From: joseph@gkcl.ists.ca (Joseph A. Beernink)
Subject: Re: Inflatable Space Stations - Why Not ?
Reply-To: joseph@gkcl.UUCP (Joseph A. Beernink)
Organization: y
Date: Thu, 20 Aug 92 12:32:29 GMT

In article <1992Aug20.121234.17745@ists.ists.ca> joseph@gkcl.ists (Joseph A. Beernink) writes:
>In article <1992Aug19.183403.1527@gnv.ifas.ufl.edu> jrm@gnv.ifas.ufl.edu writes:
>>Whatever became of the idea of inflatable space habitats/workstations ?
>>The savings on initial cost and on launch weight should be very great.
>>Add to that the large size and configurational possibilities and you
>>have an incredibly good deal. Modern materials, esp tri-weave carbon
>>fiber, could strengthen an envelope and protect against ripping or
>>bursting. All you need is a docking hatch and a few hard points to attach
>>odds and ends to. The rest is just hot air. Internal partitions and
>>compartments would be easy to build into such a structure ... or glue in
>>later on. The large internal free volume of air would also add safety
>>against explosive decompression. Self-sealing layers could deal with
>>micrometeorites. If desired, thin interlocking plates of metal could be
>>attached to the envelope to armor the whole thing. 
>>
>>What's the problem ? Is this perhaps a TOO CHEAP solution - meaning that
>>the contractors couldn't steal enough money during development ? If we
>>want nice BIG space stations, with loads of internal room, with easy
>>expandability ... inflatable spheres sound like the economical solution.
>>Any feedback on this ?
>>
>>-- Jim Mason 
>
>I was tossing this idea around last summer, and discussed with a few
>physics and space science professors here at York U.  There are a few 
>major problems, the way I understand it.  
>1.  Many of the materials we would like to use, are 'biodegradable' in
>space.  They tend to be broken apart easily by radical oxygen and other
>compounds floating about in LEO.  Something like .1 - 3 cm thickness per
>year for somethings. (Just off the top of my head)  Needless to say,
>at the upper limit of this decomposition, many structures would not
>last ten years.
>
>2.  Blowing up the 'balloon' in space means dealing with radical pressure
>differences, trying to create an volume of gas in a vacuum, and expecting
>to stay where you put it is not an easy task.  Thus, the material would
>probably have to be as strong as kevlar, or the like.
>
>3.  The material would also have to be able to deal with the rapid
>fluxuations in solar radiation.
>
>Now don't get be wrong.  I am by no means an expert on any of this. (As
>certain people on the net will be quick to point out), and I would
>love to see this get started (hell I'd love to work on it), but
>according to my professor friends, its just not possible now.  But
>maybe things have changed.  I know they pulled down a satellite carrying
>materials research projects, but I have heard too much about that.
                                     not^    
>If someone who has heard could post the news, I'm sure many people would
>be appreciative.

Sorry about the mistake - will happen again.
                           not^
------------------------------------------------------------------
Joseph A. Beernink             | "Failure isn't a reason to quit...
joseph@gkcl.ists.ca            | it's a reason to try harder." me
cs921031@dialup.ariel.yorku.ca | (416) 739 1975 - York U. Toronto, Ont.
Newsgroups: sci.space