Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_5/V13_571.TXT

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Subject: SPACE Digest V13 #571

SPACE Digest                                     Volume 13 : Issue 571

Today's Topics:
          Re: SPACE STATION FREEDOM WOUNDED
               Re: Saturn V and the ALS
               Re: Saturn V and the ALS
              Re: Why the space station?
             Re: LIGO (was Re: IT'S OVER)
            SPACE Digest V13 #560
               Re: Saturn V and the ALS
          Re: SPACE STATION FREEDOM WOUNDED
          Re: SPACE STATION FREEDOM WOUNDED
        Re: Hypersonics ... paritcularly Hotol
             Re: Space Station Cancelled

Administrivia:

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

Date: 16 May 91 13:58:19 GMT
From: agate!bionet!uwm.edu!ux1.cso.uiuc.edu![e-mail]  (Doug McDonald)
Subject: Re: SPACE STATION FREEDOM WOUNDED


In article <[e-mail]> [e-mail] (Fraering Philip) writes:
>In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>
>>Sigh, the politics of envy...  They're dreaming if they think it will have
>>more than a momentary effect on their own financial problems.
>
>What do you expect? In all government-dominated fields everything
>seems to degenerate into a zero-sum game.
>
>--

That is MOST EMPHATICALLY not true: the pie is getting bigger every day.
Quite a bit bigger. And, of course, one program gets all of the increase
and then some, quite a bit more in fact. The part that gets more is called
welfare.

Doug McDonald

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

Date: 17 May 91 01:55:54 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Fraering Philip) writes:
>What's pretty odd is, the synthesis group is calling for a booster
>made up of Saturn engines mated to shuttle external tanks (which
>the historians present will recognize as similar to Jarvis); I
>guess projects are only worthwhile if totally controlled by you-know
>-who.
>
No, I don't know who. Are you trying to say that OSC or Amroc is in some
mysterious way controlled by NASA or some other government agency?

                   Frank Crary
                   UC Berkeley

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

Date: 17 May 91 02:08:39 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (S. J. Okay) writes:
>Speaking of which, whats wrong with using this as a crew transport vehicle?
>If we're going to revive the Saturn V and spend all those $$$ on retooling,
>why not spend an extra few to revive the Apollo CM?.
>
An Apollo CSM would be a poor choice for a crew transport. It masses 22
tonnes and carries 3 people to orbit. It was designed to provide the
3 man crew with about a week of life support, and far more manuvering
capability (e.g. fuel) than an orbital transport. If I may invent a
figure of merit, the Apollo CSM masses over 7 tonnes/ man-to-orbit.
The soviet Soyuz (a equally old design) masses 2.3 tonnes/ mann-to-orbit.
>BTW, were Fred to ever have a lifeboat capability, why not use the CM capsule?
>If I recall correctly, there was some extra space in the capsule itself that
>might provide room for the 4th seat.
>
In fact, a Assured Crew Return Vehicle (e.g. a lifeboat) is part of the
Freedom budget. (If such a thing still exists). The ACRV would be a better
choice for a crew transport. Most of the designs run around 1-2 tonnes/
man-from-orbit. (e.g. around 7 to 20 tonnes and 4 or 8 man crew.) If the
ACRV were launched with people on board, it would make an adaquate crew
transport.

                                         Frank Crary
                     UC Berkeley

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

Date: 16 May 91 08:38:22 GMT
From: ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Re: Why the space station?

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

>>[I write]
>>There is no
>>benefit from assembly...

>Except that the mission is too big for existing boosters.
>...And especially if you remember that
>you're never going to get funding to fly more than one of these

Correction, we're not going to get funding to fly more than _zero_
of these.  Which is the answer to your objection.

Nor should we.  I don't know any explorer worth his or her salt
that advocates spending $tens of billions for one mission at the
expensive of several dozen other missions, such as orbital telescopes,
flyby probes, lunar and planetary orbiters, comet rendesvous, etc.

Heck, the Mars Observer just got barely funded.

Justifying one $tens of billion waste in terms of an even larger waste
of $tens of billions.  More silliness from an idea in its death-throws.



--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 16 May 91 11:04:46 GMT
From: mcsun!ukc!edcastle!hwcs![e-mail]  (Stewart Fleming)
Subject: Re: LIGO (was Re: IT'S OVER)

In article <[e-mail]>,
[e-mail] writes:

>One thought that occured to me is that since there is no natural "resonance"
>to a LIGO arm, that a laser beam 6 million miles long will be no more
>efficient that a laser arm 1 mile long if the gravity waves being detected
>are only a few meters in length. I throught that a better design would entail
>the laser beams re-intersecting the SAME region of space/time multiple times
>to increase the apprent effect.

From my notes of a recent lecture given by two leading researchers into
gravity research (which I posted to sci.astro and sci.physics a while back
and promptly lost) :

Dr Norna Robertson and Jennifer Logan - Dept. of Physics and Astronomy,
University of Glasgow.
"The Search for Gravitational Waves"
Lecture given at the Edinburgh International Science Festival, April 1991.

...sensitivity limits of detectors [laser interferometry, as above] are set
by things like thermal energy, ground vibration, gas molecules hitting the
end masses and the available light power.  The effect of these decreases as
the length of the arms of the detector increases.

It is necessary to "amplify" the light signal output from the laser
interferometer : this is a measure of the displacement of the end masses and
hence of the amplitude of any gravitational waves detected.  Two mechanisms are
used :  delay lines, where the beams overlap and Fabry-Perot cavities where the
beams lie on top of one another.  [This is the idea expressed above : laser
beams intersecting the same region of space/time multiple times.]

With apologies to any gravitational wave researchers out there for any
inaccuracies : this really isn't my field.

>Mike

STF
--
[e-mail]                        ...ukc!cs.hw.ac.uk!sfleming
"Wow ! A flying mouse !"  "Eeek ! A flying cat !"

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

ReSent-Message-ID: <[e-mail]>
Resent-Date:  Thu, 16 May 91 18:06:47 EDT
Resent-From: Tom McWilliams <[e-mail]>
Resent-To: [e-mail]
Date:         Thu, 16 May 91 02:53:25 EDT
Reply-To: [e-mail]
From: [e-mail]
Subject:      SPACE Digest V13 #560
Comments: To: [e-mail]
To: david polito <[e-mail]>, Tom McWilliams <[e-mail]>

Re: Solar Collectors;

>If you are doing things with solar power on a large scale, doing it near
>Mercury is probably better than doing it near Earth.

Sure, set up operations in near Mercury.  How am I supposed to refine anything
if you're shadowing my sun?  You inners always dump on us belters! :-b

Tommy Mac
Acknowledge-To: <18084TM@MSU>

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

Date: 17 May 91 04:42:42 GMT
From: spool.mu.edu!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Frank Crary) writes:

>This may not be a "short term sacrifice" The ESA and Japan treat the inter-
>national agreement to develop and operate Freedom as an legal treaty with
>another nation, and that it is a binding international law. Of all the
>nations contributing to Freedom, only the US feels that they can freely
>change the design (or trash it) whenever they please. If we do dump
>Freedom (as opposed to orbiting something that still meets our agreement
>with ESA/NASDA/etc...) then we may NEVER be able to enter into another
>jont venture with anyone. By dumping Freedom, we FORCE these parties to
>"squander billions" themselves, without even warning them...

So then we are bound by treaty to build Freedom, no matter what the
cost? All the Japanese would have to do would be to hold us to that,
and we'd have to build Freedom, which would be useless for U.S. mic-
rogravity business, and which would use up most of the trained people
in building that sort of thing, and not to mention billions and billions
in venture capital.... What a way to keep the U.S. commercial space
effort crippled while beating the pants off them in zero-g processing!
Tie Freedom around their neck like an albatross!

Seriously, both the Europeans and the Japanese would probably like
it a lot if we stopped pretending we could do the job with the
current shuttle/station configuration, came up with a much better
shuttle, built a station with that, and used _that_ station to
fufill the treaty obligations...

Because the way Freedom is going even without the cancellations,
we won't be able to fufill the obligations, and it will cost
$ 40 billion _anyway._


--
Phil Fraering || Usenet (?):[e-mail] || YellNet: 318/365-5418
''It hardly mattered now; it was, in fact, a fine and enviable
madness, this delusion that all questions have answers, and nothing is
beyond the reach of a strong left arm.`` - Larry Niven and Jerry
Pournelle, _The Mote in God's Eye_

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

Date: 17 May 91 01:52:34 GMT
From: mintaka!olivea!samsung!usc!jarthur!nntp-server.caltech.edu![e-mail]  (Steinn Sigurdsson)
Subject: Re: SPACE STATION FREEDOM WOUNDED

In article <[e-mail]>, minsky@media-lab (Marvin Minsky) writes:
>In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>
>>The next step however, is to turn this into an advantage. If Freedom
>>is killed we need to push for a real station. This would be a good time
>>to tell your Congresscritters about projects like the Commercially
>>Developed Space Facility or ideas from the SSI External Tank Study.
>>Push to get them funded.
>>
>
>The next step however should be to think again.  Several small
>remotely manned space stations would develop the technology for a
>more plausible manned one later.  Repeating Skylab makes little sense;
>telepresence in the natural next step.  It could produce so many
>wonders in LEO, GEO and on the moon that the public will DEMAND larger
>manned projects soon.  But if the reduced Fred were to proceed, the
>public will only quit a little later, setting everything back even
>more.  C'mon guys, you're all living in 1970.

    I am curious about this. Does anyone know just how much
bandwidth is needed to run a half-useful space station remotely?
It seems to me that the current data transfers are fully occupying
TDRSS, and a new ground station network is very unlikely.
    So, either you need semi-autonomous stations with (very) good AI
to run things locally (and space certified hardware for the space
certified, debugged AI software!!!), or you need a _very_ large capacity
relay network, at no inconsiderable expense.

    Does anyone have hard numbers on this?

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

Date: 16 May 91 09:04:53 GMT
From: ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Re: SPACE STATION FREEDOM WOUNDED

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>...  They're dreaming if they think it will have
>more than a momentary effect on their own financial problems.

Even a _momentary_ effect is enough to pay for SIRTF, AXAF,
a greatly expanded ground-based visual search, a greatly expanded
Antartic asteroid sample return mission, _and_ a gaggle
of small infrared probes launched into the meteor showers.

That's right, _all_ of that, spread over several years, costs just
one year of peak Fred funding (c. $10 billion by GAO estimates).

In addition, once these are payed for -- especially the smaller
quicker missions, like the visual search and Antartic manned mission
-- politicians will leap at the chance to do space programs that
produce results within their term of office.

If this hold up, this is a GREAT moment for space exploration.


--
Nick Szabo                [e-mail]
"If you understand something the first time you see it, you probably
knew it already.  The more bewildered you are, the more successful
the mission was." -- Ed Stone, Voyager space explorer

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

Date: 15 May 91 13:27:19 GMT
From: eru!hagbard!sunic!mcsun!ukc!inmos!penguin![e-mail]  (Paul Sidnell)
Subject: Re: Hypersonics ... paritcularly Hotol

The last I heard (< 6 months a go, here on the net) was that some strange
deal with the Soviets was in the offing, which involved some cut down version
of Hotol with a "conventional" first stage (whatever that is).

I was under the impression the the British government had (at least partial)
rights to the engine since it supplied some of the funding, and so blocked
BA from seeking private partners, killing it dead.

I too am interested in this project if only to add to my morbid collection
"Good projects my government has killed/sold/ignored" scrapbook.

Can anyone add facts to my recollections of third-hand hearsay ?

 ...___...  ...___...  ...___...  ...___...  ...___...          Iceberg ?
Paul Sidnell, Software Group,      | Phone [phone]     |  What iceberg ?
INMOS Ltd. 1000 Aztec West,        | UK: [e-mail] |      ....
Almondsbury, Bristol, BS12 4SQ, UK | US: [e-mail]   | Oh, THAT iceberg.

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

Date: 16 May 91 07:44:03 GMT
From: unmvax!ddnvx1.afwl.af.mil!sun4b![e-mail]  (Reg Clemens)
Subject: Re: Space Station Cancelled

In article <[e-mail]> [e-mail] (Jim Bowery) writes:
>The VA, HUD and Independent Agencies Subcommittee of the House
>Appropriations Committee canceled Space Station Freedom at around
>the end of business (4pm or so) today (5/15/91).
>-----------------------------------------------------------------------------
>Jim Bowery      619/295-3164               The Coalition for
>PO Box 1981                                   Science and
>La Jolla, CA 92038                             Commerce
>-----------------------------------------------------------------------------


Lets hope they have the courage to keep it cancled.. Then we can get
on with doing some REAL Space Science.
--

                Reg.Clemens
                [e-mail]

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

End of SPACE Digest V13 #571
*******************