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You want a super expensive Shuttle to ferry bulk minerals out of the sky? Natures been doing it since the beginning of time. Just strap one of those cheap inflatable heat shields and a parachute on it and your good to go.
No we want a super expensive to design but cheap to operate Shuttle so that we can send up the crews and infrastructure components so that we can send bulk minerals back to Earth. Inflatable heat shields still have to be sent up and that is where you get your true RLV Shuttle.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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If we ever intend to mine anything in bulk in space, we would need launch costs well beyond ten times as cheap, and a super-RLV flying often or a space elevator are the only ways it will ever happen short of Star Trek transporters or anti-gravity drive.
And why in the heck would you strap heat shields and parachutes to metals drops? If we have RLVs and tugs they will be coming back to Earth at the end of each trip where the minerals could be returned. Much better then dropping expensive Kinetic Energy Missiles from inaccurate interplanetary distances and hope theives don't steal your shipment of Platinum bars or your canister of toxic Osmium burning up and dispursing its contents.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I know this isn't original, but maybe someone can tell me why we couldn't deliver metals to Earth's surface by making big, low density "bubbles" by carefully inflating molten metal in LEO? If it's light enough, it seems like it shouldn't melt or burn up, and stay intact enough to float when it splashes down in the Pacific.
Platinum, being hard to melt, might have to be delivered in small quantities inside a bubble of other metal.
Turn the ISS into a bubble factory - get some use out of it.
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-Melting metal exposed to vacuum would cool and harden too quickly to "blow bubbles"
-Couldn't control decent very well, especially with a sphere of low density
-Could get hot enough to deform signifigantly and thus not be aerodynamically shaped consistantly, controlled decent impossible
-They still might burn up; if they don't weigh enough, they can't absorb the heat of reentry, and will burn anyway. Almost everything burns when it gets hot enough.
-People might steal your bubbles
-Still couldn't drop toxic PGMs safely
-How do you track them after they impact the ocean?
...But most of all, WHY? We aren't going to be bringing thousands or even hundreds of tonnes of the stuff back down, most shipments will probobly be in the kilogram range infact. There is no good reason not to simply bring them back down when you send a cargo RLV up.
I want to jump up and down on the neck and kick in the temple any more of this asinine reoccuring farce of an idea of using the ISS for anything, and I mean anything, other then a Russian space hotel or anti-satelite weapon target practice. (no offense to you, TwinBeam) Its in the wrong orbit to efficiently launch to, it could never be expanded because the structure couldn't handle the torque, and the thing will be completly broken down and utterly uninhabitable by the time we start serious Lunar mining.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I know this isn't original, but maybe someone can tell me why we couldn't deliver metals to Earth's surface by making big, low density "bubbles" by carefully inflating molten metal in LEO? If it's light enough, it seems like it shouldn't melt or burn up, and stay intact enough to float when it splashes down in the Pacific.
Platinum, being hard to melt, might have to be delivered in small quantities inside a bubble of other metal.
Turn the ISS into a bubble factory - get some use out of it.
There are several problem with that Idea. First the problem of putting it into a bubble. Even being in a bubble, you would have to send it into degrading orbit that would take one to two weeks to get it down, you would have no control where it come down at. If the angle too sharp it will burn up on a firery return. Even then it would still be questionable you could do it. There is a guy that intends to get into space using balloons and get back down using balloons using an ion drive engine for a gradual excelleration over one week period each way. Whether that can be done is also in question.
From what we know right now, probably not.
Larry,
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First the problem of putting it into a bubble. Even being in a bubble, you would have to send it into degrading orbit that would take one to two weeks to get it down, you would have no control where it come down at. If the angle too sharp it will burn up on a firery return.
Making the bubble may require developing some technological expertise, but I don't see it as a major roadblock - melt a blob of metal, inject low pressure air, let it solidify. To put platinum in it, cut a small hole, insert, patch neatly.
As to controlled re-entry, I expect one would put on a very small rocket, and when it is entering it's last few orbits, give it a shove at just the right time to insure it comes down in the middle of the ocean.
If you get its average density low enough, I don't think burning up should be an issue.
One issue would be that it might collapse in air pressure - but if you pressurized it before dropping it, it might burst when it gets hot during descent. A pressure relief valve that gives way to anything over about half an atmosphere difference between inside and outside should do the trick.
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You can drop several tons of material at a time with a disposable heat shield and parachute, both of which can be launched and stored by the dozen cheaply.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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What is it with "dropping tonnes of material?" NO and again no
There isn't going to be any "drop tonnes of material" because there is nothing - nothing - we need in vast many tonne quantities from space. We have all the bulk material we will ever need for anything right here on Earth; what we DO need is the rare stuff that isn't "natural" like PGMs, which basically all our sources are from meteor impacts. Again, of these we only need shipments in KILOGRAM quantities. Not tonnes.
If we are ever going to have serious, really signifigant mining on the Moon, we are going to need a reuseable launch vehicle and (perhaps doubling as) a reuseable transit vehicle from Earth orbit to the Moon and back. It will just be too expensive to throw away launch and transit vehicles for mining, even if they are ten times as cheap as todays.
In this case, since the vehicle(s) is going BACK to Earth, for crying sake, just put the ingots on the dang ship. There isn't any other sane way of doing it. No bubbles, no disposable heat shields, no parachutes, just put the ingots in the RLV and send them back down.
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Bubbles:
-Again, the metal will cool very fast in space, and will be a solid so you can't "blow" anything
-Small expendable rockets are expensive, so are the attitude control systems, power systems, navigational beacon and hardware, and so on. I thought the whole point of the bubbles is minimum possible cost for reentry?
-If the density is too low, the thing will heat up very rapidly, and won't pass through the atmosphere before getting so hot it will burn up. All-metal heat shields have to be big, thick, and heavy (see Mercury, Soyuz, and early ICBMs).
-A pressure reliefe valve on a sphere won't have any means of orienting itself, and so would probobly not face away from the heat of reentry, and melt right off.
If these bubbles are really that light, then you are going to absolutely lose them in droves when they inevitibly burn up. If you are moving such small amounts of metal this way, why bother, go with another route that uses higher densities... like ingots on RLVs for instance.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Bubbles:
-Again, the metal will cool very fast in space, and will be a solid so you can't "blow" anything
-Small expendable rockets are expensive, so are the attitude control systems, power systems, navigational beacon and hardware, and so on. I thought the whole point of the bubbles is minimum possible cost for reentry?
-If the density is too low, the thing will heat up very rapidly, and won't pass through the atmosphere before getting so hot it will burn up. All-metal heat shields have to be big, thick, and heavy (see Mercury, Soyuz, and early ICBMs).
-A pressure reliefe valve on a sphere won't have any means of orienting itself, and so would probobly not face away from the heat of reentry, and melt right off.
If these bubbles are really that light, then you are going to absolutely lose them in droves when they inevitibly burn up. If you are moving such small amounts of metal this way, why bother, go with another route that uses higher densities... like ingots on RLVs for instance.
I'd disagree about not needing tons of platinum - on a global scale we will be wanting tons of it. We're producing 133 tons a year on Earth. If the moon is to be a significant source worth investing billions to exploit, I think we're talking maybe 100 tons a year - a couple billion dollars worth. Even if a RLV could handle a ton of it, that's 100 flights a year - eating up any profits.
And I don't think you can project from metal heat shields for dense re-entry vehicles to the bubble concept - a bubble will have much less kinetic energy to convert to heat, and will shed most of that energy high in the atmosphere, after which it will fall at terminal velocities too low for significant heating. Taking an extreme example, would you expect an inflated toy balloon to burn up on re-entry? A bubble will need to be more like that balloon, than a typical re-entry vehicle.
I won't pretend to have worked out the technology needed to make metal bubbles - but if the metal cools faster than is desired, keep heating it until it's inflated as much as you want. Otherwise, fast cooling is a major benefit for reliable bubble production.
By using a few crude lunar fabricated parts, I'd guess each bubble might get by with as little as 2kg of Earth-launched components, and return maybe 10kg of platinum. Even if it's 10kg of Earth components, each bubble might cost $50k to launch parts. No need for expensive attitude control, btw - the mass of the rocket and the platinum, fixed to one side of the bubble, will keep the rocket oriented forward.
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"Even if a RLV could handle a ton of it, that's 100 flights a year - eating up any profits."
Mining a hundred tonnes of PGMs anually would require mining tens of thousands of tonnes of ore at least, and processing it to make the metal. Such an operation would require a hundred RLV flights a year easily, and if one of them brings back a few tonnes of ingots, then whats the problem?
I disagree that we will need so many tonnes anyway, because the stuff will still be expensive to mine, it will supress demand somewhat.
You still haven't solved a good way to capture the bubbles either, they will just fall all over the place. I don't think you can make the rocket light enough either without going through too much trouble to precisely position them for Earth reentry. You would need to drop them from LEO, and to get them there you would need a reuseable Lunar transit vehicle. So if you are going half way to Earth by a reuseable vehicle anyway, just go the other half of the way back to the surface.
You plan is unworkable, inefficient, and unnessesarry
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Mining a hundred tonnes of PGMs anually would require mining tens of thousands of tonnes of ore at least, and processing it to make the metal. Such an operation would require a hundred RLV flights a year easily, and if one of them brings back a few tonnes of ingots, then whats the problem?
I disagree that we will need so many tonnes anyway, because the stuff will still be expensive to mine, it will supress demand somewhat.
At about $1000/troy-oz, a ton of platinum is worth only $24M. How do you expect to make that profitable with a ton or probably much less returned per RLV launch? Talk about "unworkable" and "inefficient"...
IF mining of platinum and return to Earth is to be made practical, it will likely need at least a $1billion a year gross income - about 50 tons, minimum - to hit barely adequate economies of scale. Yes, it would take a lot of mining and processing to get that much platinum, and no, I'm not yet convinced it's practical. I'm trying to see if there's a way to get one small component of cost down to a practical level. Other components may prove to be deal killers.
You still haven't solved a good way to capture the bubbles either, they will just fall all over the place. I don't think you can make the rocket light enough either without going through too much trouble to precisely position them for Earth reentry. You would need to drop them from LEO, and to get them there you would need a reuseable Lunar transit vehicle. So if you are going half way to Earth by a reuseable vehicle anyway, just go the other half of the way back to the surface.
One solution might be to let them fall "all over the place" - that'd likely be cheaper than putting a rocket on them, even if you only recovered half of them - except of course that people would object that with maybe thousands of them falling a year, they'll end up killing a few people. (Some semi-accurate de-orbiting alternative to a rocket would be great, if anyone out there is creative enough to come up with something that doesn't need many components shipped up from Earth.)
But sticking for the moment with the idea of them splashing down in the Pacific - they can probably be limited to a 100 mile wide by 1000 mile long path. A ship can patrol back and forth across that, picking up the bubbles by homing in on their transponders. It might cover that path over about a week, picking up perhaps 200 bubbles a week, each containing perhaps 20 pounds of platinum - about 2 tons a week. (Those are guesses for purposes of illustration, by the way - not a design.) There are some security issues, but nothing insoluble.
A re-usable vehicle from the moon to LEO has much easier requirements than one that has to be launched from Earth, and later return into Earth's atmosphere and land safely. It should cost far less to develop. It can be automated - no crew needed. One could make an automated Earth re-entry RLV too - but I don't think that's what you're talking about when you say "RLV", and it'd likely cost about a million times as much as one bubble, and perhaps 100x as much as a moon to LEO vehicle.
The fundamental issue is whether it'll be possible to make space activities cheaper by building enough productive infrastructure in space, to avoid shipping a lot of mass up from Earth. My guess is that someday someone - maybe China, or maybe the US in reaction to fears of China doing it - will invest several hundred billion into building that infrastructure, without any real hope of that being repaid in any reasonable investment timeframe.
You plan is unworkable, inefficient, and unnessesarry [sic]
Hmm - well, that's open minded of you, considering you are assuming an un-specified RLV system, that would be far less efficient even if it works, and as far as I can see isn't needed - let alone a hundred RLV launches a year.
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No, they will probobly never build a true HLLV, but they don't have to in order to contribute to getting man off this rock. If NASA is going back to the Moon to establish a base, then they are going to have to spend in the region of $800M-$1Bn every time they need to exchange crews, $500-600M for every heavy unmanned payload, or around $300-400M to send a Progress-like supply mission. If they have to send these on a regular basis, then this will chew up probobly around 33-50% of NASA's manned spaceflight budget, which will make doing Mars right and well difficult.
Elon's rockets don't have to be cheaper then Russias, which is possible anyway on the account that they are built simpler perhaps, they just have to be cheaper then what NASA is paying now. Why? Simple, so that Russia doesn't have veto power over the US Lunar program if Putin or his sucessor decide they need to excercise some political leverage over us. As I have said many times, Russian rockets are financially cheap, but politically speaking they are ruinously expensive. Elon's rockets don't have this limitation, not to mention the company is American, which will make Congress much happier too.
If SpaceX can offer a launch vehicle in the region of Delta-IV HLV or TheStick for his advertised $50M, how could NASA and the USAF not buy them?
It's too early to judge so we should wait and see and I hope Elon's next Falcons fly a lot better
but Forking out millions for an expensive fireball is not on
http://www.newmars.com/forums/viewtopic.php?t=4535
given a few dollars I'm sure the ancient Chinese could build you some cheaper fireworks
http://www.chebucto.ns.ca/Philosophy/Ta … o-tzu1.gif
'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )
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What is it with "dropping tonnes of material?" NO and again no
There isn't going to be any "drop tonnes of material" because there is nothing - nothing - we need in vast many tonne quantities from space. We have all the bulk material we will ever need for anything right here on Earth; what we DO need is the rare stuff that isn't "natural" like PGMs, which basically all our sources are from meteor impacts. Again, of these we only need shipments in KILOGRAM quantities. Not tonnes.
If we are ever going to have serious, really signifigant mining on the Moon, we are going to need a reuseable launch vehicle and (perhaps doubling as) a reuseable transit vehicle from Earth orbit to the Moon and back. It will just be too expensive to throw away launch and transit vehicles for mining, even if they are ten times as cheap as todays.
In this case, since the vehicle(s) is going BACK to Earth, for crying sake, just put the ingots on the dang ship. There isn't any other sane way of doing it. No bubbles, no disposable heat shields, no parachutes, just put the ingots in the RLV and send them back down.
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And how many fuel cells do you intend to create with that ingot of platinum? Surely not the hundreds of millions needed in the US alone to switch to a hydrogen economy? Which is the only thing that would ever justify mining beyond experimental levels.
RLVs will never be used for anything beyond personel transport and extremely fragile equipment.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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Platinum's properties, what really makes it indespensable, only occurs on the surface of the metal, just the top few layers of atoms, and the rest under it is completly inert.
Thus, catalysts don't need very much platinum at all, since a very small amount of platinum properly applied as a thin coating can yeild a huge area. Hence, a carefully designed fuel cell can get away with a tiny amount of platinum. Small cells would probobly only need milligrams, and largish car-sized ones only a few grams. A one-tonne shipment of the metal would thus produce hundreds of thousands of fuel cells.
We need platinum and related metals for other things too, PGMs are the cornerstone of many industrial processes, for which there aren't any good alternatives. Also, chances are the computer you are writing this on has trace amounts of platinum in its electronics. There are other uses besides fuel cells.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Upon a little more thought...
I think its possible to turn a profit with limited Lunar PGM mining using only next-generation expendable rockets. However, anything beyond eeking out small amounts of the stuff, a medium-lift RLV is non-negotiable.
Such a vehicle is possible, we could make one today with Proton or Atlas-V level payload, since the crew cabin, escape systems, and the structure to support a good sized crew weigh nearly as much as a good sized payload. If you delete them, then there is your payload right there. The key is just to never, never make the vehicle carry people and payload, which is one of the lessons from Shuttle.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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