Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_2/V16NO230.TXT

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Date: Sat, 27 Feb 93 05:02:05
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #230
To: Space Digest Readers
Precedence: bulk


Space Digest                Sat, 27 Feb 93       Volume 16 : Issue 230

Today's Topics:
                             Anon posters
                  Beamed power transmission on Mars?
                        Fred and congress' job
                       Nobody cares about Fred?
                    Opening up Space to everyone!
                         Price for meteorites
    Reliable Source says Freedom Dead, Freedom II to be developed
software engineering vs. civil engineering (wasRe: Nobody cares about Fred?) (2 msgs)
           SSF Resupply (Was Re: Nobody cares about Fred?)
                        TOPEX Press Conference
                      Water resupply for SSF (?)

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Wed, 24 Feb 1993 18:44:30 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Anon posters
Newsgroups: sci.space

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


>>Use a kill file, let it all continue unchecked and the problem WILL get
>>worse.  We need to deal with it now, not stick our collective heads in
>>the sand.

>If a bonehead post drops onto usenet, and nobody reads it, does it make
>a noise?  :-)

Yep; hear that whirring sound?  That's your connection and disk drive
eating up resources.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 24 Feb 93 21:42:24 GMT
From: Henry A Worth <[e-mail]>
Subject: Beamed power transmission on Mars?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Frank Crary) writes:
> In article <[e-mail]> [e-mail] writes:
> >   I will express the opinion that this is not a practical idea. First, since
> >Mars has little atmosphere, an orbiting receiver will not be all that much more
> >efficient than solar cells on the ground (or on a rover, etc.). Nothing to be
> >gained by being in orbit, except maybe size.
>
> Actually, the atmosphere isn't the only problem with ground-based solar
> power: There is a horizon, which blocks sunlight about 50% of the time;
> there are dust stroms (which very effectively block sunlight and cover
> surfaces); there is gravity which increases structural weight;
> there is the planet's rotation, which requires a ~15 deg/hour tracking
> rate, to remain pointed at the sun. Also, there are transportation
> problems: It's easier to leave a power system on obrit, instead
> of fitting it into a lander, sending it to the surface and
> assembling it there.
>

   How much would a dust storm attenuate a microwave beam (I have a vague
memory that it's not much, at least at some frequencies)?

   An additional big advantage for beamed power is that if you have multiple
transmitters, individual work parties could be tracked and provided reliable
'round-the-clock power. With some point-of-use storage capability, time-slice
multiplexing of the power feed could be used as well.

   You could even vary flux to match activity. Transmitting at a higher
flux when personnel are in shielded vehicles and on the move (just when
you have highest demand! -- hey, microwave heated, hot gas blimps!, is the
Martian atomosphere dense enough?) and during rest periods to recharge
batteries. When personnel are out and about, the flux could be lowered
or the feed completly turned off if suit sheilding is inadequate or
in situations where scientific instrumentation required low noise. In
general, mining, manufacturing, and construction equipment could be fed
at a higher flux as well, as limited personnel and the environment would
demand that this sort of activity be somewhat automated and/or remotely
operated and maintained.

   It's really a shame certain parties rejected beamed power on Earth as
unsafe without any real study or basis in fact, simply on the basis of
technophobia, while at the same time turning a blind eye toward the very
significant, and quite possibly greater, negative impacts of existing
power sources (better the devil you know then the angel you don't?).

--
Henry Worth
No, I don't speak for Amdahl... I'm not even sure I speak for myself.

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

Date: Wed, 24 Feb 1993 18:53:35 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Fred and congress' job
Newsgroups: sci.space

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

>You listened to me :-)  And, if you'll continue your perusal of the document
>mentioned above, you will also notice the tenth amendment, which limits the
>powers of congress to those enumerated within the document.

Yes, but your problem seems to be an incorrect or inadequate
definition of 'powers'.  And you can hardly know how far I 'listened';
and I have to tell you that it wasn't all that far.

>If you'd like some info on what the Libertarians are doing, locally and
>nationally to put a stop to these kind of immoral and impractical legal
>situations, using the legal system istelf, drop me a line.

No thanks.  I'm not interested in impractical or unworkable
'solutions'.

>Aaand, on a related note....

>I'm a little hazy on the legal picture, but I've got an inkling that since
>the fed agencies are considered part of the executive, that Prez. Clinton
>can do what he damn well pleases (notwithstanding politics) WRT fred, etc.

>Is this so?

He can do anything he wants -- right up until the point where it costs
money.  The Executive Branch is allowed to 'execute', but not to
authorize spending.  That takes legislation (guess who does that).

So, if President Clinton wants to build Fred (I wish we'd find a
different name for that -- makes me depressed when people say that
nobody cares about Fred ;-)), he can build it as long as he can build
it for free.  If he wants to spend tax money on it, Congress has to
authorize it.


--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: Wed, 24 Feb 1993 18:47:28 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Nobody cares about Fred?
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Mary Shafer) writes:

>On the other hand, if we built buildings the way we write software,
>the first woodpecker to come along would have destroyed civilization.

Well, *some* of us try not to write it like that anymore.  That's the
basic difference between 'software engineer' and 'programmer'.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: Wed, 24 Feb 1993 21:49:57 GMT
From: Henry Spencer <[e-mail]>
Subject: Opening up Space to everyone!
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Marvin Batty) writes:
>... Why no disabled people in space? If payload weight is all
>important, and legs (for instance) are not terribly useful in a low-grav
>environment...

The idea that legs are not terribly useful in free fall is one of those
superficially-plausible ideas suggested in science fiction that turned
out to be false.  They're quite important as anchors even though they
don't get much use as supports.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360.                    |  [e-mail]  utzoo!henry

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

Date: 24 Feb 93 20:16:19 GMT
From: "Pat R. Brown" <[e-mail]>
Subject: Price for meteorites
Newsgroups: sci.space,sci.astro

I would be interested in helping to determine the authenticity of a
suspected meteorite. Please send E-mail.

Regards,
Pat Brown

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

Date: 24 Feb 93 21:59:24 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Reliable Source says Freedom Dead, Freedom II to be developed
Newsgroups: sci.space

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

>>But Dennis, this is pretty much what NASA planned to do with Freedom
>>before the micromanagers in Congress insisted on greater integration
>>to minimize this problem. NASA disagreed saying on orbit instalation
>>wasn't a problem.

>This is what was scaled way back by having the truss built in larger
>pieces on the ground and then launched in the cargo bay.

Exactly. NASA said the redesign wasn't needed and Congress mandated it
because they didn't agree. Again Dennis you find yourself in agreement
with Congress and disagreeing with NASA. Good job.

>This is also the
>case with the refueling that has been talked about here. They are simply
>changing them out instead of doing all of the on orbit work to refuel.  In
>addition, the Resupply module is also a quick changout item instead of
>having astronauts work to bring new supplies in.

Um... the Russians refuel in orbit with zero eva or even astronaut time
spent. It is done with an automatic system.

Changing a thruster module will indeed take quite a bit of astronaut
time both in the Shuttle and on Fred. If you where concerned with reducing
person hours for maintenance (thus freeing up valuable astronaut time for
experiments) you would oppose the present system. That is, assuming you
agree that we can develop a system as good as the Russian system.

Bottom line Dennis is the things you think save EVA time actually cost
more.

>With an ET design you have none of the above with the added problems of
>completely having to build up the interior from scratch.

So it takes a few years. Big deal. A minor issue compared with the years
and years Fred has taken and will take to achieve ANY operational capability.

At any rate, these are not problems. If you examine the SSI External Tank
Study you will find lots of alternatives which solve these problems for
far less than we are spending now.

>>Which is why the growth in logistics shuttle flights was called 'alarming'
>>in an internal NASA briefing in early 89.

>That alarm was silenced during the design of station three years ago.

Granted but it was solved by Congress when they mandated the 89 redesign
over the objections of Freedom managers. I'm gratified to see you agreeing
with Congress on this Dennis.

>To bring this up now that the problem has been largely solved is meaningless.

Not quite. You see, the problems with Freedom by and large aren't technical,
they're cultural.

I know I have called NASA managers incompetent in the past but that
isn't quite the correct word. The real problem is that these people
work in an environment where the people with responsibility have no
authority and the people with authority don't care if anything ever
gets built (so long as funding continues). Each center wants to grab
whatever they can and stop the other centers from getting anything.

This is why McDac Space Systems is $1 billion over budget on Fred yet
is performing awesomly on DCX. Nobody could ever expect a system like
this to ever work.

That culture still exist Dennis and IT is the problem.

>I will be meeting with some sources in the next few days that are working
>on plans to save about 2-5 billion dollars over the life of station in...

Dime a dozen Dennis. Hell, I have friends at the Reston Program office
who do that to amuse themselves on coffee breaks. Anybody who thinks
a little about it can save $20 billion or so in life cycle costs without
breaking a sweat.

Getting the change implemented, THAT'S the hard part.

  Allen

--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------111 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: Wed, 24 Feb 1993 18:43:41 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: software engineering vs. civil engineering (wasRe: Nobody cares about Fred?)
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Spiros Triantafyllopoulos) writes:

>In article <[e-mail]> [e-mail] (fred j mccall 575-3539) writes:
>>>Software engineering yahhh... Kinda like "military intelligence" hmmm?
>>
>>Yeah, sure.  Of course, you probably also want to say that the Tacoma
>>Narrows bridge was a *software* failure, too.  So tell me again how
>>there's no such thing as software engineering because it isn't
>>predictable and well understood like 'real' engineering -- like, say,
>>bridge design and construction . . .

>Perhaps I can shed some light, having the fortune (?) of being both a
>civil and a software engineer, college educated in both. (gave up
>civil years ago, no $ in Greece at the time...)

>One bridge collapsing while thousands of bridges stay put is not an indicator
>of bridge design in general. A good bridge (or building) designer can factor
>in ALL known things that will happen to the bridge. Software IS used for
>the analysis phase (solid modeling, materials, simulations).

>Building a bridge basically uses principles that are commonly understood,
>are taught everywhere the same way (tensile strength of steel is the same
>in China as in Greece...). Ditto for requirements analysis, i.e. so much
>load, so much wind, etc. Soil mechanics also; materials also; And,
>frankly speaking, it is *feasible* that anyone can open up a book, read
>up, and design a bridge that WON'T fail. The principles are in the book,
>and building requirements/regulations/material properties provide quite a
>bit of safety factors built in. There may be material differences (concrete
>vs. steel) but by and large no major problems exist.

>Software, on the other hand, is unpredictable by nature. Ask 10 software
>engineers to design the same problem and you'll get 10 drastically different
>answers;

Not exactly true; and of course, this doesn't happen with 'real'
things -- well, maybe it does, and one engineer will design a
cantilever bridge, another a suspension bridge, etc., all of which are
designed to cross from one side of something to the other.

>software can't be proven correct; bridges can.

Well, that's not specifically true, either.  The problem is that
software is usually too complex to prove in anything like finite time.
Of course, this can happen with bridges as well, if you get some
interaction or effect that isn't anticipated by the designer; remember
Tacoma Narrows?

>Rarely, if ever,
>bridge designers change the design or get 100 new pages of requirements...
>The software world thrives on such things.

Well, that's more a problem with people *other* than software
engineering (like the management/hardware engineer idea that software
is 'easy to change' while hardware isn't, etc.).  The same thing
*could* happen to hardware types, but typically doesn't.

>And, quite interestingly,

>nobody I know has ever written a book that can teach anyone how to write
>software in a concise manner;

This starts to sound like, "It's hard, so it can't be engineering."
Is it your position that there is no such field as electrical
engineering, also?  When you start slapping a few million features
onto a 200 mil piece of real estate, that's just a bit complex, too.
And I've never seen a book that can teach anyone to implement a CISC
chip of that complexity in a concise manner, either.

>If I choose a material or method to use in
>a bridge, any fellow bridge engineer will see it and realize why I did
>it (i.e. prestressed concrete vs. poured concrete). In software,
>this is not very realistic given the complex software products people
>produce.

You *are* saying that if it's complex, it can't be engineering!  Well,
that elminates just about everything but civil engineering from the
field.  No more electrical engineers; no more aeronautical engineers
(hey, if it was all provable, we wouldn't need test pilots, now would
we?), no more engineering in anything more complicated than stacking
up blocks, I guess.

>Software is more of an 'inner' product. There are many aspects of the
>software development process that can be handled thru normal
>engineering procedures, but there will always be the little bit of
>'art' that the individual programmer will add. There are cases that a
>programmer will implement the same thing in 10 different ways
>depending on mood. A bridge engineer *won't*.

>If I were to compare software engineering to another field, it'd only be
>architecture. Not engineering.

Spoken like a 'real' hardware engineer; which I guess explains why
some hardware engineers write such poor software.

>To give an even better quote, "Engineering is to Software Engineering what
>Fluid Mechanics is to Plumbing".

Great quote; pity you didn't try for something just a touch more
*accurate*.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

From: Dillon Pyron <[e-mail]>
Subject: software engineering vs. civil engineering (wasRe: Nobody cares about Fred?)
Newsgroups: sci.space

Date: Wed, 24 Feb 1993 19:44:43 GMT
Source-Info:  Sender is really [e-mail]
Source-Info:  Sender is really [e-mail]


In article <[e-mail]>, [e-mail] (fred j mccall 575-3539) writes:
>In <[e-mail]> [e-mail] (Spiros Triantafyllopoulos) writes:
>>In article <[e-mail]> [e-mail] (fred j mccall 575-3539) writes:
>>>>Software engineering yahhh... Kinda like "military intelligence" hmmm?

  [ lots of discussion left out, find it and read it]

>>If I were to compare software engineering to another field, it'd only be
>>architecture. Not engineering.
>
>Spoken like a 'real' hardware engineer; which I guess explains why
>some hardware engineers write such poor software.

One of my college friends (an architect) said that the hard part was the
desgin, an <sexist vulgarity> could build it.  Same thing with software
engineering.  So, I take the above comment as a compliment :-)

>
>>To give an even better quote, "Engineering is to Software Engineering what
>>Fluid Mechanics is to Plumbing".
>
>Great quote; pity you didn't try for something just a touch more
>*accurate*.

When I was in school, years ago, the science people detested the term "Computer
Science".  Now the engineering people hate "Software Engineering".  Since
computer art is already taken, I think we're left "Computer Magic".

But, as we all know by now, SSF has nothing to do with science, engineering or
computers.  It's all politics!
>
>[e-mail] - I don't speak for others and they don't speak for me.
Are you at SK or MK?
>
--
Dillon Pyron                      | The opinions expressed are those of the
TI/DSEG Lewisville VAX Support    | sender unless otherwise stated.
[phone] (when I'm here)     |
[phone] (when I'm home)     |No people gave up their rights all at once.
[e-mail]          |Preserve the Bill of Rights.
PADI DM-54909                     |Protect the Second Amendment.

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

Date: Wed, 24 Feb 1993 18:57:35 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space

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

>In article <[e-mail]>, [e-mail] (fred j mccall 575-3539) writes...
>>In <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:
>>

>>And if the Shuttle is grounded and the station is forced into
>>free-drift for lack of replacement thruster modules (which is the same
>>thing as saying that it ran out of fuel), then where are you?  It all
>>comes down to just how much money and opportunity cost is a small
>>incremental change in safety worth.  It is this failure at rational
>>risk analysis that has earned parts of NASA the poor reputation for
>>performance and cost effectiveness that they have.
>>

>The above is an opinion and should not be considered by the reader as
>gospel.  What about Titan IV ? Admittedly Titan IV's record is not
>stellar, but in the event of a problem the Air Force has 41 of them and
>they could be used in the event of Shuttle stand down due to disaster.

Uh, did you read the whole thread?  The argument I was responding to
was why this modular thruster replacement is 'safer' and 'better' than
refueling them in situ, with my contention being that refueling means
lifting less weight.  I was answered by, "But what if the Shuttle has
to stand down.  Then where are you?"  My point was that you are in
exactly the same place that you are with the replaceable thruster
design.

>Also the Station is primarily gravity gradient stabilized in order to
>preserve the microgravity environment. There could be many methods
>implemented to help reduce fuel use in case of trouble.

>In addition, it is my understanding that the primary reason for the
>Fuel on SSF is not for attitude control but for reboost. Now certainly
>they could live without reboost for a few months or even a year or two.

>Quit making mountains out of molehills. Just because you have not thought
>of the solution or you have not read it in Space News or seen it on
>Usnet does not mean that contingencies do not exist.

It wasn't my mountain.

>>--
>>"Insisting on perfect safety is for people who don't have the balls to live
>> in the real world."   -- Mary Shafer, NASA Ames Dryden
>>------------------------------------------------------------------------------
>>[e-mail] - I don't speak for others and they don't speak for me.

>You really ought to read the above statement by Mary that you append on your
>messages.

And you really ought to get a clue, Dennis.  While you're out shopping
for that, perhaps you can get a point as well, because your whole note
here seems to not have the slightest idea what it's talking about.
Given that, I'm not sure just what you think you're talking about with
your last snotty remark, either.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 24 Feb 1993 22:03 UT
From: Ron Baalke <[e-mail]>
Subject: TOPEX Press Conference
Newsgroups: sci.space,sci.geo.meteorology

Brian Dunbar
Headquarters, Washington, D.C.
(Phone:  [phone])                              Feb. 24, 1993

Bob MacMillin
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone:  [phone])

N93-08:  NOTE TO EDITORS

NASA TO BRIEF PRESS ON TOPEX/POSEIDON MISSION

    New findings on the El Nino ocean current will be among topics
discussed at a press conference on the TOPEX/Poseidon satellite mission on
Friday, Feb. 26, at 1 p.m. EST, in the von Karman Auditorium at NASA's Jet
Propulsion Laboratory, Pasadena, Calif.

    Scientists will discuss initial results from the U.S.-French
TOPEX/Poseidon satellite, which was launched Aug. 10, 1992, to map
circulation of the world's oceans and study the oceans' role in climate.  The
press conference comes at the end of a week-long conference attended by
more than 150 TOPEX/Poseidon scientists and oceanographers from around
the world.

     Participants will include Charles Yamarone Jr., JPL Project Manager; Dr.
Lee-Lueng Fu, JPL Project Scientist; Dr. William Patzert, NASA Program
Scientist; Michel Dorrer, French Project Manager; Michel Lefebvre, French
Project Scientist; Jean-Francois Minster of the Centre National d'Etudes
Spatiales, Toulouse, France; and James Mitchell of the Naval Oceanographic
and Atmospheric Research Laboratory in Mississippi.

    They will present results of the mission's verification phase, including
the first map of ocean topography and a video animation of the global ocean
current systems mapped by TOPEX/Poseidon.

         The press conference will be broadcast live on NASA Select television
with two-way audio from other NASA centers.  NASA Select is carried on
Satcom F2R, transponder 13, 72 degrees west longitude, C-band, frequency
3960 MHz, audio subcarrier 6.8 MHz, vertical polarization.

                              -end-
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | If you don't stand for
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/  |_|/       |_____|/                     | for anything.

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

Date: 25 Feb 93 00:11:44 GMT
From: Josh Hopkins <[e-mail]>
Subject: Water resupply for SSF (?)
Newsgroups: sci.space

[e-mail] (BAIRD) writes:


>    Well, a thought accured to me after reading a number of the posts here
>that dealt with the resupply of the space station (Fred or Son/Daughter of Fred)
>....Everyone is complaining about the cost of the space station's resupply
>through the shuttle or HOPE or Hermes.  WHy not just NOT use these vehiciles?
>I have heard of a number of proposals to drag ice from the outer system and
>refine it in orbit or get it from the asteriod belt.  Using a set of robotic
>systems, using either electric propulsion(EP) or light sails(LS), in conjunction
>with a few robotic mining platforms shouldn't it be feasible to resupply the
>space station using either the belt or the outer planets' moons?

This is a good idea as a concept.  However, it gives me visions of equiping
Marco Polo's horses with CAD designed composite horseshoes.  If we could do
all this stuff we wouldn't be worried about refueling Freedom.

--
Josh Hopkins                                          [e-mail]

    You only live once.  But if you live it right, once is enough.
            In memoria, WDH

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

End of Space Digest Volume 16 : Issue 230
------------------------------