Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_6/V15NO615.TXT

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Date: Thu, 31 Dec 92 05:10:05
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #615
To: Space Digest Readers
Precedence: bulk


Space Digest                Thu, 31 Dec 92       Volume 15 : Issue 615

Today's Topics:
                        averting doom (3 msgs)
       Comparative $/lb to LEO (Was: Stupid Shuttle Cost ArgumZ
                      Galileo Update - 12/30/92
Government-run programs  Was: Re: Justification for the Space Program (3 msgs)
     I thinI see our problem. (Was Re: Terminal Velocity of DCX?
             Justification for the Space Program (2 msgs)
                     Moon Dust For Sale (2 msgs)
                       Saturn lift capabilities
                       SSTO vs 2 stage (2 msgs)
   Stupid Shut Cost arguements (was Re: Terminal Velocity (2 msgs)

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

Date: 30 Dec 92 21:36:04 GMT
From: Thomas Clarke <[e-mail]>
Subject: averting doom
Newsgroups: sci.space,sci.physics

In article <[e-mail]> [e-mail] (John
McCarthy) writes:
> By the way, it seems to me that if the above idea is sound, it settles
> the question of the stability of the solar system - in the negative.
> Very likely an asteroid could be tamed over a sufficiently long time
> with as small an expenditure of delta-v as might be desired.  Once
> tamed it could be used with infinitesimal external force to expel a
> planet from the system.  This tells us that the current trajectory of
> the solar system is arbitarily close to one in which a planet is
> expelled.  Of course, the probability that a planet actually would be
> expelled by this mechanism in some particular finite time is extremely
> low, because maintaining the required sequence of encounters requires
> an improbable precision in the initial conditions.  I suppose a lower
> bound on the probability could be computed and from it an expected
> upper bound on the gravitational lifetime of the solar system could be
> obtained.

Hurray!  My Douglas Adamsian speculations were not totally hougwash :-)

More seriously, In the most recent Sci Am or Sky and Telescope
(I was reading both last night and get confused) there is piece about
work by the group at MIT with the special purspose celestial
mechanical computer (sorry for vagueness, but mags are at home)
concerning chaotic dynamics in the solar system.  The original work
is reported in a July issue of Science, but I missed the original.

The upshot is they simulated the solar system's dynamics for some 100
million years and made several runs after slightly (1 millimeter !)
perturbing the position of each planet.  The article showed a graph
of the expeonential (hence chaotic) divergence in the position of
Pluto for the 1 mm perturbation in Venus's position.  After 100 myear
Plutos position had changed by quite some million miles.

Hey, maybe Pluto would be better than Ceres.  Kick a periodic comet
so it ricochets of Pluto.  Pluto Ricochets off Neptune, then off Jupiter
and into the inner solar system where it becomes tame!

--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: 30 Dec 92 21:36:49 GMT
From: Thomas Clarke <[e-mail]>
Subject: averting doom
Newsgroups: sci.space,sci.physics

Newsgroups: sci.astro
Path: cs.ucf.edu!news
From: [e-mail] (Thomas Clarke)
Subject: Re: averting doom
Message-ID: <[e-mail]>
Sender: [e-mail] (News system)
Organization: University of Central Florida
References: <[e-mail]>
Date: Wed, 30 Dec 1992 19:41:39 GMT

In article <[e-mail]> [e-mail] (Thomas
Clarke) writes:
> In article <[e-mail]> [e-mail] (John
> McCarthy) writes:
> > By the way, it seems to me that if the above idea is sound, it settles
> > the question of the stability of the solar system - in the negative.
> ... In the most recent Sci Am or Sky and Telescope

It was Sky and Telescope Feb '93 ppp 13-14.
I remembered wrong.  A one millimeter perturbation of Mars' orbit
eventually caused a 500,000 kilometer difference in the position of
Pluto after 100 million years.

Gerald Sussman and Jack Wisdom used the Supercomputer Toolkit at MIT
to simulate the solar system.

>Hey, maybe Pluto would be better than Ceres.  Kick a periodic comet
>so it ricochets of Pluto.  Pluto Ricochets off Neptune, then off Jupiter
>and into the inner solar system where it becomes tame!

A further thought:  sprinkle carbon black on the right part of the
comet and its natural outgassing will be modified.  Done properely
in an orbit or two the comet will ricochet of Jupiter then into
Pluto and away we go.
This is a mission we could fly now!! A few hundred pounds of carbon
black in a comet fly by!  I wonder is the MIT computer is up to
predicting comet outgassing :-)

--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: 30 Dec 92 20:55:27 GMT
From: Henry Spencer <[e-mail]>
Subject: averting doom
Newsgroups: sci.astro,sci.space,sci.physics,sci.environment

In article <[e-mail]> [e-mail] (Andrew - Palfreyman) writes:
>I like the simplicity of this idea (moving the Earth instead of
>trying to shield it), but what the heck's all this "elastic
>collisions" stuff? ...
>Instead, I'd use the "tame asteroid" in a resonant slingshot
>configuration between (say) Mars and Earth...

That's what he's proposing.  It turns out that gravity-assist maneuvers,
viewed from a distance, have exactly the behavior of elastic collisions
and can be analyzed as such.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 30 Dec 92 22:08:44 GMT
From: [e-mail]
Subject: Comparative $/lb to LEO (Was: Stupid Shuttle Cost ArgumZ
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Brian Stuart Thorn) writes:
>>Maximum payload weight for a safe abort is
>>40,000 lbs, and the shuttle rarely carries that much weight.
>
>      Not true in either statement. 40,000 lbs. is about the average, if I
>      reckon correctly. However I'll have to dig up copies of the Shuttle
>      Press Kits for each mission to get an accurate figure. Many missions
>      have been above the 40,000 lb. mark (STS-29, STS-30, STS-34, STS-41,
>      STS-37, STS-43, STS-44, STS-50, all since return-to-flight.) Many of
>      the military missions used the IUS, making them candidates for
>      40,000+ payloads. The next 40,000+ mission is in two weeks: STS-54.
>
>      The "abort" figure you cite appears to be based on the safe return
>      weight (about 35,000lbs) but this has not been a factor in limiting
>      Shuttle payload capacity, as the above examples testify.
>
>      -Brian


Below is a table listing the shuttle payload weight for non-classified
flights.  The weight given is the combined weight of the attached and
deployed payloads in the payload bay.  It does not include the weight of
the mid-deck experiments.

  10K - 20K#      20K - 30K#      30K - 40K#      40K - 50K#         50K# +
  -----------    ------------    ------------    ------------    ------------
   1 - 10,823     52 - 20,132      8 - 30,076    51I - 43,988    51L - 52,308
  48 - 17,144     39 - 21,413    51B - 31,407     41 - 44,107
  45 - 17,683      3 - 22,710    61A - 31,861    51G - 44,477
   2 - 18,778    41G - 23,465      5 - 32,080     44 - 44,637
                   4 - 24,492    61C - 32,462    51A - 45,306
                  32 - 26,488     50 - 32,477     30 - 45,930
                  47 - 28,092     49 - 32,809     26 - 46,478
                  40 - 28,114      9 - 33,264     34 - 48,643
                  53 - 28,346    41B - 33,868     43 - 46,712
                  46 - 28,585    51F - 34,400      6 - 46,971
                  42 - 28,663    51D - 35,824    41D - 47,516
                  31 - 28,673     37 - 36,800    61B - 48,041
                  35 - 29,806      7 - 37,124
                                  29 - 38,097
                                 41C - 38,266

Total weight launched in 45 flights = 1,519,336 pounds
Average payload weight per flight   =    33,763 pounds

Note:  This does not include the following DoD flights: 51C, 51J, 27, 28,
       33, 36, and 38.

--

Pat Oliver -      Lockheed Engineering and Sciences Company at NASA JSC
        [e-mail]
        All standard disclamers apply.

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

Date: 30 Dec 92 22:37:00 GMT
From: Ron Baalke <[e-mail]>
Subject: Galileo Update - 12/30/92
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Forwarded from:
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109.  TELEPHONE [phone]

                     GALILEO MISSION STATUS
                        December 30, 1992

     The Galileo spacecraft is operating normally in the dual-
spin mode and is transmitting coded telemetry at 1200 bits per
second.  It is about 16.5 million kilometers (10.25 million
miles) from Earth, and about 152 million kilometers (94 million
miles) from the Sun.

     Yesterday, December 29, after approximately 20 hours of
warming in sunlight, the antenna-deploy motors were turned on to
"wind up" the system and then pulsed to "hammer" it in an effort
to free the stuck ribs of Galileo's high-gain antenna.  The
procedures began at 6:55 a.m. PST and continued until 2:48 a.m.
PST this morning, December 30.  A total of 2160 pulses were
executed by the motors during this period.  The stuck ribs were
apparently not freed.  This morning the spacecraft was returned
from the warming attitude to the normal cruise mode.

     No spacecraft activities are scheduled during the holiday
weekend.  Activities will resume next week.

                              #####
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life.

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

Date: Wed, 30 Dec 1992 21:15:12 GMT
From: "John S. Neff" <[e-mail]>
Subject: Government-run programs  Was: Re: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>From: [e-mail] (Allen W. Sherzer)
>Subject: Re: Government-run programs  Was: Re: Justification for the Space Program
>Date: Wed, 30 Dec 1992 20:39:37 GMT
>In article <[e-mail]> Dr. Norman J. LaFave <[e-mail]> writes:
>
>>>prevented from some action.  The government doesn't subsidize mountain
>>>climbing; why should it subsidize much more expensive space escapism?
>
>>The fact that you can equate these two things just shows how
>>out of touch with reality you really are.
>
>Oh I don't know about that. I see lots of similarities. Both climbers and
>astronauts are small groups of well trained people. Both spend lots of
>money to do what they do. Both are limited to letting very small numbers
>of people do something exciting. After all, I will never climb Mt. Everest,
>nor (the way things are going) will I ever go into space.
>
>Now you might argue that space is the future of mankind and that a
>spacefaring civilization is more important than rock climbing. I aggree
>with that but must point out that if you think current government space
>activity has anything to do with that then YOU are the one out of touch.
>
>  Allen
>
>--
>+---------------------------------------------------------------------------+
>| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
>|  [e-mail]     |  nothing undone"                                       |
>+----------------------115 DAYS TO FIRST FLIGHT OF DCX----------------------+

Most polls show that the public wants a manned space program, and they
are willing to pay for it. Why do they want a manned space program? During
the Apollo Program the answer was obvious, today it is not obvious, at least
to me, why they want one.

When JFK gave his speech in 1961 he talked about intangible benefits from
an effort to put AMERICANS on the moon. I don't recall that he said anything
about science and technology as a reasons for making the effort. There were
many benefits including scientific and technical ones from the Apollo
program. Was the money well spent? I think most people would say yes.

Today we have AMERICANS in space on an occasional basis, with the possibility
of more or less continuous presence of AMERICANS in space within the next
decade. Is this worth what it costs? If the majority of the people think
so we will keep on with this program, if not we won't. There is no such
thing as an inexpensive space program and in particular a manned space
program. If we worked hard at mundane things like industrial engieering
we might be able to reduce the cost of placing something in LEO by
perhaps 50%. That would be a good thing but it will not make it possible
for Joe Six Pack to vacation in space.

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

Date: Wed, 30 Dec 1992 21:41:18 GMT
From: Paul Dietz <[e-mail]>
Subject: Government-run programs  Was: Re: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> [e-mail] (John S. Neff) writes:

> Most polls show that the public wants a manned space program, and they
> are willing to pay for it.

You have to be careful with polls.  A poll in which people are asked
"do you want a manned space program?" will ellicit a generally
positive response.  However, similar questions on other issues, like
education, health care, and so on, ellicit much more positive
responses.  The *relative* support of the space program is not very
high.

Followup to talk.politics.space.

    Paul F. Dietz
    [e-mail]

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

Date: 30 Dec 92 21:29:06 GMT
From: "Dr. Norman J. LaFave" <[e-mail]>
Subject: Government-run programs  Was: Re: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> Allen W. Sherzer, [e-mail]
writes:
>Now you might argue that space is the future of mankind and that a
>spacefaring civilization is more important than rock climbing. I aggree
>with that but must point out that if you think current government space
>activity has anything to do with that then YOU are the one out of touch.

Actually, that is exactly what I am arguing. Unlike you though, I see
the benefits derived from NASA's activities. Are there problems? yes.
Should NASA be doing commercial launches? Absolutely not. However,
to contend that NASA is a failure is to ignore that all pioneering
work started with a few individuals and a dream willing to make the
sacrifices to make their dream a reality. That step has been taken. NASA
should turn the commercial activities over to corporations and return to
doing cutting-edge scientific research, period.

Norman

Dr. Norman J. LaFave
Senior Engineer
Lockheed Engineering and Sciences Company




When the going gets weird, the weird turn pro
                               Hunter Thompson

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

Date: 30 Dec 92 22:46:01 GMT
From: "Edward V. Wright" <[e-mail]>
Subject: I thinI see our problem. (Was Re: Terminal Velocity of DCX?
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Gary Coffman) writes:

>Better ask how many Wright Flyers are still in operation. That's
>a closer approximation of where we are in spaceflight relative
>to aeronautics. And don't forget to check on how many DC-1s and
>DC-2s are still doing scheduled flights.

The DC-1/2/3 were all essentially the same aircraft, Gary.

Have you *ever* posted a historical fact that wasn't wrong/silly? :-)

>To compare aviation and spaceflight, go back in aviation history
>to where the total number of hours of powered flight of all aircraft
>equal the total number of hours of powered flight for all launchers.
>We're still at the sticks and string level. Actually, I'd claim we're
>back with the Montgolfier brothers.

You'd also claim that the Montgolfiers were wasting their time,
because man would never fly...

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

Date: 30 Dec 92 20:21:56 GMT
From: "Dr. Norman J. LaFave" <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> Mark Benson,
benson@gemed writes:
>    We now return to the discussion of the Nirvana of SSTO vs. the hell
of STS.
>    (I like 'em both - but zealots can't admit anyone elses viewpoint has
>    value.)

I can and I am a zealot.

Norman

Dr. Norman J. LaFave
Senior Engineer
Lockheed Engineering and Sciences Company




When the going gets weird, the weird turn pro
                               Hunter Thompson

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

Date: Wed, 30 Dec 1992 21:07:27 GMT
From: "Dr. Norman J. LaFave" <[e-mail]>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]> Paul Dietz,
[e-mail] writes:
>Let me try this again: your historical argument is just bullshit.  The
>reasoning is vacuous, independent of the truth of the conclusion.
>There are too many differences between then and now to accept the
>argument as anything more than sloganeering.

Maybe you would like to state these supposed huge differences
which negate my arguement instead of waving your hands....

>For example: (1) the
>vessels they used to explore were straightforward extensions of known
>technology,

Oh, so rockets used for space exploration sprung from the ground as
seedlings?
Does the word Buzz-bomb mean anything to you? Does the name X-15 mean
anything. The fact IS that the present vehicles are extensions of known
technology!

>(2) the lands explored did not involve significant
>differences in technology in order to survive [those that did, like
>the high Artic, were left largely alone for centuries],

Note how you convenently leave out deep-sea exploration which
has recieved significant exploration and did require technology
development. How about the exploration of the high energy world?

(3) the
>resources they found could be exploited at low cost and yet returned
>benefits large in proportion to the size of their economies.  These
>conditions don't appear to apply to space.

Since we have done little in the area of exploiting space yet, this
is pure speculation. Furthermore, satellite communication and
weather monitoring has been quite profitable thank you very
much.

>
>The track record so far in space is that some limited automated
>applications are useful, or profitable (comsats are profitable, at
>least for the moment; the others are government-run, so we don't know
>if they really would be profitable.)  Space resources?  We went
>to the moon and found... very little of practical value.

The knowledge we gained, by itself, was worth the cost.

>Space
>manufacturing?  Endlessly hyped with little to show for it.

Since nobody has done any space manufacturing, this is mere
speculation and a vacuous arguement.

>Microgravity research?  Impartial scientific review says it isn't
>worth much.

Maybe you would like to cite this so-called impartial review?

>
>You advance the straw man argument that I am arguing that there will
>never be any benefits.  As you say, we can't know that.  But lack of
>certainty doesn't mean we are absolved from the need to make decisions
>on how scarce funds are expended.

Right. The choices are:

a.) Fund only safe, incremental research and wallow in stagnation.
We could be penny-wise and pound foolish while our international
competitors continue to kick our economic butts.

or b.) Return to the bold, risk-taking, adventurous, society we use
to be and return to prosperity.

>You can't just say "you can't prove
>me wrong, so gimme."  At least, not with a straight face.

But I can say that there is an extremely high probability, based on
historical precedent, that you are wrong. That should be more than
enough reason to fund bold initiatives like space exploration...
unless we want to continue to act like a country of panty-waists...

Norman

Dr. Norman J. LaFave
Senior Engineer
Lockheed Engineering and Sciences Company




When the going gets weird, the weird turn pro
                               Hunter Thompson

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

Date: 30 Dec 92 21:03:35 GMT
From: Henry Spencer <[e-mail]>
Subject: Moon Dust For Sale
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>...2 inch piece of transparent tape which has some Moon dust on it.  This is
>the first time that Moon dust is being offered for sale.   The Moon dust
>was collected by a NASA technician from the spacesuit of astronaut Dave Scott
>after his Apollo 15 trip to the Moon in July, 1971.  It is guarantteed
>to be genuine by Superior Galleries and is expected to be sold
>in the price range of $75,000 to $100,000...

For anyone with $100k to spare who's feeling interested :-), note that
unless things have changed recently, the ownership of this Moon dust is
best described as "disputed".  NASA's position is that all, repeat all,
lunar material returned by Apollo is US government property, and any
offered for private sale is stolen goods.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 30 Dec 92 21:54:02 GMT
From: USENET News System <[e-mail]>
Subject: Moon Dust For Sale
Newsgroups: sci.space,sci.astro,alt.sci.planetary

could use the bread to defray current operating costs.
From: [e-mail] (Marcos Salganicoff)
Path: grip.cis.upenn.edu!sal

Seriously, I think its kind of sleazy for that technician (whomever
they were) to make off with the moon dust that was gotten on a trip
funded by the public, even if accidentally so.

Oh well, no one ever said life was fair.

Marcos Salganicoff

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

Date: 30 Dec 92 20:58:02 GMT
From: Henry Spencer <[e-mail]>
Subject: Saturn lift capabilities
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>    Given the opinion of the science community on ASTP,
>    why didn't we have the  ASTP mission meet at Skylab? ...
>    Was skylabs orbit too low in inclination for them to hit it?

No, the inclination was pretty much compatible... but Skylab's orbit was
simply too high for a standard Soyuz to reach.  Having a Soyuz dock to
Skylab (while a US crew was there!) was one of the ideas discussed early
on in the planning for what became ASTP, but it didn't seem feasible,
for altitude and other reasons.
--
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  [e-mail]  utzoo!henry

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

Date: 30 Dec 92 21:15:06 GMT
From: Charles Pooley <[e-mail]>
Subject: SSTO vs 2 stage
Newsgroups: sci.space

People keep debating the merits of 2sto vs ssto, and are overlooking what
I think is the main consideration.

In climbing and accelerating to orbit it can be said there are 2 distinct
environments in which the rocket operates.  Near liftoff, there is
substantial atmospheric pressure and aerodynamic loads as the rocket
accelerates through 'max-q' and towards the 2nd environment: near vacuum
conditions at altitudes above about 200,000'.

So, for the 1st environment, the 1st stage should have the durability to
cope with the aerodynamic loads and have engines optimised for use in
atmpsphere.  As the velocity attained by the 1st stage will be less than
the exhaust velocity, the mass ratio and specific impulse will be moderate.

Also, a means of recovery would be built into the 1st stage (but not nec.
the 2nd).  The 1st stage might also have a shroud to contain and protect
the 2nd (for small rockets, at least).

The 2nd stage will have the highest Isp possible, a large nozzle for the
vacuum conditions, and little or no consideration for aerodynamics.

The general idea, it seems, is not to take any component or capability
of the rocket past the point it is needed.  ie, wings, landing gear,
parachutes, rugged construction etc for low altitude conditions not go
beyond staging point.  The Saturn V is a good example--O2/RP1 for 1st
stage and H2/O2 and vacuum operating engines for altitude.
--
Charles Pooley                  [e-mail]    GEnie  c.pooley
EE consultant, Los Angeles, CA

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

Date: 30 Dec 92 22:51:02 GMT
From: "Edward V. Wright" <[e-mail]>
Subject: SSTO vs 2 stage
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Paul Dietz) writes:

>The mass ratio on an airliner is much less than in a launcher with
>chemical rocket propulsion, for rather fundamental reasons.  It is
>therefore not inconceivable that multistage launchers would be
>appropriate even though multistage aircraft are not.

I didn't ask if you could say "It is not inconceivable."  I asked
if you could prove it.

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

Date: Wed, 30 Dec 1992 20:59:40 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:

>>Considering that there are no heavy payloads to return to Earth, this
>>cannot be considered an advantage. Especially for the billions it costs

>>us.

>    GRO and UARS are both candidates for return to earth.

Doing that would cost more then they are worth. It would be cheaper to
build new ones and launch them commercially.

>    LDEF and

LDEF would have been better flown as a series of smaller platforms.
Under those conditions it would be simple to build a vehicle which
returns them to Earth. That way each experimenter would get custom
time on orbit and the taxpayers would save billions.

>    The Hubble repair could still prove too much for orbiting
>    astronauts and thus require return to Earth for mirror replacement,

No for two reasons: 1) it would be cheaper to build another and fly it
and 2) in testimony before the House the program manager said Hubble
wouldn't survive the return trip.

To date there are no payloads which can be returned by Shuttle in a
cost effective manner.

>    All I'm saying is that Shuttle
>    did not meet its objectives, so don't be so sure about DC.

Same old arguement. I guess Boeing better cancel plans for the 777.
After all, Shuttle failed so 777 will as well.

>    A few weeks ago I mentioned one way that we could have kept some of
>    that market in the U.S. until NLS, DC or whatever was ready. You
>    said that it (maintaining Shuttle launches of commercial payloads)
>    was too costly. Maybe so (definitely so) but those subsidies would
>    have at least kept customers in the U.S.

And at the same time killed any chance of a sustainable independent
commercial effort. If your going to do that it would be cheaper to
simple end all space activity.

>    Why wasn't DC-X built in 1983

You mean when the government was spending billions killing competition
with Shuttle subsidies? You can't be serious; who would be that stupid?

>    your argument that the next generation of boosters be a commerical
>    endeavor? What is it they say about building a better mousetrap?

It is hard to convince investors when they see that the largest customer
doesn't care about cheaper costs.

  Allen

--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------115 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: 30 Dec 92 22:11:00 GMT
From: Bob Koehler <[e-mail]>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Allen W. Sherzer) writes...
>In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
>
>>>Considering that there are no heavy payloads to return to Earth, this
>>>cannot be considered an advantage. Especially for the billions it costs
>>>us.
>
>>    GRO and UARS are both candidates for return to earth.
>
>Doing that would cost more then they are worth. It would be cheaper to
>build new ones and launch them commercially.
>

Can you show that was also true for SMM?  Part of the MMS on UARS is from SMM,
having been brought back after a successfull mission, after earlier being
repaired in orbit.  SMM isn't planning to reuse itself, and neither UARS nor
GRO may be either, but there has already been cost savings on UARS due to the
return of SMM.  Only the shuttle (product of politics more than NASA's
technical or mangement expertise IMHO) could repair SMM, and only the shuttle
could bring it back.

------------------------------------------------------------------------------
Bob Koehler                     |   Any illusion to these opinions being other
[e-mail]   |   than just mine alone is just that.

 " Life is life, and fun is fun, but it's all so quiet when the goldfish die. "
                         - Blixie

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End of Space Digest Volume 15 : Issue 615
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