Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_262.TXT

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Date: Fri, 8 Jul 88 03:23:08 PDT
From: Ted Anderson <[e-mail]>
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Subject: SPACE Digest V8 #262

SPACE Digest                                      Volume 8 : Issue 262

Today's Topics:
         Re: Ruskies find Heaven to the left of Pluto
 passive vs. active support (was Re: Some more launch loop stuff...)
               Re: Space suits
               Re: Space suits
         Re: The launch loop author replies:
         Re: Ruskies find Heaven to the left of Pluto
               Re: Space Suits
             Re: that Canadian guy again
               Recycling Pershing-II's
----------------------------------------------------------------------

Date: 31 May 88 23:53:13 GMT
From: [e-mail]  (RAMontante)
Subject: Re: Ruskies find Heaven to the left of Pluto

[e-mail] (Ken Trant) writes:

,[e-mail] (Eric Behr) says:
,% Yeah, yeah, we want more, we are all bored to death with those silly,
,% uninformative, beside-the-point, endless summaries that Henry Spencer
,% somehow finds time to pound into his keyboard ...............
,%                                                        Eric

Was I out-of-step again by assuming that this was sarcastic and
tongue-in-cheek?
,
, Maybe your bored, But who cares?, keep it up Henry!.
        ^^^^
What about my bored? :-)

Yes, Henry, please keep up the summaries, the synopses, even the opinions.
Otherwise...
    HELP ME!!!
    I'm a poor college student, just finished my M.S., workin' on
    Piling it Higher and Deeper, etc., and *I DON'T HAVE ENOUGH MONEY
    FOR MY OWN AW&ST SUBSCRIPTION!!  So won't you please help?  Send...
(You get th' idea.)

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

Date: 31 May 88 21:30:22 GMT
From: silver![e-mail]  (Lucius Chiaraviglio)
Subject: passive vs. active support (was Re: Some more launch loop stuff...)

In article <[e-mail]> [e-mail] (John Gregor) writes:
>Active systems fail.  That's a fact of life.  Airplanes use a much
>more active support system than trains.  They also fail in many more
>and spectacular ways.  We use them, however, because they are more
>cost effective.  The shuttle and NASP aren't exactly the most passive
>systems around either.

    Actually, trains are more cost-effective than planes when all other
things are equal.  One reason that planes are used more than trains today in
the U. S. is that all other things are NOT equal -- the government supports
the infrastructure needed for air travel MUCH MORE than it supports the rail
infrastructure -- otherwise we would most likely still have an extensive and
decent-quality rail network and only limited air travel -- something like what
one sees in European countries.  In fact, if we are to cope with upcoming
energy shortages, pollution problems, safety problems, and other problems, we
are going to have to move in that direction, but that's a subject for a whole
different newsgroup.  The other reason people use planes instead of trains is
that many people are willing to pay more to go faster.

    Now, for getting into space, it doesn't look like passive structures
are going to cut it -- the cost of a passive structure is going to rise at
least with the fourth power of its height, all other things being equal (which
they aren't), because merely increasing all linear dimensions gives you a
structure that is proportionately weaker in comparison to its weight.  I don't
know how actively-supported self-propelled vehicle cost scales up with how
high it has to go but I'm pretty sure it isn't as bad as the fourth power of
the height.

>>You can support an accelerator (linear motor, mass
>>driver, whatever) from a series of towers of increasing
>>height with suspension bridges strung between the
>>towers.  If the power goes down, your structure does not
>>fall out of the sky.
>>
>>Using towers also allows for incremental construction.
>
>Again, is this within the capability of today's materials?  Any references?

    I see no reason why the support structures for a linear accelerator
wouldn't be within the capability of today's materials -- particularly if you
use mountains as part of your support structure.  This kind of hybrid
approach, where passive support is used part of the way (in the part before
the cost gets scaled to the point of unfavorability), followed by ballistic
and/or powered flight, is something that should be considered.  However, I
don't have a clue as to whether that or self-powered hyperspeed air-breathing
vehicles (like the National Aerospace Plane but without the myriad foulups
that the NASA and the rest of the government are sure to put into it) would be
more cost-effective.  Perhaps the best approach would be the following kind of
hybrid:  low-end linear accelerator gets air-breathing vehicle up to the speed
at which scramjets become reasonably efficient, then air-breathing vehicle
uses its scramjets to get out of the atmosphere at suborbital speed (it has
been said that scramjets start to have trouble at speeds over Mach 20, so Mach
20 is suggested); finally, rocket-powered vehicle piggybacked on air-breathing
vehicle gets into orbit while air-breathing vehicle re-enters (since it's not
quite up to orbital speed) and lands for turnaround.

    Oh well -- if I can think of any way to get to the stars by train,
I'll for sure let you know. . . .

    -- Lucius Chiaraviglio
       [e-mail]
       [e-mail]    (in case the first one doesn't work)
    Maybe your next spaceflight should be on a train.
    STARTRAK

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

Date: 30 May 88 13:55:59 GMT
From: mcvax!ukc!its63b![e-mail]  (ERCF08 Bob Gray)
Subject: Re: Space suits

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>However, note that neither existing manned spacecraft nor existing spacesuits
>are contamination-free; far from it.  I doubt that the space activity suit
>would be spectacularly worse.

Even if the activity suit is outgassing all sorts of
contaminants, the solution would be as simple as puting on a
thin sealed plastic isolation suit like on earth. It doesn't
need to hold any pressure, just channel escaping gas away.
    Bob.

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

Date: 30 May 88 14:51:52 GMT
From: mcvax!ukc!its63b![e-mail]  (ERCF08 Bob Gray)
Subject: Re: Space suits

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>
>...NASA
>displays no interest in pursuing the scheme further, even though it funded
>the original work and nobody has found any real flaws.  If one were being
>cynical, one might suspect an overly-cozy relationship between NASA and its
>current space-suit suppliers; it wouldn't be the first time.

And in article: <[e-mail]> [e-mail] (Mike Van Pelt) writes:
>Sounds bogus to me.  ....
>....  Probably (1) NIH  and (2) not expensive enough.

One idea which occured to me is that, how can I put this,
the the skin of the female body is much easier to support
and pressurise than that of the male.

A large patch of strategically placed sticky tape, or
its high-tech equivalent, would be enough to prevent
escape of gas and liquids from the lower body openings, and
to protect the more delicate tissues there.

Support to pressurise the skin of male body would be more
difficult to devise, and would be extremely uncomfortable to wear.

The advantage would then be in employing female astronauts
for all EVA work.

Or am I overestimating the amount of support the more
delicate skin tissues need?

And also, has any thought been given to using this suit
design for the lightweight suits needed on Mars if and when
expeditions go there?
    Bob.

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

Date: 1 Jun 88 01:22:39 GMT
From: [e-mail]  (Paul F. Dietz)
Subject: Re: The launch loop author replies:

In article <[e-mail]> [e-mail] (Keith Lofstrom) writes:
>2)  Loop technology is useful for other things, and this provides a growth
>path for the technology.  Underground power storage and transmission may be
>possible (this depends on real world small-bore rock tunneling costs, an
>unknown).
...
>6)  "Okay, smarty pants, if it's so simple, why aren't you building one?"
>Well, first, I'm lazy.  I wrote the "Analog" article to drum up interest.
>I mailed out around 200 copies of the paper, and wrote hundreds of personal
>letters.  I was hoping someone would steal the ball and run with it. Nuh-uh.

What about those fellows at Argonne?  Directly inspired by Keith's
launch loop proposal -- they even cite the Analog article -- they noticed
magnetically confined flywheels have excellent scaling properties
(energy stored per unit system mass scales linearly with radius).  They
have published several papers on their concepts (see, for example,
"Magnetically Confined Kinetic-Energy Storage Ring Using Attractive
Levitation", J. R. Hull et. al., IEEE Trans. on Energy Conversion,
Vol. EC-2, No. 4, Dec. 1987, pp. 586-591).  They have a neat scheme for
making attractive levitation passively stable using the strong
focusing principle -- a spinoff of particle accelerator research
-- that might be useful in the 180 degree bending sections of
a launch loop.

> "Simple" towers built around 2Km/sec ribbons can poke above
> the atmosphere, and are useful for scientific observations...

I still like the idea of levitating a superconducting cable using
j x B forces, B the geomagnetic field, possibly augmented with
ground cables running in the opposite direction.  It's passively
stable, although it does fall if the circuit breaks.  You need
pretty fierce current densities for this to work, though.

    Paul F. Dietz
    [e-mail]

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

Date: 1 Jun 88 03:30:39 GMT
From: sonia![e-mail]  (Eric Behr)
Subject: Re: Ruskies find Heaven to the left of Pluto

In article <[e-mail]> [e-mail] (RAMontante) writes:
 >[e-mail] (Ken Trant) writes:
 >,[e-mail] (Yours sincerely) says:
 >,% Yeah, yeah, we want more, we are all bored to death with those silly,
 >,% uninformative, beside-the-point, endless summaries that Henry Spencer
 >(etc.)
 >Was I out-of-step again by assuming that this was sarcastic and
 >tongue-in-cheek?
No, you weren't - but did you have to say this? I was beginning to have
a real ball...
                                                       Eric

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

Date: Tue, 31 May 88 10:41 EDT
From: [e-mail]
Subject: Re: Space Suits

    The best concept I have seen for a rigid space suit has already
    been built in prototype form - for the movie 2001.   The problem
    of staying still without using gross amounts of fuel would remain,
    but I would try to address that in the basic design of a space
    station.  The first thing to build should be a tiny monorail
    track (a single aluminum I beam).  Two more attached parallel
    tracks would give the beam structural stability and serve
    as permanent mounting beams for modules.  (Solar wings, gas/fuel
    tanks, antenae etc.)  There would be a single construction/repair
    site and an automated system for moving packages between attachment
    points and the construction site.  Since movement and attachment
    is along rails it falls within the capacity of current robot
    technology.  (Everything is rigid so the motions can be
    precisely described/programmed ahead of time.)  Furthermore,
    the whole structure can be extended by making the rails longer.

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

Date: 31 May 88 17:00:25 GMT
From: pacbell!att!alberta!mnetor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: that Canadian guy again

> I bet he's a Space Alien -- does anybody know if his socks match?

You lose -- it's summer (well, effectively so, in Toronto at least) and I've
switched to sandals, so it's been weeks since I last wore socks!
--
"For perfect safety... sit on a fence|  Henry Spencer @ U of Toronto Zoology
and watch the birds." --Wilbur Wright| {ihnp4,decvax,uunet!mnetor}!utzoo!henry

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

Subject: Recycling Pershing-II's
Date: Wed, 01 Jun 88 09:49:17 -0400
From: Fred Baube <[e-mail]>


[Moderator - Please feel free to abridge this]

Today's (Wed 1 June) Washington Post describes how they will not
go to a complete waste.  Article by R. Jeffrey Smith, WP Staff
Writer, excerpted without permission.

There is a photo captioned, "A technician practices sawing up a
US ground-launched cruise missile that has been drained of jet
engine fuel."

Further:
"Each side will attempt to reclaim a portion of its hefty
investment in the weapons by reusing missile components and
associated equipment that are excluded from the INF constraints.
The Soviets, for example, will modify nearly 1000 missile-
launching vehicles under US inspection and use them to transport
timber or large pipes, at an estimated savings equivalent to $73
million.

[The Soviets will also reclaim precious metals] from missile
guidance systems, and extract plutonium from warheads for use in
civilian reactors.

Arms negotiator Alexei Obukhov claimed that 'electronic instru-
mentation' from the missiles would be used in 'radio engineering
or television'.  These efforts will not be subject to US
monitoring.

The US Army will retain several hundred truck cabs .. plus
associated radios, generators and tool kits.  76 cruise missile
launch control centers, worth $6 million each, will be modified
for re-use in unspecified Air Force programs.

Another $114 million worth of cruise missile motors and guidance
sytems will be given to the Navy for installation in nuclear-
tipped SLCM's .. Studies are underway on re-using the nuclear
warheads in new US ALCM's and SLCM's that fall just outside the
INF constraints.

Although the theaty is widely said to be the first to eliminate
an entire category of nuclear missiles, it allows each side to
retain 15 missiles and launchers, to be irreversibly modified for
harmless public display as a memorial to one of the most novel
arms treaties ever achieved."

Another story, also by the same writer, describes the atmosphere
at the Hercules, Inc. plant west of Salt Lake City, where Soviet
inspectors will be stationed for the next 13 years.

"'Russians are coming, Russians are coming' screamed a recent
headline in the company magazine ..

Company officials are concerned that the Soviets .. will purloin
company secrets .. and that the Pentagon will think twice about
placing new orders at a plant where the Soviets can inspect much
of what comes and goes thru the main gate.

Their fears have been assuaged only partly by written orders from
[Carlucci and others] barring such discrimination, and by an NSA
pledge to make the company's internal communications network
resistant to electronic eavesdropping."

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

End of SPACE Digest V8 #262
*******************