Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_2/V11_217.TXT

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Subject: SPACE Digest V11 #217

SPACE Digest                                     Volume 11 : Issue 217

Today's Topics:
               Re: Velikovsky's Theory
          Re: Will we lose another orbiter?
              Re: Saturn V gone forever?
       Re: HST orbit (was Re: Comparative Costs to LEO)
      Re: What does it cost to push a pound into orbit?
               Re: Velikovsky's Theory
           Smithsonian Air and Space Museum
          Re: Will we lose another orbiter?
               Wernher Von Braun Song.
             Re: Shuttle Designs
----------------------------------------------------------------------

Date: 4 Apr 90 01:05:58 GMT
From: amdahl!nsc![e-mail]  (Amos Shapir)
Subject: Re: Velikovsky's Theory

In article <[e-mail]> [e-mail] (Steve Hosgood) writes:
>He postulated that several times in recent (i.e recorded) history, the
>orbits of Mars and Venus were disturbed wildly, and those planets
>came in close contact with the earth.
...
>Things are quieter these days, and it seems highly unlikely that Mars or
>Venus should have strayed from their orbits.

On an astronomical scale, the few thousand year of recorded history
are indistinguishable from "these days".

>However, it seems that current
>thoughts are that the planetary orbits are chaotic in nature (mathematically
>chaotic, that is), and maybe in the light of this , strange things
>could have happened once or twice. Maybe they will happen again, though
>the nature of chaos probably prevents a sensible prediction.

Ah, mathematicians are at it again!  For some reason, they tend to name
mathematical concepts by words that have different meaning in everyday
life.  "Chaotic" in this sense means that a small change in starting
conditions can preclude exact computation of variables in the long run;
however, that doesn't mean that such variables may assume unbounded
values (and besides, "the long run" here is much longer than a few
thousand years).

--
    Amos Shapir
National Semiconductor, 2900 semiconductor Dr.
Santa Clara, CA 95052-8090  Mailstop E-280
[e-mail] or [e-mail]

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

Date: 3 Apr 90 17:10:46 GMT
From: ccncsu!ncr-fc![e-mail]  (Mike McManus)
Subject: Re: Will we lose another orbiter?

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>   Rockwell apparently told NASA early on that they could build three new
>   orbiters for the price of Endeavour, if NASA would relax the specs to
>   allow substitution of compatible equipment rather than insisting that
>   the new hardware be identical to the old.  (Even now there are problems
>   with subcontractors going out of business and tooling being lost, so
>   building an identical orbiter is unnecessarily costly.)  NASA wouldn't
>   go for it.

I can certainly understand the motivation for this decision.  When you change
something, even if it is "compatible", it basically requires a set of tests to
be run to qualify the replacement (what we call "integration testing" where i
work, in reference to software though).  But surely the cost of doing the
qualifying test would be made up in the savings?  Or is NASA more concerned
with opening up themselves to possible risks, with respect to new hardware?  Or
possibly schedule delays?

Every good engineer knows that "if it ain't broken, don't fix it..."  But every
good engineer should also know that there comes a time when you fix it anyway,
because it costs more (in terms of $$$, time, performance) not to!

The tone of Henry's article would seem to indicate that he thinks NASA would be
better off doing some such replacement or equipment (or am I putting words in
your mouth?  :-).  Anybody else thinks so to (I know I do)?
--
Disclaimer: All spelling and/or grammer in this document are guaranteed to be
            correct; any exseptions is the is wurk uv intter-net deemuns.

Mike McManus ([e-mail])
NCR Microelectronics
2001 Danfield Ct.                   ncr-fc![e-mail], or
Ft. Collins,  Colorado              ncr-fc![e-mail], or
[phone]   Ext. 360           uunet!ncrlnk!ncr-sd!ncr-fc!garage!mikemc

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

Date: 3 Apr 90 15:47:16 GMT
From: MATHOM.GANDALF.CS.CMU.EDU![e-mail]  (Donald Lindsay)
Subject: Re: Saturn V gone forever?

In article <[e-mail]>
    [e-mail] writes:
>     I recently attended a panel discussion in which someone commented
>that the technical blueprints for the Saturn V launch vehicle have
>disappeared; that noone at NASA knows where they are (or have gone).
>     I find this incredibly hard to believe.  Does anyone know if this is
>actually true?  And if so, is there any more of story behind the
>disappearance, or are the blueprints *just gone*?

I find this totally believable. When Skylab was coming down, someone
was tasked with trying to control it remotely, so as to keep it up
longer. He couldn't find the documents he needed: he wound up using
the old boy network to try to find individuals who had worked on
various susbsystems. Eventually, he managed to find enough of them
who had taken home personal copies of various manuals, program
listings, and whatnot, and he borrowed these personal copies for the
duration.

This isn't just a problem with NASA. Many of those individuals had
worked for subcontractors, not NASA. Nor is it just a problem with
aerospace: I've seen this sort of thing, myself, in industry.
Sometimes companies go bankrupt: sometimes they screw up: sometimes
they retire a product line: and sometimes they just get out of a
certain line of work.

Personal copies are a Good Thing. _IF_ you can get your employer's
permission, try to take a tasteful amount of material home. Some day
it may be the only copy.
--
Don        D.C.Lindsay     Carnegie Mellon Computer Science

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

Date: 3 Apr 90 18:46:05 GMT
From: haven!uvaarpa!hudson!astsun.astro.Virginia.EDU![e-mail]  (Greg S. Hennessy)
Subject: Re: HST orbit (was Re: Comparative Costs to LEO)

In article <[e-mail]> [e-mail] (Dan Tilque) writes:
#
#The main reason they want the high altitude is due to the current high
#level of solar activity which degrades low orbits.

The main reason they want a high orbit is because the higher you go,
the less the earth blocks out stuff you can see. They always want to
put it as high as they can. Now there is extra incentive to get every
last cm out of the orbit for lifetime reasons, as Mr. Tilque
mentioned.




-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      [e-mail]
 UUCP:        ...!uunet!virginia!gsh7w

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

Date: 4 Apr 90 00:59:13 GMT
From: agate!earthquake.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: What does it cost to push a pound into orbit?

In article <[e-mail]> dbm0000@DOMAIN_2.lerc.nasa.gov (Dave McKissock) writes:
>
>Here at NASA Lewis Research Center, when we perform Life Cycle Cost
>calculations for Space Station we use $3000 / lb for Shuttle
>launch costs.

This says something about NASA.  Your budget is about $6000 a pound for
shuttle costs.

-george

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

Date: 2 Apr 90 15:49:21 GMT
From: cs.utexas.edu!news-server.csri.toronto.edu!torsqnt!lethe!tvcent!comspec!censor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Velikovsky's Theory

In article <[e-mail]> [e-mail] (Steve Hosgood) writes:
>... However, it seems that current
>thoughts are that the planetary orbits are chaotic in nature (mathematically
>chaotic, that is), and maybe in the light of this , strange things
>could have happened once or twice. Maybe they will happen again, though
>the nature of chaos probably prevents a sensible prediction.

Mathematical chaos is not literal chaos.  Depending on details, it may
still be possible to set bounds on the orbit's behavior, even though exact
prediction of future position is not possible.

Chaotic orbits are one thing, and Velikovsky's theories of planets behaving
like demented ping-pong balls in the recent past are another.  The orbits
of the inner planets can be back-tracked for several thousand years using
ancient astronomical observations; the results match modern theory exactly.

>Certainly, Venus has a retrograde spin, and it seems Mars *may* have had
>running liquids on its surface recently enough that the sandstorms have
>not yet removed the evidence. Both of these facts seem a bit odd...

Venus's spin is indeed unexplained.  Last I heard, however, crater counts
had established fairly solidly that Mars's surface water was a phenomenon
of the distant past.  Sandstorms don't "remove" evidence to any significant
degree.  (A trick question that geography profs like to spring on you is:
"Okay, we know that hereabouts, water is the most significant factor in
erosion.  So what's the most significant factor in erosion in a desert?"
Students guess various things; the correct answer is "water".)

>Has Velikovsky's theory held up under attack from supercomputer simulations
>in recent years? ...

Nobody with any real understanding of physics takes Velikovsky seriously.
Attacking his theories with supercomputer simulations would be like attacking
a gnat with a sledgehammer.  Attacking them with a physics textbook suffices.
--
Apollo @ 8yrs: one small step.|     Henry Spencer at U of Toronto Zoology
Space station @ 8yrs:        .| uunet!attcan!utzoo!henry [e-mail]

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

Date: 3 Apr 90 10:10:00 PDT
From: "SSD::COBBHS" <[e-mail]>
Subject: Smithsonian Air and Space Museum
To: "space" <[e-mail]>


                  I N T E R O F F I C E   M E M O R A N D U M

                                        Date:     03-Apr-1990 08:48 PST
                                        From:     HENRY S COBB, 1LT
                                                  COBBHS
                                        Dept:     CLFP
                                        Tel No:   643-2504

TO:  _MAILER!                             ( _DDN[[e-mail]] )


Subject: Smithsonian Air and Space Museum

The following reports are based on my last visit to NASM, about two years ago.

Project West Ford, or "needles in space": leftover hardware is displayed in the
"Apollo to the Moon" gallery, second floor.  The "needles" were actually very
fine copper wires, densely packed in a wax-like substance.  The idea was that
the wax would slowly sublime, releasing the wires.  Differential drag would
spread them into a belt.  The wires were on the order of 8 cm long, which would
make them pretty good reflectors at C-band.  The experiment was apparently tried
only once, and the wires would probably have de-orbited within a year.

"The original Shuttle design:"  NASM is kind to NASA, and doesn't really point
out the original Shuttle design anywhere.  But there was one, and it is
represented in the museum.  In a gallery whose name is something like "The
Science of Flight" (the one with the Hughes racer hanging from the ceiling),
there is a set of high-speed wind tunnel models along the back wall.  One of
these is "the original Shuttle."  It had straight wings, rather than delta.  The
fuselage looks roughly the same.  It's not apparent from the model, of course,
but the fuselage was actually about 60% the size of the current Shuttle.

This design was pretty far along when NASA realized that they needed political
help from DoD.  DoD presented NASA with a set of non-negotiable demands,
including:
   - payload weight and payload bay dimensions, presumably geared to some
     imaging satellite, and
   - a requirement to land at the launch site after one rev in polar orbit.
This latter requirement translates into about 1500nmi. crossrange capability,
which required the delta wings for a higher hypersonic L/D.  The deltas are
heavier and not so much more useful.

In real life, only the payload size requirement has been met.  Max payload
weight for the current generation of orbiters is only about 70% of the 65,000
lb. requirement.  Max crossrange is about 1000nmi., limited by charring of the
OMS pods at lower angles of attack.  And the idea of a one-orbit flight causes
flight controllers to roll their eyes.  Even in dire emergencies, Mission
Control prefers a Rev 3 deorbit to an AOA.  There's no way DoD could do anything
useful in a one-orbit flight.

The original design wasn't perfect, of course.  One minor example: the inertial
navigation units were to be re-aligned in flight using a triple-mount star
tracker in front of the forward windows.  These star trackers looked out through
a non-redundant heat shield door.  If you couldn't close the door, you couldn't
come home.

"Round up the usual disclaimers!"

Cheers!  --Stu  (COBBHS @ AFSC-SSD.AF.MIL)

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

Date: Tue, 3 Apr 90 13:53:14 PDT
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
Subject: Re: Will we lose another orbiter?


In SPACE_DIGEST V11 #204, rochester![e-mail]  (Paul Dietz) rebuts
Lou Adornato as follows:
>>The launch rate had little to do with the Challenger disaster.  A slip of a
>>few days wouldn't have had that big an impact on the annual launch rate that
>>NASA was pushing at that time.  The direct cause of the accident was a mindset
>>...(Lou)
>This is false.  The alternative was waiting until April ("My god,
>Thiokol,..."), when the weather would be warm enough to not be out of
>the range of previous experience.  If they had held, they would have
>had to have held for months, not days.  More broadly, NASA had been
>...(Paul)

    Maybe if you launch from Cape Cod you'd have to wait till April, but
at Cape Canaveral,  you don't generally get winter more than a few days at
a time.
    Just nitpicking.

_____________
Dale M. Greer, whose opinions are not to be confused with those of the
Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER
      While the Bill of Rights burns, Congress fiddles. -- anonymous

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

Date: 3 Apr 90 22:34:30 GMT
From: elroy.jpl.nasa.gov!usc!cs.utexas.edu!samsung!dali!milton!maven![e-mail]
Subject: Wernher Von Braun Song.

I seem to have acquired a FULL set of all of Prof. Tom Lehrer's works.
Her is the one you requested.


Wernher von Braun (by Tom Lehrer)

Gather round while I sing you of Wernher von Braun
A man whose allegiance
Is ruled by expedience.
Call him a Nazi, he won't even frown:
"Nazi, schmazi," says Wernher von Braun.

Don't say that he's hypocritical;
Say rather that he's apolitical.
"Once the rockets are up, who cares where they come down?
That's not my department," says Wernher von Braun.

Some have harsh words for this man of renown,
But some think our attitude
Should be one of gratitude.
Like the widows and cripples in old Londontown
Who owe their large pensions to Wernher von Braun.

You, too, may be a big hero,
Once you've learned to count backwards to zero.
"In German or English I know how to count down,
Und I'm learning Chinese," says Wernher von Braun.


-------------------------------------------------------------------------------
Trendy footer by:
            John Stevens-Schlick
            Internet?: [e-mail]
            7720 35'th Ave S.W. Seattle, Wa. 98126
            (206) 935 - 4384
-------------------------------------------------------------------------------
My boss dosn't know what I do.

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

Date: 4 Apr 90 02:23:18 GMT
From: agate!agate![e-mail]  (William Baxter)
Subject: Re: Shuttle Designs


In article <[e-mail]> [e-mail] (Dave Smith) writes:

>William Baxter writes:
>>Had the promises been based on the detailed design which you [mccall] claim
>>existed, it is unlikely that they would have been so wildly inaccurate.

>Why would this be so?  His claim is that the original design, which would
>have been much more costly in terms of development, would have fulfilled
>these promises.

Yes, this is his claim.  Where do you suppose this 'original design' has
gone?  Is the problem with the shuttle simply that Congress didn't give
NASA enough money to do it right?  In similar circumstances today should
we give them whatever they ask for?

Look at what is happening with the Space Station.  Is there a detailed
and well understood design for Space Station?  Does NASA know how much
it is really going to cost?  Have they answered this question honestly
before Congress?  Have they chosen the best alternative open to them?

It's rather pointless to argue about what went wrong with the shuttle
unless we act to prevent the same problems from arising again.  The
Space Station is now in a stage of development similar to that of the
shuttle at the time of its alleged 'original design.'  What can we do to
avoid similarly disappointing results?  Will it help to throw money at
NASA in the hope that they will do something worthwhile?  Perhaps we
should examine the validity of their promises about Space Station first.

--
William Baxter

ARPA: web@{garnet,brahms,math}.Berkeley.EDU
UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web

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

End of SPACE Digest V11 #217
*******************