Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_3/V13_325.TXT

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Subject: SPACE Digest V13 #325

SPACE Digest                                     Volume 13 : Issue 325

Today's Topics:
            Re: railguns,superguns
             Magnetic projectile launcher
                Re: "Follies"
              Re: MANY QUESTIONS
             Re: I want to go to orbit...
            Space shots on CDROM for AMIGA
              Re: More cost/lb. follies
  HST update during educator satellite video conference (Forwarded)
             Pay as you go/Go as you pay
              Re: JPL spacecraft

Administrivia:

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

Date: 27 Mar 91 04:12:14 GMT
From: rochester!sol![e-mail]  (Brian Yamauchi)
Subject: Re: railguns,superguns

In article <[e-mail]> [e-mail] (Chris Stanfield) writes:
>In article <[e-mail]> [e-mail] (Ian Stirling) writes:
>>Here in the UK there was a program on TV,about the iraqi supergun
>>affair ("petrochemical" pipes were actually bits of a massive gun
>>barrel) It talked about the scientist who concieved the
>>idea
>
>The scientist in question is Gerald Bull (who was murdered under as
>yet unexplained circumstances about a year ago).

According to PBS's Frontline, he was assassinated by the Mossad.
Evidently, it was a fairly elaborate operation, involving something
like 20 agents -- most monitoring his movements, and a few performing
the actual hit outside his apartment.

It's interesting to speculate about what would have happened if Bull
had successfully completely a gun with intercontinental or orbital
launch capability.

Of course, the gun would have been taken out as soon as it shelled Tel
Aviv (or Washington D.C.), but the even the temporary existence of
such a weapon might have been enough to spur some rather urgent
interest in the development of our own gun launchers.  Considering the
political windfall that SDI and smart weapons have gained from the
Gulf War, perhaps Sandia's coilgun and LLNL's light gas gun could have
gotten a boost from an operational Iraqi supergun.  I can see it now,
administration officials testifying to Congress about the dire
consequences of not closing the Supergun Gap...

It would have been ironic if Bull, by helping an enemy of the U.S.,
had been able to do more for space launch technology than he was ever
allowed to do when he worked from the U.S. and Canadian governments...
--
_______________________________________________________________________________

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

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

Date: Tue, 26 Mar 91 13:45:01 EST
From: "S.K. Whiteman" <[e-mail]>
Subject: Magnetic projectile launcher

In the March 1991 issue of NASA Tech Briefs on page 48 there is a
discription of a Superconducting magnetic projectile launcher.
Interesting technology 8-).

Sam
Indiana University - Purdue University at Fort Wayne
Fort Wayne, Indiana USA

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

Date: 26 Mar 91 08:19:54 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: "Follies"

In article <[e-mail]> [e-mail] ("Allen W. Sherzer") writes:
>
>Now figure 50 families today with two children and middle to upper income.
>At $100K each raised form liquidating their net worth we have $5M.

The average family net wealth in the U.S. (savings, house, car etc. minus
mortgage and other debts) is near $20K, not $100K, giving us a $1M budget.


>We need to
>lift ~750 pounds per family (figure 500 pounds for the people and another
>200 pounds for personal effects) for a total of 37.5K pounds.

For 200 people, and assuming ratios somewhat better than those of the Apollo
capsule and Shuttle cabin, figure in another 40,000 lb. for pressure
vessel, and 40,000 lb. for life support, bringing us to 117.5K pounds.


>This comes
>to $133/pound which is less than two orders from current prices to LEO.

This brings us to $1,000,000/117,500 = $8.51 per pound to our final
destination.


>Now they will need to get from LEO to the moon or some L point. However, with
>access to lunar resources which will be far cheaper so I figure it rounds off
>to under two order reduction.

Access to lunar resources at what price?  For this to be cheap requires
a very diverse, automated, efficient mining and manufacturing industry.
(And, BTW, the Moon cannot efficiently supply many required elements, so
we might as well use asteroids and comets, which are easier to get
to L-5 anyway).

The contemporary rule of thumb for transport cost is a factor of 4 to GEO
and spots like L-5 (the location of our proposed colony).  If our destination
is a planetary surface, the cost is rather higher. This brings our
requirement to $2.12/lb. to LEO, in order to get to L-5.

Unfortuneately, our family has spent all its money, and cannot afford to
buy a home at L-5.   If houses at L-5 cost half that of Earth (which also
requires mature space industry), we can split 50/50 between housing and
transportation costs, so that the price we really need is $1.06/lb. to LEO,
which is closest to 4 orders of magnitude below current launch costs.

If space industry is _extremely_ efficient and mature, and we can assume
all super-LEO costs (transportation, housing, etc.) to be zero, we can
use the $8.51 figure, about 3 orders of magnitude.

Chem rockets cannot provide even a one order of magnitude drop, but
tethers combined with suborbital airplane or laser launch, combined with
very cheap EML or gas gun freight costs for the inevitable industrial
"uploadings", can give us transportation for the Expansion Age.


>[Need infrastructure]

This is the most important point, that we need mature space mining
and manufacturing technologies.  This cannot be emphasized enough
(and gets lost in the cost/lb. obsessions).  Otherwise, space housing will
remain at 300,000 times the price of earth housing, not half or zero.
This issue is much more important for the Expansion Age than the launch
transportation problem, and helps provide a solution for it, via tethers
or other space-manufactured upper stages.


>....However, this can
>be provided for in the same way as all other large infrastructure jobs
>are done: the government pays for it in anticipation of enough activity later
>on to pay for it.

Cripes.  Much large infrastructure is _not_ done by the government, and
when it is it is _not_ a welfare handout to would-be colonists.
(Unless we are talking low-income housing, in which case we better throw
in another big factor of reduction....)


>ALS will not achieve an order of magnitude reduction in launch costs. In fact,
>I will bet money that it ends up MORE expensive than the Shuttle.

Sadly, this could be true; however the prospects for other cost/lb. ventures
are not significantly better.


>This program has got to be killed or we will accomplish
>nothing in the 90's.

I agree, and note that this reasoning applies to all $multi-billion
government chemical rocket programs.

There is room for incremental improvement of chemical rockets --
by _private industry_.  Only private industry can judge the true
limits of lauch costs.  Let government work on those technologies
that can provide the large, curve-changing breakthroughs.



--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 26 Mar 91 16:20:28 GMT
From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: MANY QUESTIONS

In article <[e-mail]> [e-mail] (Paul Blase) writes:
> HS> Putting the tank into orbit costs payload...
>
>Actually, from what I've read, it would actually ADD cargo capability.
>The shuttle now has to do a complex manuver to dump the tank...

You're 5+ years out of date.  They don't do that any more.
--
"[Some people] positively *wish* to     | Henry Spencer @ U of Toronto Zoology
believe ill of the modern world."-R.Peto|  [e-mail]  utzoo!henry

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

Date: 26 Mar 91 15:08:02 GMT
From: vsi1!teda![e-mail]  (Mike Ardai)
Subject: Re: I want to go to orbit...

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
-In article <[e-mail]> [e-mail] (Mark SOKOLOWSKI) writes:
->    What are the steps in order to build a reliable space-shuttle like
->spaceship in order to send myself to orbit for the summer holidays?
-
-First you need to locate a source of dilithium crystals.  You're not going
-to get off the ground without them.

That won't help.  Dilithium crystals are used for energy conversion in
warp drives.  You need either thrusters or low impulse drives until you
are well outside a planet's atmosphere...
/mike (visiting from the Cochrane Institure :-)



--
\|/  Michael L. Ardai   Teradyne EDA East
--- -------------------------------------------------------------------------
/|\  ...!sun!teda!ardai (preferred)  or [e-mail]

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

Date: 26 Mar 91 17:33:24 GMT
From: csus.edu!wuarchive!zaphod.mps.ohio-state.edu!usc!rpi!news-server.csri.toronto.edu!utgpu!watserv1!shine13![e-mail]  (Watshine - Extension Id)
Subject: Space shots on CDROM for AMIGA


    I am thinking of purchasing a CDROM player for my AMIGA computer, and am generally interested in puchasing the Voyager pictures (and others if they are
available) to view on my Amiga.  What stuff is available on CDROM from NASA, and does anyone know if these CDROMs could be read from an amiga compatible CDROM
drive (say XETEC, or CDTV).
    I've heard of the Voyager shots being in a format called VICAR.  Is
there a viewer available for the AMIGA computer?  Or is it just for the IBM.
Could someone port the viewer to the AMIGA?  I've also heard that some of the
CDROMs have pictures that are in condensed format.  Would I be able to
uncompress them on my AMIGA?

    I would appreciate any replies (mail would be ideal).

            Thanx!


                    Jason

--
 ---------------------------------------------------------------------------
Jason Trimble    PHONE [phone]            530A Rosemeadow CR.
1B CS EEE student at the University of Waterloo        Waterloo, Ont.
INTERNET: [e-mail]            N2T 2A1

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

Date: 26 Mar 91 21:07:25 GMT
From: isis!isis![e-mail]  (Glenn A. Serre)
Subject: Re: More cost/lb. follies


... Titan rockets
use chemical etching to get their tank walls thin enough....

Actually, Titan rockets only use chemical etching (chem-milling) on the
tank domes (and other, similar parts).
The cylindrical sections are machine-milled.  It is my impression that
the chem-milling is only neccessary because the edges of the sections
have to be thicker so they can be welded.  The newer tank domes will be
machined ("spun") as one peice and so will not require chemical milling.

Also, I would like to point out that Titan rockets WOULD fly if the domes
weren't chem-milled, they just wouldn't lift as much payload.

--

--Glenn Serre
[e-mail]
--

--Glenn Serre
[e-mail]

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

Date: 27 Mar 91 01:38:19 GMT
From: [e-mail]  (Peter E. Yee)
Subject: HST update during educator satellite video conference (Forwarded)

Terri Sindelar
Headquarters, Washington, D.C.
(Phone:  [phone])                          March 26, 1991


N91-23

EDITOR'S NOTE:
HST UPDATE DURING EDUCATOR SATELLITE VIDEO CONFERENCE


    On April 2, Dr. Ed Weiler, Program Scientist for the Hubble Space
Telescope (HST), will discuss the challenges encountered by the HST
team as well as discuss and show images of the excellent and unique
scientific findings.  The April 2 conference, the last in a series of four
educational video conferences conducted annually by NASA's
Educational Affairs Division, will be transmitted via a Westar IV satellite,
channel 19, from 2:30 to 4:00 p.m. EST.

    More than 30,000 educators in 50 states are expected to
participate in this program.  The 1-1/2 hour, interactive video conferences
are designed to update teachers on NASA programs, demonstrate
aerospace activities for classroom use and announce new programs,
products and activities available to classroom teachers.

    The satellite video conference series is produced by NASA's
Aerospace Education Services Project from Oklahoma State University
Telecommunications Center.

    To register for the series, interested teachers should write to NASA
Aerospace Education Services Project, Videoconference Site, 300 North
Cordell, Oklahoma State University, Stillwater, Okla., 74078-0422, or call
405/744-7015.  Registration is free and ensures that announcements,
publications and other materials for teacher-participants are received by
the school.  The 1991-92 series of educational video conferences will be
announced later this year.

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

Date: Tue, 26 Mar 91 09:23:38 PST
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
Subject: Pay as you go/Go as you pay


According to this week's (25-MAR-1991) AW&ST,  Richard Truly has banned the
phrase "pay as you go" from NASA's vocabulary.  "Truly believes it is hard
enough to garner sufficient funds when programs do have firm schedules,"
the article says.  However, in a letter last week endorsing the revised
space station, Vice President Dan Quayle wrote to Truly saying
"We will 'go-as-we-pay', be we must go."

_____________
Dale M. Greer, whose opinions are not to be confused with those of the
Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER
Separated at Birth?
"Those who secede will doom themselves to failure." -- M.I.Gorbachev
"If we do not succeed, then we run the risk of failure." -- J.D.Quayle

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

Date: 26 Mar 91 16:51:26 GMT
From: elroy.jpl.nasa.gov!jato!mars![e-mail]  (Ron Baalke)
Subject: Re: JPL spacecraft

In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>nasa.gov>
>Reply-To: [e-mail] (Nick Szabo)
>Organization: Sequent Computer Systems, Inc
>Lines: 19
>
>In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>
>>....JPL is the only one to send spacecraft to all of
>>the planets except Pluto.
>
>Not only that, but JPL has been _first_ to every planet, and their
>Explorer probe also discovered the Van Allen belts (without which discovery,
>we would have had some toasted astronauts).
>

I hate to disagree with you on this one, but Pioneer 10 made it to
Jupiter first, and Pioneer 11 was first at Saturn, paving the way for
Voyager 1 and 2.

      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

End of SPACE Digest V13 #325
*******************