Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_6/V13_607.TXT

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Subject: SPACE Digest V13 #607

SPACE Digest                                     Volume 13 : Issue 607

Today's Topics:
           Re: Rational next station design process
           Moonbase movie *Plymouth* to air Sunday?
             Re: Gravity vs. Mass
             Re: Building Infrastructure
Re: Stepping back, asking why? (was Re: Rational next station design...)
      Re: Fred vs. Exploration: head-to-head competition
             Re: Gravity vs. Mass
           Re: Rational next station design process
             Re: Gravity vs. Mass
           Re: Rational next station design process
    Re: Revising a biased history of space science funding

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
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----------------------------------------------------------------------

Date: 23 May 91 06:00:54 GMT
From: agate!earthquake.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Rational next station design process

In article <[e-mail]> [e-mail] (George William Herbert) writes:
>Here are the missions that I want to see done that I think can be done only
>or best by a station:
>    * Long-term Human studies
>    * some Microgravity (not all)
>    * most Biological science
>    * Spacecraft Refurbishment
>
>Assume, as I do, that these are worthwhile things to do.  (Not more or less
>worthwhile than any other mission).  If you disagree, then we stop here.  If
>not, proceed to step 2:

To satisfy Nick Szabo and others, who think that a station would be a
unproductive waste, let me suggest a step 2.

Step 2: After selecting those missions which can only be done by a space
station, or which are greatly simplified by a station: Make sure that these
missions are compatible. (Spacecraft refurbishment would casue vibrations
which may interfere with microgravity work...) Then calculate the value
of these missions. Based on the value of this work, you can come up with
a budget for the station design. If George Herbert and others have some
cleaver ideas, and a station could be build within this budget, it should
be. If Nick Szabo and others are correct, and to worth of the above missions
is too little to justify the station, it should not be built. In any case
the cost of the station MUST be compaired to the worth of the work it will
do.

Two notes: In order to see if the missions justify the station, SOME design
work MUST be done on the station (or better yet, several station concepts.)
in order to establish the cost of building a station. (Freedom's budget gives
us only the cost of building ONE station concept, under poor a poorly
administrated organization.)
Second, simply considering the worth of the various missions will help the
design: It provides a quick and easy way to set priorities. If the most
valuable work done on the station will be, say, spacecraft refurbishment,
then the designer will know not to waste time and energy on the less
valuable missions. (I am not making a judgement on spacecraft refurbishemnt,
only using it as an example.)

                        Frank Crary
                        UC Berkeley

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

Date:     Thu, 23 May 1991 02:20 CDT
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject:  Moonbase movie *Plymouth* to air Sunday?
Original_To:  SPACE,smtp%"[e-mail]"

Here's a tip.  I just heard a rumor that the made-for-TV movie
*Plymouth* will be broadcast on NBC this coming Sunday.  I don't know
how accurate this rumor is-- but if it's true, catch it!  The director
made a presentation at last year's Space Development Conference,
showing slides of the sets and characters.

*Plymouth* is about a near-future community of a few hundred people on
the Moon.  The filmmakers went to some trouble to tell a hard-science
story with plausible tech.  The director had really boned up. The
people he got as advisors-- such as moonbase maven Dr. Wendell Mendell
of NASA, or space artist Pat Rawlings of Science Applications
International-- were the same people I would have gotten.  I was
amazed to hear this Hollywood guy spout all the same technical jargon
as I'd heard at professional astronautics conferences.  The colony's
main export is helium-3, and it makes extensive use of local lunar
resources.  The designs of equipment, vehicles, and buildings are
quite convincing.  Hard science is almost never done well in
Televisionland, but this movie appears to be an exception.

*Plymouth* was intended to be a pilot for a TV series, but didn't get
picked up by the network.  The quality of the drama is unknown to me.
If it's a mediocre story, like *Destination Moon* or *Die Frau im
Mond*, the movie should be watchable because its technical background
is strong.  (No flames, please; how many SF movies have you sat
through with interesting plots, or intriguing characters, and lousy,
lousy science?)  If the story is good, you might be *really* pleased
you tuned it in.

     O~~*           /_) ' / /   /_/ '  ,   ,  ' ,_  _           \|/
   - ~ -~~~~~~~~~~~/_) / / /   / / / (_) (_) / / / _\~~~~~~~~~~~zap!
 /       \                          (_) (_)                    / | \
 |       |     Bill Higgins   Fermi National Accelerator Laboratory
 \       /     Bitnet:     [e-mail]
   -   -       Internet:  [e-mail]
     ~         SPAN/Hepnet:      43011::HIGGINS

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

Date: 21 May 91 13:11:29 GMT
From: prism!mailer.cc.fsu.edu!geomag![e-mail]  (Joe Cain)
Subject: Re: Gravity vs. Mass

In article <[e-mail]> [e-mail] (Isildur) writes:
>I was having a debate with one of my friends over this one... You somehow
>dug a hole clean through the earth in a diameter through the core and it was
>completely insulated from the heat changes running through the planet.  When
>you climbed into the tunnel (fall into the the tunnel...) and reach the
>center of the planet, would your weight be incredibly multiplied because of
>your new relative location to the center of the earth (using the
>mass/gravitational constant formula) or would you have zero-weight because
>you were surrounded by virtually identical mass (and also assuming that the
>tunnel closes up outside your immediate location)?


You undergo simple harmonic motion in the case of a planet with
constant density, and so long as the mass is spherically symmetric,
zero gravity at the center.

For the real Earth, gravity increases slightly from the crust to the
core-mantle boundary since the core is so much more dense. It then
decreases about linearly to r=0.


Joseph Cain        [e-mail]
[e-mail]        scri::cain

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

Date: 21 May 91 18:13:12 GMT
From: agate!spool.mu.edu!think.com!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Building Infrastructure

In article <[e-mail]> [e-mail] writes:
>>Like the Kelly Act, this approach is intended to create markets.
>
>Not at all.  The Kelly Act was aimed at a _current market_, mail
>delivery...

References, please.  My understanding has always been that there was
no particular market for *air* mail before the Kelly Act.  Customers just
didn't think the faster delivery was worth anything to them.  (They
revised their opinions once it was actually available and dependable.)
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 22 May 91 03:18:36 GMT
From: agate!headcrash.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: Stepping back, asking why? (was Re: Rational next station design...)


    I think I've opened a can of worms 8-)

    In any case, I would like to suggest that we split a bit into two
threads; a discussion of the justifications for wanting or desiring a
manned station (or program, or unmanned for that matter...) and one on
my origional topic of carefully and rationally designing a station.
    I'd still be interested in input on missions for a station.  I have
an intrinsic distrust of things I do totally on my own... 8-)

-george william herbert
[e-mail]

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

Date: 22 May 91 04:34:46 GMT
From: usc!samsung!uakari.primate.wisc.edu!dali.cs.montana.edu!ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Re: Fred vs. Exploration: head-to-head competition

In article <[e-mail]> [e-mail] (Douglas Creel) writes:

>As far as manned space drawing funds away from "space science" projects,
>there certainly was no shortage of unmanned missions to the planets
>during the sixties and early seventies, and that was during the height
>of the Apollo Program.


Let's take a look at the actual facts:

* From the time Sputnik, the unmanned satellite, motivated our
  country into action and radically increased space funding, until
  1966 unmanned lunar and planetary exploration drew about $900 million
  (in $1985) per year.

* From 1966 until 1971, the Apollo program dominated funding, and funding
  for automated exploration dropped to $400 million per year.

* During 1971-1975, Apollo flights were cut short, and planetary
  exploration funding staged a renaissance, to a peak of $900 million in
  1975.

* During 1975-1985, the Shuttle grabbed an increasing share of the funds,
  and planetary exploration dropped to a low of $200 million in 1984.

* Planetary exploration has since barely risen since, to about $300 million
  per year (remember these are all $1985 figures) since the Shuttle
  still dominates costs.

Reference: _Breaking the Bonds of Earth_, Lewis & Lewis, Columbia
University Press 1987.

At each point during history -- the Shuttle being the most dramatic
example, but not the only one -- funds for astronaut projects came
directly at the expense of funds for planetary exploration.  When
astronauts projects have been cut back, space exploration has gained
a large increase in funding.  The most probable scenario, if Fred stays
cut, is for exploration to undergo a renassaince in funding, and for the
NASA budget as a whole to be reinvogorated now that it has gotten rid of a
project almost universally considered wasteful.  Unless NASA's leaders
scotch the trend, we could see _hundreds_ -- 100's -- of new exploration
projects being undertaken in the late 1990's.

Do the arithmetic: $120,000,000,000/100 = $1.2 billion for each
of 100 projects.  In fact, it is better to undertake more than
100 projects for less than $1.2 billion apeice.

More efficient are worthwhile projects include Goddard's SMEX
program extended into deep space, a new generation of small telescope
satellites (eg an infrared telescope dedicated to asteroid and comet
search), an infrared telescope put into a meteor-shower orbit to study
the mass distribution and makeup of comets and their fragments,
several Lunar and Mars orbiters, ground telescope construction and
operation, analysis of asteroid samples fallen to Earth, and a host
of other projects.

Two myths promulgated by the astronaut fans have come crashing
down: (a) that astronauts motivate funding -- this has never
been true, and (b) that NASA can afford to spend money even on
wasteful projects.  Both notions have proven to be political
suicide.  Now the astronaut fans are trying to make up a new myth
-- "Fred money is going to HUD".  But these myths  wear thin
after awhile; it is quite obvious that the Committee funded space
science, NSF and EPA, not HUD, out of this year's Fred money.

BTW, if we are going to fight HUD, proposing to spend money that
can buy 2 million houses to instead buy just one house is, politically
as well as logically, the worst possible way to win that fight.

All in all, the astronaut fans have made up their own little world where
scientists are mere pests, the people who fund their programs are
"bean counters",  the only alternative to their astronauts is HUD,
and they have a God-given right to the largest piece of NASA's pie.

They forgot that scientists provide the knowledge, politicians provide
the money, people still need to live on _this_ planet for a little
while yet, and most voters have more important things to worry about than
the adventures of a few astronauts.  The chickens are coming home to
roost.


--
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: 22 May 91 04:01:51 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Gravity vs. Mass

In article <[e-mail]> [e-mail] writes:
>Question: assume the ends of the hole are open to the atmosphere.
>What's the pressure function of the air in the hole?
>
Is the tunnel isothermal? Or does its temperature vary as the core/mantel
temperature around it? Also, is the tunnel wide enough to allow convective
cells (applies only if the gas is not isothermal) or is the gas stratified?

                   Frank Crary
                   UC Berkeley

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

Date: 22 May 91 04:37:42 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!think.com!sdd.hp.com!uakari.primate.wisc.edu!dali.cs.montana.edu!ogicse!sequent!muncher.sequent.com![e-mail]
Subject: Re: Rational next station design process

In article <[e-mail]> [e-mail] (George William Herbert) writes:

>If you don't feel that such needs are a priority item, feel free to say so,
>but don't criticize an approach to designing a station on those grounds.

It is precisely the approach that is wrong.  I could point out
thousands of needs _not_ met by a space station, and demonstrate
the opportunity costs.  I could show how the needs you are trying
to meet can be better met by other methods.  But if we
don't consider alternative concepts, our only recourse would be to
redefine the needs, as space planners have redefined the space
station customers from defense (1960's) to earth observation
(1970's) to microgravity research (1980's) to "life sciences"
(the study of a too small sample size of unrepresentative humans in
an unrepresentative space environment).  We could argue about these
until we were blue in the face.  But until we consider the
alternatives to a station, and all the major needs of space
users and their relative importance, the notion that a space station
is a desirable or useful part of a space infrastructure is a
non-sequitur.  It is merely the classic Solution in Search of a
Problem.

The whole approach -- and any infrastructure that may result from
it -- is, like Fred itself, bankrupt.



--
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: 22 May 91 15:31:09 GMT
From: swrinde!zaphod.mps.ohio-state.edu!think.com!spool.mu.edu!uwm.edu!csd4.csd.uwm.edu![e-mail]  (Mark William Hopkins)
Subject: Re: Gravity vs. Mass

In article <[e-mail]> [e-mail] (Timothy Banks) writes:
>re: Discussion of Gravity at the Centre of the Earth.
>
>Now for a fun bit: Consider a frictionless straight tunnel right through
>the Earth. and not necessarily through the centre. How long to get to the
>other side?

Without going through any of the calculations, if you assume the Earth is
basically uniformly distributed (it's not ;)) then for very fundamental reasons,
your motion through the tunnel must be an exact projection along the axis
of the tunnel of the corresponding motion *around* the planet in a circular
orbit (if it were possible to orbit at zero altitude).

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

Date: 22 May 91 18:41:46 GMT
From: van-bc!rsoft!mindlink![e-mail]  (Nick Janow)
Subject: Re: Rational next station design process

[e-mail] (George William Herbert) writes:

> No.  I'm doing a specific project with a specific set of missions.  The life
> science/human biology people will use it, as well as a few others 'while
> we're there'.

I'm sorry, but I can't accept your approach.  It sounds like "Let's make a
flashy lab facility (for political purposes).  I'm sure that once it's built we
can find uses for it."  That's the approach that led to the space shuttle.  :(

> The government in its infinite (cough) wisdom already funds similar
> missions/needs, so presumably that's where it will come from.

It sounds like you're again saying, "This is the way they do things, so it must
be okay."

> The Executive branch feels it's 'worth' whatever they think it will cost...

They are paying for it out of their own pockets, nor will they likely see the
final bill in their term of office.  This approach is really scary in a deficit
situation, since it's a case of, "Oh well, we've already got a deficit; what's
a little bit more?"

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

Date: 24 May 91 02:47:39 GMT
From: convex![e-mail]  (Richard A. Schumacher)
Subject: Re: Revising a biased history of space science funding

[e-mail] (Karl Stapelfeldt) writes:
>every year.  It may be a political reality that Fred doesn't have the
>support to be fully funded right now; we'll see what the President
>can do.

Fred clearly has very little scientific support either. Is the
Executive branch meant to be the last refuge for those projects
which have continually failed peer review?

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

End of SPACE Digest V13 #607
*******************