Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_6/V13_616.TXT

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Subject: SPACE Digest V13 #616

SPACE Digest                                     Volume 13 : Issue 616

Today's Topics:
             Who gets free plane tickets?
        Info request about "The Spaceships of Ezekiel"
               Re: Saturn V and the ALS
                  Re: SR-71
            Extra Terrestrial Intelligence
 Stepping back, asking why? (was Re: Rational next station design...)
           Re: Who gets free plane tickets?
        Re: Terraforming Mars?  Why not Venus?
   Missing the point about tethers (was Re: SPACE Digest V13 #541)

Administrivia:

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Date: Tue, 21 May 91 10:44:09 PDT
From: [e-mail] (Jim Bowery)
To: crash![e-mail]
Subject: Who gets free plane tickets?

Those of us who aren't being paid by the government should have at
least as much say in our government as those who are, such as NASA
civil servants and their contractors at places like McDonnell Douglas.

This is especially true since we are the ones who are paying the bills.

That being the case, whenever a civil servant or contractor flies into
Washington D.C. to lobby for something like Space Station Fred, it is
only fair that the government also pay for at least one taxpaying
citizen to fly into Washington D.C. to lobby against something like
Space Station Fred.

This is actually unfair to the taxpayer because it presumes that the
guys flying in to lobby for Fred shouldn't simply be thrown in jail
for doing so -- which is in fact what should be done.

I urge you to contact your Congressional representative and ask that
they take one of two actions:

1) Either send you an airfare to Washington D.C. so that the anti-Fred
constituency can have equal time with the government paid pro-Fred
lobbyists.

OR

2) Track down all of the government paid pro-Fred lobbyists who have
flown in and throw the lot of the criminals in jail.
-----------------------------------------------------------------------------
Jim Bowery      619/295-3164               The Coalition for
PO Box 1981                                   Science and
La Jolla, CA 92038                             Commerce
-----------------------------------------------------------------------------

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

Date: 21 May 91 11:01:40 GMT
From: mcsun!corton!imag![e-mail]  (Philippe Schnoebelen)
Subject: Info request about "The Spaceships of Ezekiel"

I'm looking for any info that would allow me to assess the scientific value
of "The Spaceships of Ezekiel", a book written in 1974 by Josef F.
Blumrich.

Blumrich is a rocket scientist. Indeed, he has been chief of the system
layout branch of NASA (the book claims).  In the book, Blumrich shows how
the Bible contains information allowing to design a spaceship. While my
first reaction would be to blankly dismiss any such claims, I would like to
read any evaluation (by a specialist) of this work, e.g. in a book review
in a technical magazine devoted to aeronautics. [I am almost completely
ignorant of the field.]

More generally, any opinion is welcome on how to evaluate such a work.

Thanks in advance !

--PhS

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

Date: 21 May 91 05:29:01 GMT
From: eru!hagbard!sunic!mcsun!ukc!edcastle!aiai!aipna!cstr![e-mail]  (Richard Caley)
Subject: Re: Saturn V and the ALS

In article <[e-mail]> [e-mail] (Doug Mohney) writes:

dm> Besides, it's difficult for me to believe that hundreds of thousands
dm> of people would line up at Edwards AFB to watch the tin can land on a
dm> lakebed. :-) No romance.

#define romance slapstick_comedy

--
[e-mail]        Is it a brick, is it a bathtub, ...

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

Date: 23 May 91 20:44:52 GMT
From: coyote![e-mail]  (John Hughes)
Subject: Re: SR-71

In article <[e-mail]> [e-mail] (Duane P Mantick) writes:
>[e-mail] (Mary Shafer) writes:
>>Yes, I know where they'll operate from.  I know where two of them already
>>are.  I'm trying to come up with an experiment that uses them, since I
>>work in high speed flying qualities and there are some issues that need
>>to be addressed for the project I'm currently involved in.
>
>Hi Mary!
>
>Well, it isn't an experiment, but if you want to send one out here to the
>midwest, I *still* haven't seen one actually flying.  A nice pass down the
>flightline at the Dayton airshow would be dandy....
>
>:-)  :-)
>
>Duane
>(....or, as one of the pilots said after the XB-70's last flight, 'I'D
>do *almost* anything to keep it in the air....except pay for it myself....')

I'm not sure just how applicable this little story is to this newsgroup, but
it is one of my fondest memories:

Many years ago I was contracted by NASA to do some documentation for the
telemetry analysis equipment being used to test the X-29. As a result, I
had the pleasure of working with the folks at Dryden. Now, having the chance
to drool all over the X-29 was a treat in itself, but I was also hoping to see
one of the SR-71's that inhabit Edwards AFB on occasion. One day, as I was
driving along the almost arrow-straight stretch of road that leads into the
base, I was startled to the point of completely stopping the rental car by
an incredible roar. Nothing seemed to be wrong with the car, so I looked up
through the open top and saw the tail-end of an SR-71, going almost straight
up. For the next 30 minutes or so I sat mesmerized as the pilot proceeded
to do "touch-and-go's" with the plane, along with a couple of high-speed
circuits around the countryside. The pilot was a true pro, and the plane
looked like flying it was effortless (which, from what I understand, is
not exactly the case).

It was a sight I will never forget, and I am glad that these magnificent
machines will not end up in a 'museum' for a while. They are just too
amazing to mothball.


--
|     John M. Hughes      | "...unfolding in consciousness at the            |
| datalog.com!moondog!jmh | deliberate speed of pondering."  - Daniel Dennet |
| [e-mail]     |--------------------------------------------------|
| [e-mail] | P.O.Box 43305, Tucson, AZ 85733    602-624-8008  |

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

Date: 23 May 91 12:02:17 GMT
From: mcsun!hp4nl!sara5!hasara11![e-mail]
Subject: Extra Terrestrial Intelligence

Many arguments can be made for and against the idea that there is
life on planets in de Milky Way Galaxy besides on earth. If there
is (intelligent) life on other planets, would their technology be
ahead of us? How far? Would they have tried to contact us? Why?
Why not? I have posted questions like this on sci.astro recently
and some of the replies were:

(1) Why SHOULD they have tried to contact us? Space is BIG. Why
should they expend much efford searching every planet in the galaxy
for life? The first indication they'd get that something interesting
was happening on earth would be when they started picking up our
radio broadcasts about 100 years ago so anybody more that 100 light-
years from us hasn't had time to hear us and respond (Carl Hamlet)

(2) Why wasn't the entire galaxy colonized thousands of millions of
years ago? The time for a colonization wave to travel across the galaxy,
even with spacecraft traveling well below the speed of light, is only
a fraction of the age of the universe. Our solar system has apparently
not been colonized; we see no evidence of large scale engeneering in
the asteroid belt or on the moon, for example. (Paul F. Dietz)

(3) If any highly intelligent and advanced species is agressive enough
to wipe out all other species they would have done so. The beauty of
this idea is that you need only one species out of possibly billions

(4) Maybe highly intelligent species don't communicate much

(5) Maybe we're the only inhabited planet in the universe...

Any other comments on this would be greatly appreciated

Bjorn Bruinsma (Bitnet: a6014bb@HASARA11)

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

Date: 22 May 91 05:13:34 GMT
From: rochester![e-mail]  (Brian Yamauchi)
Subject: Stepping back, asking why? (was Re: Rational next station design...)

In article <[e-mail]> [e-mail] (Kieran A. Carroll) writes:
>In article <[e-mail]> [e-mail] writes:
>>
>>Instead of _assuming_ a design concept "space station", start with the
>>question: "what do space users need?"  The major space users being
>>defense, commerce (mostly communications), and exploration.

>You're going in the right direction...now, take one >little< step
>further back...

>Try asking the question, "What is our long-term reason for carrying out
>space exploration?" It's good for the soul for a space enthusiast to
>occasionally ask himself what the basic reason is that people should
>spend money on this stuff.

Good point -- now if you can take one more step back...

You can see that this consists of *two* separate questions:

1) Why do we (space enthusiasts) want to explore space?

2) How are we going to get other people (taxpayers, corporate
executives, or venture capitalists) to pay for it?

>Many people working on spaceflight subscribe to an unofficial
>goal, the expansion of human presence into the solar system and
>beyond. This is "The Dream" that keeps NASA employees at work despite
>low pay, lousy working conditions and a customer that doesn't really
>want what they have to sell. This goal has never been officially
>endorsed, however.

This -- the basic human drive for exploration, adventure, and new
frontiers -- answers question (1).  Whether it can also answer
question (2) depends on who are the "other people" who are going to
pay for it.

If they are business people, they are unlikely to find this
compelling.  The way to convince them is to show that you can make
money from space -- that may not be your ultimate goal, but it is
theirs.  Convince the private sector that space development can be
truly profitable, and not even the Luddites will be able to keep their
ventures on the planet.

If the "other people" are taxpayers, it depends.  If you could
convince the media to undertake a full-spectrum news/entertainment
campaign like the one they are currently putting on for
environmentalism -- but focused on the dream of creating a spacefaring
civilization instead of the nightmare of global eco-catastrophe --
then it might work.  Greenpeace changed from a lunatic fringe group
into a mainstream political powerhouse in less than a decade -- NSS
could do the same.  I predict that, by 2001, people will be as burned
out on greenies as they currently are on yuppies -- possibly
fortuitous timing to make space the "next big cause".

As to whether it would be better to pursue the private or governmental
route, I would prefer to pursue *both*.  (I'm sure you can pick up the
various pro/con arguments on any one of the many current flame-, er,
discussion threads.)
--
_______________________________________________________________________________

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

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

Date: 21 May 91 23:57:14 GMT
From: agate!stanford.edu!unixhub!slacvm![e-mail]  (Jon J Thaler)
Subject: Re: Who gets free plane tickets?

In article <[e-mail]>, [e-mail] (Jim Bowery)
says:
   [...lots of stuff deleted...]
>-----------------------------------------------------------------------------
>Jim Bowery      619/295-3164               The Coalition for
>PO Box 1981                                   Science and
>La Jolla, CA 92038                             Commerce
>-----------------------------------------------------------------------------

Just to clarify things...  Which axe are you grinding?

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

Date: 23 May 91 15:48:20 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!suned1!slced1![e-mail]  (Lloyd E Vancil)
Subject: Re: Terraforming Mars?  Why not Venus?

In article <[e-mail]> [e-mail] (Brian McCormick) writes:
>I agree.  The real issue is not to get rid of the sulfur, it is to
>cool off the planet.  If the planet is cooled off, the sulfuric
>acid will precipitate and fall to the surface where it will no doubt
>react with minerals present there.  IMHO, the same is true of the
>carbon dioxide in the atmosphere of Venus.  The Earth may well have
>just as much carbon dioxide as Venus.  Where is it?  Carbonate rocks.
>Cool off Venus, add water, wait a few thousand years, and Venus's
>carbon dioxide will probably end up in the same place.
>
>(Not that I think terraforming Venus is in any way a practical
>solution to any existing problem...  Contemplating terraforming
>is an interesting "what if?" exercise though.)

}end of excerpt

"The Snows of Venus"  - G. David Nordley - Analog May 1991
"Then came the project.  Mercury had provided the material for the sunshield,
magnetic ore hoppers riding electric launch rails past escape velocity and
breaking in the hundred kilometer tracks laid in trusswork across Venus L1."

Now there's a vision, a 20,000 km sunshield (umbrella) arranged with an optical
system to provide station keeping...  (huh? isn't that a little like the
cartoon sailbaot powered by an electric fan?  oh well SF right?)

--
 | suned1![e-mail] | * S.T.A.R.S.!   .       +      o       |
 | [e-mail]    | The Revolution has begun!   .     +    |
 | sun!suntzu!suned1!lev         | My Opinions are Mine mine mine hahahah!|

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

Date: 23 May 91 21:03:57 GMT
From: csus.edu!wuarchive!sdd.hp.com!caen!ox.com!fmsrl7![e-mail]  (Ron Carter)
Subject: Missing the point about tethers (was Re: SPACE Digest V13 #541)

In article <[e-mail]> [e-mail] (Walter Dnes) writes:
>     So we no longer burn a hydrogen-oxygen mixture in the shuttle's
>rockets... instead we react hydrogen & oxygen in a fuel cell to
>generate electricity to power the motor that reels/unreels the
>tether. I still fail to see the difference. Now, how do you get the
>hydrogen/oxygen up to the station ?

1.)    Only reeling in a tether requires energy.  Reeling a tether
    out *generates* energy.
2.)    Have you ever heard of solar cells?

>     Assuming that the station can maintain its structural
>integrity through several years of heavy-duty jolting to kick
>the shuttles out, *WHERE DOES THE ENERGY FOR THE "KICK" COME
>FROM* ? A magnetic-repulsion launcher would require electricity,
>which would take us back to fuel cells.

A 100-meter standoff is all that is required.  This can be done
using the Shuttle RCS system.  No kicking or electricity is needed.

>     The tether may or may not work once it's set up, but it begs
>a question that I haven't seen addressed before... *HOW DO YOU
>GET ALL THAT MATERIAL UP THERE IN THE FIRST PLACE* ??? Let's
>assume that the first tether is a 1-meter-thick cable 500km long.

What do you need a 1 meter thick cable for?  And why 500 km?
This tether is to lower a Shuttle from a space station, not
pick up sub-orbital payloads.  500 km puts the Shuttle somewhere
below the bottom of the deepest ocean trenches.

>Cross section = pi * r^2 = 3.14 m^2.

Have you not yet learned the difference between diameter and radius?
How pathetic.  I hope you aren't responsible for engineering design
anywhere; if you are, tell me where so I can avoid their products.

Let's try some more reasonable assumptions:

A 100,000 kg Shuttle orbiter is to be reeled out a distance of
200 km (120 miles) from a space station.  Assume the mass of the
space station is 400,000 kg, putting the Shuttle 160 km from the
center of mass at maximum extension.  The tidal+centrifugal
forces on the tether will be roughly:

(160 km * .004 m/sec^2/km * 1e5 kg ) = .64 m/sec^2 * 1e5 kg = 6.4e4 N.
Call it 15,000 lbs tension.

The yield strength of Kevlar 49 is 800,000 psi if memory serves,
and its density is about 1.7.  Using a working strength of 400,000
psi, the required cross-sectional area is .0375 in^2, or .24 cm^2.
The length is 2e2 km = 2e5 m = 2e7 cm.  Total volume is 4.8e6 cm^3,
or 4.8e3 liters.  Total mass is 8160 kg, or about 9 tons.  Add
some more for the reel, motor/generator, gear train, etc.  A
couple spare tethers are a good idea, in case one is hit by
space junk and severed, or tangled and must be cut loose.

>Let's get serious folks. How many shuttle flights is it going to
>take to get it all up ?!?!?!

I am quite serious, and you could ship several of these up in
one Shuttle or Titan IV shot.  I'd like to see you seriously
analyze something before posting, it would be refreshing.

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

End of SPACE Digest V13 #616
*******************