that achieves
             | almost perfect separation.
             | 
             | However for now, the throughput of such a ionic separator
             | is extremely small, too small for industrial production.
             | Perhaps it will become possible to scale such ionic
             | separators to acceptable productivities.
        
               | fnordpiglet wrote:
               | Yes I was actually thinking of a gaseous centrifuge
               | process. It would require turning the metals into a gas
               | yet not ionizing them and venting the iron gas into space
               | leaving an ever enriched gold. Realistically you don't
               | need to enrich to total purity.
        
               | adrian_b wrote:
               | Unfortunately that does not work, because these metals
               | are among those with the highest boiling points, even at
               | very low pressures (which is why the oldest solid objects
               | that have formed in the Solar System, at its very
               | beginning, when it was still very hot, have been
               | refractory grains of platinum-group metals with tungsten
               | and rhenium; their condensation has been followed by that
               | of refractory minerals with high content of oxides of
               | aluminum, calcium, titanium and zirconium; and only after
               | additional cooling by the mainstream condensation of
               | silicates and iron alloy).
               | 
               | There are no materials from which you could make a
               | centrifuge for gaseous osmium and iridium.
               | 
               | Vaporizing the input metal with an electron beam and
               | ionizing the vapors allows after that contactless
               | interaction with the ions, using electric fields and
               | magnetic fields, guiding them into separate condensation
               | chambers (which need strong cooling).
               | 
               | The ionic current of such separators must be increased
               | several orders of magnitude over those currently
               | existing, for this to become a viable separation
               | technology.
        
         | alemanek wrote:
         | If any of these asteroids have water ice buried that might be a
         | good start. Easier to refine water and carbon into methane for
         | fuel depots in space than other applications. Also drinking
         | water, splitting for hydrogen or just use the ice as a
         | radiation shield all are near term applications that don't
         | require lots of supporting infrastructure.
         | 
         | I suspect that near term they might make some decent money just
         | returning small samples for labs to analyze. If they can figure
         | out how to do that economically they can likely survive off of
         | grant money from various government entities. Contracting their
         | asteroid lander for various science missions is also a good
         | opportunity.
        
           | antupis wrote:
           | Yup that is how I would do it. Water sample returns to labs >
           | water mining > platinum/gold/etc.
        
           | prepend wrote:
           | I remember reading an article from back when Blue Origin was
           | a space mining concern that the first thing to grab is water
           | just to supply the space station. Because it's so expensive
           | to take water into orbit and retrieving a comet or something
           | else was fairly cheap and could yield billions of water for
           | use by anyone in orbit.
        
         | __MatrixMan__ wrote:
         | Suppose one of the things you construct in space is a skyhook.
         | The economical way to operate one of those is to bring down as
         | much mass as you bring up, that way the net change in angular
         | momentum is 0. This would change the economics of bringing
         | space-materials down to earth.
         | 
         | That said, we're a long long way from being able to build a
         | skyhook. I'm only objecting to the "never, ever" part of your
         | post.
        
           | kibwen wrote:
           | _> I 'm only objecting to the "never, ever" part of your
           | post._
           | 
           | Sure, let me qualify "never, ever" as having a time horizon
           | of "so long that anyone claiming that you, the eager
           | investor, will see an economic return on this endeavor in
           | your lifetime is secretly banking on breakthroughs in life
           | extension technologies to make that statement technically
           | correct".
        
             | nahkoots wrote:
             | "within your natural lifespan" isn't really a qualification
             | of "never, ever". The two are very different time frames. I
             | think it's good that you're willing to adjust your opinions
             | given new information, but it would be nice if you admitted
             | that you changed your mind based on what MatrixMan said
             | instead of acting like "within your natural lifespan" was
             | your original intent.
        
               | kibwen wrote:
               | Every prediction about the future--this one, every other
               | one ever made, and every other one that will ever be made
               | --is implictly made under the assumption that if the
               | prediction lies beyond the predictor's lifespan, then the
               | predictor will not be in a position to care one whit
               | about the veracity of the prediction when that time
               | comes. My clarification isn't at all motivated based on
               | what the parent commenter said (I find the construction
               | of a skyhook approximately as likely as the construction
               | of a space elevator, which is to say, it will "never,
               | ever" happen), but rather as an explicit clarification of
               | the aforementioned implicit assumption.
        
               | __MatrixMan__ wrote:
               | My trouble with this definition of never ever is that it
               | prevents us from starting on endeavors that may take a
               | long time--a self fulfilling prophecy.
               | 
               | We may never ever mitigate our climate concerns, which
               | obfuscates that it is a choice we'll have made, not an
               | inevitability.
        
               | drdeca wrote:
               | Why does it matter whether their caring about whether
               | their prediction is correct, is done at the time that
               | their prediction is about?
        
               | staunton wrote:
               | What would you say to someone who claims that "never"
               | obviously means "not before the end of this quarter,
               | cause who could possibly care about anything beyond
               | that"?
        
         | hypertele-Xii wrote:
         | Silver is antimicrobial. Gold is highly conductive.
         | 
         | If we had these materials in absurd excess, we could literally
         | build hospitals from silver and the electric grid from gold,
         | and it would be great for our civilization.
        
           | otabdeveloper4 wrote:
           | Gold and silver is less common in space than here on Earth.
        
             | blooalien wrote:
             | https://www.forbes.com/sites/jamiecartereurope/2023/06/05/g
             | o...
             | 
             | You sure about that? Here's just one asteroid made of
             | mostly gold, nickel, and / or iron that's supposedly worth
             | many times more than the entire global economy. Pretty sure
             | that anything we have here on Earth also exists "out there"
             | in _much_ greater abundance than we could ever possibly
             | imagine here on our finite little speck of a planet (except
             | maybe  "life", which we only have absolute _proof_ of here
             | on Earth).
        
               | adrian_b wrote:
               | In the whole Earth the abundances of the elements are
               | similar to the averages of the Solar System, with the
               | exception of some volatile elements, most of them being
               | non-metals, which have been lost in space during the
               | condensation of the Earth and also later.
               | 
               | However the Earth is made of layers with different
               | chemical compositions and many elements are concentrated
               | in layers that are too far from the surface to hope that
               | we will ever reach them. So in the accessible part of the
               | Earth, close to the surface, those elements are seriously
               | depleted.
               | 
               | Some asteroids, unlike the Earth, have never been melted.
               | In that case their composition is homogeneous, similar to
               | the averages of the Solar System. Other asteroids are
               | broken parts from the cores of bigger planets, so they
               | have a composition like in the Earth at very high depths.
               | 
               | However, in the latter kind of asteroids the useful
               | metals are dissolved as tiny percentages in an iron-
               | nickel-cobalt-germanium alloy. This will make their
               | extraction incredibly energy-consuming. On Earth such
               | metals have been separated during millions of years from
               | their surrounding minerals and they have been accumulated
               | as native nuggets or metallic sulfides that are very easy
               | to process for their final separation and purification.
               | 
               | With the alloy that exists in planet cores and asteroids
               | nobody has demonstrated an efficient separation method
               | yet. The laboratory methods used for such separations use
               | huge amounts of water and acids and they will be
               | impossible to implement on an asteroid. Carrying raw
               | metal from asteroids, which is almost completely iron,
               | would also increase the costs tremendously.
               | 
               | So it is absurd to even consider asteroid mining before
               | demonstrating a method that can extract the metals from
               | iron at the mining sites and with a minimum consumption
               | of energy and of non-recyclable reactants.
        
               | yowzadave wrote:
               | > gold, nickel, and / or iron that's supposedly worth
               | many times more than the entire global economy
               | 
               | You hear these statements sometimes about asteroid
               | mining, and they betray a misunderstanding of the way
               | economies work. The reason gold/etc. is expensive is
               | because it is scarce. If we suddenly have an abundance of
               | these materials, then they will be cheap. The intrinsic
               | value of these metals is not worth multiples of the
               | global economy.
        
               | DennisP wrote:
               | For precious metals that doesn't necessarily mean it's
               | not worth going to get them in large quantities. Aluminum
               | used to be more precious than gold. Now we make airplanes
               | out of it.
        
               | nsxwolf wrote:
               | Soda cans too!
        
               | beerandt wrote:
               | It's a pretty good example with the difference being
               | energy to retrieve vs energy to refine.
               | 
               | Even with/if there's a 'flood the market' eventuality,
               | you'd have approx multiple generations for the market to
               | grow and mature, improving the associated technologies
               | along the way, and wealth generated orders beyond the
               | Carnegies Rockefellers and Vanderbilts combined.
        
               | dhosek wrote:
               | I've had an idea for a sci fi story lurking in the back
               | of my head of an earth-based cartel sabotaging space
               | mining to preserve the value of their precious metals.
               | The catch is being able to communicate the economics in a
               | way that's both accurate and entertaining.
        
               | blooalien wrote:
               | As long as you double-check it's work, you could always
               | ask an LLM for help with some of that, maybe? I'd install
               | something local like Ollama or somesuch and download one
               | of the larger more popular more recent models and give it
               | an appropriate system prompt related to being a "writing
               | assistant" or something like that. Then bounce ideas off
               | it and maybe throw a few related articles at it for
               | "context" to work with. It's one of the things a lotta
               | recent LLMs are actually useful for and somewhat good at.
        
               | dhosek wrote:
               | Nah, I'm the kind of writer who views using a thesaurus
               | as cheating. I have no interest in LLM nonsense for my
               | writing.
        
             | notfish wrote:
             | What? Carbonaceous chondrites (the toyota corolla of
             | asteroids) are like .1ppm gold, whereas Earth's crust is
             | ~0.005ppm
             | 
             | https://pubs.usgs.gov/circ/1968/0603/report.pdf
        
               | adrian_b wrote:
               | Carbonaceous chondrites are bodies that have never
               | aggregated into a big planet, so their chemical
               | composition is close to the average composition of the
               | Solar System.
               | 
               | They are extremely numerous, but most of them are
               | extremely small. Changing the spaceship orbit to catch
               | one of them, which might have a few tons only in rare
               | cases, will provide only a few grams at most of useful
               | elements, far too little for the energy spent to achieve
               | this.
               | 
               | Mining a big asteroid that is a fragment of the core of a
               | former bigger planet has much more chances to be
               | worthwhile, but even for that nobody has gives any
               | suggestion yet for how to separate the mined metals from
               | iron and nickel at the extraction place, otherwise the
               | transportation of the raw alloy would also need too much
               | energy.
        
             | adrian_b wrote:
             | The average content of gold and silver and of platinum-
             | group metals is very similar in the whole Earth and in the
             | rest of the bodies of the Solar System.
             | 
             | Nevertheless, in the crust that covers the _surface_ of the
             | Earth, the abundances of gold and silver and of platinum-
             | group metals are many orders of magnitude lower than their
             | average abundances in the Solar System.
             | 
             | For instance most of the silver has remained in deep parts
             | of the mantle when the crust has formed, so silver is 11
             | times less abundant at the surface of the Earth than in the
             | Solar System.
             | 
             | Gold and the platinum-group metals have gone to even higher
             | depths, in the iron kernel. So at the surface gold is
             | almost 300 times less abundant than in the Solar System,
             | rhenium almost 600 times and nickel more than 900 times
             | less abundant than in the Solar System, palladium around
             | 3000 times, platinum and ruthenium around 5500 times and
             | osmium and iridium around 50000 times less abundant than in
             | the Solar System.
             | 
             | Similar numbers apply to all of the 8 planets that are big
             | or medium-sized and also for some of the small planets and
             | big satellites, because all these have been melted at some
             | point in their history, when all the metals with high
             | affinity to iron or sulfur have gone to inaccessible depths
             | below the surface of those planets.
             | 
             | In the outer parts of the Solar System, the bodies are
             | covered by thick layers of ice, but for the 4 inner planets
             | the silicate crust that we see covering their surface is
             | similar to the slag that forms at the surface of the iron
             | smelted in an iron furnace and it is similarly depleted in
             | the metals with low electropositivity.
        
             | fnordpiglet wrote:
             | Thank goodness there's a lot more space than earth then!
        
           | coryrc wrote:
           | Gold is a worse conductor than copper. Silver is slightly
           | better per volume but worse per mass.
        
         | BobaFloutist wrote:
         | Surely reentering is very much not the problem?
        
           | kibwen wrote:
           | Re-entering is a very large problem. Say you've got a few
           | thousand tons of material hurtling towards Earth. How do you
           | get it down to the surface in a useful way? You're not just
           | going to shotgun it raw into the ocean, because then you
           | still have to retrieve it somehow. You're not going to land
           | it with rockets, SpaceX-style, because the fuel costs would
           | be astronomical. You're not going to land it with a short
           | atmospheric drag followed by parachutes, Apollo-style,
           | because the weight makes the energies too great (the Apollo
           | command module weighed about 6 tons upon re-entry). You're
           | going to need something much more sophisticated, Space
           | Shuttle-style, but on a grander scale than ever, and you're
           | going to need to bear the cost of putting that thing back
           | into orbit every time, or you're going to need to develop
           | something brand-new (like a HUGE inflatable re-entry vehicle)
           | or something that exists in the realm of sci-fi (like a space
           | elevator).
        
             | tzs wrote:
             | Does it have to be _hurtling_ toward Earth? How about first
             | parking it at the L4 or L5 Earth-Sun Lagrange point, and
             | then nudging it so it leisurely meanders toward Earth
             | instead of hurtles toward Earth?
             | 
             | That would enter the atmosphere orders of magnitude slower
             | than meteors do. Would that be enough for it to largely
             | survive the fall to the surface either stay largely intact
             | on impact or break up but the pieces would all be in the
             | same general area?
        
               | DennisP wrote:
               | Heh that's an interesting point. It doesn't have to orbit
               | the Earth, so it doesn't necessarily have lots of lateral
               | velocity to burn off. It'd be interesting to work the
               | numbers for just matching the Earth's velocity around the
               | sun, at a distance of a few hundred kilometers.
               | 
               | Edit: based on a quick chat with Claude Sonnet, reentry
               | velocity would be about a fourth as high, but getting to
               | that initial orbit in the first place makes the whole
               | project significantly harder. But maybe if ablation from
               | reentries became an environmental problem, and deep-space
               | propulsion got really good, it'd be worthwhile.
        
               | kibwen wrote:
               | While the interplanetary transfer network is real (https:
               | //en.wikipedia.org/wiki/Interplanetary_Transport_Netwo...
               | ), getting a payload onto the network itself requires a
               | large and varying amount of energy based on where your
               | asteroid is located. And then once you've successfully
               | gotten your giant rock of solid platinum to some Earth-
               | Sun Lagrange point, you still need to manage its descent
               | to Earth, and beyond the technical difficulties of trying
               | to steer it precisely, the superpowers of the world are
               | unlikely to be peachy keen on the idea of a private
               | company having global orbital bombardment capabilities,
               | which is going to be a political headache of its own.
        
             | DennisP wrote:
             | Starship has a return capacity of 50 tons.[0] If you have
             | 5000 tons of material to return, that's a hundred Starship
             | flights.
             | 
             | I wouldn't expect asteroid mining to be viable until we
             | have Starship or something like it at scale, doing
             | thousands of launches per year. If most of those flights
             | return empty, then that's a lot of cargo space already
             | available.
             | 
             | Starship uses $1 million in fuel to launch 100 tons to LEO,
             | so half that much should be plenty to take 50 tons back
             | down. But Starship's propellant mass for launch is 2600
             | tons[1] so that'd be up to thirteen launches to put the
             | landing fuel in orbit. Actually it'd be less, since a lot
             | of the orbital velocity is burned off by atmospheric
             | breaking, not sure how much.
             | 
             | Ideally though, get the fuel from the same asteroids you're
             | mining already. Starship uses methane, so you're just
             | looking for water ice and carbon, both abundant in
             | asteroids.
             | 
             | At current prices, 5000 tons of gold is worth about $400
             | _billion_ , so it's not obvious that this wouldn't be
             | economical. The world mines about 3000 tons of gold
             | annually and the price of gold has still been going up, so
             | if our asteroid miner returns a couple thousand tons per
             | year it might not crash the price too badly.
             | 
             | [0] https://space.skyrocket.de/doc_lau/super-heavy-
             | starship.htm
             | 
             | [1] https://en.wikipedia.org/wiki/SpaceX_Starship
        
               | kibwen wrote:
               | Gold is the worst example because the price of gold is
               | almost 100% based on its scarcity. Doubling the supply of
               | gold would just cause the price to roughly halve.
               | Hilariously, if you actually _had_ the capability to
               | inundate the world with gold, you 'd find it much easier
               | and still extremely profitable to extort the people who
               | own gold to pay you _not_ do so.
        
               | DennisP wrote:
               | You'd make a lot of money on the way to doubling the
               | world's supply. 3000 tons annually just doubles how much
               | we mine, not how much we have; that's more like 190,000
               | tons. And even if you doubled the total supply instantly,
               | you'd now own half the current value of the world's gold,
               | which would be about $6 trillion.
               | 
               | And of course gold has all sorts of really useful
               | properties, so long term, it'd be worthwhile to make it
               | abundant and cheap.
        
         | thebruce87m wrote:
         | Might make sense for Mars or a moon base too.
        
         | theptip wrote:
         | I don't think this is categorically true. A couple obvious
         | options are constructing titanium gliders to land materials on
         | earth, and de-orbiting incoming metal loads with a space tether
         | to provide inertia that can then be used to launch planetary
         | loads to orbit.
         | 
         | It's true that the relative value of these materials will be
         | higher in space (since your alternative is lifting it out of
         | the gravity well) but there may be so much supply that you can
         | saturate the space market and justify the extra transport cost
         | to sell it on earth too.
        
         | datadeft wrote:
         | Citation needed. Moving the biggest polluters from Earth to
         | space makes a lot of sense. I am not sure about economic
         | realities.
        
           | kibwen wrote:
           | To be clear, I think there's a lot of reasons to do cool
           | things in space (Moon base, etc.). However, we're kidding
           | ourselves if we think one of those reasons is "make a profit
           | based on the intrinsic economic value of the endeavor".
        
         | tejtm wrote:
         | This neglects the cost of extraction. In particular, the most
         | rare (and therefore precious) commodity in the solar system and
         | indeed the universe is the 4 billion year old bioreactor we
         | refer to as "topsoil".
         | 
         | Getting all the other elemental material we need without
         | screwing that up will be a win for our descendants.
        
           | nradov wrote:
           | The topsoil lost from mining is miniscule compared to other
           | causes. Most mines aren't even located in places that could
           | be used as productive farmland.
        
         | solardev wrote:
         | Can't we just shape the mined platinum into rods and drop them
         | into the oceans from orbit? Or onto rival mining companies, for
         | that matter?
        
           | vosper wrote:
           | Often referred to as Rods from God, but Syndicate Wars had
           | the better name: Satellite Rain.
        
         | tonetegeatinst wrote:
         | Rare earth metals might be a good use case....say the stuff
         | used in cytalitic converters etc
        
           | daymanstep wrote:
           | Rare earth metals are not actually rare.
        
         | dyauspitr wrote:
         | I think it makes a lot of sense. You leave the earth light and
         | you return heavy and have a gravity assist to return it to
         | earth for free.
        
         | jessriedel wrote:
         | Bringing stuff down from space is not that expensive with
         | reusable systems like Starship, and this is even more true if
         | you don't need to soft land it (i.e., spray an ablative on a
         | huge rock of precious metals and let it re-enter). Asteroids
         | can be re-directed to Earth for delta V costs that are quite
         | small. There's no fundamental physics barrier here.
        
       | therediterator wrote:
       | The cost of getting the asteroid to orbit, transportation (back
       | and forth), and mining it would be too much. Even if we do this,
       | keeping in mind that we can find some elements that we are aware
       | of, I think it is way more important for humanity overall to
       | execute this mission because there is always an upside that we
       | can discover something that is much more valuable just like the
       | company can sell the piece of just an asteroid as a souvenir.
        
       | inamberclad wrote:
       | I recently did an interview with them and found their perspective
       | to be a little... flippant? A bunch of screw NASA, we sleep in
       | the office, etc etc. I admit that I only spoke with one person in
       | the company but it was enough that I realized it wasn't the work
       | environment I wanted for myself. Regardless, I wish them all the
       | best.
        
       | devit wrote:
       | Using the rocket equation, it is possible to compute the ratio
       | between the $kg launch cost and $/kg material sell price that
       | would make it economical.
       | 
       | Based on my calculations, with optimistic assumptions (including
       | the asteroid being made solely of the desired material), you need
       | 5 Falcon 9 launches and in-space assembly to bring back one ton
       | of material, which would require selling the material for
       | 350k$/kg for parity. But gold is only 80k$/kg, platinum is
       | 30$/kg, etc.
       | 
       | Doesn't look feasible with current technology.
        
         | Teever wrote:
         | Can you share your calculations and assumptions that go into
         | them?
        
         | withinboredom wrote:
         | > Doesn't look feasible with current technology.
         | 
         | If you don't pay the demanded price before it arrives in orbit,
         | it will be delivered a full speed on your lawn. Your entire
         | city will be destroyed.
        
       | AwaAwa wrote:
       | This gives me the same vibes as OceanGate's Titan, and Boeing's
       | Starliner capsule.
       | 
       | Better these two as a role model than Theranos though.
       | 
       | Obviously the lack of any squishy humans that need to be part of
       | the process makes it less of an issue when nothing comes of it.
        
       | MarketingJason wrote:
       | I'm no rocket scientist, but to me it makes sense to try and
       | redirect asteroids to enter our atmosphere. The only thing I'd
       | seek to "mine" on the asteroid is H2O, Hydrogen, or something
       | that could be immediately converted to power/propulsion by the
       | unit-itself.
       | 
       | I guess one risk would be introducing unknown biological or
       | chemical nastiness. Another would be how precise we could be to
       | target open ocean/desert/etc.
        
         | dyauspitr wrote:
         | That's insanely irresponsible. Even if everything goes
         | perfectly you're going to have volcano tier dust plumes
         | altering the local climate and in the worst case you could kill
         | millions of people by wiping out entire cities.
        
       ___________________________________________________________________
       (page generated 2024-08-24 23:01 UTC)