From: szabo@techbook.com (Nick Szabo)
Subject: Re: Wealth in Space (Was Re: Clinton and Space Funding)
Organization: TECHbooks --- Public Access UNIX --- (503) 220-0636
Date: Sun, 27 Sep 1992 12:17:32 GMT

In article <26SEP199221403772@judy.uh.edu> wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov writes:
>Nick, Nick, Nick, don't you ever read the reports about recently discovered
>near Earth Asteroids?  

I've been reading and posting about them for years. :-)

>There is one of the found in 1987 (I forgot the 
>designator) that is confirmed by albedo and spectral studies to be nickel 
>iron, as are about 10% of all meteorites found on earth.

But this is a poor source of metal, unless there is surface metal
regolith.  It's very tough to chop solid metal into pieces.
We do find metal regolith in many carbanacious meteorites,
and as a bonus the platinum group is enriched (in some 
carbonaceous meteorites) to concentrations much higher than earth ores.  
We have to do significant exploration to find the right asteroids; picking 
random ones doens't work (which is why I get uptight when they target yet
more boring silicate-type asteroids).  Furthermore, we need volatiles
to process the metals into useful products, and for propellant to
bring the stuff back to earth orbit safely.

>...there was approximately 90 billion dollars worth
>of gold and 1 trillion dollars worth of Platinum, give or take a few million.

But there's $10's of trillions on Earth.  What is important is the
concentration, and our ability to send out equipment to process the
stuff, and (especially in the case of low price/# commodities like
nickel and iron) our ability to bring it down to earth safely and
politically correctly, which I doubt for the cheaper stuff.  The 
concentration of platinum is much higher than on earth in certain kinds 
of asteroid regolith; the concentration of gold is much lower than earth 
mines in everything we've looked at so far.  I'm hoping for placer
gold deposits on Mars, but that's speculative at this point; MO may
provide some good clues.

>Currently a new oil field cost
>10 billion to develop (Alaska North Slope for example).  This is no more than
>a mission to develop the asteriod would cost, with a far greater pay off.

Do you have a design overview for this, and cost estimates for the
components, that you could post?  Similar mining equipment on earth
weighs in the thousands of tons; just launching it to LEO would use up
most of your budget.  I have checked out the stuff done at the
various space development cons BTW.  Some of it assumed the promised 
shuttle price of $200/kg to LEO, some even less for a specualitve SSTO.
The real price, which has been similar for decades, is $6,500/kg and
up.  None of the equipment designs are detailed enough to get a good
grip on their difficulty and costs.

Not that I don't think we'll be able to do it in two to four decades, and 
for less investment and more revenue than most other space-mining schemes,
but there's a large amount of automation tech, space-dynamics tech, 
mining-in-vacuum tech, processing tech, etc. that needs to be designed 
and tested.  Most mining & sorting equipment  assumes gravity, atmosphere 
or both.  The NASA projects you keep promoting spend $100's of billions 
while ignoring this stuff.  This is another example where NASA should be 
working on commercially promising stuff, instead of going off in its own 
dead-end direction.   The best space suits and capsules in the 
universe won't let us mine an asteroid if the dust clogs or grinds 
down the machines.  Most likely, a requirement for astronauts in the
early stages will drive costs through the roof and destroy profitability.
The cheapest suggested astronaut beyond-moon mission costs $150 billion,
15 times your suggested budget, and requires on native propellant from
the Martian atmosphere, not available on asteroids unless we find metal
and ice on the same rock.  The equipment tech is much more important,
and almost totally ignored by NASA.

Meanwhile, we can go a long ways by bootstrapping volatiles, which can
be processed using much lighter and simpler pieces of equipment with
a much higher thruput -- purifying propellant out of ices and extracting
propellant from the Martian atmosphere being two exemplars.  Propellant
and tank (ice has a zero tankage factor) make up over 90% of the mass
needed to get out to the asteroids and back. Once we have cheap propellant, 
it becomes much easier to get that heavy equipment out to the asteroids, 
and get the payload back, and volatiles for lubricant and cooling make 
it much easier to design and operate that equipment.  And shielding and 
life support, so we can finally afford astronauts!


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