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Subject: SPACE Digest V13 #562

SPACE Digest                                     Volume 13 : Issue 562

Today's Topics:
              Re: Why the space station?
       Re: Ethics of Terraforming (was Re: Terraforming Venus)
              how to order space prints
              Re: Why the space station?
          Human Expansion (Was Honking at cyclists)
          Re: SPACE STATION FREEDOM WOUNDED
              Re: Why the space station?
               Re: Saturn V and the ALS
                  Shuttle C
               Re: Saturn V and the ALS

Administrivia:

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

Date: 15 May 91 16:26:57 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Why the space station?

In article <[e-mail]> [e-mail] (Fraering Philip) writes:
>Mars will not be as easy to quantify with an Apollo-style sampling
>as the moon was...

Especially since the Moon wasn't "quantified", in any realistic sense of
the word, by Apollo.  *Every* Apollo landing brought back at least one
previously-unknown type of lunar rock.  There weren't enough of them to
even give us good qualitative knowledge, never mind quantitative.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 15 May 91 09:36:38 GMT
From: swrinde!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Ethics of Terraforming (was Re: Terraforming Venus)

In article <[e-mail]> [e-mail] (Frank Crary) writes:
>In article <[e-mail]> [e-mail] (Lon Stowell) writes:
>>But what about the face?  (Does anyone else think it sorta looks
>>like Maggie Thatcher?)
>>
>The Earth is full of rock formations that "look like" someone or
>something special. To my knowledge, only one (on Earth) is man-made.

Mt. Rushmore, Crazy Horse, and the Confederate diorama on Stone Mountain
to name but three here is the US are manmade. They are quite common around
the world.

Gary

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

Date: 15 May 91 19:23:42 GMT
From: beaver![e-mail]  (David Doll)
Subject: how to order space prints


Hello, I just saw a wonderfull photo in the Dec 1990 issue of Popular
Science. It had a edge on shot of the Milky way taken from the Cosmic
Background Exporer. Does anybody know where or how I could order a
print of it? Hmmm, I gues I should say where/how I could any of the
amazing photos taken from various NASA/JPL/etc projects. Could you
please e-mail me. Thanks for your time.

--
David Doll
Computer Science and Engineering
Univ. of Washington
Seattle, WA 98195
MS: FR-35
[phone], 543-5075
[e-mail]

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

Date: 15 May 91 23:10:35 GMT
From: agate!headcrash.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: Why the space station?

In article <[e-mail]> [e-mail] (Ken Sheppardson) writes:
>[e-mail] (George William Herbert) writes:
>>        There are vaild reasons to question the whole truss-layout concept,
>>number one being still-unanswered (as far as I've seen in trade press)
>>questions about the repair EVA efforts.
>
>  I agree with you 100%. I think very few folks in NASA wouldn't.

    Well, then, it's sort of silly to insist we go with a configuration
that may have a significant unanswered flaw...  besides, we _still_ don't
have funding for a Space Station Suit for the EVA work.  [no, the uprated
shuttle suit doesn't count.  It's maintenance needs are too high.]  Funding
a station suit for 93-5 production ought to be a priority, but isn't...

>[..]
>  That 'same capability' question is important. Hold that thought.
>
>  And just how would you have us go about proving the 'efficiency' of a
>  design? What are your criteria?

Frank Crary's response is pretty on target.

>>station? yes.  Which would be cheaper?  Probably not Freedom.
>Is that just a gut feeling or do you have numbers? We certainly don't.

You're going to be building this thing... If you don't do basic configuration
tradeoff studies, there's been an organizational failure...

>  'Efficiency' has very little to do with it. Let's get back to that point
>  you raised about Mir having the 'same capabililty' as Freedom.

    I did not state that Mir would or does have the same capability.
I in fact used the word 'Mir-oid' to indicate that I was only refering to
the multi-can type design, not the exact Mir configuration.  Obviously,
a Freedom-comparable can station would have to be as big as Freedom (module
wise), maybe slightly bigger due to some systems being inboard.  ...

>  Let my pose a purely hypothetical situation to you. You're designing a
>  space station. It's over budget. You're asked to 're-st...' er... I
>  mean 'descope' your station to fit budget constraints. You're given the
>  following set of requirements.
>
>     1) Reduce cost
>     2) Use existing designs wherever possible
>     3) DO NOT reduce available power
>     4) fully utilize all hardware you launch (i.e. don't launch any
>        unused capability)
>
>  The existing designs call for sun tracking photovoltaic arrays placed out
>  on the ends of long booms to provide clearance for them to rotate 360 deg
>  and to reduce/eliminate shadowing. Alright, now propose a configuration
>  which meets the above requirements. I challenge you to come up with a
>  configuration which doesn't put the PV arrays out on the ends of long
>  booms where they can fully track the sun.

Well, let's do a hypothetical weight tradeoff:
    Power Required: 25 Kw (sun-side duty cycle=0.5; 8Kw actual const. draw
    plus battery charge penalties for darkside)
    Truss-station
        Oriented solar cell area req: 180 m^2
        Est array weight: ~20kg/m^2 = 3600 kg
        Est truss wt: (wild blue) 3400 kg
        tot sys wt: 7 tons
    Can-station
        Semi-oriented array area: 360 m^2  *
        Est Array Weight: 7200 kg
        tot sys wt 7.2 tons

* I've pessimistically assumed that the effective effeciency of a non-3D swivel
array is only 0.5  The systems are equivalent.
    Larger arrays offset the truss weight.  The truss details are very
dependent on other factors.  My point is that it's as effecient to have
larger less-effecient panels if you don't have to fly the weight of a truss
or assemble it...

>  Now let's say we wantet our station to look at an existing station,
>  oh, say, Mir. Mir has PVs sticking out all over the place from (almost)
>  every module. I believe the PV arrays have at most one degree of freedom
>  each. Not only can the arrays not track the sun 100%, but the layout of the
>  modules causes severe shadowing problems. Mir therefore violates
>  Requirement #4 as stated above.

We could avoid this by using longer but less panels.
Mir is using fixed-size panels for a specific reason.  More creative station
configurations are perfectly possible.  I don't suggest we copy Mir exactly;
it's got some easily-avoidable flaws 8-)

>  Of course, if this where a real-life situation, you'd have non-technical
>  issues to deal with, but as I said, this is only a HYPOTHETICAL situation.

There's nothing hypothetical about it at all.  Freedom is what NASA wants to
fly, and it may well be a fatally flawed station concept.  The USA is not
rich enough to spend that sort of money on a dud.


  == George William Herbert ==   *   JOAT = Jack Of All Trades = Generalist   *
 == JOAT for Hire: Anything, ==  #########  I do Naval Architecture, ##########
===+++ Anywhere, my price +++=== # Spacecraft Design, UNIX Systems Consulting #
 ==   [e-mail]   ==  # RPG writing/development, and lots of other #
  ==   [e-mail]   ==   ## random stuff, of course.  I'm a JOAT 8-) ##

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

Date: 15 May 91 23:32:06 GMT
From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!think.com!spool.mu.edu!news.nd.edu!mentor.cc.purdue.edu!noose.ecn.purdue.edu!en.ecn.purdue.edu![e-mail]  (/dev/null)
Subject: Human Expansion (Was Honking at cyclists)

I just picked up _Interstellar_Migration_and_the_Human_Experience_.

I think it should be read by quite a few people.

I agree with ne of the overriding notions in the book:  The
expansion of man will not stop - there is nothing we can do to even
significantly delay this. (Short of Nukewar... :) )

Cool book.  Thanks to whoever reccommended it on the net!


--
+-----------------------------------------------------------------------+
| Cogito ergo sum...|  Brent Irvine     ([e-mail])    |
| Bibio ergo sum... | These opinions are mine...as if they counted! :)  |
+-----------------------------------------------------------------------+

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

Date: 16 May 91 02:16:00 GMT
From: rochester!sol![e-mail]  (Brian Yamauchi)
Subject: Re: SPACE STATION FREEDOM WOUNDED

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>>In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:

>>>The House HUD/VA/IA Appropriations Subcommittee marked up the NASA
>>>appropriation this morning. They zeroed out ALL station funding.

>>And once again, the U.S. shows that it is not a partner to trust in
>>international space projects.

>That happened long ago. Either we where unreliable because we didn't
>have a working station or we are unreliable because we killed it when
>it became obvious it wasn't working. The latter saves us $100 billion.

My question is how much of this money will actually go to space
science and unmanned space exploration.  I'd rather have a lot of
Mariner Mark IIs, planetary rovers, and microprobes than Freedom, but
I'd rather have Freedom than nothing...
--
_______________________________________________________________________________

Brian Yamauchi                University of Rochester
[e-mail]        Department of Computer Science
_______________________________________________________________________________

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

Date: 15 May 91 16:17:07 GMT
From: usc!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Why the space station?

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

>Returning Martian polar samples wouldn't require any sort of assembly.
>You would land a small drilling rig on the pole, bring up a nice
>long thin core, take pictures of it as it came up, and chop pieces
>out of it at intervals for on-site analysis or return to earth
>via rendesvous and sample transfer in Martian orbit.  The lander/drilling
>rig is all one piece, the orbiter is a separate peice.  There is no
>benefit from assembly; forcing assembly on the mission could
>severely handicap the functions.

You don't understand; I'd like to see several dozen of these as a start,
from dephs ranging from the surface to several km down.

With on-site selection.

For _that_ mission, ET resources and on-orbit assembly (maybe from
those resources) would be neccesary.

--
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: 15 May 91 20:33:56 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>go to McDonnell Douglas and Martin and tell them: "OK, go ahead". We
>could end up saving 90+% of the NLDP development costs. On the downside,
>we will add maybe 5% to NLDP cost if it fails. Isn't that worth the
>risk?
>
I'm not sure that Martin or Douglas could come through... My point was
that neither company expected the governemt to give an "OK, go ahead" sort
of answer. Thier  cost estimate might be low, since they did not expect
to be held to an initail offer's price. But, hell, we might as well
see if they could... If their numbers ARE right, it would be worth it.
And if their price is off (and they know it) they get to look stupid.


                 Frank Crary
                 UC Berkeley

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

Date: 15 May 91 15:28:33 GMT
From: aio!vf.jsc.nasa.gov![e-mail]
Subject: Shuttle C

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

> It is only because NASA and the government want to sent up this
> configuration that they do it.   It could be changed very easily
> to put up a 200,000 pound unmanned payload, but I can't think of
> any 200,000 pound payloads that anyone wants to put up that has
> the money to pay for it.

NASA's Marshall Space Flight Center has studied using the Shuttle stack with a
cargo pod with 2 or 3 main engines on it.  Its called the Shuttle C.
The cargo pod has minimal thrusters and a couple of General Purpose Computers
to control the system.  The system would use shuttle main engines that have
exceeded their man-rated life span.  I beleive the shuttle engines are to be
used for 10 launches before being replaced.  The shuttle C cargo pod would
be non recoverable and the use of the main engines would be their last flight.


>
> All of the dreams about manned travel to the moon and planets
> is great, but we can't all go.
>
> Joe Fischer       [e-mail]

Start saving your pennies now, One day maybe the National Areospace plane will
make space accessable.

--

Mike Kent -      Lockheed Engineering and Sciences Company at NASA JSC
        2400 NASA Rd One, Houston, TX 77058 [phone]
        [e-mail]

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

Date: 15 May 91 07:50:19 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] writes:
>
>>now there's an incredible argument: they f*cked up once so never
>>listen to them again. I'm convinced-there will never be an effective
>>winged spacecraft cause we tried once and failed. there will never
>>be a cheap launcher cause we tried once and failed.
>
>Let me try again with a less subtle arguement. The Shuttle failed
>for a number of reasons (pick your favorite). These all tract back
>to problems in the way systems like the Shuttle and ALS are developed.
>If these systemic problems are not identified and resolved then there
>is no reason to think that the next development project will be any
>different.
>
>Now, tell me just what problems have been identified? How have those
>problems been fixed? If nothing has changed, why should ALS be any
>different from the Shuttle?

The Navy has the example of Rickover, NASA has the example of Von Braun,
Lockheed has the example of Kelly Johnson. If they plan to put a strong
individual in charge of the program with a clear vision of where he wants
the program to go, they will succeed. If they try to design their camel
by committee, like with the Shuttle, and with constantly changing budgets,
like with Fred, they will likely fail.

Gary

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

End of SPACE Digest V13 #562
*******************