HDTenEightyP/NetNews huggingface dataset:
From: joseph@gkcl.ists.ca (Joseph A. Beernink)
Subject: Re: Inflatable Space Stations - Why Not ?
Reply-To: joseph@gkcl.ists (Joseph A. Beernink)
Organization: York University, Toronto, Ontario
Date: Thu, 20 Aug 92 12:12:34 GMT

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.
If someone who has heard could post the news, I'm sure many people would
be appreciative.
------------------------------------------------------------------
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.
From: evert@CPSnet2.cps.edu (Mike Evert)
Newsgroups: sci.space
Subject: Electric Tethers
Date: 19 Aug 92 00:54:10 GMT
Article-I.D.: cs.Bt7H6x.13z.1
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

I have a question about the possibilites of an electric tether system
like that the recent shuttle flight attempted to test.

As I understand it, if a current is put into the tether, then that
would cause the tether and spacecraft to gain kenetic energy and rise
to a higher orbit.  The opposite will happen if current is drawn from
the tether.  Would the acceleration always be in one direction and its
reverse only?  I don't know if this would be in the direction of orbit
or perpindicular to magnetic field.  Is it possible to use the tether
for lateral motion?

It seems possible to put a payload into a high orbit at a cheaper cost
by launching the payload into low orbit.  If that payload carried a
solar powered tether system (or if it could rendevous with one already
in orbit), then the tether can be used to boost the payload the rest
of the way for nearly free.

Now if a tether system could accelerate a spacecraft in a lateral
direction, then you could go anywher in orbit with them.  You could
launch Energyas from CIS at their high lattitudes and use tethers to
make the orbital corrections needed to send them to FRED or to
geosync or anywhere else.  But alas I don't even know if it is
possible.

Regardless, I think tethers have such possibilities that the
government should divert all social program money to their
development.  Well maybe some of that money could also be diverted
to DCX/DCY, NASP, solar sails and any other super great investment
opportunities that come our way.

Thank you,

Mike


-- 
+----------------------------------+---------------------------------------+
|  Mike Evert                      | "You are helplessly hypnotized.  You  |
|  Internet: evert@CPSnet2.cps.edu |  will believe everything I tell you.  |
|    Delphi: LordMike@delphi.com   |  This quoted message does not exist." |
+----------------------------------+---------------------------------------+
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.space
Subject: Re: Energya and Freedom and Soyuz ACRV and...
Date: 14 Aug 92 13:03:34 GMT
Article-I.D.: ke4zv.1992Aug14.130334.8888
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <16aaa5INNlav@agate.berkeley.edu> gwh@soda.berkeley.edu (George William Herbert) writes:
>
>	Ok, we now have 4 potential solutions (HL-20, Soyuz, 2xPLS above);
>Soyuz is $65 million per flight and $500 million to adapt (massively

This is a questionable number. CIS is now quoting commercial launches
on Proton for $65 million, not including payload, and the US and others
are complaining that that is a below cost figure and unfair trading
practice. The US wants them to charge $85 million like Arianne. Now
add in the cost of a new Soyuz capsule for each flight to get a realistic
number.

>	As you've said, neither PLS nor HL-20 is going to Phase B anytime
>soon, though it's easy to point out that if they don't, we won't have
>a ACRV for PMC Freedom (or for several years later 8-( ).  NASA gets
>half credit for knowing it needs one and fails the exam for not
>acknowledging it and trying to solve the problem by the time the need is
>real... 8-(

But we will have long duration Shuttles by the time of PMC. So the
Shuttle can be crew transport, resupply, material return, and ACRV 
until we get something better. Not great, but workable with the current
fleet. We also get the use of the docked Shuttle's middeck and Canadarm
at no extra cost.

Gary
Newsgroups: sci.space
From: schmasey@leland.Stanford.EDU (Casey Carlton O'Hara)
Subject: Re: Deep-sea Diving on Europa
Organization: DSG, Stanford University, CA 94305, USA
Date: Sun, 16 Aug 92 01:53:43 GMT

In article <1992Aug15.073439.25744@news.iastate.edu> barrett@iastate.edu (Marc N Barrett) writes:
>
>   I have heard that Europa's oceans are quite a lot deeper than the oceans
>on Earth, even though Europa is a much smaller world.  My question is: do we
>have any deep-sea diving equipment that could survive the great pressures 
>that exploration of the bottoms of the Europan oceans would entail?  I know
>that the Mariana Trench on Earth has been visited before, but that trench is
>only eight or so miles deep, which is nothing compared to the figures of 20
>or more miles that I have heard bandied about for the possible depth of the
>oceans on Europa.  

The formula for hydrostatic pressure (the pressure exerted by a fluid
due to the weight of the fluid above it) is something like:
	p(h) = p(a) + d*g*h
where p(h) is pressure at depth h, p(a) is atmospheric pressure, d is
depth below surface, and g is acceleration due to gravity.  

I have NO clue about the value of g on Europa, but I'll assume it's
less than that on Earth's moon, which is about 1/6 that of Earth's
gravity.

Also, Europa's atmospheric pressure is probably pretty low, but that
term is usually pretty small anyway.

Anyway, assuming g(Europa)=g(Earth)/6, water 20 miles deep on Europa
would exert as much pressure as water about 20/6 or 3.33 miles deep on
Earth.  So, no problem there.  The real problem would be getting all
that shit to Europa in the first place.  
Wow, I'm actually applying stuff I learned in class.  Probably
applying it wrong, though.  
>--------------------------------------------------


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~   __________/  bonz R godz!  ~~~~~~~~~~~~~~~~~
Casey O'Hara			  (_|____|___\__________
schmasey@leland.stanford.edu             _|_|___________)
Disclaimer:  All opinions expressed here are yours.   ~~~~~~~~~~~~~~~~~~~~~~~~~
From: roberts@phoenix.ocf.llnl.gov (Don Roberts)
Newsgroups: sci.space
Subject: Re: He3 Power Source
Date: 17 Aug 92 15:56:55 GMT
Organization: Lawrence Livermore National Laboratory

sth@slipknot.mit.edu (Scott Hannahs) writes:
>
>Any reason the moon should be richer in 3He than the earth? The natural
>abundance of 3He is about 7ppm in regular 4He which is from trapped
>alpha decay in natural gas wells. [...]
>The major (only) commercial source of 3He (~$90 >US / liter STP federal
>research grant rates) is from nuclear weapons manufacture. [...]
>Now that the arms race is over all the low temp physicists should start
>worrying about the availability of 3He. For awhile as warheads are
>deactivated things will be ok, but eventually....  No more research below
>1K.  We do recycle the stuff but nothing is 100% effecient.
>
>Scott Hannahs, F. Bitter National Magnet Lab, sth@slipknot.mit.edu

The only reason I've heard for high abundance of He3 on the moon is the
solar wind. With neither a magnetic field nor an atmosphere, the moon
just scoops the stuff up, whereas the earth pushes it out of the way.

As for He3 from tritium decay, the condensed matter crowed better hurry
up and finish their low temperature research. There might be a fair bit
of tritium in the retired stockpile now, but there isn't *any* new
tritium being produced. In the (unlikely) event that we get D-T fusion
working in the next 12.32 years (to pick a number out of thin air :),
you won't even have much of *that* to play with.

--
 Dr. Donald W. Roberts
   University of California                                      Physicist
   Lawrence Livermore National Laboratory         Recreational Bodybuilder
   dwr@llnl.gov                                       (better poo? :)
From: Frederick.A.Ringwald@dartmouth.edu (Frederick A. Ringwald)
Newsgroups: sci.space
Subject: Re: Star Trek (anti-)realism
Date: 23 Aug 92 04:58:07 GMT
 <2PgXPB9w165w@clubzen.fidonet.org>
Organization: Dartmouth College, Hanover, NH

In article <2PgXPB9w165w@clubzen.fidonet.org>
mwallis@clubzen.fidonet.org (Michael Wallis) writes:

> > DP>In response to the statement that no real navy would let a 35 year captain
> > DP>a ship. Reference Captain John Paul Jones US or Colonial navy during
> > DP>the US revolutionary war, I'm pretty sure he was around 35 when he got
> > DP>his first command.
[...]
> > John Paul Jones was 21 when he first took command of a vessel.  He was
> > en route to Scotland as a passenger when both skipper and 1st mate died
> > of fever.
> 
> I don't have his name handy, but there's a Canadian Navy Captain of a
> submarine who made Captain at age 25. He had join at age 17, worked and
> studied hard and made rapid progress up the command chain in 8 years.

Grrr. Read the original post, will you people ?!? John Paul Jones got
where he was during a WAR, during which there is not much EXPLORATION;
and when he was 21, he certainly didn't retain command after they
reached port. Furthermore, a submarine is not a CAPITAL SHIP: it's
still technically a boat, despite the dramatic increase in capability
nuclear power gives it. Does this Canadian officer have the rank of
Captain, or do they just call him that because he commands a vessel?
Old custom, you know. (If a second officer with the rank of Captain
comes aboard, it's customary to call him "Commodore" while he is
aboard, the rationale being no ship can have two captains. This goes
even on a lowly corvette with a Lieutenant commanding; and while aboard
his vessel, you'd better call him Captain!) And does he command a
diesel or nuclear submarine? If it's diesel, it's definitely a BOAT,
not a CAPITAL SHIP, the diffference being greater than that between a
pickup truck and a semi-trailer.

This topic is silly anyway and the matter should drop, and besides, no
one with real experience in a real navy will dispute the original post.
Newsgroups: sci.space
From: aws@iti.org (Allen W. Sherzer)
Subject: Re: Energiya's role in Space Station assem
Organization: Evil Geniuses for a Better Tomorrow
Date: Sun, 16 Aug 1992 20:29:21 GMT

In article <1992Aug16.135754.19274@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:

>>>Name *one* major military procurement that
>>>proceeded on a fixed price basis with *no* adjustments. 

>>The ATF prototype...

>None of these are *procurement* contracts. They are R&D proposals.

LACE, RME, and the associated launches where procurements. However,
if you want other examples, I know of several procurements of HARM
missiles which where delivered at less than the agreed upon price. In
addition, there is the Endeavour purchase as well as several launch
service contracts I know of.

>NASA currently can't sign a guarrantee that it will buy a fixed number
>of anything over a multi-year period because Congress only funds 
>NASA year by year.

Nonsense. NASA has a number of agreements for luanchers which streach over
several years. The Air Force which faces even harder constitutional limits
on funding recently bought a ten year supply of Titan missiles.

In addition, we are desling with a station which does need resuply. The
market IS there if NASA will open it up. 

  Allen
-- 
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "If they can put a man on the Moon, why can't they     |
|  aws@iti.org     |  put a man on the Moon?"                               |
+----------------------250 DAYS TO FIRST FLIGHT OF DCX----------------------+
From: clements@vax.oxford.ac.uk
Newsgroups: sci.space
Subject: Re: Germans drop European Shuttle ?
Date: 12 Aug 92 10:38:46 GMT
Organization: Oxford University VAX 6620

In article <pgf.713577979@srl02.cacs.usl.edu>, pgf@srl02.cacs.usl.edu (Phil G. Fraering) writes:
> <RFLOOD@ESOC.BITNET> writes:
> 
>>Whilst skimming thru the TV channels last week, I caught sight of the
>>German research minister, Riesenhuber, saying that Hermes was 'unacceptable'
>>(not exact translation) to the German government in either manned or unmanned
>>form. Two days later he showed up at the European Space Operations Centre to
>>congratulate senior management on the fine job they'd done on Eureca. I'm
>>cynical enough to believe that when politicians start throwing praise around,
>>one should watch one's back. The ESA ministerial conference in November will
>>probably contain some nasty surprises.........
> 
> Hey! He's probably just tired of the way the French have shut down all
> launch vehicle research besides Hermes/Ariane V in ESA...
> 
> To wit, Saenger and Hotol...

HOTOL and, as far as I know, Sanger were never properly adopted ESA projects.
They were national or corproate schemes proposed to ESA as possible future
launchers, which ESA didn't take up (mores the pitty).

Sanger, I think, died there and then, but HOTOL continued as a British
Aerospace project, though they had to drop Alan Bond's air breathing rocket
motors since Rolls Royce, who owned the patent, refused to do anything without
government/ESA support. Thus was born the Interim HOTOL, which would use a
modified HOTOL airframe with conventional motors, lifted to altitude by an
Antonov 225 (the plane tht carries bits of Energia around) also modified to
give it extra thrust (extra engines added). This project was in conjunction
with the USSR/CIS/whatever.

Now, though, British Aerospace have closed down their Space Systems division in
Stevenage, where the project was based, and so this scheme too would appear to
have died.

And thats the way the British 'space industry' operates.

-- 
================================================================================
Dave Clements, Oxford University Astrophysics Department
================================================================================
clements @ uk.ac.ox.vax			|  Umberto Eco is the *real* Comte de
dlc      @ uk.ac.ox.astro		|           Saint Germain...
================================================================================
From: mwallis@clubzen.fidonet.org (Michael Wallis)
Newsgroups: sci.space
Subject: Re: Star Trek (anti-)realism
Date: 22 Aug 92 21:40:24 GMT
Organization: Club Zen BBS - Fidonet/Internet - +1 408 734 2289

Chris.Ralph@f573.n635.z3.fidonet.org (Chris Ralph) writes:

> DP>From: parkins@theory.TC.Cornell.EDU (David Parkins)
> DP>Organization: Cornell Theory Center
> 
> DP>In response to the statement that no real navy would let a 35 year captain
> DP>a ship. Reference Captain John Paul Jones US or Colonial navy during
> DP>the US revolutionary war, I'm pretty shure he was around 35 when he got
> DP>his first command.
> 
> DP> * Origin: FidoNet/ACSNet Gateway [csource.oz.au] Melbourne, OZ
> (3:632/400.0)
> 
> John Paul Jones was 21 when he first took command of a vessel.  He was
> en route to Scotland as a passenger when both skipper and 1st mate died
> of fever.

I don't have his name handy, but there's a Canadian Navy Captain of a
submarine who made Captain at age 25. He had join at age 17, worked and
studied hard and made rapid progress up the command chain in 8 years.

------------------------------------------------------------------------------
mwallis@clubzen.fidonet.org - Michael Wallis
Newsgroups: sci.space
From: mheney@access.digex.com (Michael K. Heney)
Subject: Re: Beanstalks in Nevada Sky (was Re: Tethers)
Organization: Express Access Online Communications, Greenbelt, MD USA
Date: Wed, 12 Aug 1992 17:44:54 GMT

In article <1992Aug12.152900.19426@pixel.kodak.com> dj@ssd.kodak.com (Dave Jones) writes:
>
> [...]
>
>Clarke also had his tower made of that famous variety of unobtainium,
>monomolecular filament.  Assuming he'd done some basic estimates, you
>have to figure that's the kind of tensile strength you need for a cable
>23,000 miles long.  He also had a captured asteroid stuck out on the
>far end as a counter-weight, possibly at a height beyond GEO.
>

Don't forget the _2061: Odyssey Three_ approach - diamond.  I know diamond
is used in presses to generate pressures in the millions of atmospheres
(in very *small* volumes), but is it actually strong enough to handle the
tensile forces a GEO-centered tether would need to handle?

Also, given a properly counterweighted system, so that the cm (or is it
cg?) is at GEO, and the bottom of the tower nuzzles gently on the ground,
wouldn't orbital perturbations really mess things up in a hurry?  Given
the masses we're talking about, stationkeeping would be quite a problem,
no?


Mike Heney               | Looking for Senior level technical | Reach for the 
mheney@access.digex.com  | and administrative positions world | Stars!!!
Kensington, MD (near DC) | wide.  Call me.                    |

Newsgroups: sci.space
From: knapp@spot.Colorado.EDU (David Knapp)
Subject: Re: Seeding Mars with life
Organization: University of Colorado, Boulder
Date: Fri, 14 Aug 1992 01:55:50 GMT

In article <1992Aug12.142537.10350@csi.on.ca> richard@csi.on.ca (Richard Martin) writes:
>In article <9208120143.AA07834@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes:
>>
>>-From: knapp@spot.Colorado.EDU (David Knapp)
>>-Subject: Re: Seeding Mars with life
>>-Date: 11 Aug 92 15:38:58 GMT
>>-Organization: University of Colorado, Boulder
>>-In article <20625@sbsvax.cs.uni-sb.de> dietz@cs.rochester.edu writes:
>>->Even the "vent" organisms are exploiting the chemical gradient set up
>>->by photosynthesis (they oxidize the reduced chemicals coming out of the
>>->vents), and are therefore not completely geothermally powered.
>>
>>-The do not comsume photosythesized materials. (at least according to National
>>-Geographic...)
>>
>>I think the point Paul's trying to make is that the organisms take advantage
>>of oxidizing chemicals (perhaps oxygen among them) produced by photosynthetic
>>life. I don't know enough on the subject to confirm or deny that. I have
>>read that some bacteria get their energy by some chemical change in iron
>>compounds, and that others get it by converting one sulfur compound to another,
>>and it would be helpful if Paul would comment on whether both of these are
>>tied in with compounds produced by photosynthesis.
>>John Roberts
>>roberts@cmr.ncsl.nist.gov
>Please forgive me if I make any glaring errors, but I have read about a type
>of bacteria which carries out anaerobic respiration. 


Would that be botulism?




-- 
David Knapp                                      University of Colorado, Boulder
Highly Opinionated, Aging  and                      knapp@spot.colorado.edu
Perpetual Student of Chemistry and Physics.
            Write me for an argument on your favorite subject.
Newsgroups: sci.space,sci.astro
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Subject: Mars Observer Mated to Titan III Rocket
News-Software: VAX/VMS VNEWS 1.3-4   
Keywords:  Mars Observer, JPL, KSC
Reply-To: baalke@kelvin.jpl.nasa.gov
Organization: Jet Propulsion Laboratory
Date: Sat, 22 Aug 1992 05:22:56 GMT

          George Diller                                     August 21, 1992
          Kennedy Space Center
          407/867-2468

          Bob MacMillin
          Jet Propulsion Laboratory
          818/354-5011

          KSC Release No. 111-92

          MARS OBSERVER MOVED TO LAUNCH COMPLEX 40 AND MATED TO TITAN III

               The Mars Observer spacecraft passed another milestone toward
          launch when it was moved from the Payload Hazardous Servicing
          Facility on Kennedy Space Center to Launch Complex 40 on Cape
          Canaveral Air Force Station and mated to the Martin Marietta
          Titan III rocket.  With the payload atop the launch vehicle,
          checks of the Mars Observer spacecraft and the attached Transfer
          Orbit Stage (TOS) will begin this weekend.

               Two major exercises to prepare for launch are on tap for
          next week.  An Operational Readiness Test on Aug. 26 will test
          all facilities that send and receive data during flight
          activities.  These include NASA, JPL, and Air Force tracking and
          data systems around the world.

               A countdown dress rehearsal on Aug. 28 will simulate launch
          day activities and all countdown events as closely as possible.
          The mobile service tower will be retracted from around the launch
          vehicle, and the full NASA, Martin Marietta and Orbital Sciences
          launch team will participate in this exercise.

               All activities currently are on schedule to support a launch
          at the opening of the Mars planetary opportunity on September 16.
          The launch window extends from 1:02 to 3:05 p.m. EDT.

               Mars Observer will be the first U.S. mission to Mars since
          the Viking program in 1975.  From a circular Martian polar orbit
          of 250 miles, it will create a detailed global portrait of the
          planet.  The spacecraft will map the surface and study Mars
          geology while profiling its atmosphere and weather.  The mission
          is designed to span one Martian year, or 687 earth days.

                                          # # #
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | baalke@kelvin.jpl.nasa.gov
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Optimists live longer
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | than pessimists.
|_____|/  |_|/       |_____|/                     |