Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_7/V13_715.TXT

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Subject: SPACE Digest V13 #715

SPACE Digest                                     Volume 13 : Issue 715

Today's Topics:
           register Gabriel C. Lopez Walle
      CRAF penetrator (was Re: Chapman/Lowery Amendment)
            Re: RFD:  talk.politics.space
         Re: INFO: Clandestine Mars Observer Launch??
           Re: ASRM (Was: Re: More on Freedom Vote)
         Re: INFO: Clandestine Mars Observer Launch??
            Re: Beanstalk analysis reprise
            Re: orbiter production
         Re: INFO: Clandestine Mars Observer Launch??

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
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----------------------------------------------------------------------

Date: Fri, 7 Jun 91 17:21:57 GMT
From: [e-mail] (Gabriel C. Lopez Walle)
Subject: register Gabriel C. Lopez Walle

register Gabriel C. Lopez Walle

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

Date: 6 Jun 91 17:23:07 GMT
From: [e-mail]  (Jonathan Leech)
Subject: CRAF penetrator (was Re: Chapman/Lowery Amendment)

In article <[e-mail]> [e-mail] (Jim Bowery) writes:
>I brought up the possibility of reintroducing the penetrator to
>CRAF if it is delayed.  Again, no committment was made, but the
>possibility will be looked into.  I'm waiting for call-back.

    As the CRAF penetrator was removed for budgetary reasons, and the
cost of the mission will almost certainly go *up* if it's delayed,
this doesn't seem likely (nice idea, though).

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

Date: 6 Jun 91 17:20:36 GMT
From: [e-mail]  (Jonathan Leech)
Subject: Re: RFD:  talk.politics.space

In article <[e-mail]> [e-mail] (Ian Taylor) writes:
>BTW I think that it not a good basis to start a new newsgroup simply
>because some people are not interested in certain aspects of the discussion.
>eg I am not particularly interested in NASA prediction bulletins, so why not
>sci.space.nasa.prediction.bulletins?

    Actually, that makes a certain amount of sense.  Given the wide
variety of information-only postings to sci.space, sci.space.shuttle,
and sci.astro, collecting them someplace apart from the discussions
might be useful (sci.space.announce?)

    One problem with proposals for breaking down sci.space into more
discussion oriented groups is that there are least two large gateways
- BITNET SPACE-L and Internet SPACE Digest - into sci.space, and those
groups would probably continue to feed material into sci.space rather
than the appropriate subgroup.

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

Date: 7 Jun 91 17:30:04 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!mips!pacbell.com!iggy.GW.Vitalink.COM!widener!netnews.upenn.edu!uofs!vulture.cs.uofs.edu![e-mail]  (Bill Gunshannon)
Subject: Re: INFO: Clandestine Mars Observer Launch??

In article <[e-mail]>, [e-mail] (charles bridgeland) writes:
|> indeed.
|>     a big city, laid out in a nice rectangular grid, would signal the
|> presence of intelligent life just as well as a face, and be useful to boot.

Let's assume that some catastrophe killed off all the people living on earth (or
assuming we were further advanced, drove us out of this solar system.)  Catastrohpes
of this magnatude do happen, remember the dinosaurs.  How long after that do you
suppose our grand cities would continue to exist??  1 century?? 2 centuries??
How long do you think Mount Rushmore or Stone Mountain (GA) would be there??
Assuming all other signs of inteligent life vanished, what cause would be given
for the, by then, badly eroded faces on the side of a mountain in that un-inhabited
northern hemisphere??

bill

--

     Bill Gunshannon          |        If this statement wasn't here,
     [e-mail]   |  This space would be left intentionally blank
     [e-mail]    |         #include <std.disclaimer.h>

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

Date: 7 Jun 91 21:54:14 GMT
From: orca!bambam![e-mail]  (Bob Pendleton)
Subject: Re: ASRM (Was: Re: More on Freedom Vote)

In article <[e-mail]>, [e-mail] (George William Herbert) writes:
> In article <[e-mail]> [e-mail] writes:
> >Killing the ASRM is NOT the same as killing the shuttle. The ASRM is
> >an all new replacement for the existing SRM. The main reason for
> >building the ASRM is to put Thiokol out of the SRM business. Secondary
> >reasons for building the ASRM are to bring the shuttles payload up to
> >spec and to put a big aerospace manufacturing plant in the back woods
> >of the Great State of Mississippi.
>
>     The main reason for building the ASRM is that the SRM, even the
> redesigned one, isn't very safe.  Pushing the payload up a bit is nice too.
> As for the claim of putting Thiokol out of business or putting a plant
> in the back woods of Missippi:

ASRM will be no safer than than the redesigned SRM. Bet on it.

>     A. Thiokol could have bid on the ASRM; they had a design, and it was
> technically OK from what I saw, but they wanted out of the business.

Ok, it took me 5 minutes to stop laughing. But I'm OK now.  I going to
try to be nice, because you don't deserve a flame. But, you really
don't know what is going on.

You are assuming that Thiokol wants to just give away millions and
millions of dollars of business. They want to eat the cost of all
those buildings, all that tooling, and lay off all those people.
Right.

I know people who work at Thiokol, I eat dinner with them once a month
or so at AIAA councel meetings. The reason they didn't bid is because
they couldn't win. A bid costs many millions of dollars. Why waste
millions of dollars? Especially when Spacey Jake Garn the senator from
Utah is in a position to make sure that the yellow creek facility
never produces a single motor?

And if there is no ASRM, then Thiokol get to keep the business.


>     B. Mississipi is no worse a place to build rocket engines than Utah.
> If the motor has to be shipped over 5 miles, it's pretty much the same set
> of problems (though more cost due to per-mile costs).

From a technical point of view, and a pork point of view, you are
right. But what about from a human point of view?

Hercules Aerospace, the OTHER big solid rocket motor manufacturer here
in Utah has been laying off people left and right this last year. The
only Solid rocket propulsion jobs around are in yellow creek. I know a
bunch of Hercules, and ex-Hercules, folks and I've talked to a lot of
them who have interviewed with Aerojet for jobs in yellow creek.

People tend to be pretty happy about working for Aerojet until they go
for a plant interview. Then they see that if they move to yellow creek
and the ASRM doesn't get built they will have to just file bankruptcy
and walk away from any homes they might there.

In other words they are having a hard time hiring people to even go to
work in yellow creek.

>
> -george william herbert
> [e-mail]

--
              Bob Pendleton, speaking only for myself.
   [e-mail] or decwrl!esunix!bpendlet or hellgate!esunix!bpendlet

                         Tools, not rules.

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

Date: 7 Jun 91 17:03:03 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!netnews.upenn.edu!uofs!vulture.cs.uofs.edu![e-mail]  (Bill Gunshannon)
Subject: Re: INFO: Clandestine Mars Observer Launch??

In article <[e-mail]>, [e-mail]
|>                                                       (Jim Burnes - 235-7444) writes:
|>
|> C'mon guys...I am not about to start a UFO bashing contest (partly
|> because something like that appears to exists), but there is a special
|> part of your brain that is dedicated to doing nothing but recognize
|> faces.  Anything that has 2 "eyes", 1 "mouth" and is round will

Well, that's a new one on me.  I wonder what part of the brain that is??
But, it's beside the point anyway.

|> be recognized as such.  Really...if someone wanted to send us a
|> message why didnt they just encode it in symbology like we did
|> on voyager.
|>

Were the natives of Easter island trying to send us a message when they left
behind all those faces??  Were the Egyptians trying to send us a message when
they constructed the Sphynx??
Has the idea occured to anyone that IF (I said if!!) the face on Mars really
turns out to be a face carved by some form of inteligent life, it may not have
any meaning to us at all???  The next time you walk thru a cemetary with afluent
people from the last century buried in it, try and figure out what they are
trying to tell you with all those cute little statues that adorn their gravestones.
Or better still, visit any of a thousand historical sites here in the US.  You
will find numerous statues of people you can't recognize.  And if there is no one
around to tell you, you will never figure out what they are trying to say with
that artifact.

Maybe we should wait til we know if it is real or not before we try and figure
out what it means.

As for the symbology on Voyager.  It is only going to be meaningful to another
humanoid with a basis in mathematics equivalent to us.  None humanoids would
not recognize the two human figures and everything else would be meaningless
even to large portions of the population of this planet, much less to aliens.

bill

--

     Bill Gunshannon          |        If this statement wasn't here,
     [e-mail]   |  This space would be left intentionally blank
     [e-mail]    |         #include <std.disclaimer.h>

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

Date: 7 Jun 91 03:15:00 GMT
From: hpcc05!hpcuhb!hpcuhe![e-mail]  (Bob Campbell)
Subject: Re: Beanstalk analysis reprise

>>     I get to play the devil's advocate again.

>I wish you'd find something you do well, and then do it.

>>I don't like to
>>destroy people's dreams, but a reality check is in order here.

>Don't flatter yourself.

Actually, he has brought up some good points.

>>Your calculations seem to be based on an airless earth, i.e a
>>good vacuum. Don't forget that we have an atmosphere.

>Beanstalks don't do work on the air, so air drag is not a
>major consideration.

All forces that act on the beanstalk must be taken into
consideration.  The drag is going to be different at various
levels, this is going to add multiple levels of problems.

>>     1) You've allowed for longitudinal forces. What about
>>perpendicular forces ? What happens when the beanstalk gets hit
>>by a 100 km/h (60 mph) wind ? How about a 250 km/h

>If the wind continues long enough, the beanstalk assumes a
>catenary curve rather than running upward in a straight line.
>Changing winds excite vibrations, which may have to be damped.

You are assuming that wind is much simpler than reality.  I am
interested in your rough calculations, but this cannot be discounted.
Damping would have to be added accross the stalk, weight would not
be insignificant.   If the bottom end is left free as you suggest,
then aren't we talking about skyhooks?  A true beanstalk would
experience increased stress due to the fixed end.

> Alternative:  trifurcate the beanstalk at a point high in
> the stratosphere.  Attach each third to a separate anchor,
> on the points of an equilateral triangle.  No matter which
> way the wind blows, it only moves tension from one part
> to another; it does not push the beanstalk as a whole.

This could work with two anchor points, but I think a stable orbit
with an equilateral configuration would only work if it was a single
(very large) anshor with triple tethers.

>>Can you supply some typical "Asurf" values...

>Depends how much you want to lift.  1 square inch @ 2MPSI
>working tension should be able to lift 100 Klbs.  The weight
>to be lifted is not something which can be determined a priori.

>> along with the taper as a function of height.

>I posted all the mathematics required to do that.  Evaluate
>the taper integral for some endpoint other than geosync.
>I assume you still want the bottom to be on terra firma,
>so the 6380 km lower limit for the integration stands.

>You lose two points for not having the wits to know the
>answer was in your hand.

Or maybe he didn't want to recreate work that you should have
already done.  That at least would be complimenting you by
assuming you have done the work properly.

>>     2) Since a geosynchronous orbit sits on the equator, you
>>won't have to worry about icing... *AT SEA LEVEL*. At higher
>>elevations in the atmosphere it will be a worry in two ways.
>>Heavy icing will strain the beanstalk by sheer weight alone.
>>Icing will also increase the cross-section that wind loading
>>works on.

>Any flex in the beanstalk, or vehicles moving up and down,
>will cause it to shed ice.  Also, it can be heated electrically
>if icing is a difficulty.

Not true.  Flexing may be great for the total while being rather
small at any given section.  Ice is a major problem.

>>     3) Surface temperatures at the equator can hit 40C to 50C.
>>You can expect -40C to -50C up in the atmosphere, and some
>>utterly farcical values (both hot and cold) in the vacuum of
>>space. How will your materials react to this gradient ? How will
>>the outer-space portion of the beanstalk react to extreme diurnal
>>cycles (day/night) in a vacuum ?

>You are trying to tell me that a 100 C temperature difference
>between two parts of a very narrow structure some kilometers
>distant is going to cause problems with differential expansion?
><<Ron rolls on the floor laughing>>

>Graphite, aluminum, Mylar, and many other materials have no
>problems whatsoever with the "extreme diurnal cycles".

There are many factors that would tend to increase fatigue in the
stalk.  Materials science has its work cut out for it.  The stalk
has to perform well over a wide range of conditions at the same time.
The stalk could not be made of any of the materials you cited.

---------------------------------------------------------------------------
Bob Campbell                Some times I wish that I could stop you from
[e-mail]    talking, when I hear the silly things you say.
Hewlett Packard                                    - Elvis Costello

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

Date: 8 Jun 91 03:48:45 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: orbiter production

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>>Shuttle being able to launch people into orbit is certainly a very unique
>>capability when compared to Titan IV.
>
>Nope. Lots of people have gone up on Titans.

There is, however, no capability to send them up on Titans today.  One
could probably be developed easily enough, but it *does not exist today*.
Killing a working system before its replacement was even flying, much less
proven viable, was a disastrous mistake twenty years ago, and I'm afraid
this is starting to look like a repetition.
--
"We're thinking about upgrading from    | Henry Spencer @ U of Toronto Zoology
SunOS 4.1.1 to SunOS 3.5."              |  [e-mail]  utzoo!henry

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

Date: 8 Jun 91 04:12:09 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!mips!ptimtc!rdmei!icspub!astemgw!kuis!rins![e-mail]  (will)
Subject: Re: INFO: Clandestine Mars Observer Launch??

In article <[e-mail]>, [e-mail] (Bill Gunshannon) writes:
>Were the natives of Easter island trying to send us a message when they left
>behind all those faces??  Were the Egyptians trying to send us a message when
>they constructed the Sphynx??
>

    the sphinx is a natural phenomenon in the desserts of Egypt.  In a paper
    I read a couple of months ago (I forgot the name, but it is findable
    if you want to see it) it was stated that the great sphinx was a natural
    phenomenon that was recarved to the likeness of some great person of
    that time.  I don't remember exactly remember why it was done, but if
    there is interest in it.  I'll zap it on my scanner and post it for all
    to see.

    Also, as a side note:  I think that that face looks more like a monkey.
    So my guess is that mars must have been the "Planet of the Apes". Ha,
    Ha, Ha.  So much for intelligent life, since we now know that Apes on
    this planet are only as smart as our best CEO's and government leaders.
    Both of which have proven their stupidity over and over. He, He, He....


                            Will.....

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

End of SPACE Digest V13 #715
*******************