Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO306.TXT

Internet Message Format | 1993-07-13 | 33KB

Date: Sat, 13 Mar 93 05:00:09
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #306
To: Space Digest Readers
Precedence: bulk


Space Digest                Sat, 13 Mar 93       Volume 16 : Issue 306

Today's Topics:
                           Building WF/PC-2
                           Bullets in Space
                           Charon (2 msgs)
                              Clementine
              DC-X; SSRT; Reply from Aspin's SDIO staff
                     Lunar Ice Transport (3 msgs)
Threat of mass cancellings was Re: Anonymity is NOT the issue (3 msgs)
                      Winding trails from rocket

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

Date: 12 Mar 1993 16:12 UT
From: Ron Baalke <[e-mail]>
Subject: Building WF/PC-2
Newsgroups: sci.space,sci.astro

From the "JPL Universe"
March 12, 1993

Bold measures result in quick turnaround for design,
building of WF/PC-2's mirrors.

By Diane Ainsworth

     When push came to shove in December 1991, and JPL's Dr.
James Fanson was asked to investigate the feasibility of building
three moveable fold mirrors for the new Wide Field/Planetary
Camera, he decided to go for broke.
     "There was no tried-and-true way to solve the problem we had
discovered with the Hubble Telescope's primary mirror," he said.
"We discovered that correcting the imaging performance of the
Hubble would require 10 times more precise optical alignment than
it did for the WF/PC-1 camera. So we set out to build a set of
articulating fold mirrors inside the camera that we could adjust
from the ground to realign images.
     "We were up against the tightest deadline we've ever had,"
Fanson said. "We needed to design and build the articulating
mirrors in less than 10 months, and we had to build the control
electronics in less time than it normally takes just to procure
the parts!
     "But JPL took some bold measures to ensure that our work was
high priority, and every procedure was completed as quickly as
possible," he said. "If ever there were a case-in-point of JPL's
ability to build something faster, better and cheaper, this was
it."
     Fanson assembled a team of the best talent at JPL, and they
hit the ground running.
     "We quickly realized that to meet the performance
requirements for these new mirrors, we needed to use new
technology ceramic actuators, which were developed by Litton/Itek
Optical Systems for the Department of Defense," he said. "The JPL
procurement people got Itek on contract with us in less than four
weeks."
     Fanson and his team next identified the solution that would
correct and bring images into focus from the Hubble Telescope's
8-foot-diameter (2.4-meter) primary mirror.
     "Basically what's going on inside the camera is that we're
canceling the error in the Hubble primary mirror with a matching
error intentionally polished onto a mirror in WF/PC-2," he said.
"This cancellation is straightforward in theory, but is made
difficult in practice because of the large magnitude of the
error. It's like trying to subtract a large number from another
large number and coming up with zero.  This only works if the
Hubble is exactly aligned with WF/PC-2, and that's the job of the
new articulating fold mirrors."
     Light entering the camera is split into four quadrants by
the pyramid mirror before reaching the relay secondary mirror.
The newly shaped secondary mirror, which is the size of a dime,
is where the cancellation of the Hubble error actually occurs.
Light then continues on to the camera's charge-coupled devices
(CCDs), where the image is formed.
     Fanson, along with Bob Bamford and Paul MacNeal of the
Applied Technologies Section 354, decided that they would have to
replace the "fixed" -- unmoveable -- fold mirrors in the camera
with articulated, adjustable mirrors that could be tipped and
tilted to make sure the light beam fell precisely in the middle
of the secondary relay mirrors. Not only would that alignment
capability be necessary after the vibrations and jitters of
launch and installation, Fanson said, but it would be a means of
guaranteeing on-orbit alignment in later months.
     "The trick was to come up with a design that would fit in a
very tiny space, less than nine-tenths of an inch thick and 1.6
inches in diameter," he said.  "The parts are so small that they
were assembled under a microscope." Designing the assembly
tooling and procedures was the responsibility of Al Delgadillo of
the Mechanical Systems Development Section 352.
     Changes in mirror position are accomplished by each mirror's
tilt mechanism, which is like a three-legged stool, Fanson
explained. The legs are composed of tiny ceramic actuators that
lengthen when a voltage is applied to them.
     "By controlling the lengths of the three legs, we can
control the tip and tilt of the mirror," Fanson said. "We are
talking about very small motions -- the total stroke of the
actuators is equal to the length your hair grows in 15 minutes."
     The amount of voltage applied to the actuators is programmed
by computers at the ground operations facility at Goddard Space
Flight Center in Greenbelt, Md.
     After assembly at JPL and Itek, the mirrors went through
environmental testing. When specifications were met, they were
delivered to the WF/PC-2 integration and test team in early July
-- with two days to spare in the schedule. Meanwhile, Tom Radey
of the Imaging Systems Section 381 was busy building an extremely
stable set of control electronics to command the 18 actuators in
the three articulating mirrors.
     "We made it in the nick of time, but we made it," said
Fanson, who was awarded a 1992 Lew Allen Award for the
articulating fold mirror effort. "We came in under budget and on
time."
     Launch of the Hubble Space Telescope servicing mission,
STS-61, is tentatively scheduled for Dec. 2, 1993, aboard the
space shuttle Endeavour. Installation of the new Wide
Field/Planetary Camera will occur on the second day of astronaut
extra-vehicular activities (EVA), said Michael Devirian, WF/PC-2
deputy program manager and head of servicing and operations.
     Adjustments to the camera and other instruments will take
about a month, Devirian said. Ground-controllers will have to
wait three weeks before they can turn on the coolers to bring the
camera sensors down to about minus 80 degrees Celsius (about
minus 112 degrees Fahrenheit). Then they will begin taking
photographs, analyzing the images and fine-tuning the new
articulating fold mirrors.
                          ###
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | It's kind of fun to do
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | the impossible.
|_____|/  |_|/       |_____|/                     | Walt Disney

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

Date: Fri, 12 Mar 1993 14:46:04 GMT
From: "Matthew R. Feulner" <[e-mail]>
Subject: Bullets in Space
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Tom A Baker) writes:
|> In article <[e-mail]> Leigh Palmer <[e-mail]> writes:
|> >In article <[e-mail]> Brandon France,
|> >[e-mail] writes:
|> >
|> >>What would happen if an astronaut was in a geostationary orbit and fired
|> >>a rifle directly toward the earth?  What path would the bullet take?
|> >
|> >The bullet would follow an elliptical path for any muzzle velocity less
|> >than the orbital velocity (~3 km/s), and a hyperbolic path for any
|> >velocity greater than this (Kepler, Newton).
|> [deletion]
|> >If the bullet is retained in an elliptical orbit then the period of the
|> >orbit will be greater than one day, since the energy per unit mass is
|> >larger for the bullet (that is, it is less negative) after it has been
|> >fired than before.
|>
|> Waitaminit.  I was taught that, if the delta vee was directly through the
|> center of the earth, then, elliptical orbit or not, the >impulse< would
|> not change the period of the orbit.  (Ignoring things like atmospheric
|> drag, etc.)  The bullet would still be geosynchronous.
|>
|> tombaker

Nope, if the delta-V increases the magnitude of its velocity at a particular
radius, there will be a net increase in orbital energy, and therefore, an
increase in orbital period.  A delta-V directed towards the earth, but
slightly "behind" it (as in slightly in the direction opposite to your velocity),
would keep the same velocity magnitude (just changing direction), and
therefore the same period.

Matt

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

Date: Fri, 12 Mar 1993 08:43:26 GMT
From: Dave Michelson <[e-mail]>
Subject: Charon
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Mike Van Pelt) writes:
>
>Speaking of Pluto imaging, a couple of years ago someone was supposedly
>recording the brightness fluctuations of the Pluto-Charon system while
>Charon and Pluto were occulting each other, and they were going to
>analyze the data in order to produce an image.
>
>Am I misremembering?  Did anyone do this?

The short answer is yes.

In 1984, Marc Buie and Robert Marcialis, working independently, developed
computer models of surface features on Pluto that could closely approximate
the fluctuations in the planet's 6.39-day light period.  The models that
they produced were similar but not identical.  The eclipse season of which
you speak began in 1985 and ended in 1990.  As of 1990, the results suggested
that Buie's model is closer to the truth although other interpretations have
been suggested.

For more information, check out:

R.P. Binzel, "Pluto," Scientific American, June 1990, pp. 50--58.

M. Littman, "Planets Beyond: Discovering the Outer Solar System." 2nd ed.
New York: Wiley, 1990, pp. 170--194.

J.K. Beatty and A. Chaikin, Eds. "The New Solar System." 3d ed. Cambridge:
Cambridge Univ. Press, 1990, pp. 202--206.

Now that we've got the preliminaries out of the way, maybe Dave Tholen
or someone else who is active in the field can bring us up to date on what
has happened since 1990...

---
Dave Michelson                             University of British Columbia
[e-mail]                                  Antenna Laboratory

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

Date: Fri, 12 Mar 1993 10:07:24 GMT
From: Dave Tholen <[e-mail]>
Subject: Charon
Newsgroups: sci.space

Dave Michelson writes:

> Now that we've got the preliminaries out of the way, maybe Dave Tholen
> or someone else who is active in the field can bring us up to date on what
> has happened since 1990...

Gladly.  The earlier models computed by Marcialis and Buie utilized circular
spots to approximate the surface albedo distribution.  Buie and I, working
with Keith Horne, have since based a newer model on the maximum entropy
technique.  Basically, the technique finds the smoothest possible albedo
distribution consistent with the data.  It avoids the discontinuites in the
albedo distribution that the circular spot model has, though anyone who has
looked at Mars knows that the change in albedo at the edge of the polar caps
can indeed be rather abrupt.  This maximum entropy model is the first to
incorporate all the wonderful mutual event data that I worked so hard to
acquire for six years.  The albedo model does assume the orbital parameters
and sizes that I derived from the mutual event data.  Those model parameters
can now be tweaked, thanks to an improved orbital radius from Space Telescope,
though I'm waiting for the results of some ground-based imaging we did last
year before adopting the HST result as definitive.  The extensive set of
mutual event data that Rick Binzel obtained at McDonald observatory has been
used by him and Eliot Young to produce another albedo model, though for only
the facing hemispheres of Pluto and Charon.  To first order, the model results
agree rather nicely.  They haven't attempted to do a global solution the way
Buie did.

The next improvement is likely to come after the rotational lightcurves of
Pluto and Charon are separated, which Buie and I are currently working on
using HST data.  The global solution for the anti-facing hemispheres is
pretty poorly constrained right now because the only data we have to go on
is lightcurve photometry of the system as a whole.  Individual lightcurves
will help immensely.

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

Date: Fri, 12 Mar 93 15:05:54 EET
From: [e-mail] (F.Baube x554)
Subject: Clementine

Bill Higgins-- Beam Jockey <[e-mail]>
> The major purpose of Clementine is to test SDI sensors in space.
> As long as they need to fly a couple of UV-visible and IR cameras,
> and a laser altimeter/LIDAR, they decided to do some lunar and
> asteroid science with them.

It's good to know that arrangements like this are possible,
even if it sounds like the priorities are bass-ackwards.

Are there any other such arrangements proposed, to use an
SDI testbed and SDI money to do some planetary science ?
Or does this look to be a one-off ?

--
* Fred Baube GU/MSFS      * We live in only one small room of the
* Optiplan O.Y.           * enormous house of our consciousness
* [e-mail]       *       -- William James
* It's lo-og, it's lo-og, it's big, it's heavy, it's wood !
* It's lo-og, it's lo-og, it's better than bad, it's good !
* #include <disclaimer.h>

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

Date: Fri, 12 Mar 1993 16:30:47 GMT
From: Nick Haines <[e-mail]>
Subject: DC-X; SSRT; Reply from Aspin's SDIO staff
Newsgroups: sci.space

Earlier in the year I wrote letters to various people in Washington,
asking for continuing support for SSRT (i.e. DC-X). This morning I
received a reply, which I reproduce (without permission) below. My
comments:

(0) My letter got some attention. I read that as a good sign. Anyone
    who supports DC-Y and hasn't done anything about it yet should
    write to Clinton, Gore, and Aspin right now. Including addressing
    the envelopes it took me about 30 minutes. Allen will give you the
    addresses.
(1) SDIO have PR staff who are smart, know what they're talking about
    (I didn't mention SSTO in my letter), and see the wisdom of SSTO.
(2) DC-Y is uncertain and (IMO) unlikely to receive SDIO money in the
    current climate.
(3) Delta Clipper will not receive SDIO money, but might get some
    money from somewhere. Whether `another agency' means `another
    government agency' is unclear.

Nick Haines [e-mail]
---------------------------clip here----------------------------------

               Department of Defense
        Strategic Defense Initiative Organization
            Washington, DC 2030-7100

                            March 4, 1993

Dear Mr. Haines:

Thank you for your letter to Secretary of Defense Aspin expressing
your, and asking for his, support of the Strategic Defense Initiative
(SDIO) Single Stage Rocket Technology (SSRT) Program. The SSRT program
is completing construction of the McDonnell Douglas DC-X technology
demonstrator and will begin extensive static and flight testing this
spring. Following completion of this series of tests, SDIO will then
decide whether to proceed with the development and launch of a fully
reusable, suborbital launch vehicle to support our technology
development needs.

SDIO will not develop an orbital derivative. However it is posible
that our efforts with the DC-X technology demonstrator will pave the
way for another agency to continue the development of the SSTO
concept. This could provide the nation with a significantly lower
cost launch system, placing the United States into a preeminent
position in the world space arena.

I appreciate your interest in the future of the United States space
program, and more particularly, your support for the SSRT program.

                    Sincerely,


                    RICHARD McCORMACK
                    Chief, Community Relations

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

Date: Fri, 12 Mar 1993 07:43:37 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Lunar Ice Transport
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Papp) writes:
>In article <[e-mail]> [e-mail] writes:
>>Ross  Borden ([e-mail]) wrote:
>>:     In all the Lunar ice transportation proposals that I've seen,
>>: nobody has mentioned what would be, on Earth, the most obvious: overland
>>: hauling.
>>:     To maintain high through-put, a continuous stream of vehicles
>>: would haul ice from the polar ice mines to the equatorial processing
>>: plants, and then dead-head back (unless there was some return cargo.)
>>
>>The extremely tenuous Lunar atmosphere offers another "overland hauling"
>>possibility: ballistic delivery.  Put a fast conveyor belt at one end,
>>and a large bucket at the other:
>>
>>
>From a student who is doing this next to impossible project, we are
>currently designing a rail gun to deliver the ice with a hopper at
>the end to catch it for much the same reasons you gave.  Unfortunately,
>there are other considerations.  What happens to the ice when it
>accelerates.  Does it melt, stay solid, explode?  For now, I'm assuming
>it stays solid.  Controlability could also be a problem.

Seems to me you guys are overlooking the obvious, a pipeline. During
the lunar daytime, surface temperatures are high enough to boil water.
So you have a wet steam line producing it's own pumping pressure. It
would only work 2 weeks a month, but pipelines are the most efficient
way to move material on Earth. I would suggest that they would also
be the most effective way to move large amounts of material point
to point on the lunar surface.

Gary

--
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244     |                     |

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

Date: Fri, 12 Mar 1993 14:08:30 GMT
From: Dave Stephenson <[e-mail]>
Subject: Lunar Ice Transport
Newsgroups: sci.space

[e-mail] (John Papp) writes:

>In article <[e-mail]> [e-mail] writes:
>>Ross  Borden ([e-mail]) wrote:
>>:     In all the Lunar ice transportation proposals that I've seen,
>>: nobody has mentioned what would be, on Earth, the most obvious: overland
>>: hauling.
>>:     To maintain high through-put, a continuous stream of vehicles
>>: would haul ice from the polar ice mines to the equatorial processing
>>: plants, and then dead-head back (unless there was some return cargo.)
>>
>>The extremely tenuous Lunar atmosphere offers another "overland hauling"
>>possibility: ballistic delivery.  Put a fast conveyor belt at one end,
>>and a large bucket at the other:
>>
>>
>From a student who is doing this next to impossible project, we are
>currently designing a rail gun to deliver the ice with a hopper at
>the end to catch it for much the same reasons you gave.  Unfortunately,
>there are other considerations.  What happens to the ice when it
>accelerates.  Does it melt, stay solid, explode?  For now, I'm assuming
>it stays solid.  Controlability could also be a problem.
>--
>-------------------------------------------------------------
>|                  |                            |
>| John L. Papp        | "You sound like a manure salesman   |
>| [e-mail]  |  with a mouth full of samples."     |

Ok serious for a moment. The idea of the mass flinger has been around
for at least a decade. The Technical University of Berlin produced some
very interesting studies on Lunar transport int he 1980's, if you can
read technical German. Prof. Kolle is the charman of the International
Astronautics Accademy sub comittee on Lunar Base Construction.

Don't try the rail gun. This is a contact device and the projective
will get HOT, by the time it leaves the barrel it will be plasma!
The coil gun on the other hand should be alright. You only need to
accelerate at a few hundred G's and there is no contact in the barrel.
Zubrin had an even more crude system, the lunar sling. Tie your ice
to a long Kevlar rope. Start rotating it around the thrower and pay out.
When the rope is long enough and the direction of flight is in the right
direction, let go!. I will not go into the details of balencing the momentum
at the moment of let go. Directional control should be handlable. Use a laser
beam rider using 'brilliant pebbles technology' to guide the payload into
the catcher. Incidently if the launcher is electromagnetic, leave the
bucket on the payload of ice (which should be reinforced with rock wool BTW)
and rotate in space to enter the catcher bucket first. The catcher could
now be a similar electromagntic launcher in reverse acting as an eddy current
brake. And so in one sudden bolt you get the launch energy back. Neat way
of shipping energy from poles, where sunlight is permanent to lunar equator
during the night!

Hope ideas useful.

--
Dave Stephenson
Geodetic Survey of Canada
Ottawa, Ontario, Canada
Internet: [e-mail]

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

Date: Fri, 12 Mar 1993 14:57:51 GMT
From: "Matthew R. Feulner" <[e-mail]>
Subject: Lunar Ice Transport
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Philip Young) writes:
|> In article <[e-mail]>, [e-mail] (Ross  Borden) writes:
|> |>
|> |>     In all the Lunar ice transportation proposals that I've seen,
|> |> nobody has mentioned what would be, on Earth, the most obvious: overland
|> |> hauling.
|>
|> The proposed lunar tractor/trailer, plus road engineering, would be
|> incredibly expensive.  A polar rail gun avoids all the problems with
|> surface transportation.  Accuracy would be great in vacuo, and you can
|> charge up the capacitors with plentiful, cheap, solar power.  Even
|> during lunar winter, you could beam power from a satellite, or operate
|> the other pole.
|>
|> Designing an equitorial catcher's mitt could be a challenge, though.
|>
|> --
|> Philip R. Young
|> Data General Australia Pty. Ltd.


The rail gun idea has the advantage that you only have to deal with
reliability at two points - not a continuum between the beginning and
end like a pipeline or railroad.

The catchers mitt would only be a problem in deciding with what to catch the
ice.  The launcher could relay the data of the trajectory and have the mitt
adjust position accordingly.  So, the mitt could have a limited area to move,
and the launcher wouldn't have to have extreme precision (down to a couple of
feet miss at the target).  The flight would probably (off the top of my head)
take a few minutes, so the catcher could be moved manually, or at least without
computer control.

Matt

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

Date: 12 Mar 1993 12:59:14 GMT
From: David Clunie <[e-mail]>
Subject: Threat of mass cancellings was Re: Anonymity is NOT the issue
Newsgroups: news.admin.policy,news.admin,comp.org.eff.talk,sci.space,alt.privacy

In article [e-mail], [e-mail] (Richard E. Depew) writes:

>     I am testing a shell script to carry out "Automated Retroactive
>Minimal Moderation" in response to Julf's (and your) suggestion that
>the only way to control anonymous posting to groups that don't want it
>is through moderation.  It cancels articles posted from anon.penet.fi.
>I've tested it on recycled postings with a "local" distribution and
>it works nicely.  I propose to arm "ARMM" with an unrestricted
>distribution for the "sci" hierarchy this weekend if Julf doesn't
>accept the proposed compromise or a reasonable alternative by then.

In article [e-mail], [e-mail] (Afzal Ballim) writes:

>Get ready for a "cancelling" war. Heh, this may be
>a good thing. Think of how much less news we'll all have to read each day :-).
>I suggest you think through your idea before implementing it.

I think Richard that perhaps you should heed Afzal's warning ... cancelling
articles has traditionally been something that people are very sensitive
about, much more so than dealing with the odd abusive anonymously posted
message.

I presume that cancel messages can be cancelled ... though I haven't
experimented with this yet, but it looks like I might have to. In fact I
think I will probably just turn off response to cancel messages totally if
you go ahead with this scheme, and I encourage other news administrators
to do the same ... they were a bad kludge in the first place and still are.
It seems to me they are rarely used for other than controversial purposes
like you are proposing (I don't like other people's postings so I won't let
anyone else read them).

I really think you are getting carried away with a non-issue here, and
inflamming the situation is going to make you extremely unpopular, and
undoubtedly start a "cancelling war" at the very least.

No-one has appointed you as the moderator of all the non-alt groups
retrospectively or otherwise, and no-one is likely to appoint anyone else
in such a position either.

If you are so mad keen on democracy why don't you put it to a vote in
each of the proposed groups ... let's see we could have a sci.space.moderated,
and sci.space.unmoderated and a sci.space.richard.depews.selection.

> Or could it be that you think it couldn't be fair if
> the majority disagees with you?  :-)

I think that perhaps this is a case of the pot calling the kettle black - I
have not seen a majority in this group come out in favour of your proposals,
in fact there has been a distinct silence on both sides of late, reviewing
what is left in my spool area.  I don't think that you have a mandate to
take this unilateral action, certainly not on the basis of the few vocal
but regular contributors to this thread.

> There shouldn't be much controversy over this, but there will be
> anyhow.  :-)

There should be and there will be ... you are way out of line here Richard,
regardless of how many smileys you tack on the end of your message.

I hope you are prepared to take responsibility for what is going to happen
to your institution's news and mail servers if you go ahead with this plan.

I would also be interested to hear a legal opinion on this matter. Cancelling
someone else's posts may well be infringing on their First Ammendment rights,
not to mention a potential breach of that Electronic Privacy Act or whatever
it is called. I am sure your institutions lawyers will be real impressed when
the ACLU and the EFF come knocking on their doors on behave of some angry
plaintiff.

You frequently extoll the virtues of being reasonable. I suggest you take
your own advice and drop this one-man crusade to cleanse Usenet of the
virulent anonymous strain. It is only going to bring you grief in the end
and waste more peoples' time than has already been wasted deailing with this
issue.

I am sure you don't want to become Usenet's next "J Palmer" in terms of
reputation. (This is reference is becoming a bit like the "who is John Galt ?").

---
David A. Clunie ([e-mail])

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

Date: Fri, 12 Mar 1993 14:35:49 GMT
From: Afzal Ballim <[e-mail]>
Subject: Threat of mass cancellings was Re: Anonymity is NOT the issue
Newsgroups: news.admin.policy,news.admin,comp.org.eff.talk,sci.space,alt.privacy

In article <[e-mail]>, [e-mail] (David Clunie) writes:
|> In article [e-mail], [e-mail] (Richard E. Depew) writes:
|>
|> >     I am testing a shell script to carry out "Automated Retroactive
|> >Minimal Moderation" in response to Julf's (and your) suggestion that
|> >the only way to control anonymous posting to groups that don't want it
|> >is through moderation.  It cancels articles posted from anon.penet.fi.
|>
|> If you are so mad keen on democracy why don't you put it to a vote in
|> each of the proposed groups ... let's see we could have
|> a sci.space.moderated,
|> and sci.space.unmoderated and a sci.space.richard.depews.selection.
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

No, no, that would be sci.space.anonymously-moderated

i.e., it's been moderated to remove anonymous postings, or it's
been moderated anonymously (people don't know it's been moderated).

We could then also have sci.space.richard-depews-moderate where anything
from Richard has been cancelled, sci.space.richard-depews&&anonymous-moderated
which has neither anonymous posts nor posts from Richard,
sci.space.com&&edu-moderated which contains no posts from people at .com or
.edu sites, etc., etc., etc. The only problem, of course, is that what is
being proposed is not the creation of such newsgroups, but rather that (for
example) sci.space becomes the intersection over all such groups.

--
Afzal Ballim             | Internet: [e-mail]
ISSCO, University of Geneva  | X400: S=afzal;OU=divsun;O=unige;
54 route des Acacias         |       PRMD=switch;ADMD=arcom;C=ch
CH-1227 GENEVA (Switzerland) | UUCP: mcvax!cui!divsun.unige.ch!afzal
Tel: [phone]        | FAX: [phone]

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

Date: 12 Mar 93 16:21:39 GMT
From: Dave Hayes <[e-mail]>
Subject: Threat of mass cancellings was Re: Anonymity is NOT the issue
Newsgroups: news.admin.policy,news.admin,comp.org.eff.talk,sci.space,alt.privacy

[e-mail] (David Clunie) writes:
>>     I am testing a shell script to carry out "Automated Retroactive
>>Minimal Moderation" in response to Julf's (and your) suggestion that
>>the only way to control anonymous posting to groups that don't want it
>>is through moderation.  It cancels articles posted from anon.penet.fi.
>>I've tested it on recycled postings with a "local" distribution and
>>it works nicely.  I propose to arm "ARMM" with an unrestricted
>>distribution for the "sci" hierarchy this weekend if Julf doesn't
>>accept the proposed compromise or a reasonable alternative by then.

How very nice of you.

Have you considered that your actions may cause many news admins to cancel
all control messages coming from your site?
------
Dave Hayes - Network & Communications Engineering - JPL / NASA - Pasadena CA
[e-mail]       [e-mail]         ...usc!elroy!dxh

   History is not usually what has happened.
            History is what some people have thought to be significant.

--
Dave Hayes - Network & Communications Engineering - JPL / NASA - Pasadena CA
[e-mail]       [e-mail]         ...usc!elroy!dxh

          To the ignorant, a pearl seems a mere stone.

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

Date: 12 Mar 1993 11:46:02 GMT
From: Carl J Lydick <[e-mail]>
Subject: Winding trails from rocket
Newsgroups: sci.astro,sci.space,sci.geo.meteorology

In article <[e-mail]>, [e-mail] (boyd johnson) writes:
>Is it the wind currents that twists the contrail or does the rocket
>follow a looping, circling route?

The contrail of a rocket that follows a "looping, circling route" is usually
marked by a large puff of debris at the end, when the range safety officer
triggers the rocket's auto-destruct mechanism.
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: [e-mail] | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.

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

End of Space Digest Volume 16 : Issue 306
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