Every bit of the cow gets used

Mike Combs wrote,

"I earlier said that the first prototype SPS, or perhaps even the first half dozen, wouldn't justify use of space resources. "

I read an article in Discover magazine recently about the complete usage by industry of every part of the cow. Meat and leather are just the beginnings of the usage of cattle. There are hundreds of other uses for different parts of the cow. Nothing goes to waste. Even the snout gets used to produce pharmaceuticals!

One thing about which I've been thinking recently is that any type of space resource mining operation is likely by necessity to be a multi-product facility. Much like a cow, I believe that every last pebble of a returned meteoroid would be put to some use. The setup costs are simply too high to leave anything to waste. If the initial goal of the operation were to construct large portions of an SPS from extraterrestrial materials, then it would be likely that large proportions of the asteroid would be unusable for that purpose. But the parts that are not usable for structural purposes could be used in other ways, for example, propellant production, return of platinum group metals (PGMs) to Earth, radiation and impact shielding, etc.

My point is that if there were a space resource facility of the scale necessary to construct large portions of an SPS from extraterrestrial materials, that there would also be many ancillary products that such a facility could produce and use or sell. These ancillary activities would have economic value as well. One might not be able to justify the construction of a space resource utilization facility based solely on the return of PGMs to Earth, but return of PGMs to Earth might be one of several supportable activities in which a space resource utilization facility could engage.

I think that we should think about stressing the multi-product aspect of space resource utilization. We should try to envision the complete set of different value propositions that a space resource utilization facility could provide to a variety of users. If we stress only SPSs, then we do not convey that there may be other usages to which extraterrestrial materials might be profitably put.

Ron Menich

"Combs, Mike"
09/21/01 09:24 AM

I don't see that. This can make sense in the very small scale too.
Many asteroids contain metals that can be separated by heating
alone.
I would dearly love for this to be right, as I'm pulling for use of space resources as soon as possible. But I remember discussing this topic with one fellow on Usenet who said that a mistake many space resource advocates make is the assumption that getting pure metals out of space ores is as simple as shining some concentrated sunlight on them. I promised him I would try to never make that mistake. It's certainly true that the ore reduction methods proposed in the original Summer Studies were quite complex, and involved a fair amount of chemical reagents. I happen to agree that those reagents can be reused, but I think ore reduction will always remain a complicated, multi-step operation, requiring significant infrastructure of considerable mass.
If you can capture an asteroid using small reusable
radio controlled ion drive probes it is a lot cheaper to get mass
that way than launching from earth.
Absolutely. And if using the mass for radiation shielding, say, that would just about be your only expense. But to make any product more complicated than that will require industrial infrastructure in space, and the expense of its emplacement must be factored into your costs. Now don't get me wrong, I'm strongly convinced that above a certain scale this is definitely the most economical way to go. But I think one can imagine a sufficiently small scale where the costs of boosting the necessary infrastructure still outweigh the lift cost savings of space resource use.

And I should clarify something. I earlier said that the first prototype SPS, or perhaps even the first half dozen, wouldn't justify use of space resources. I'm still of the opinion that even the first SPS should be built from space materials. Reason being that I don't think we should even consider building one or a half dozen SPS and then stopping. We shouldn't consider anything less than solving our global energy and greenhouse problems with SPS. And High Frontier is the most economical way to do that.

But if it came down to a Earth-launched prototype SPS, or no SPS at all because space resource use is "too risky", I'd vote for the SPS, and hope that once in an era of at least one functional SPS, we could get to High Frontier soon afterward.
I mean the ISS cost how many billion? How many DS1 class spacecraft
would you need to get a hundred tonnes? Not many; and most of
the cost of DS1 was the design.
Yes, but could we build something comparable to ISS with the small amounts of machine tools being discussed here?

Personally, I'll be turning hand-springs on the day we make radiation shields from raw space materials.

Regards,

Mike Combs