🚀 go-pugleaf

In article <1989Feb10.203043.14958@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:
>In article <119@beaver.cs.washington.edu> szabonj@fin.UUCP (Nick Szabo) writes:
>>>The robotic and tele-operated technology we _must_ have to establish
>>>and maintain a manned presence is not yet mature.
>>
>>The "must" is correct.  Sustained manned presence requires self-sufficiency...
>
>Why?  Name three settlements on *Earth* that are self-sufficient.

My message, in context, said *potential* self-sufficiency.  Any small
community that has farmland, woodland,  machine shops, and actual or 
potential access to local wind, solar, hydro, coal or oil, is potentially 
self-sufficient.  There are thousands of such communities on Earth.

Space settlements must be *more* self-sufficient, because the transportation
system from Earth to space is more complex and fragile.  How would dependent
space settlements fair if it were discovered that rockets destroy the ozone,
or if WWIII broke out (conventional or nuclear), if the powers controlling
the system decided there were more urgent priorities than spending billions
on distant space habitats, or (fill in your own bad-news scenario).  

>Clearly a colony needs either good recycling
>or local supplies for air and water, and local production of basic foods
>and structural materials is at least highly desirable.  

Agreed.  And we do *not* have the technology to do this.  We do not know
how to conduct mining or manufacturing operations in vacuum or less than
1 gravity.  It is still an expensive operation to scoop up a few ounces
of soil on Mars.  There are thousands of refining and manufacturing
operations that go into making structural materials from ore, and we do
not know how to do any of them in space.  We do not even know where we
can find good ore--the most likely source, asteroids, have never been 
explored due to lack of funding.  

These are the kinds of new technology and discoveries we need.  Spending
gigabucks putting a few lucky people in LEO does not teach us these things.
Exploring the length and breadth of the solar system, and working on   
advancing science and technology, is where we need to go.  

>If we assume that there is a useful amount of ice in lunar polar craters --
>not ridiculous but not at all certain either -- it clearly is possible to
>start a lunar colony with today's technology.  
>there was a proposal to do exactly that in 1992, as a commemoration of the
>500th anniversary of Columbus.  It would have been within reach of (major)
>private funding, given extensive reliance on donated labor and materials...
>but the reliance on six donated shuttle flights killed it.  

This is off by several orders of magnitude.  You can't put even one
space station module, with supporting solar cells, batteries, and 
several weeks of food, on the Moon, with six shuttles, even if we
had a lunar landing vehicle (a $5+ billion development in and of itself).
The estimates from NASA for a *minimal* lunar base: about 10 people huddled
in space station modules covered by dirt, with no mining or manufacturing
operations--run around $100 billion.  There have never been any reasonable
estimates made for mining operations on the Moon, whether they be the
alleged ice, LOX, or whatever, because we don't know how to build mining
eqipment that can operate in vacuum and high temperature and radiation 
extremes.  An ice-mining operation would increase the price-- and the base 
would still be nowhere near self-sufficiency, because all building materials, 
machines, parts, most food and chemicals except water would have to come 
from Earth.  Nor would such a base accomplish anything that could not be 
accomplished by unmanned vehicles for 100 times less expenditure ($20 billion). 


Nick Szabo              szabonj@fred.cs.washington.edu