Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V13_3/V13_399.ZIP/V13_399

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Subject: SPACE Digest V13 #399

SPACE Digest                                     Volume 13 : Issue 399

Today's Topics:
      Re: At what time and date does the shuttle Atlantis land ?
             Re: Space technology
              Re: SPACE Digest V13 #364
          Teflon (Was Re: Space technology)
        Re: Teflon (Was Re: Space technology)
        Re: comsat cancellations and lawsuits
               Re: anniversary
               Re: anniversary
        Re: comsat cancellations and lawsuits
              Re: SPACE Digest V13 #344

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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Date: 8 Apr 91 19:16:41 GMT
From: usc!jarthur!nntp-server.caltech.edu!iago.caltech.edu![e-mail]  (Horowitz, Irwin Kenneth)
Subject: Re: At what time and date does the shuttle Atlantis land ?

In article <[e-mail]>, [e-mail] (Rene Schaad) writes...
>
>I know that the shuttle is supposed to land at Edwards AFB on wednesday.
>But when exactly? I would be glad if someone knowing the time could
>post it here.
>
>rene schaad
>--
>Rene Schaad
>Theoretical Neurobiology Facility, UC Irvine, California
>[e-mail]

The shuttle will be landing at approx. 7:35 a.m. PDT on Wednesday.
-------------------------------------------------------------------------------
Irwin Horowitz                        |"Suppose they went nowhere?"-McCoy
Astronomy Department                  |"Then this will be your big chance
California Institute of Technology    | to get away from it all!"-Kirk
[e-mail]               |       from STII:TWOK
[e-mail]                 |
-------------------------------------------------------------------------------

------------------------------

Date: 12 Apr 91 22:45:32 GMT
From: [e-mail]  (Eugene Miya)
Subject: Re: Space technology

In article <[e-mail]>
[e-mail] (Robert W Murphree) writes:
>>I like what Carl Sagan said, if you want to develop non-stick frying pans
>>you're better off funding a program for developing non-stick frying pans
>>99% of the time(rather than a program for sending box cars with men in them
>>to space).

Justifying the space program on the basis of spinoffs does not cut it.
I know this because I've been to Capitol Hill.  The problem is simply that
you cannot justify funds in this country solely on the basis of the unknown.

I have an objective X, call it going to the moon, Mars, Jupiter, what ever.
Justifying that travel on the basis of spinoff Y simply clouds the issue
of X.  Let's say I'm going to discover Y tomorrow.  If I don't know what
Y is, there are limits, Y is a diversion from X.  It becomes promoting Y.
NASA despite ideas to the contrary, is not a research organization.
It is at best a "systems integator."  That's not my term, but it is what I
am told again and again.  We just happen to have "Research Centers" and
a little gets done.  The NSF is where most basic research gets funded in
this country (or DARPA if you hear the Japanese).

Teflon (trademark duPont) was not developed for or by the space program.
Similar compounds are used in Uranium diffusion.  This is a fallacy
perpetrated by some well-meaning supporters of NASA.

--e.n. miya, NASA Ames Research Center, [e-mail]
  Resident Cynic, Rock of Ages Home for Retired Hackers
  {uunet,mailrus,most gateways}!ames!eugene

------------------------------

Date: 12 Apr 91 21:37:53 GMT
From: swrinde!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!helios.physics.utoronto.ca!aurora.physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: SPACE Digest V13 #364

In article <[e-mail]> [e-mail] writes:
>in article <[e-mail]>, [e-mail] (Gary Coffman) writes:
>> In article <[e-mail]> [e-mail] writes:
>>>Re: E.T.'s
>
>>>Another problem is;  What if the guys you find don't think of us as enemies, or
>>>even potential slaves, but FOOD?  No thanks!
>>>There is the argument, tho, that since we have now advertised our presence to
>>>the surrounding 60 ly sphere in space (TV started in 1936), we should at least
>>>find out if we are attracting unwanted attention that we should prepare for.
>>
>Recall who the star of the very first TV broadcast was? Adolph Hitler, opening
>the 1936 Olympics.
>
   Have we been reading Carl Sagan's science fiction books? I believe
that if you reread the text you'll see that Adolf Hitler did appear in
the highest power transmission to that date, though I hesitate to use
science fiction as a historical reference. It was not claimed that he
appeared in "the very first [public?] TV broadcast."
   Anyway, think about it. Television was developed in the USSR and in
the United States, so it seems unlikely that the first public broadcast
took place in Germany. I've got some vague memory that the Nazi party
went to considerable pains to see that televisions were relatively
common around Berlin for the propaganda value when the world's people
came to see the Olympics. This 'fact' might also be from Sagan's book,
though.


--
 Christopher Neufeld....Just a graduate student  | Flash: morning star seen
 [e-mail]    Ad astra! | in evening! Baffled
 cneufeld@{pnet91,pro-cco}.cts.com               | astronomers: "could mean
 "Don't edit reality for the sake of simplicity" | second coming of Elvis!"

------------------------------

Date: 12 Apr 91 09:10:18 GMT
From: unmvax!nmt.edu![e-mail]  (Daniel Briggs)
Subject: Teflon (Was Re: Space technology)

In article <[e-mail]> [e-mail]
 (Phil OKunewick) writes:
>   Teflon probably wouldn't even have been invented if NASA hadn't
>needed a slippery, heat-resistant, abrasion-resistant, non-conductive
>material.  Matter of fact, the government spending millions of dollars
>to develop a non-stick frying pan would most likely have been labeled
>a huge waste of taxpayers money; thus the program would have probably
>been killed after a few million had been spent, but before there were
>any usable results.  But once the material was developed, it became
>clear that the uses for this stuff were endless.

Hmmmm.  While I agree with much that has been said about spinoff
technology, perhaps the example of teflon isn't a good one.  I was
under the impression that teflon was one of the great serendipitous
discoveries of modern science.  Unfortunately, I don't have a written
source for this fact, as I heard it in a public lecture given by Glenn
Seaborg.  His credentials are pretty good, but it's been a decade or
so since I heard it.  If anyone can post a hard reference to the
story, I'd love to see it!

As I recall, Seaborg brought up the story to illustrate the benefits
of careful work, and recognizing the unusual when you see it.  The lab
where the stuff was discovered was in fact involved with the synthesis
of unusual materials.  In the course of this, it used a great many
canisters of some gas.  (I think it was oxygen, but the memory is
dim.)  In the course of normal record keeping, it was revealed that
one expended canister weighed more than it should.  This indicated
that some sort of contamination leading to a reaction has taken place
in the canister, and presumably corrupted it.  Normally, such a
canister would simply be tossed out and written off.  Apparently a
researcher on his own initiative probed the thing and got a sample of
the goo that had formed in it.  It seemed interesting, and he tested
some of its properties in the lab after hours.  When the breakdown
temperature proved to be very high, he got interested and did a full
analysis.  It was indeed teflon, and they were very interested in
making more of it.  Unfortunately, tracking down the reaction that had
produced it turned out to be quite difficult, and for a while they
weren't sure they could do it.  The critical factor finally turned out
to be the presence of the silver gasket in the original canister.
(Yes, that's what he said.)  By a really unlikely coincidence, this
was the catalyst that was needed to make the reaction happen at
reasonable temperatures.

Now this maybe should go in sci.physics.folklore, since I could well
have hashed most of the details, but I think the fact is that the
discovery of teflon was largely an accident by some chemist types who
kept their eyes open.  Even if the lab turns out to have been a NASA
one, it probably wasn't a substance produced on demand according to
NASA specs.  Even though non-stick frying pans are often used as an
example of spin-off technology, maybe teflon itself isn't such a good
example.  Anyone with more details care to correct me or give the full
poop on the story?

--
This is a shared guest account, please send replies to
[e-mail] (Internet)    [phone]
Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801  (U.S. Snail)

------------------------------

Date: 12 Apr 91 18:49:07 GMT
From: eagle!mars.lerc.nasa.gov![e-mail]  (Amitava Banerjea (KSU))
Subject: Re: Teflon (Was Re: Space technology)

In article <[e-mail]>, [e-mail] (Daniel Briggs) writes...
>In article <[e-mail]> [e-mail]
> (Phil OKunewick) writes:
>>   Teflon probably wouldn't even have been invented if NASA hadn't
>>needed a slippery, heat-resistant, abrasion-resistant, non-conductive
>>material.
>
>perhaps the example of teflon isn't a good one.  I was
>under the impression that teflon was one of the great serendipitous
>discoveries of modern science.

>If anyone can post a hard reference to the
>story, I'd love to see it!

Glad to oblige!

From C. A. Sperati and H. W. Starkweather, Jr., Fortschr. Hoshpolym.-
Forsch., Vol. 2, p. 465 (1961):

In Sec. II, entitled "Synthesis and Polymerization of Tetrafluoroethylene" --
that's the technical name for Teflon -- "poly-tetrafluoroethylene",
starting on p.468

"The first report of the polymerization of tetrafluoroethylene was by Plunkett
in 1941, who had a cylinder of TFE cut open to see why the expected amount
of gas was not released when the valve was opened. His perspicacity led to
the discovery of an inert, white, opaque solid with a waxy feel. Various methods
polymerization were tried after the adventitious discovery and . . ."

The section goes on to describe current methods of producing PTFE (Teflon)
and its various physical and chemical properties as they were known at the
time. It is a good review article to launch a technical inquiry about Teflon.
Plunkett's original reference is "Tetrafluoroethylene polymers, U. S. Patent
2,230,654 (Feb. 4, 1941)". I haven't bothered to look it up.

>Unfortunately, tracking down the reaction that had
>produced it turned out to be quite difficult, and for a while they
>weren't sure they could do it.  The critical factor finally turned out
>to be the presence of the silver gasket in the original canister.
>(Yes, that's what he said.)  By a really unlikely coincidence, this
>was the catalyst that was needed to make the reaction happen at
>reasonable temperatures.

Interestingly, S & S do not include silver in the list of preferred
reaction initiators, although high pressures, as must have existed in
the cylinder are needed. They mention "adueous media" and oxygen is
mentioned as one of the preferred initiators. It is possible, I'm
guessing here, that the gas in the cylinder was not entirely dry or pure.
If it was contaminated with both moisture and oxygen, and sat around for
a long time, that might explain the reaction. BTW, the starting gas, TFE
is rather explosive at high temperatures and pressures.

>Even if the lab turns out to have been a NASA
>one, it probably wasn't a substance produced on demand according to
>NASA specs.

Plunkett, the original discoverer, worked for DuPont and DuPont owned (still
owns?) exclusive manufacturing(?) rights to Teflon. Subsequent development and
use of Teflon may have been promoted by government/defense/NASA funding but I
have no details on that. The trick in making non-stick frying pans is to get
the pan to stick to Teflon as *nothing* sticks to Teflon!!

Bye

Amitava
_____________________________________________________________________
Amitava Banerjea
[e-mail]
       ^^^^^^==or mars or saturn
_____________________________________________________________________

------------------------------

Date: 12 Apr 91 18:13:47 GMT
From: agate!bionet!uwm.edu!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: comsat cancellations and lawsuits

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

>Still sounds like grounds for a lawsuit to me.  *What* "best endeavours"?

I thought there was only going to be one Endeavour.

Is Endeavour II already in the works?

--
Phil Fraering
[e-mail]
"The reserve of modern assertions is sometimes pushed to extermes, in
which the fear of being contradicted leads the writer to strip himself
of almost all sense and meaning." - Winston Churchill, _The Birth of
Britian_
"X-rays are a hoax." - Lord Kelvin

------------------------------

Date: 12 Apr 91 20:29:56 GMT
From: pacbell.com!mips!sdd.hp.com!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utgpu!watserv1!watnow.waterloo.edu![e-mail]  (Mark Earnshaw)
Subject: Re: anniversary

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>Lest we forget, today is the 20th anniversary of the first man in space.

Oops, that should be the 30th anniversary.  And isn't it almost exactly 10
years since Columbia first flew?

--
Mark Earnshaw, Systems Design Engineering   |    [e-mail].{edu,cdn}
University of Waterloo, Ontario, Canada     |    [e-mail]

------------------------------

Date: 12 Apr 91 20:59:32 GMT
From: agate!bionet!uwm.edu!spool.mu.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: anniversary

In article <[e-mail]> [e-mail] (Mark Earnshaw) writes:
>>Lest we forget, today is the 20th anniversary of the first man in space.
>
>Oops, that should be the 30th anniversary...

Oops indeed.  30th it is.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

------------------------------

Date: 11 Apr 91 00:06:24 GMT
From: hub.ucsb.edu!ucsbuxa![e-mail]  (Charles Frank Radley)
Subject: Re: comsat cancellations and lawsuits



The a satellite rescue you mean is presumably Intelsat-6, it is
the only one scheduled as far as I know, I think it is Feb 1992..
It is the first flight of Endeavor.    The satellite is ownded
by Intelsat, it was manufactured by Hughes.   Intelsat was
also hit hard bvy NASA's termination of Shuttle launch
contracts, Hughes' suit could open the floodgates...
  NASA never guaranteed to launch anything.
The language in the standard Launch Services Agreement
states NASA will use "their best endeavours", which
means no warranty etc.

------------------------------

Date: 11 Apr 91 18:11:15 GMT
From: ssc-vax!bcsaic!hsvaic![e-mail]  (Dani Eder)
Subject: Re: SPACE Digest V13 #344

In article <[e-mail]> [e-mail] (Donald Heskett) writes:
>
>IMHO it's a very poor idea to complicate your launch system that much
>for a mere 300mph.
>

According to Dr. Dana Andrews of Boeing, who is the study manager of one
of the four industry SSTO studies underway for the SDIO, the addition of
1000 feet/second (680 miles per hour) to a horizontal take-off SSTO rocket
that uses oxygen/hydrogen propulsion will triple the payload.

This is because SSTO vehicles using chamical propulsion are today just
this side of feasibility, and so are very sensitive to how much velocity
they have to provide.  So in this case, a relatively small ground accelerator
can have a large effect on payload capacity.

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End of SPACE Digest V13 #399
*******************