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Subject: SPACE Digest V9 #381

SPACE Digest                                      Volume 9 : Issue 381

Today's Topics:
              Space News Apr 18
  Commercial sounding rocket press briefing set April 21 (Forwarded)
                RE: Astrology
             Re: Rail-Guns and Asteroids
       Re: Unmanned shuttle advantages (was: Re: alien contact)
             Re: Rail-guns and Asteroids
         Re: U.S. vs Soviets (was Re: Alien contact)
           Re: Assaying likely asteroids from afar
             Re: failures and engineering
             Neville Shute's "Slide Rule"
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Date: 18 Apr 89 17:57:44 GMT
From: cfa!cfa250![e-mail]  (Jonathan McDowell)
Subject: Space News Apr 18

Jonathan's Space Report

Apr 18, 1989 (No. 12)

The Soyuz TM-7 crew are winding up their research program
on the Mir orbital station. Mir is to be abandoned while
a new crew is trained to repair the electrical power system.

The STS-30 mission is still scheduled for Apr 28.

The 23rd Raduga ('Rainbow') geostationary comsat was launched by Proton
from Baykonur on Apr 14. The satellite is used principally for Soviet government
and military communications.

Other news:

Kosmos-2016, launched on Apr 4, is a VMF (Soviet Navy) navigation satellite,
part of a system analogous to the USN Transit.

Kosmos-2017, launched on Apr 6, is a GRU spy satellite based on the Vostok
design. It is expected to land on Apr 20.

The SAGE (Stratospheric Aerosol and Gas Experiment) satellite
reentered on Apr 11. The NASA satellite was used in 1979-81 to study the ozone
layer as part of the Applications Explorer program.


---------------------------------------------------------------------------
(c) 1989 Jonathan McDowell, all rights reserved
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Date: 17 Apr 89 18:26:12 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Commercial sounding rocket press briefing set April 21 (Forwarded)

[Query:  Does anyone object to seeing NTEs?  Is there any interest in this
sort of material?  -PEY]

Jim Ball
Headquarters, Washington, D.C.                     April 17, 1989


N89-34:  COMMERCIAL SOUNDING ROCKET PRESS BRIEFING SET APRIL 21


     NASA will hold a press conference at 12:30 p.m., Friday,
April 21, to discuss the experiment results from the March 29
commercial sounding rocket launch at White Sands Missile Range
and plans for NASA support of additional commercially-provided
flights.

     The Consort 1 mission, developed and managed by a NASA
Center for the Commercial Development of Space located at the
University of Alabama-Huntsville, was launched on a privately
furnished rocket in the first federally-licensed commercial
launch by a U.S. firm.

     Participants will include James T. Rose, NASA assistant
administrator for commercial programs; Dr. Francis Wessling,
associate director, consortium for materials development in space
at the University of Alabama-Huntsville; and Donald K. "Deke"
Slayton, Space Services Inc., Houston.

     The press conference will be conducted in the 6th floor
auditorium, NASA Headquarters, 400 Maryland Ave., S.W.,
Washington, D.C.

     The briefing will be carried live by NASA Select television
on Satcom F2R, Transponder 13, at 72 degrees west longitude, with
interactive question-and-answer capability.

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

Date: 17 April 1989 17:29:10 CDT
From: "Tom Kirke 996-4961" <[e-mail]>
To: <[e-mail]>
Subject: RE: Astrology

pitt!cisunx![e-mail]  (James C. Benz) writes:

>Not to lend any support to pseudo-science, but an interesting thing to look
>at in this respect is the police blotter of any large urban area on the
>night of a full moon.  I have heard the same story from several police
>officers here in Pittsburgh - craaazy things happen when there's a full
>moon, not just your run-of-the-mill stabbings and domestic violence, but
>the truly bizzarre.  Of course, this is probably purely subjective - people
>see a full moon and all their inhibitions go out the window, but an
>interesting phenomenon nonetheless.


The (R)eader, a free weekly newspaper here in Chicago, ran an article on this
about 2 years ago.  Despite the anecdotal evidence of Police, cabbies, etc
there is no evidence to back this claim.  Hospital admisssions, arrests,
and violent deaths are NOT correlated to the lunar phase.

To quote Sherlock Holmes, "There is nothing so tragic as a beautiful theory
destroyed by an ugly fact."

Tom Kirke

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

Date: Mon, 17 Apr 89 10:47:00 PDT
From: Peter Scott <[e-mail]>
Subject: Re: Rail-Guns and Asteroids

 [e-mail] writes:

>   Would it be reasonable to use Rail-Guns in mining an asteroid.
>   I am thinking that a large pellet of metal could be fired from an
>   asteroid based mining unit back to earth or the moon.  The pellet
>   could either be tracked and caught when it gets near the earth,
>   or it could be fired so it hits the moon, and then retrieved from
>   the (new) lunar crater.  The shape and composition of a pellet would
>   not be important.  Presumably, it should be small enough so that
>   it could not survive reentry on earth.  (Decreases liability
>   insurance.)  The rail gun could be operated with fusion or solar
>  generated electricity.

Hopefully the asteroid you're mining is still sufficiently massive by the time
you're finished that you don't alter its orbit too much with all this momentum
you're transferring... :-)

I would think it would be very expensive to recover metals from a high-
velocity impact crater on the Moon, when you could simply build another
mass driver in lunar orbit to receive the incoming load, at the same time
generating a fair amount of electrical power.  Of course, you'd have to have
either *very* good aim or a very wide mouth on your driver.

Peter Scott ([e-mail])

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

Date: 17 Apr 89 16:47:46 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Unmanned shuttle advantages (was: Re: alien contact)

In article <[e-mail]> [e-mail] (Matthew Francey) writes:
>  1) the 3g acceleration limit for a shuttle is a structural limitation, not a
>     human one.  At least, this is the impression I get from my readings.

There are tradeoffs here.  Higher acceleration is generally more efficient,
as you spend less time fighting gravity.  On the other hand, it needs more
powerful engines and heavier structure, and it's harder on the payloads.
The shuttle was specifically intended to be gentle with payloads (including
passengers), and I think this was the biggest consideration in picking the
peak acceleration.  Undoubtedly the current shuttle hardware is no heavier
than it has to be for that acceleration, meaning that you couldn't fly it
much harder.

3G is the usual rule of thumb for acceleration acceptable to a healthy
adult without prior preparation or selection.  Carefully selected and
trained astronauts can take rather more; the Saturn V accelerations were
considerably higher near upper-stage burnout.

(P.S. The hopes that the shuttle would be particularly gentle with payloads
have not panned out too well -- the engines are close to the payloads and
the vibration level is high.  There were also some other problems that
interfered with the original hope that shuttle payloads could be more
lightly built than those for expendables.  In particular, NASA paranoia
got in the way.  Shuttle payloads have to be able to take a 9G crash
load -- at right angles to the thrust axis! -- without breaking, even
though such a crash has a pretty good chance of breaking the shuttle
around them.)
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Reply-To: mordor!rutgers!pnet01.cts.com![e-mail]
Date: Mon, 17 Apr 89 09:04:29 PDT
From: mordor!rutgers!pnet01.cts.com![e-mail] (Jim Bowery)
To: hplabs!hpcea!hp-sdd!crash![e-mail]
Subject: Re: Rail-guns and Asteroids

In biar![e-mail]  (Robert J Woodhead) writes:

> In article <[e-mail]> [e-mail] writes:
> >    Would it be reasonable to use Rail-Guns in mining an asteroid.
>
> Given that for each reaction there is an equal and opposite reaction, it
> would make more sense to use the Railgun as a thruster; by ejecting a few
> percent of the mass of the asteroid at high velocity, one could move the
> asteroid to the vicinity of earth, where it would be convenient to mine.

The problem with moving asteroids around rather than returning mass to
Earth via rail-gun pellets is that the amount of time it takes to
move an asteroid makes it much less economic given interest costs
of capital equipment.  This is a factor which none of the asteroid
advocates have taken into account in their comparisons with lunar
resources.

Even though delta-v to many asteroids may be lower than access to
lunar material, round-trip time for the equipment ends up dominating
the cost optimization.

Therefore, using a rail-gun, mass-driver or any other high-speed
delivery mechanism for asteroidal material IS the best use of
those technologies rather than moving the asteroids to Earth.

In any case, if someone decided to begin moving an asteroid toward
Earth so they could mine it, I think I would take it upon myself
to preemptively assasinate them.
---------------------------------------------------------------------------
Jim Bowery    Phone: [phone]
PO Box 1981                  Join the Mark Hopkins Society!
La Jolla, CA 92038   (A member of the Mark Hopkins family of organizations.)

UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim
ARPA: crash!pnet01![e-mail]
INET: [e-mail]

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

Date: 17 Apr 89 16:37:44 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: U.S. vs Soviets (was Re: Alien contact)

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>> (yes, last I heard Freedom's internal volume will be less than that of
>> Skylab)...
>... the latest design for the station: two 40-foot
>U.S. modules (1 hab, 1 lab), 1 40-foot ESA module (lab), and 1 20-foot
>Japanese module (lab)...
> This seems to be a bit more voluminous than a gutted Saturn V third
>stage...

Look at the numbers, not at the appearance.  Even the third stage of a
Saturn V was *big*.

I admit that I haven't checked the numbers myself lately, mind you.

>... Incidentally, you avoided my question: you were going on about
>the probable superiority of Novy Mir...again, what greater capabilities will
>it have?

The fast answer is:  probably, more of everything.  It is also likely to
have some practical advantages, like using proven hardware, as opposed to
(for example) Freedom's insane 20kHz power system that nobody knows how
to build yet.

>> What does the US have in the pipeline in this class?  Mars Observer is
>> deliberately a rather unambitious mission.  Cassini and friends can't
>> really be said to be in the pipeline yet -- they've been trying to get
>> in for years.
>
>I wouldn't call Mars Ovserver unambitious.  From the looks of it, it is a
>fairly sophisticated mission...

It has grown some in the building, but it started out to be one of the
SSEC's "Observer class" missions, deliberately kept modest in hopes of
keeping costs low and permitting stable funding for an ongoing series.
(See below.)

>... We're beyond the days of the numerous, cheap probes whose sole
>mission was to survive long enough to snap pictures...

There are still a lot of places in the solar system that would benefit from
those numerous, cheap probes with cameras.  The real problem is that NASA
has forgotten how to build them.

>.... now
>the mission is a lot more complex, and you can't have five or ten of them
>in the planning stage; it's just too expensive...

The Observer class was specifically supposed to get us away from the one-
shot funding problem, by being cheap enough that a continuous pipeline
could be maintained on a constant yearly budget.  There is precedent for
this:  the Explorer series of near-Earth science missions has worked very
well on that basis.  The Observers don't seem to have managed it, alas.

>Last I heard, Cassini was entering the pipeline...

No, it's still banging on the door trying to get in.  What you read about
in AW&ST was NASA *proposing* it and CRAF, in a package deal, as the FY90
new-project start.  It remains to be seen whether Congress will buy it;
the package-deal business, in particular, is new and may not get a very
warm reception.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Date: 17 Apr 89 22:19:02 GMT
From: tektronix!tekig5![e-mail]  (Robin Adams)
Subject: Re: Assaying likely asteroids from afar

In article <[e-mail]>, [e-mail] (Mark Gellis) writes:
> Plus, if we simply fired this thing at the asteroid and got our information,
> and no one was hurt because it had, in fact, been used as a scientific
> instrument and not a weapon (that is, we present the Soviets with a fait
> accompli) what are they going to do about it?  Complain to the UN?  They'll
> look stupid and they know it.  Fire their own lasers at other asteroids
> to prevent an "asteroid gap"?  Good!  More data will come in and we will
> all know more about the asteroids.  Use it as an excuse to build their
> own nuke weapons in space?  Possibly, but then WE would have a legitimate
> right to complain to the UN and, besides, for the time being, the Soviets
> want to build their economy, not new weapons, so as long as we did not
> present a threat (which might be achieved by immediately sharing all
> data we get about the asteroids with them, or something like that), we
> could probably get away it.
>
> Any thoughts on this?


I'm not at all sure how this line of thinking help's the spirit of detente,
but anyway.....

If your not in Earth orbit, I would think that the U.S. (or whoever, for
that matter) would be outside the bounds of the treaty. So that could be Sun
orbit or half a dozen other types of orbit, some of which might take you
conveniently close to the asteroid objective(s). I'm assuming that the analysis
would be done in space and the data transmitted to earth.

Of course, one would need a little time on their hands....

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

Date: 18 Apr 89 06:35:22 GMT
From: unmvax!polyslo![e-mail]  (John McKernan)
Subject: Re: failures and engineering

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
> [Long history of Western space failures here.  I would assume that Soviet
>   craft never fail, from this list.  Removed for brevity's sake.]

>I see.  So, according to your hypothesis, the Soviets you so dearly love

>Voyager is out there laying the groudwork for the future exploration
>of the solar system, and you're sitting here on Earth complaining about the
>lube job.  I feel sure that if it had been a Soviet probe, you'd be singing
>it's praises almost daily.

WELL, I'm certainly glad to see we got a REAL AMERICAN here! Courageously
attacking the heathens who dare to criticize the US and say anything good
about the Soviets. I hereby nominate Matthew for the sci.space Joe McCarthy
award [insert overly loud canned applause here].

John L. McKernan.                    Student, Computer Science, Cal Poly S.L.O.
-------------------------------------------------------------------------------

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

Date: 17 Apr 89 03:50:17 GMT
From: tektronix!percival!bucket!loop![e-mail]  (Keith Lofstrom)
Subject: Neville Shute's "Slide Rule"

Suggested reading:  "Slide Rule" by Neville Shute, 1954.

This partial autobiography deals with Shute's years as an aviation designer
in Britain and later as the head of Airspeed Ltd.  The first half describes
the development of the Vickers R100 airship, in competition with the Labour
government's ill-fated R101 airship, and makes some points about government
versus private design efforts.  Some of the R101 screwups resemble those made
on the Space Shuttle 50 years later - like launching in bad weather.

The rest of the book follows Airspeed Ltd. from a fledgling ( :-) ) company
to a staff of 1000, in the midst of the Depression.  Interesting to folks
considering high-tech startups, less so to back-room types.

The writing is not as good as Shute's fiction, and I disagree with some of
what he says.   However, many of his observations are applicable today, to
space development or technology in general.  I read it after a good review by
Phil Salin, one of the principle investors in American Rocket Company, so you
guys are stuck with the book report, instead of rec.zeppelins.

--
Keith Lofstrom    keithl@loop    tektronix!tessi!qiclab!loop!keithl
Launch Loop, P.O. Box 1538, Portland, Oregon 97207   (503)-628-3645

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End of SPACE Digest V9 #381
*******************