Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_1/V10_114.TXT

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Subject: SPACE Digest V10 #114

SPACE Digest                                     Volume 10 : Issue 114

Today's Topics:
    This is *really* weird...  please post when you can...
         Returned mail: Distribution file unreachable
          Re: Risk of NOT launching Galileo
        Re: X-30, Space Station Strangles NASP
       Re: YAHSS (Yet Another Henry Spencer Signature)
        Re: X-30, Space Station Strangles NASP
         Re: What to do with the $30 billion (plans)
               Re: Pluto fly-by
              Re: Trump Station
        Re: X-30, Space Station Strangles NASP
              Magellan summary?
           American Rocket Co. launch date and time
----------------------------------------------------------------------

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Date: Sat, 30 Sep 89 12:26:02 PDT
From: Peter Scott <[e-mail]>
Subject: This is *really* weird...  please post when you can...



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From: Peter Scott <[e-mail]>
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Subject: Re: Saturn V & F-1

uccba!uceng![e-mail]  (daniel mocsny) writes:

>In article <[e-mail]>, [e-mail] (David Palmer) writes:
>> Why not just license the Energiya design from the U.S.S.R.?

>Because stealing the information would be cheaper.

Hey, with _glasnost_ in the air, maybe the Soviets will publish their own
version of _Aviation Week & Space Technology_ and we can just translate the
specs.  Maybe there will even be a Heinrich Uspensersky summarizing it on Sovnet...
 :-)

Peter Scott ([e-mail])

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


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Date: 2 Oct 89 16:22:12 GMT
From: mcsun!mcvax!piring.cwi.nl![e-mail]  (Jack Jansen)
Subject: Re: Risk of NOT launching Galileo

First, let me state that I *do* want to see Galileo launched, and
that I *do* think that the anti-nuke people are overreacting
immensely on the RTG issue. However, I'd still like to comment
on the discussion here.

What annoys me immensely is that most people in this newsgroup
react to the news on Galileo like a four year old whose toy is taken
away: outraged and without any reasonable arguments.

With the exception of Paul Dietz, Henry Spencer and a handful of
other people, most posters come up with such gems as:

- The risk of not launching Galileo is too big.
  Ha! Ha! Ha! Humanity is sooooooooo lucky to have survived these
  millenia without Galileo. Couldn't take the risk of delaying it
  another century or so....

  The truth is that Galileo would be of great benefit to the scientific
  community, and might, maybe, sometime, possibly help us understand
  some important things to our life here a bit better. That's all.

- The windscreens of the shuttle are more dangerous anyway.
  That's a real nice one. Why forbid rape, murder is a lot more serious
  anyway.

And, of course, the ever present
- They're a bunch of un-american technophobe commies, let's ignore
  them.
Which statement I don't feel the need to comment on.

This whole attitude of countering opposing groups with non-arguments
and other crap is *exactly* what got the whole anti-nuke movement
going. The nuclear industry is finally paying the price for 40 years
of misinformation and ignoring public sentiment. Let's learn from
that.

--
--
Een volk dat voor tirannen zwicht    | Oral:     Jack Jansen
zal meer dan lijf en goed verliezen    | Internet: [e-mail]
dan dooft het licht            | Uucp:     mcvax!jack

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

Date: 3 Oct 89 03:43:44 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: X-30, Space Station Strangles NASP

In article <[e-mail]> [e-mail] (SCHREIBER, O. A.) writes:
>Has anybody ever proven that single stage to orbit is possible?

Nobody has ever demonstrated it.  The closest anyone has really come is
1.5 stages with Atlas (which jettisons two out of three engines and some
support structure, but keeps all the tankage).

There is nothing theoretically very difficult about it.  My understanding
is that actual design studies persistently conclude that (a) it looks
workable on paper but (b) the payload fraction is very small.  The
significance of (b) is that even small weight growth in the hardware
will wipe out the payload entirely... and weight growth is virtually
inevitable.

I'm told that with the latest materials, plus altitude-compensating
rocket nozzles, plus pushing the state of the art in structural design
fairly hard, it looks practical, with a modest margin for weight growth.
(This is all-rocket, no airbreathing propulsion at all.)  It sure would
be comforting to see a demonstration, though.  This is one area where
a few hundred million dollars of experiment money might yield a *very*
large payback.

>Also, a hypersonic vehicle has to navigate in a narrow
>velocity-altitude region... too slow and high and it does not climb,
>too fast and low and it melts.

This is one reason why I'm not sold on airbreathing hypersonics as a
route to orbit.  Those two nasty regions actually overlap; there *is*
no magic region of immunity.  Which is why NASP is putting so much
attention into high-temperature materials.
--
Nature is blind; Man is merely |     Henry Spencer at U of Toronto Zoology
shortsighted (and improving).  | uunet!attcan!utzoo!henry [e-mail]

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

Date: 2 Oct 89 08:41:49 GMT
From: sun-barr!oliveb!tymix!hobbes![e-mail]  (Phil Nelson)
Subject: Re: YAHSS (Yet Another Henry Spencer Signature)

In article <[e-mail]> [e-mail] (Games Wizard) writes:

>WHY would Donald trump be interested in space?

>launch facility?  Remember that he wants a 1 mile high facility in N.Y.
>and they wont let him build that!!! (yet)

 This guy is thinking too small, why does he mess around with 1 mile high
when he could be 100 miles high? Why not build a mile-long structure in LEO?
Or, if it's towers he wants, he should build, say, 6 miles high, on the Moon.
Of course, a tower on the moon isn't much use, how about a lunar escape
velocity catapult? still pretty big, and a lot more likely to make some
money back.

 Who is going to be impressed with one more TV tower in NYC? Who needs it?


>            John Stevens-Schlick
>            Internet?: [e-mail]

Phil Nelson at (but not speaking for)                  OnTyme:NSC.P/Nelson
Tymnet, ?McDonnell Douglas? Network Systems Company     Voice:408-922-7508
UUCP:{pyramid|ames}oliveb!tymix!pnelson              LRV:Component Station
"YOUR PASSWORD WAS LAST CHANGED 964 DAYS AGO. IF NOT CHANGED IT WILL BE DELETED SOON!!!" -1022

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

Date: 2 Oct 89 15:43:44 GMT
From: prism![e-mail]  (SCHREIBER, O. A.)
Subject: Re: X-30, Space Station Strangles NASP

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>Actually, I was thinking of space launchers in general rather than
>hypersonic flight in particular -- I'm actually not convinced that
>hypersonic flight is the way to go for cheap spaceflight -- but the

Has anybody ever proven that single stage to orbit is possible?
I remember an engineer from Aerospatiale who was saying that it was not
with the present structural indices possible (weight of fuel/
weight of structure of fuel tank). Perhaps he was not thinking
of airbreathing engine configurations.
Also, a hypersonic vehicle has to navigate in a narrow
velocity-altitude region, between the sustentation barrier and
the thermal barrier: too slow and high and it does not climb,
too fast and low and it melts.
Any opinion?
--
Olivier Schreiber [phone], Office of Computing Services
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp: ...!{allegra,amd,hplabs,seismo,ut-ngp}!gatech!prism!ccsupos
ARPA: [e-mail]

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

Date: 2 Oct 89 21:28:51 GMT
From: cs.utexas.edu!mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: What to do with the $30 billion (plans)

(I'm answering this in pieces, as time permits.)

In article <[e-mail]> [e-mail] (nick szabo) writes:
>>Our lack of complete knowledge about the solar system means that plans may
>>have to be modified in the light of new information, but it does *not*
>>make it impossible or undesirable to *have* a plan.
>
>It does precisely that.  A plan is something to be _followed_, that we get
>locked into.  Imagine a PERT chart for 'The Plan', the Space Station/Moon/
>Mars scenario.  (Ridiculous as this is, I've actually seen one drawn up.)
>Now imagine changing that PERT chart to fit a discovery that in fact the
>asteroids are much better places to put our first space settlements.
>Pretty much have to wipe out the whole thing, don't you?

Why?  The station/Moon/Mars scenario does not include space settlements
at all; the only "settlement" is a base on the Moon, which is justified
in terms of the Moon rather than in terms of it being the best place for
a settlement in general.

More generally, any plan which would be fundamentally changed by certain
quite-plausible discoveries needs to settle those issues *first*.  I assume
we are talking about competently-drawn plans, mind you.  Project Apollo
did not *guess* that the surface of the Moon was solid enough for the LM,
it *confirmed* it, early, with Surveyor unmanned landers.  (The very
first picture sent back by Surveyor 1 was not a panoramic view of the
surroundings -- it was a close-up of Surveyor's foot pad to confirm the
stability of the surface.)  To update the example, any plan which relies
heavily on extraterrestrial resources for their own sake (rather than, say,
lunar resources as a byproduct of lunar exploration) will first have to
settle where the best source is.  That would mean putting very high priority
on geochemical mapping of the Moon (notably, resolving the debated issue
of whether there are frozen volatiles at the lunar poles) and on determining
the bulk (not just surface) composition and mechanical properties of a good
sample of near-Earth asteroids (not just one, and not main-belt asteroids).
This is what planning, as opposed to doing things at random, is all about:
"to do Y we need X, so we'll have to do X first".

Don't confuse planning with drawing PERT charts.  In real life, they are
unrelated.  (Even in theory they are almost unrelated:  you have to know
what to include before you can even consider drawing the silly chart.)
Planning requires thinking, and consideration of alternatives.
--
Nature is blind; Man is merely |     Henry Spencer at U of Toronto Zoology
shortsighted (and improving).  | uunet!attcan!utzoo!henry [e-mail]

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

Date: 3 Oct 89 02:30:17 GMT
From: zephyr.ens.tek.com!wrgate!mrloog![e-mail]  (Dan Tilque;6291545;92-101;OPUS_SW;)
Subject: Re: Pluto fly-by

Henry Spencer writes:
>
>The idea that Pluto might
>be an escaped moon of Neptune has been kicked around for a long time, but as
>far as I know nobody's ever been able to figure out a way to get Pluto from
>Neptune's orbit into its current orbit.

Actually, most escaped moon origin of Pluto theories pretty much bit
the dust when Charon was discovered.  Not only do you have to change
the orbits, but you have to somehow have Pluto capture/retain its
satellite during the ejection event (often a close encounter with
Triton is postuated as the ejection event.  This gives Triton its
backward orbit, thus explaining 2 anomalies for the price of one).

Charon added a completely new set of complications to the escaped moon
theories.

---
Dan Tilque    --    [e-mail]

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

Date: 3 Oct 89 05:25:18 GMT
From: ncrlnk!ncr-sd!crash!orbit!pnet51![e-mail]  (S Schaper)
Subject: Re: Trump Station

But is he launches something like the proposed and defeated French Ring, I say
we test Brilliant Pebbles on it. :^)

UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper
ARPA: crash!orbit!pnet51![e-mail]
INET: [e-mail]

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

Date: 4 Oct 89 00:48:00 GMT
From: usc!venera.isi.edu![e-mail]  (Paul Raveling)
Subject: Re: X-30, Space Station Strangles NASP

In article <[e-mail]>, [e-mail] (Eugene Miya) writes:
>
> Some years back I was looking at X-15 flight paths.  These weren't trivial
> tests, they had to fly all the way to Utah to launch and get to EAFB.
> Imagine what troubles would have been.

    In the case of the X-15 the high speed part needed lots
    surface space, but once the speed dropped the vertical space
    it needed was another attention-getter.  In the worst case,
    inadvertent speed brake deployment, the landing pattern
    was a 270-overhead, entered from 42,000 feet.

    A vertical view of the pattern up to final approach looks like
    a tightening curve with a typical radius of about a mile.  It's
    a 45-degree banked turn @ 300 kt IAS, winding up as TAS
    decreases with altitude, using about 2 minutes from pattern
    entry to touchdown.  Call it about 20,000 fpm descent rate.


    Can any of the NASA folks post info on the shuttle's
    approaches?  Isn't the standard pattern a simple 180?
    What sorts of descent rate or glide slope profile does
    the shuttle have as a function of altitude & airspeed?


----------------
Paul Raveling
[e-mail]

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

Date: 3 Oct 89 04:24:11 GMT
From: datapg!com50!questar![e-mail]  (Al Viall)
Subject: Magellan summary?

In the wee days before the launch of another planetary probe, does anyone
have any news and/or statistics on Magellan??

Another question. Looking through the press release for Galileo, to which
I thank Peter Yee for sending through the net, I had read that the craft
would make a double earth flyby(i.e. the VEEGA track).
Why was this track chosen, considering that it would be more fruitfull to
just get the craft to Jupiter in one piece.
I am not bunking the experts at JPL and Ames, don't get me wrong, I am sure
they had there reasons, such as ' While it's out there, let's take advantage'.

- Al -

--
  | INTERNET: [e-mail]  |  FLASH: "Dan Quayle's face    |
  |     UUCP: ..!amdahl!tcnet!questar!al | seen on Mars" It Looks Puzzled|
  |   "Uhh, Excuse me while I take a moment to adjust my tribble."       |
  ------------------------------------------------------------------------

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

Date: 3 Oct 89 21:18:16 GMT
From: gem.mps.ohio-state.edu!usc!aero![e-mail]  (Thomas F. Smith)
Subject: American Rocket Co. launch date and time

The AMROC launch of the "Koopman Express"
is currently scheduled for 5 OCT 89,
10:28 am from Vandenberg Air Force Base, California.
Launch azimuth will be 270 degrees.

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

End of SPACE Digest V10 #114
*******************