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Tuvas


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Hey all
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Hey all, don't know if any of you will remember me, but I used to be a regular on these boards a few years back. I left the country for a couple of years, and almost forgot about these boards, but I was cruising the net the other day, and decided that it was time for my return.


The previous time that I was here, I was a space activist, but had no real knowledge of operations. Still, that was enough to allow me to write a paper, entitiled "Electromagnetic Pulse as a result of Nuclear Pulse Propulsion", which took a relatively simple approach to seeing what kind of an affect EMP would have on a project Orion spacecraft.


Since then, I started working with the student satellite program at my university (University of Arizona). Recently, an oportunity to work with the control team of the HiRISE camera was posted, and I applied and was accepted. HiRISE, for those who don't know, is the most powerful camera on the MRO, which achieved martian orbit only a few days ago.


I hope to get to know all of you!



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Tuvas
HiRISE Operations Control team member
University of Arizona Student
See my blog http://tuvas21.blogspot.com/
See my paper on Project Orion http://www.u.arizona.edu/~tuvas/
GoogleNaut


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Congrats on your participation in flying hardware--there is great satsifaction in knowing that one has personally worked on hardware that is actually on site, collecting data and contributing to human knowledge. I can only imagine that that is a wonderful feeling!

Welcome back to the board!

I am currently looking at a 'design' study for infrastructure for mining asteroids. Nearer term returns could be platinum group metals, followed later by more bulk metal/volatile returns. I am looking at what it would take to start small and bootstrap it into a major space industrial operation--returning platinum group metals will be a critical primary payback for initial investment and technology demonstration.

A nuclear powered, VASIMR propelled spacecraft able to process multiple propellant streams (a critically important feature of the VASIMR) will be necessary to achieve it. Mineral extraction and primary materials processing will also probably have to occur on site. Defining a mission of such complexity is a staggering task--I learn more about it every day! The goal of all this is a research paper, an article or maybe even a book. I'm not sure how far I can go with it--but I'll take it as far as I can.

And that's what this site is all about!

Ty Moore
"GoogleNaut"


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Tuvas


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VASMIR was always my favorite of the nuclear rockets, it seems to be the one that combines the best features of high-powered, but low-risk. Too bad project prometheus isn't going anywhere... Oh well.


As for your idea of mining astroids, what I would suggest is to do the following. First of all, transport a satellite with lots of gold, iron, silicon if avaliable, copper, etc. Secondly, build a space factory. Then build satellites already in orbit, which would probably be cheaper than if they were built on the ground, they would be better, and best of all, they would already be in space. From there, you could make alot of cash, with which you could proceed to return some of the precious metals to the earth, but only the most precious.



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Tuvas
HiRISE Operations Control team member
University of Arizona Student
See my blog http://tuvas21.blogspot.com/
See my paper on Project Orion http://www.u.arizona.edu/~tuvas/
GoogleNaut


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That's pretty much the idea--it sounds like I might be on the right track.

First payloads would be precious metals---a 1000 metric ton cargo of platinum (80%) and rhodium (20%) will have a potential earth market value of $40 billion. 5000 metric tons of volatiles in LEO will have an on orbital value (cost of boosting them there from earth's surface) of $100 billion (of course this will be discounted--thus making space more affordable!)

Satellite and orbital platform construction, on orbit, will reduce/eliminate costs of launch. Also, using a resuable Solar VASIMR or SEP upper stage for positioning and retrieval of satellites should allow regular servicing of faulty equpiment. This will only increase the value of the assets already there. Also, deorbiting space junk or retrieving and recycling will increase the value and safety of near earth space.

An inherent design philosophy of maximizing payload for every Ground Launch makes sense---delivering mostly empty tanks to an orbital supply depot, and extracting all remaining propellant residuals makes sense, because the current cost of boosting payload is about $10,000 per pound. So anything delivered to orbit will be worth atleast that much...




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Tuvas


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There are a few problems with just taking platinum.


1. How are you going to filter it out?


2. That large of a chunck of platinum would seriously decrease the market value for it.


The chunck of rock in LEO would be easier, and wouldn't reduce the demand, especially since it would be hard to get the factory process started. Also, alot of the development of satellites goes into helping them launch successfully, so...


My idea is this. There is an astroid that has a chance of hitting the earth in 2036 called Apophis. It will be very close to the earth about 7 years earlier. Why not use this astroid, and just try to nudge it into orbit, I'm sure some really good simulations could figure out how to do it. What do you think?



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Tuvas
HiRISE Operations Control team member
University of Arizona Student
See my blog http://tuvas21.blogspot.com/
See my paper on Project Orion http://www.u.arizona.edu/~tuvas/
GoogleNaut


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You have some good points.

1) Platinum can be 'filtered' out by processing the metals of the asteroid using the Mond process. Metal is pulverized to a powder, heated and then sujected to pressurized carbon monoxide. This makes a mixture of gasses, called carbonyls: iron pentacarbonyl Fe(CO)5 and nickel tetracarbonyl Ni(CO)4 which can be easily volatilized and then condensed at two different temperatures. Reheating the seperated condensates will drive off the carbon monozide for reuse, leaving very nearly pure metal powders.

Here's the kicker: the stuff that was left after initial treatment with carbon monoxide is a mixture of metals, mostly platinum group metals, gold, and other trace materials. Acid leaching followed by electrorefining should seperate these metals into very nearly pure form.

2) Dumping a thousand tons of platinum on the market, all at once won't do much good. However, by ramping up its introduction gives time for new uses to come on line, and will slowly depress the price--naturally--but will do so without serious disruptive consequences. This necessitates stockpiling the metal in a secure location--a protected vault, perhaps onboard a Low Earth Orbit space station.

Apophis masses around 4.5*10^10 kg (or about 45 million metric tons.) To capture this rock into a highly eccentric earth orbit, possibly by doing a lunar gravity assist, will still require a delta-v change of atleast 1000 meters per second. Assuming an efficient VASIMR engine of 30,000 seconds of specific impulse, this will require about:
153,000 tons of liquid hydrogen. To process this much propellant would require a rather larger engine (also to generate enough thrust bend the trajectory.) I'm thinking that a 200 MWe VASIMR powered by a 500 MWt nuclear reactor with a really big hydrogen tank could do it. I'm not sure what Apophis' composition is, so the necessary volatiles may not be present in quantity. This would almost certainly necessitate going to a near earth orbit crossing comet nucleus to mine the volatiles anyway...


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10kBq Jaro


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This would be considerably easier with a comet-type object: just feed water/ammonia/methane solution to a big NTR. The comet is its own propellant tank, one might say....


I would also suggest going for something much smaller than Apophis, less than a 100 m long -- a fragment of a comet ??



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Philipum


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Another possible but much more risky way to put the asteroid into Earth orbit would be to give it a little push which is so well calculated that the asteroid will come into orbit by itself during a subsequent passage. I hope we will never try it!

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Tuvas


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I don't know orbital physics very well, but I have always understood that it is highly complex. Still, I think the whole thing could be done, if someone was willing to try, and why not try the first one to be one that is close to the earth. If we could take a potentially dangerous rock, and mine it, wouldn't that be the best thing overall?

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Tuvas
HiRISE Operations Control team member
University of Arizona Student
See my blog http://tuvas21.blogspot.com/
See my paper on Project Orion http://www.u.arizona.edu/~tuvas/
GoogleNaut


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Well, asteroid deflection is definately important. The main factor is time. The bigger the rock, the more time that is needed to incur deflection.

In my humble opinion, establishing a space based mining infrastructure, which would include ground-to-orbit transportation, Low Earth Orbit Depot and Staging Area; and deep space transportation are all critical technologies needed for industrialization. By products of this effort will include: expanded deep space detection and tracking of potentially dangerous target bodies; expanded use of unmanned deep space probes to actually go out and characterize these bodies, not just for mineral resource extraction, but to evaluate the structural geology (geophysics, I guess you could call it) of a potentially threatening body in order to evaluate the means to deflect it. And of course, some kind of deep space vehicle, useful for emplacing mining/refining equipment and retrieving minerals, but also useful as a potential deflection mission if the need should arise.

If we don't build the necessary space infrastructure, the point is moot anyway...

Ty Moore


-- Edited by GoogleNaut at 18:32, 2006-03-16

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john fraz


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questions, ideas, sources for reading
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> There are a few problems with just taking platinum.


Certainly, but I'm influenced by a lot of writings by people who've taken a long time and good hard looks at it. For every part of the process for which we don't know the best way, there are a dozen alternatives which would work well enough to carry it off. This quandary of ignorance of the best way is what's kept anybody from even trying. All that really matters is who gets there first, with anything at all which produces anything. "Perfect" is the enemy, while good enough" would do well enough.


>1. How are you going to filter it out?


We here shouldn't even go too far into describing the various ways. Suffice it to give a decent bibliography, and we're all (hopefully, eventually,) passingly familiar with the basics.


An excellent place to start:


permanent.com    Projects to Employ Resources of the Moon and Asteroids Near Earth in the Near Term


Plenty of good articles, from processes and techniques, to products and services, to a near-term private profitable mission.


As well, there are any number of reports and articles in professionally peer-reviewed journals, from Geology or mining to the AIAA and SSI which talk about the many & varied suggested processes.


>. That large of a chunck of platinum would seriously decrease the market value for it.


So? it'd still pay off the mission investment and give whoever flew the mission an immense technical lead in a huge, immensely profitable, completely open arena. In his book "Mining the Sky" John S. Lewis reported on a survey of asteroidal resources by J.Kargel of the USGS: the platinum group and precious metals alone from a 1km stony asteroid, if brought back to Earth markets would be worth ~$5trillion, though flooding the markets with so much at once would drop the value to only ~$300 billion.(wah...)


>... There is an astroid that has a chance of hitting the earth in 2036 called Apophis. It will be very close to the earth about 7 years earlier. Why not use this astroid, and just try to nudge it into orbit, I'm sure some really good simulations could figure out how to do it.


That's close to how it'd work. "Closeness" or simple physical proximity (at any point in time) don't matter so much. What matters is Delta-V needed to reach it, or complete total velocity change. This determines (for instance) how much of a mass placed in LEO could be payload for the destination, and how much is fuel to be burned off getting there. One that's going to come by really close could be hard to reach if the relative velocity change is large. Others that might not come as close any time soon might need a tiny fraction of the total Delta-V to get to it with a meaningful payload.


Any of many of what are variously termed "Earth-Crossers" might do very well; Many of these (perhaps most if not all) are easier to get to than our Moon (though travel times are longer), and have far FAR better resources once you get there. Many which spend most of their time very close to 1 AU (Earth orbit from the Sun), taking very closely 1 year, are obvious good picks, since they obviously have orbits that don't require much velocity change to get to. This means that a given booster (or several shots assembled in LEO, more likely) could place more payload there, and something like a solar thermal rocket using asteroidal ices as reaction mass could very well propel it home. Most likely, it'd take close to a decade to bring it back, and we'd have to send relief crews out with more tools and supplies. It'd do a couple of Earth swing-by and maybe a swing by of Venus, all the while gradually warping its trajectory so there's less and less relative velocity each time. The last Earth pass might send it out around the Moon, which drags the last velocity out if it so it's captured around Earth finally. There have been many very similar scenarios described for asteroids in a given class (First they are classified according to their orbital characteristics, then it's a matter of finding one of whatever type you want or varying your processing techniques to match the type).


another good site:


NEOfuel.com: Near Earth Object fuel (rockets that take energy from one source, to energize propellants from another)



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"A devotee of Truth may not do anything in deference to convention. He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it." Monhandas K. Gandhi
GoogleNaut


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Asteroid PGM's
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This is essentially the idea--the thought of returning platinum group metals just expedites the payback. Quicker payback increases its attractiveness to investors, and simultaneously decreases the risks from a financial point of view.

Price depression of the market for PGM's is not necessarily a bad thing. Cheap platinum can open--wide!!!!--whole new markets in catalysts alone. Cheap PGM catalysts can do far, far more for the environment and energy policies by creating a 'bridge' that allows energy to flow from prime movers like nuclear plants, hydroelectric, and solar power satellites to the transportation sector--where a lot of energy is needed--by creating more energy efficient pathways to the Ficsher-Tropsch Synthesis reaction to create synthetic hydrocarbons from carbon monoxide and water vapor, and also by creating a vast new market for relatively inexpensive and more practical fuel cell vehicles. Cheap PGM's in conjunction with inexensive power allow us to create a sustainable transportation infrastructure by using 'mined carbon' (in the form of coal, tar sands, shale oil, etc.) and supplimenting it with 'recycled' carbon (in the form of biomass or biogenic carbon.) With cheap PGM's and cheap energy, it becomes possible to almost completely 'close the loop' on the carbon cycle.

As space industrialization matures, it becomes possible to return other valuable materials to Earth: gold, copper, titanium, semiconductors (both finished and unfinished,) nickel, cobalt, rare-earth metals, etc. The asteroids are likely to be a veritable treasure trove of all of these elements.

Introducing Asteroid PGM's into the market at a controlled rate will ensure non-disruptive (i.e., catastrophic ) change will occur--giving the market time to establish a new dynamic equillibrium. As the price of PGM's fall (as global inventories rise,) then so will new markets open up for increased demand. Money can still be made in great quantity, but the price per ounce of platinum will fall. Current demand for PGM's is around 150 tons per year. Demand has been steadily increasing, but supplies haven't been able to increase at the same rate. The price of PGM's has steadily risen as a result. Suddenly increasing the current supply by 50% (75-80 tons) will certainly allow the price to fall a little, but it won't go down that much. Steadily increasing that supply over the period of a decade or even 2 decades will allow the price to settle into a new--lower--price. If a single return mission was chosen, that return a whopping 1000 tons to LEO, then a low earth orbit secure depot could meter the PGMs into the market at a controlled rate. I'm not sure what kind of security you'd need for the station (the only space pirates I've heard about were in SciFi But anything could happen for a first time!)

P.E.R.M.A.N.E.N.T. is a neat website. I like their philosophy of near term industrialization. It makes me think that it should be possible to create an economic model that takes into account the inherent high launch costs of moving things from the ground into orbit, and take into account mass multiplication that is possible with asteroid mining. It seems to me that even though it may still cost $10-20 thousand (US) to put a kilogram into low earth orbit, that if sufficient quantities of valuable materials were returned (asteroid PGM's) coupled with the value of construction materials brought back to Earth orbit for satellite and spacecraft construction (cost savings per kilogram) and with the net value of contracts to build, operate, and maintain such facilities, then launch costs could end up being subsidized substantially by these other operations. Returning precious metals to earth as ballast for reentry vehicles constructed using asteroid and lunar derived resources which are also returning things like titanium (in massive structure of RV,) carrying a jettisonable payload of microchips or something else (which can parachute to the ground) makes sense. Slag from processing lunar regolith could form much of the mass for an ablative heat shield. A big RV need not have parachutes, it could be made to simply slam into the desert in Nevada, or Utah for recovery. Titanium casks carrying PGM's could be recovered, while the titanium structure was simply cut up and hauled away for recycling. Keep it simple...


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