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Prospecting the Solar System


Diche Bach

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1 hour ago, DerekL1963 said:


That's easy to say, more difficult to do, especially if you're running on borrowed money and have to pay interest.  And you have to recoup not only the direct costs and overhead, but also repay the capital costs before you can start turning a profit.

And that's the big problem right now - we simply don't have the information to assign reasonably reliable values to any of those.

You would presumably go on venture capital, with investors that can tolerate long investments. But you would not sell below a level to make a profit, unless the entire venture went belly up and you need to scrap the whole thing entirely. Now, because it's high risk I would think you'd need a quick turnaround, but once you have the material safely on earth (talk about carefully planning reentry) you can sell it all to an investor looking for a long term safe investment, who would take their time selling it off and raking in a profit. 

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On Tuesday, October 11, 2016 at 4:20 PM, DerekL1963 said:


Mined and processed and returned to earth (in significant quantities).  The sticking point is that of the three, we have no idea how to do the first two - and machinery for doing so tends to very large and very heavy.

At a value of multiple trillions of dollars for a single asteroid (for reference, NASA's annual budget is 18-19 billion $, and $4 trillion is nearly the annual US budget), you wouldn't need to purify the minerals.  It would literally be profitable just to cut the asteroid up into chunks that you send down to Earth unrefined.  Especially if the recovery capsules were, reusable, and could be re-launched back to orbit on reusable rockets...

Cutting an asteroid up into lots of small chunks wouldn't be easy- but it's certainly feasible.

 

Regards,

Northstar

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5 minutes ago, Northstar1989 said:

At a value of multiple trillions of dollars for a single asteroid (for reference, NASA's annual budget is 18-19 billion $, and $4 trillion is nearly the annual US budget), you wouldn't need to purify the minerals.  It would literally be profitable just to cut the asteroid up into chunks that you send down to Earth unrefined.  Especially if the recovery capsules were, reusable, and could be re-launched back to orbit on reusable rockets...

Not unless the ores are of considerably higher concentration than they here on earth...  But if you're down in the single-digit-ounces-per-ton range, I don't think there's anything that valuable.  It doesn't matter what the total value of the resource is - the only thing that matters is what it costs to fetch it, refine it, and deliver it as compared to what it can sell for on the open market.

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On 10/11/2016 at 7:23 PM, Diche Bach said:

This is the essence of my interest in this topic, and if anyone either read the original post, or goes back and tries to make sense of it this may be clear.

Right now, apart from communications satelllites (where costs have apparently gone higher for infrastructure and capital investments, despite the fact the services that infrastructure provides have got cheaper) "space does not make money" for anyone, other than the small fraction of humanity who have jobs in space stuff. The only economically useful things "space" is good for seem to be: 1. satellite services (primarily data transmission, but remote sensing too I suppose); 2. science, which does have some profitability to it as a result of patents, marketing, etc.

Guys like Elon supposedly have this "vision" to make an audacious impact that accelerates humanity into full-fledged "spacefaring species" status. That is a laudable goal, but I don't think putting the cart before the horse--or rather putting manned-expeditions to Mars before the mastery of robotic mining armies--makes much sense. No matter how romantic any of us are about space, our species is never going to "get out there" in any appreciable numbers based simply on "romantic notions." There have to be pragmatic reasons for the huge investments and risks to be taken, and there have to be successes that will prompt competition for a piece of that risk/reward deal. This is the reason any species expands into new niches and it is the reason we humans have colonized the entire planet. Space will be no different, no matter how appealing Elon's vision might be. I'd bet on the quiet engineering firms like Planetary Resources who are actually trying to figure out how to make money from stuff out there. They are the real heroes because once they prove it can be done, throngs will be following them and they will have done what Elon claims he wants to do.

There is very little money to be made, nowadays, from raw materials. Your profit lies in bulk, and there's a reason that the wealthiest people aren't mining or farming magnates.

People largely make money off of people. Either this changes, or the biggest profit from a martian colony is the increased consumer base. Or, if you want to be cynical about it, it's the perfect place to perform experimentation that is too dangerous or too illegal to perform on Earth, iron out the kinks, and then benefit from the finished product back here.

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6 hours ago, DerekL1963 said:

Not unless the ores are of considerably higher concentration than they here on earth...  But if you're down in the single-digit-ounces-per-ton range, I don't think there's anything that valuable.  It doesn't matter what the total value of the resource is - the only thing that matters is what it costs to fetch it, refine it, and deliver it as compared to what it can sell for on the open market.

My point is that the costs of fetching those resources from LEO down tobthe syrface really aren't that high.  It doesn't matter what the concentrations are if the wlements within that ore are valuable enough.

With a reusable capsule system (the capsules wouldn't even need to be pressurized), the costs to bring that ore down to the surface would become comparatively very low indeed.  We're talking hundreds or thousands of re-uses each year (for a single large asteroid) of a small capsule launched atop a reusable rocket- something no larger than the Falcon 9 at most...  With enough launches/re-uses each year, the economies of scale really start to add up...

And, as any veteran KSP player is well aware, many Near-Earth Objects would require *very* little Delta-V to bring to an aerocapture trajectory in the first place (less than 100 m/s).  So the fuel costs of moving an asteroid to LEO could be very low- less still if you're willing to make shallow aerobraking passes that leave Earth's SOI a few times (possibly with Lunar gravity-braking as well) before finally capturing such an asteroid.

 

Regards,

Northstar

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51 minutes ago, Northstar1989 said:

My point is that the costs of fetching those resources from LEO down tobthe syrface really aren't that high.

Yes, the costs of fetching unrefined resources down from LEO are very high compared to the value of the material.  At current prices, iridium fetches $650 a troy ounce, $20k per kilogram.  If the asteroid is 5% iridium/metric ton (50,000 times higher than the the actual average of .5ppm in meteorites) - that's $100k per 1 ton chunk you bring back.  You probably can't even fuel the booster for that, let alone the balance of your operational costs (even at your handwaved re-use rate).

Seriously, the numbers absolutely do not add up when you start running them.

So to make it work, you need either something that's freakishly expensive and in demand (and which will remain so even when you start selling*), or a freakish drop in the cost of the energy required to fetch the raw ore.

* And it absolutely has to retain those prices when you start selling - because your whole scheme relies on flights by the gross lot to cover your initial capital outlay.

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7 hours ago, DerekL1963 said:

Yes, the costs of fetching unrefined resources down from LEO are very high compared to the value of the material.  At current prices, iridium fetches $650 a troy ounce, $20k per kilogram.  If the asteroid is 5% iridium/metric ton (50,000 times higher than the the actual average of .5ppm in meteorites) - that's $100k per 1 ton chunk you bring back.  You probably can't even fuel the booster for that, let alone the balance of your operational costs (even at your handwaved re-use rate).

Seriously, the numbers absolutely do not add up when you start running them.

So to make it work, you need either something that's freakishly expensive and in demand (and which will remain so even when you start selling*), or a freakish drop in the cost of the energy required to fetch the raw ore.

* And it absolutely has to retain those prices when you start selling - because your whole scheme relies on flights by the gross lot to cover your initial capital outlay.

Cite your figures.  The estimated value of these asteroids in the trillions per-asteroid was cited by an earlier poster- you will have to cite your claim that Iridium sells for only $20k per kg for it to be believable...

However even at that cost the numbers *do* add up, and it *would* it would be profitable...

SpaceX *currently* sells payload capacity at $2719/kg, according to Wikipedia, and has announced a 30% reduction in pricing for the first reusable flights.  However in time, Musk thinks the cost will come down further, eventually reaching under $300/kg (This is the assumed cost all my earlier arguments hinged on).

At $300/kg, you could launch over 64 kg of mass to LEO for each kg of Iridium recovered at a value of $20k/kg price (leaving some margin for refining costs).  Further, it's perfectly reasonable to expect at least a 10:1 or 12:1 mass-ratio for capsule mass to recoverable mass if the capsule is unpressurized, contains the sensitive electronics in a seperate compartment from the payload- which is allowed to reach basically any temperature as long as it doesn't melt, and relies on a propulsive-landing with nothing more than drogue chutes at most...

So, you could launch a 64 kg capsule that recovers 640 kg of ore for less than $20,000 in launch costs if Musk's predictions prove true (and a 64 kg payload would be  in the range of a secondary payload on a Falcon 9- so you might get it to LEO for *even less* than that).  If that capsule were reusable, then the construction costs of the capsule itself wouldn't be astronomical once amortized over many uses (let's say at least 40 per capsule- as you can afford for a capsule or two to fail during reentry/landing), and as long as you recovered at least a kg or two of Iridium for each 640 kg of ore, you'd make an operating profit...  The key would be to perform operations on a large enough scale to pay back the initial R&D costs and those of getting the asteroid to LEO in the first place...

As you can see, there's definitely a slim margin to make a small profit here if the assumptions that I outlined in my earlier post to begin with (that Falcon 9 reusability works and is cheap) pan out.  It could be that the Falcon 9 cost estimates Musk has been making don't pan out, but that's not the same as the numbers here not adding up if they *do*.

Respectfully  I don't appreciate your constant weakly-supported criticisms of anything innovative I argue or suggest Derek, and would love to see a little more open-mindedness from you.  Between yourself and Nibb, I get no end to constant (often factually-inaccurate) criticisms and pessimism on a *variety* of posts on this subforum, and haven't for the past two years of posting here...  Do what you will, I'm just voicing my feelings about your behavior, and letting you know I'm very unhappy about it.

 

Regards,

Northstar

EDIT: So Elon thinks his Mars Colonial Transporter will be able to put payload on Mars for $140k/ton (that's IMHO both extremely optimistic, and *still* too high for large-scale colonization without government financial assistance, but that's beyond the point...)  That equates to $140/kg to Mars.  If the MCT can achieve THAT, then surely Musk should be able to achieve $300/kg to LEO (which is low enough for a scheme that just relies on recovering raw Iridium ore from an asteroid hauled to LEO to be profitable) with at least *one* of his launch vehicles...

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7 hours ago, Northstar1989 said:

Cite your figures.  The estimated value of these asteroids in the trillions per-asteroid was cited by an earlier poster- you will have to cite your claim that Iridium sells for only $20k per kg for it to be believable...

However even at that cost the numbers *do* add up, and it *would* it would be profitable...

SpaceX *currently* sells payload capacity at $2719/kg, according to Wikipedia, and has announced a 30% reduction in pricing for the first reusable flights.  However in time, Musk thinks the cost will come down further, eventually reaching under $300/kg (This is the assumed cost all my earlier arguments hinged on).

At $300/kg, you could launch over 64 kg of mass to LEO for each kg of Iridium recovered at a value of $20k/kg price (leaving some margin for refining costs).  Further, it's perfectly reasonable to expect at least a 10:1 or 12:1 mass-ratio for capsule mass to recoverable mass if the capsule is unpressurized, contains the sensitive electronics in a seperate compartment from the payload- which is allowed to reach basically any temperature as long as it doesn't melt, and relies on a propulsive-landing with nothing more than drogue chutes at most...

So, you could launch a 64 kg capsule that recovers 640 kg of ore for less than $20,000 in launch costs if Musk's predictions prove true (and a 64 kg payload would be  in the range of a secondary payload on a Falcon 9- so you might get it to LEO for *even less* than that).  If that capsule were reusable, then the construction costs of the capsule itself wouldn't be astronomical once amortized over many uses (let's say at least 40 per capsule- as you can afford for a capsule or two to fail during reentry/landing), and as long as you recovered at least a kg or two of Iridium for each 640 kg of ore, you'd make an operating profit...  The key would be to perform operations on a large enough scale to pay back the initial R&D costs and those of getting the asteroid to LEO in the first place...

As you can see, there's definitely a slim margin to make a small profit here if the assumptions that I outlined in my earlier post to begin with (that Falcon 9 reusability works and is cheap) pan out.  It could be that the Falcon 9 cost estimates Musk has been making don't pan out, but that's not the same as the numbers here not adding up if they *do*.

Respectfully  I don't appreciate your constant weakly-supported criticisms of anything innovative I argue or suggest Derek, and would love to see a little more open-mindedness from you.  Between yourself and Nibb, I get no end to constant (often factually-inaccurate) criticisms and pessimism on a *variety* of posts on this subforum, and haven't for the past two years of posting here...  Do what you will, I'm just voicing my feelings about your behavior, and letting you know I'm very unhappy about it.

 

Regards,

Northstar

EDIT: So Elon thinks his Mars Colonial Transporter will be able to put payload on Mars for $140k/ton (that's IMHO both extremely optimistic, and *still* too high for large-scale colonization without government financial assistance, but that's beyond the point...)  That equates to $140/kg to Mars.  If the MCT can achieve THAT, then surely Musk should be able to achieve $300/kg to LEO (which is low enough for a scheme that just relies on recovering raw Iridium ore from an asteroid hauled to LEO to be profitable) with at least *one* of his launch vehicles...

Progress is always a balance between dreamers and skeptics. Both are required in the end.

Back to this topic, I think the most cost effective solution is to minimize mass you send to LEO and bring back. So, you send up a refiner, re entry pod, and tug. The first trip will involve tug pod and refiner going to an asteroid, where the refiner does its thing (can be a very course refiner, just enrich the ore to 50% or so). The tug brings the pod back, the pod enters the atmosphere. Send the pod back up with fuel for the tug, the tug takes the pod back to the asteroid where the next shipment is likely already ready. Refiner never goes back to LEO, just goes on to the next asteroid when ready.

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9 hours ago, Northstar1989 said:

Cite your figures.  The estimated value of these asteroids in the trillions per-asteroid was cited by an earlier poster- you will have to cite your claim that Iridium sells for only $20k per kg for it to be believable...

o.0  You seriously can't google "spot price of Iridium"?  Let me google that for you

 

9 hours ago, Northstar1989 said:

However even at that cost the numbers *do* add up, and it *would* it would be profitable...

o.0 Did you read the part where my thought experiment was for ore with 50,000 times the concentration known to exist in space?
 

10 hours ago, Northstar1989 said:

Further, it's perfectly reasonable to expect at least a 10:1 or 12:1 mass-ratio for capsule mass to recoverable mass if the capsule is unpressurized, contains the sensitive electronics in a seperate compartment from the payload- which is allowed to reach basically any temperature as long as it doesn't melt, and relies on a propulsive-landing with nothing more than drogue chutes at most...


Which means you need a heat shield.  And protection for the drogues.  And RCS for establishing initial orientation.  And some form of de-orbit system.  And... all the other stuff you simply handwave away.
 

9 hours ago, Northstar1989 said:

Respectfully  I don't appreciate your constant weakly-supported criticisms of anything innovative I argue or suggest Derek, and would love to see a little more open-mindedness from you.


Respectfully, it's strongly supported and well deserved criticism - basic mistakes like the one with ore concentration cited just above amply demonstrate why.

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3 hours ago, DerekL1963 said:

o.0  You seriously can't google "spot price of Iridium"?  Let me google that for you

 

o.0 Did you read the part where my thought experiment was for ore with 50,000 times the concentration known to exist in space?
 


Which means you need a heat shield.  And protection for the drogues.  And RCS for establishing initial orientation.  And some form of de-orbit system.  And... all the other stuff you simply handwave away.
 


Respectfully, it's strongly supported and well deserved criticism - basic mistakes like the one with ore concentration cited just above amply demonstrate why.

The burden of proof is on the person making the claim.  I didn't claim anything based on a specific price for Iridium, but rather on the previously-cited overall value of certain Near Earth Objects, it was *you* who claimed Iridium (which is not the only metal you'd get when trying to cut out Iridium rich rocks from an asteroid- Iridium is frequently found near Platinum, for instance) sells at $20,000/kg and thus needed to cite your source.

Respectfully, that link does absolutely nothing to back up your point.  In fact, it speaks at one point of naturally-occurring uncombined Iridium deposits- so it contradicts it.  The low concentrations of iridium found in some meteorites are not necessarily the same as those found in asteroids.  Iridium is in fact sometimes found as an uncombined element- which would clearly indicate much higher concentrations than 0.5 ppm can be found...  To quote an article from Los Alamos National Laboratory:

"Iridium occurs uncombined in nature with platinum and other members of this family in alluvial deposits."

If Iridium is found uncombined, that would imply that, while its overall abundance may be extremely low, rock sections can be found containing nearly pure Iridium veins- although they would be incredibly rare (and thus, the whole plan hinges on being able to locate asteroids containing such high-purity Iridium deposits in the first place, as opposed to those containing Iridium impurities in other ores).  *Those* high-purity Iridium ores are what you'd recover to Earth's surface without refining- not the entire asteroid.

As for the heatshield, RCS, de-orbit system, those were clearly part of my 1:10-1:12 mass ratio estimate for the capsule as a whole.  The unpressurized chamber holding the ore itself, stuffed with rocks, would have something like a 1:50 or 1:100 mass ratio.  The rest of the mass is for engines, heatshielding, etc.  Your criticism is once again baseless and invalid.

I made no "basic mistakes", although your use of that language is condescending.  Once again, I find your attitude to be rude and condescending, and your criticism very, very weak in its factual basis when there is any to speak of.  I am offended by your behavior, and wish to respectfully inform you that I do not appreciate it.

 

Regards,

Northstar

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3 hours ago, Northstar1989 said:

The burden of proof is on the person making the claim.  I didn't claim anything based on a specific price for Iridium, but rather on the previously-cited overall value of certain Near Earth Objects, it was *you* who claimed Iridium (which is not the only metal you'd get when trying to cut out Iridium rich rocks from an asteroid- Iridium is frequently found near Platinum, for instance) sells at $20,000/kg and thus needed to cite your source.

As the one who provided that initial link with the asteroid values, you clearly didn't look up the actual meteors in the listing. The ones with the trillion+ dollar value tag attached are MASSIVE, and largely nickel-iron. The cost estimate must be from the fact that they are representative of an absolutely massive amount of common materials. You then need to worry about the dV needed to get that back to earth (as most of those meteors also list dV requirements in the tens of thousands of m/s)

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5 hours ago, DerekL1963 said:

o.0  You seriously can't google "spot price of Iridium"?  Let me google that for you

 

o.0 Did you read the part where my thought experiment was for ore with 50,000 times the concentration known to exist in space?
 


Which means you need a heat shield.  And protection for the drogues.  And RCS for establishing initial orientation.  And some form of de-orbit system.  And... all the other stuff you simply handwave away.
 


Respectfully, it's strongly supported and well deserved criticism - basic mistakes like the one with ore concentration cited just above amply demonstrate why.

I just want to say that, I appreciate your taking the "Devil's Advocate" stance. I personally don't want to engage in arm-waving or daydreaming but to learn about (a) what is actually known; (b) how well is it known; (c) given those things what realistic might/could/should happen. To me, it is all just an interesting puzzle (though granted if we figure out where the next stock market bubble is going to pop I WILL be taking advantage of that "knowledge!" :D)

That said, I hope you and Northstar can exchange arguments in a casual way and learn from one another just as much as any of us might learn from any one else on this site . . .

Now lets take a look about what seems to be common knowledge of "iridium" . . .

Iridium is one of the nine least abundant stable elements in Earth's crust, having an average mass fraction of 0.001 ppm in crustal rock; gold is 40 times more abundant, platinum is 10 times more abundant, and silver and mercury are 80 times more abundant.[5] Tellurium is about as abundant as iridium.[5] In contrast to its low abundance in crustal rock, iridium is relatively common in meteorites, with concentrations of 0.5 ppm or more.[42] 

What that tells me is, "considering _ALL_ the crustal rock on Earth, iridium is 0.001 ppm." That doesn't tell me much of anything about its concentrations in ore deposits though, and you'll note, since ancient times, humans have been pretty good at deciding where and where not to dig a mine. That is more-or-less the whole point of _prospecting!_ You don't just go out in your back yard and start digging and then use the gross total Earth composition of any given mineral as your basis for determining your profit margins! :D

Not being a mining engineer, I have no idea what a "cost-effective" concentration of any given mineral is. I'm not even sure what sorts of search terms I'd deploy to try to learn actually! :P

The key point here though, and one which you are making Derek, is that the profitability of it really depends on the cost to get the stuff back to Earth, which decomposes into a lot of other factors, with cost to orbit, cost to target, cost to retrieve/refine (whatever), cost to reenter, cost to recover ON Earth, etc. The relative abundance of the mineral in the thing in question is a critical point, and I somehow doubt that anyone has a really good idea at this point.

We got meteorites, whose point of origin can apparently be deduced back to a particular asteroid in at least some cases and we got remote sensing. Until we get some Rosetta/Philae type robots out there close to the some of the buggers, I reckon all we really have are "guesstimates"  . . . given how surprising some of these small objects seem to have turned out to be based on the contrast between what has been learned by close fly-bys/impacts and what was previously "inferred" via telescope . . .

Anyway, as to the meteorites: Williamette Meteorite, which has a captioned photograph in that wiki page on iridium you linked to Derek, has 

Quote

For example,Iridium, one of the least abundant elements in Earth's crust, is found in the Willamette Meteorite at a concentration of 4.7 ppm, thousands of times more than its crustal abundance

Is that representative of a typical asteroid? Or is it anomamlously high? Or are there _some asteroids_ (and/or 'veins' of some) which are even higher in concentration than that? Assuming there were a 1 billion ton chunk of rock floating around out there, and it was made up of 5 ppm, what would it take for that to be cost-effective?

Is that website that @Stargate525 linked to just silly? I have to say, I was amazed when you blithely posted that link! :sticktongue: How the hell did you find out about that!? What do you know about it?

I found it amazing that someone _supposedly_ has that detailed of a database (and with neato graphical presentation) already, but I've just been too busy to revisit it and try to learn more about the site and who runs it.

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27 minutes ago, Diche Bach said:

Is that representative of a typical asteroid? Or is it anomamlously high? Or are there _some asteroids_ (and/or 'veins' of some) which are even higher in concentration than that? Assuming there were a 1 billion ton chunk of rock floating around out there, and it was made up of 5 ppm, what would it take for that to be cost-effective?

Is that website that @Stargate525 linked to just silly? I have to say, I was amazed when you blithely posted that link! :sticktongue: How the hell did you find out about that!? What do you know about it?

I found it amazing that someone _supposedly_ has that detailed of a database (and with neato graphical presentation) already, but I've just been too busy to revisit it and try to learn more about the site and who runs it.

It's extrapolated from public JPL and asteroid tracking data, and cross-inferred from known spectromety of asteroids onto other ones of similar brightness and characteristics. I presume the valuations are based on some fixed point of metals and materials indexes.

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1 hour ago, Stargate525 said:

As the one who provided that initial link with the asteroid values, you clearly didn't look up the actual meteors in the listing. The ones with the trillion+ dollar value tag attached are MASSIVE, and largely nickel-iron. The cost estimate must be from the fact that they are representative of an absolutely massive amount of common materials. You then need to worry about the dV needed to get that back to earth (as most of those meteors also list dV requirements in the tens of thousands of m/s)

Delta-V requirements in the tens of thousands?  That clearly can't be accurate for any Near Earth Object- it takes less than that to get to Mars or Venus.  And you as a KSP player ought to know that Delta-V requirements have nothing to do with the mass of the object (you just get less Delta-V for the same fuel, not a higher requirement).

 

Regards,

Northstar

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58 minutes ago, Northstar1989 said:

Delta-V requirements in the tens of thousands?  That clearly can't be accurate for any Near Earth Object- it takes less than that to get to Mars or Venus.  And you as a KSP player ought to know that Delta-V requirements have nothing to do with the mass of the object (you just get less Delta-V for the same fuel, not a higher requirement).

 

Regards,

Northstar

There's several on the list in the 11-12k dV range. These aren't NEOs, they're in the main belt, and at a good 20-30% tilt to Earth. I'm also not privy to the calculations they're making for the change; somehow I doubt they're fast-forwarding 40 years to get the ideal rendezvous where a plane change won't be needed. I also don't know if they're including the 9k dV to get to orbit.

And according to this dv map of the solar system, Venus takes almost 16k

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2 hours ago, Stargate525 said:

And according to this dv map of the solar system, Venus takes almost 16k

According to that map, it's about 6.8 km/s from LEO to Low Venus Orbit. Add the DeltaV from Earth's surface to LEO, then it'd be about 16k. Even that doesn't assume you're using aerocapture at Venus.

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9 hours ago, Stargate525 said:

And according to this dv map of the solar system, Venus takes almost 16k

Not from LEO as a starting point it doesn't.  It's exactly 6.46 km/s (not including the Delta-V to LEO, which you shouldn't be counting here).  Your statement is either wildly inaccurate, or including a Delta-V gap (cost to reach LEO) which you absolutely should NOT be accounting fior in a discussion of how much Delta-V it takes to reach certain asteroids *from LEO* (which has been the clear context of my discussion- you have no right to deceptively reframe it to make the numbers look bigger).

9 hours ago, Stargate525 said:

There's several on the list in the 11-12k dV range. These aren't NEOs, they're in the main belt, and at a good 20-30% tilt to Earth. I'm also not privy to the calculations they're making for the change; somehow I doubt they're fast-forwarding 40 years to get the ideal rendezvous where a plane change won't be needed. I also don't know if they're including the 9k dV to get to orbit.

They're almost certainly including the Delta-V to get to orbit.

Also, plane-changes are deceptive- because it's perfectly possible to use other planets and moons to provide a large component of a plane-change Delta-V with enough time and gravity-assists.  For that matter, if you're clever about using gravity-assists off of Mars to raise your apoapsis relative to the Sun, and perform your plane-change when the Ascending or Descending Node is near Apoapsis, you can get out to those asteroids for a lot less Delta-V than that.  Coming back, gravity-brakes and aerobraking help (actually, aerobraking *at* Mars helps when getting to the asteroid belt too, since this raises your periapsis relative to the Sun...  And if your target inclination is far enough from the orbital plane, you're actually better off aerocapturing and gravity-braking off its moons into orbit at Jupiter first instead, and then using its complex moon-system to gravity-assist into a closer trajectory to your target orbit on the way back out...)

All this would probably take many, many years though, which makes those asteroids very poor candidates for mining.  But your even bringing them up is a disteaction and a straw-man, there is literally no reason to go to any of those asteroids when there are hundreds of smaller asteroids in easier-to-reach orbits...

 

Regards,

Northstar

Edited by Northstar1989
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3 hours ago, Northstar1989 said:

Not from LEO as a starting point it doesn't.  It's exactly 6.46 km/s (not including the Delta-V to LEO, which you shouldn't be counting here).  Your statement is either wildly inaccurate, or including a Delta-V gap (cost to reach LEO) which you absolutely should NOT be accounting fior in a discussion of how much Delta-V it takes to reach certain asteroids *from LEO* (which has been the clear context of my discussion- you have no right to deceptively reframe it to make the numbers look bigger).

They're almost certainly including the Delta-V to get to orbit.

Also, plane-changes are deceptive- because it's perfectly possible to use other planets and moons to provide a large component of a plane-change Delta-V with enough time and gravity-assists.  For that matter, if you're clever about using gravity-assists off of Mars to raise your apoapsis relative to the Sun, and perform your plane-change when the Ascending or Descending Node is near Apoapsis, you can get out to those asteroids for a lot less Delta-V than that.  Coming back, gravity-brakes and aerobraking help (actually, aerobraking *at* Mars helps when getting to the asteroid belt too, since this raises your periapsis relative to the Sun...  And if your target inclination is far enough from the orbital plane, you're actually better off aerocapturing and gravity-braking off its moons into orbit at Jupiter first instead, and then using its complex moon-system to gravity-assist into a closer trajectory to your target orbit on the way back out...)

All this would probably take many, many years though, which makes those asteroids very poor candidates for mining.  But your even bringing them up is a disteaction and a straw-man, there is literally no reason to go to any of those asteroids when there are hundreds of smaller asteroids in easier-to-reach orbits...

I can't be bothered to keep the 'clear context' of your discussion in mind throughout this entire thread. I have a right to make my arguments however I want, and including the dV to LEO when that is exactly what you're going to need for the first miner (Unless there's an orbital shipyard I'm unaware of) is not deceptive at all.

"It will cost a lot to get there" Is not a distraction any more than "But the gas will be atrocious" is a distraction off of the argument of where one should drive. A straw man would also imply that I'm setting up a false argument YOU made. Since I'M the one who brought the fuel aspect up as a negative to the trillion+ dollar asteroids, it can't possibly be one.

Further, YOU are the one who didn't bother looking at your sources, and assumed that the asteroid listing was all NEOs. YOU are the one who made the assumption here, and I don't appreciate being called out as deceptive and distracting when I am merely pointing out the flaw in your own argument.

Good day.

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Well this rather tense hearing clarified to me a lot of things about how and why "space flight" has got more expensive. Reflects a lot of the preceding comments by forumites who have more expertise in rocket science/industry than me: if you want your sats to have extreme reliability and flexibility on demand, you pay for it . . .

 

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  • 11 months later...
2 hours ago, Diche Bach said:

What about lithium? Is it possible that there are chunks of lithium frozen out there in the Oort Cloud, and would it possibly be valuable?

If you can get your mining rig to Oort Cloud in any reasonable timeframe, then you've most likely evolved way past lithium shortage.

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2 minutes ago, Scotius said:

If you can get your mining rig to Oort Cloud in any reasonable timeframe, then you've most likely evolved way past lithium shortage.

Hah! Good point :)

What about nuclear pulse propulsion? That allows at least 0.2 if not 0.4 c (on paper) without any substantial "purely theoretical technology."

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On paper it looks awesome. But in my country we have a saying: "Paper will take anything." We also tried pulse jet engines in the past - because they seemed to be simpler and cheaper than regular ones, while offering good performance. Guess what - it didn't pan out. Only broader application for them were V-1 flying bombs. And that's about it. Why? Imagine welding an anvil to the back of your car, and propelling it forward by repeatedly hitting it with a wrecking ball. Your car wouldn't like it. Planes (which have to be light to fly well) didn't like it. A rocket (and her crew) wouldn't like being hit repeatedly by a nuclear explosion either.

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