Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V13_4/V13_404.ZIP/V13_404

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Subject: SPACE Digest V13 #404

SPACE Digest                                     Volume 13 : Issue 404

Today's Topics:
        Re: comsat cancellations and lawsuits
               Re:  Launch Technology:
             Re: Laser launchers
      Re: spacesuits (Was: Re: HST in-orbit Maintenance)
            new photovoltaic cell
  Re: Magellan achieves primary mission objective early (Forwarded)
        Re: Underground Nuclear Test in Nevada
              Re: SPACE Digest V13 #364
         Re: Space Stations, Money, Startrek
         Re: Space Stations, Money, Startrek
              Re: More cost/lb. follies

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]

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

Date: 13 Apr 91 18:14:54 GMT
From: sun-barr!ccut!wnoc-tyo-news!astemgw!kuis!rins![e-mail]  (will)
Subject: Re: comsat cancellations and lawsuits

In article <[e-mail]>, [e-mail] (Fraering Philip) writes:
>Trying to hold a fair and impartial trial, in which Hughes' suit may
>turn out to be frivolous (which I strongly suspect), seems to be the
>best way to go. Cynical realpolitic does seem fashionable sometimes, but
>the answer is probrably just to try to get back to an honest, impartial
>system. If nothing else, the "bad guys" know more about subterfuge and
>dirty tricks than the good guys, and are likely to "win" the case if a
>subjective interpretation of events instead of an objective trial is
>done anyway. This may sound strange, but maybe the answer to all of
>this corruption that is alleged to be going on in both government agencies
>and the corporations who seem to do most of their business with those
>agencies is less cynicism and more honesty.

    Well, I was'nt going say anything, but today i'm cynical. Now lets look
    at whats really going on (I think?).  Ok, now everyone knows that since
    Nixon, the U.S. goverment, has been going down hill.  Why?  Well it's
    those crooks that are elected into office of course, and the Brain-less
    idiots, they have for Vice-Presidents (sorry Quale, get a Brain!!).

    Ok, so what happened, someone a Hughes goes to NASA, and says "we have a
    problem".  NASA goes to Washington and says "Hughes has a problem".
    The President says "No they don't, get them in here". "Ok, Hughes", says
    the President "Look, we will do like every other time, you be the good
    guys, we'll be the bad quys, and after its all over we will take what
    we can from those cement heads out there".  "Now remember" Says the
    President "latter, after the cement heads forget about all this, give
    them a week, i'll make sure you get some good contracts to hold you
    over".

    Now thats American Policy in Action.  yep, i am cynical today.


                                        William Dee Rieken
                                        Researcher, Computer Visualization
                                        Faculty of Science and Technology
                                        Ryukoku University
                                        Seta, Otsu 520-21,
                                        Japan

                                        Tel: [phone](direct)
                                        Fax: [phone]
                                        [e-mail]

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

Date: 10 Apr 91 06:50:23 GMT
From: unisoft!fai!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re:  Launch Technology:

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

>The most amusing part, actually, is the juxtaposition of Nick's "I know
>what has potential and what doesn't, and chemical rockets don't, so no
>further work should be done on them" [with my J. Paul Getty quote]

Good grief.  Do you really need to see the world in such black and white?

Look, here is a summary: given a suite of launch R&D choices, we
need to choose those with the largest potential improvements.  The potential
improvement of chem rockets ranks well below that of several other
technologies, including laser launch, gas gun, EML, and tether assist.
Currently, over 90% of our launch R&D funding goes to a single technology,
chem rockets, and less than 10% to the other choices.  This is an incredible
misallocation of government R&D funds.  This needs to be rebalanced, so
that the each of these technologies get a sufficient amount of R&D (about
10-20% each, including chem rocket), while another large chunk is given to
the nearly 50 other launch technologies that have been proposed.  The
effort should go towards basic science that applies across several
of the technologies and towards developing working prototypes.  Only the
most promising of the technologies passing these stages will be
kept, and initial operations developed and transferred to industry.

Meanwhile, private R&D can make the incremental and paradigm improvements
in chemical rockets that they are best suited to make, while advising
government R&D towards the most promising problems and markets for the
new technologies.

If that strategy doesn't agreee with my .signature, I don't know what does.


--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 10 Apr 91 14:07:01 GMT
From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: Re: Laser launchers

to: [e-mail] (Ian Stirling)

>>Chem rockets cannot provide even a one order of magnitude drop, but
>>tethers combined with suborbital airplane or laser launch, combined
 IS>                                               ^^^^^
 IS>                                              what is a laser
 IS> launcher? I have heard some references to it,Is it using a
 IS> ground based laser to heat fuel on-board a vehicle so that the
 IS> fuel boils violently,propelling the vehicle.Is this a current
 IS> technology or does it still need massive advances in laser
 IS> technology?

Yes, usually the propellant is water.  Of course the major problem
with the laser launcher is that the technologies for lasers of the
power required and for the guidance systems are VERY highly classified
(between SDI and the various other high-energy laser projects).  It
will be some time before we can pry it loose for commercial use.

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

Date: 13 Apr 91 21:42:39 GMT
From: usc!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: spacesuits (Was: Re: HST in-orbit Maintenance)

Actually, you end up sweating _less_ because of the greater
cooling effect of perspiring into a low-moisture vacuum rather
than high-moisture air. During the recent crisis, people were
giving a figure of water needed per day to prevent dehydration
that is a small fraction of what it takes down here in the high
hunidity of S. La. to keep cool.

--
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: 10 Apr 91 13:35:58 GMT
From: agate!pasteur!dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: new photovoltaic cell

Item of misc. interest:
(From EE Times, April 8, 1991, p76, by Brian Santo)
  "New solar-cell technology developed by Texas Instruments promises to
slash photovoltaic enery costs in half....
  TI's Spheral Solar cell is created with what is billed as an extremely
simple and low-tech process, in which approximately 17,000 spheres of low-
purity metallurgical-grade silicon are bonded to a 100x100 mm square
of aluminum foil.
  While the spheres are being created, impurities in the silicon are
pushed to the surface....Sphere formation is done in a furnace and
depends on a surface tension phenomenon.  Impurities are etched from the
surface of each sphere.
  An aluminum sheet is embossed and etched...and the spheres are bonded
to it with a metallurgical heat/pressure bond.  An insulator is applied
and another sheet of aluminum, so that each sphere becomes a p-n junction
between the two metal layers."
  "Spheral Solar cell prototypes are fully functional, and TI expects that
once in production, the cells will have conversion efficiencies of 8 to 10
percent...."

TI expects to have the cells in production by 1995.  Note: I wonder if those
spheres wouldn't be easier to produce in a zero-G factory?

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

Date: 10 Apr 91 05:55:26 GMT
From: unisoft!fai!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Magellan achieves primary mission objective early (Forwarded)

In article <[e-mail]> [e-mail] (Peter E. Yee) writes:

>    Project Manager Tony Spear said because of the quality of
>the radar images and the excitement they have generated in the
>scientific community, an extended mission for a second 243-day
>mapping cycle has been approved by NASA and will begin May 16.

Good move, NASA!  And congratulations to the Magellan team!


>[Gravity experiments] will provide insight into the interior processes
>of the planet.

This is a fascinating experiment.  An astounding fact is that nobody knows
for sure what causes Earth's magnetic fields (see the recent discussion
in sci.geo.geology).  By studying the differences between the internal
structures Venus and Earth, way may be able to determine why Venus
practically lacks such a field, while the seemingly similar Earth has
a strong field.  Using this information, we can deduce cause of Earth's
magnetic field.


>    Finally, near the end of the Magellan mission, the
>spacecraft may be dipped into the upper atmosphere of Venus to
>drag it into a circular orbit, a previously untried process
>called aerobraking.

Actually, Apollo used aerobraking on its return trip, albeit a quite
different variety combined with reentry.   The Magellan aerobraking
is quite interesting, doing (very slow, I hope!) aerobraking at the
top whisp of the atmosphere with a machine not even close to being
designed for it.

Magellan would be proud.




--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 13 Apr 91 21:11:43 GMT
From: att!news.cs.indiana.edu!ariel.unm.edu!triton.unm.edu![e-mail]  (John Prentice)
Subject: Re: Underground Nuclear Test in Nevada

In article <[e-mail]> [e-mail] (Paul Blase) writes:
>to: [e-mail] (MURTY  Hema Sandhyarani)
>
>
> M >         Yesterday there was another underground nuclear test in
> M >         Nevada.  Why are we allowing this to continue?
>
>Where would you rather that we test them?  Unless you've figured out
>a reasonable worldwide nuclear disarmament program (to include the
>Isreali's, China, India, and everyone else that can make the things)
>we've got to test what we deploy.  I should point out that one reason
>for the testing is to verify new technologies that actually make the
>things safer (less likely to go off in the case of an accident).
>

Though to be fair, we don't target Israel, India, and I kind of doubt
China.  We target the Soviet Union because they pose the only real
threat to us in terms of a serious nuclear (or any other kind) of war.
So I don't think that there is a meaningful linkage between our testing
and nuclear disarmament of any but the Soviets and maybe the Chinese.
As for testing to make these devices safer, the safety issues have to
do with the non-nuclear components of these systems, not the nuclear
portions.  The main reasons for testing are to test the stockpile,
do radiation hardening and effects tests, and to develop new offensive
and defensive systems.  For the very few new nuclear warheads that
have been designed in recent years, there is also some developmental
testing, but this not a big part of the program anymore.

I do think there is a good case to me made that with the rapid easing
of tensions between the U.S.S.R. and the U.S., the need for nuclear
testing is rapidly diminishing.  But that is something best argued
in another newsgroup (sci.military or one of the politics groups maybe).
I would be glad to discuss this point if someone would care to nominate
an appropiate newsgroup to do it in (post your nomination so anyone
else interested knows where to go).

John

--
John K. Prentice    [e-mail] (Internet)
Dept. of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA
Computational Physics Group, Amparo Corporation, Albuquerque, NM, USA

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

Date: 10 Apr 91 07:05:05 GMT
From: unisoft!fai!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: SPACE Digest V13 #364

In article <[e-mail]> [e-mail] writes:
>
>[SETI wants] Intelligent life, not the gas-bags, hawky-
>like creatures or microbes that are thought could be in Jove's atmosphere.

If life exists on Jupiter, the ecosystem would be far larger than Earth's,
giving more mutations a chance to happen, thus a much higher probability
than Earth of evolving intelligent life.  Of course, since we are only
one data point who knows what our chances really were.  :-)  But I would
certainly not discount the possibility of intelligent life on Jupiter,
given a chance of life in the first place.

Now, _technologically active_ life can nearly be discounted, both on
Jupiter and in the rest of our galaxy,  since their remains, if not their
actual presence, would be all over the galaxy including our own
planet.  Semi-technological but highly mathematical creatures, perhaps
like those in Dr. Robert Forward's _Flight of the Dragonfly_, might
still exist.



--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 14 Apr 91 03:49:40 GMT
From: prism![e-mail]  (Matthew DeLuca)
Subject: Re: Space Stations, Money, Startrek

In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>>Okay, I should be a little more accurate here.  You will make no contributions
>>to knowledge if all you do is copy from your neighbor.

>And by the same token, we will make little contribution by merely repeating
>what our neighbor has already done.

Don't forget, though, that Freedom was at least initially going to be
a steap ahead of Mir; it was going to involve signifigant on-orbit assembly
of complex structures, knowledge that would be useful in a number of
applications.  The redesigns, of course, have made it so that there will
barely be more assembly than Mir.  Oh, well.

--
Matthew DeLuca
Georgia Institute of Technology      "I'd hire the Dorsai, if I knew their
Office of Information Technology      P.O. box."  - Zebadiah Carter,
Internet: [e-mail]    _The Number of the Beast_

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

Date: 11 Apr 91 04:27:10 GMT
From: unisoft!fai!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Space Stations, Money, Startrek

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>Okay, I should be a little more accurate here.  You will make no contributions
>to knowledge if all you do is copy from your neighbor.

And by the same token, we will make little contribution by merely repeating
what our neighbor has already done.


--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 10 Apr 91 13:48:06 GMT
From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: Re: More cost/lb. follies

to: [e-mail] (Thomas G Edwards)

 TG> Anyone remember SeaDragon?  A large low-tech booster which would
 TG> launch from sea after being inverted by a water-ballast
 TG> section.  It used decidedly non-delicate, low-tech parts so that
 TG> re-usable stages could be recovered from high altitudes
 TG> requiring a minimal amount of on-board recovery apperatus.


The navy is still working on it too, or at least an up-to-date version.
Saw a display on it at Space-Expo '91 here in DC.


--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

End of SPACE Digest V13 #404
*******************