Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v16_3/v16no324.txt

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Date: Wed, 17 Mar 93 05:13:32
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #324
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 17 Mar 93       Volume 16 : Issue 324

Today's Topics:
                             1-800-NASA?
                    20Khz Power supplies. (5 msgs)
   Actual 20kHz question! (was Re: 20Khz Power supplies.) (2 msgs)
                   Cosmonaut Georgi Grechko in USA
             Dennis and new tech (was Re: Without a Plan)
                         Galileo HGA (2 msgs)
               Just a little tap (was Re: Galileo HGA)
                         Lunar Ice Transport
                   Mars Observer Update - 03/16/93
                       NASA SELECT TV (2 msgs)
                  Response to various attacks on SSF
                            Without a Plan

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: Tue, 16 Mar 1993 18:50:31 GMT
From: Martin Connors <[e-mail]>
Subject: 1-800-NASA?
Newsgroups: sci.space

In article <[e-mail]> [e-mail]
(Al Globus) writes:
> The Clinton administration has a new program to find ways to improve
> the government.  Each part of the government has an 800 number to call
> to note problems and suggest solutions.  Gore is running this.
>
> Does anyone know the number for NASA?
>
> Thanx.

 Try calling 1-800-555-1212 which is 800# directory assistance. Please ask
them if the NASA number is toll-free from Canada too :)  !!

--
Martin Connors         |
Space Research         | [e-mail]  [phone]
University of Alberta  |

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

Date: 16 Mar 93 21:25:55 GMT
From: Thomas Clarke <[e-mail]>
Subject: 20Khz Power supplies.
Newsgroups: sci.space

In article <[e-mail]>
[e-mail] writes:
> The MCM 7805 series regulator
> that is used by the millions to regulate +5 VDC is actually a 40 Khz chopper
> regulator in architecture.  That is the DC voltage is converted to
> 40 Khz and then rectified to the new lower DC voltage.

Is this true? Most 7805s I've come across are linear.
--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: 16 Mar 93 21:39:19 GMT
From: Henry Spencer <[e-mail]>
Subject: 20Khz Power supplies.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>>... Name 3 projects that have used 20Khz  power.  name 3 companies
>>that produce 20Khz power components.
>
>How about Lambda, ACDC Electronics, IBM, Apple, and zillions of Tiawan
>clone makers. 20 kHz power is old hat. Likely the computer you are
>reading this on uses 20 kHz, or higher, frequencies in it's power
>systems...

*In* its power systems.  Not outside them.  Come now, Gary -- Pat wasn't
asking for people who make 20kHz transistors, he was asking for people
who make 20kHz lightbulbs or fans or breaker panels or radios.

And when it comes to actually distributing power to its internals, that
computer uses DC.  (It just might use 60Hz AC for its fans.)

Gary is also correct, in a way he didn't intend :-).  *Within* power
systems, 20kHz is old hat, i.e. obsolete.  Modern switching power supplies
are moving strongly towards much higher frequencies.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 16 Mar 1993 16:30 CST
From: [e-mail]
Subject: 20Khz Power supplies.
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Thomas Clarke) writes...
>In article <[e-mail]>
>[e-mail] writes:
>> The MCM 7805 series regulator
>> that is used by the millions to regulate +5 VDC is actually a 40 Khz chopper
>> regulator in architecture.  That is the DC voltage is converted to
>> 40 Khz and then rectified to the new lower DC voltage.
>
>Is this true? Most 7805s I've come across are linear.
>--

Tom take a look at the noise spectrum output of a 7805. You will see that
it is concentrated (fundamental frequency) at 40 Khz. Then go to a book
on the theory on the part. ( I think the original design is from TI) and
read about switching regulators. These are early generation parts and
are only about 50% efficient, although they can accept quite a range of
input voltage. (8.5-18 VDC for +5 VDC) I think the proper term is a
chopper regulator for these early generation devices.

I think what you are talking about is that they are listed in the linear
devices catalogs sometimes. TI has an exclusisve book for Regulators.

Dennis, University of Alabama in Huntsville

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

Date: Tue, 16 Mar 1993 21:18:38 GMT
From: Brad Whitehurst <[e-mail]>
Subject: 20Khz Power supplies.
Newsgroups: sci.space

[reams of Pat's schoolyard taunts deleted]
    Christ on a crutch!  My kill file for this group is telling me
that it's time to bug out!  It's bigger than the rest of my groups
combined!  I'll really miss the good stuff from people like Henry,
Dennis, Fred, Mary, Ron, and Allen, but I'm sick of the drivel.  I
hope Ron Baalke and anyone else who has good info, esp. on DC-X when
launch time nears, will post it to sci.space.news, 'cause I'm afraid
it'll be lost on the flaming assholes who are clogging up sci.space.

Ciao.
--

Brad Whitehurst    |   Aerospace Research Lab
[e-mail] |   We like it hot...and fast.

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

Date: Tue, 16 Mar 1993 22:07:15 GMT
From: Edmund Hack <arabia!hack>
Subject: 20Khz Power supplies.
Newsgroups: sci.space

In article <[e-mail]>
     [e-mail] writes:
>The problem with 20Khz per se is that some women would not be able to stand
>being around it, as a few women can hear frequencies that high. I kinda
>doubt this is a problem since many computer monitors also run in this frequenc
>domain.

Actually, a few men (myself included) can hear that high.  I can hear
ultrasonic intrusion sensors, some of which are quite loud.  (Ironic
note - I had to have a stereo store manager move a bunch of speakers to
another test room since the main test room was covered by an ultrasonic
sensor, which I could hear.)  I have had to change monitors a few time
when the internal transformer works loose and oscillates at 17 kHz
plus.  It is a very unpleasant sound.

I had a few contacts with Lewis while the 20kHz power testbed was being
set up and the advantages of efficiency and lighter weight you cited were
major considerations.  Losses in the power systems (esp. in the form of
heat in the modules) also causes the thermal system to be larger.  The
tradeoff between DC/60 Hz/400 Hz/20 kHz is a complicated one that is
multi-dimensional.

--
Edmund Hack - Lockheed Engineering & Sciences Co. - Houston, TX
[e-mail] - I speak only for myself, unless blah, blah..
"Everybody wants prosthetic foreheads on their real heads"
"I'm not an actor, but I play one on TV."

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

Date: 16 Mar 93 08:05:08 GMT
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Actual 20kHz question! (was Re: 20Khz Power supplies.)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes:

[Dennis commendably inserts a technical discussion, which Pat
originally asked for, into the middle of the interminable ranting
we've seen in this thread. I learned a number of interestin things
about power from his posting. Which causes me to ask a technical
question.]

> Problems with 20 Khz
>
> 1. IF cabin pressure is lost then the system can arc.
> 2. Non Standard
> 3. RFI/EMI (can be solved with filters however)
>
> Actually not bad except for #1. If cabin pressure is lost you have to
> shut down your power system. No good for system recovery. From what I
> remember that is the final reason that 20Khz died.

I don't understand this.  If the cabin pressure gets low (somewhere
between "crummy vacuum" and "very hard vacuum") it becomes easy to
ionize the air.  I know this depends on the voltage you're running.
But could you explain why the frequency is important?  (I infer that
it's worse at 20 kHz than at 400 Hz.)

> This new (or actually very old if you remember the S-100 computers) is that
> you no longer have a central power supply that provides all of the system
> voltages. You take a primary distribution voltage and then locally
> regulate to the voltage desired.

Careful, Dennis, your age is showing!

Reviewing *Time Trax*: "In this future  | Bill Higgins, Beam Jockey
police have gotten more technical,      | Fermilab
computers have gotten much smaller,     | Bitnet: [e-mail]
criminals have become much cleverer,    | Bitnet: [e-mail]
and matte painters                      | SPAN/Hepnet: 43011::HIGGINS
have lost the secrets of their ancestors." --Mark Leeper

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

Date: 16 Mar 1993 16:23 CST
From: [e-mail]
Subject: Actual 20kHz question! (was Re: 20Khz Power supplies.)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes...
>In article <[e-mail]>, [e-mail] writes:
>
>[Dennis commendably inserts a technical discussion, which Pat
>originally asked for, into the middle of the interminable ranting
>we've seen in this thread. I learned a number of interestin things
>about power from his posting. Which causes me to ask a technical
>question.]
>
>> Problems with 20 Khz
>>
>> 1. IF cabin pressure is lost then the system can arc.
>> 2. Non Standard
>> 3. RFI/EMI (can be solved with filters however)
>>
>> Actually not bad except for #1. If cabin pressure is lost you have to
>> shut down your power system. No good for system recovery. From what I
>> remember that is the final reason that 20Khz died.
>
>I don't understand this.  If the cabin pressure gets low (somewhere
>between "crummy vacuum" and "very hard vacuum") it becomes easy to
>ionize the air.  I know this depends on the voltage you're running.
>But could you explain why the frequency is important?  (I infer that
>it's worse at 20 kHz than at 400 Hz.)
>
>> This new (or actually very old if you remember the S-100 computers) is that
>> you no longer have a central power supply that provides all of the system
>> voltages. You take a primary distribution voltage and then locally
>> regulate to the voltage desired.
>

The problem is that with AC circuits, the higher the frequency of operation,
the closer to the surface of the conductor the current flows.  This is
called the "skin effect" and is as old as electronics.  It turns out that
the crossover point between primarily conducted energy and radiated
energy is somewhere around 20 Khz, depending on the type of conductor used.
At frequecnies significantly above audio frequencies, the majority of
electrical current is carried in the uppermost layers of the conductor and
almost none in the center of teh conductor. This is why no one builds
(or only the Navy) builds radios that operate at frequencies less than 20
khz.

DC systems have all of their current flowing in the interior of the circuit.
This is why you do not have EMI/RFI problems with DC power.  While the
DC-DC conversion technology is wonderful in its ability to make lighter
smaller supplies for secondary power they have horrendous problems with
EMI/RFI. Mys system that is flying on SpaceHab locked up the Mac so many times
that I had to completly redesign the filtering on the Mac as well as up front
in order for the system to work. Filter theory and EMI/RFI are black arts
and there is good cash, both in terrestrial as well as the space arena
for experts that KNOW what they are doing. I know a certain NASA lab that
has an open slot for a GS14 in this very area that they have not been
able to fill for years!

By the way, is there anyone out there who knows about power supply isolation
on spacecraft? We sure could use some INFORMED help in this matter. I am
debating different approaches right now on this subject.

So pat I snookered you on this one to prove the point that you don't
always know what you are talking about. :-)

Dennis, University of Alabama in Huntsville

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

Date: 16 Mar 93 21:06:39 GMT
From: Josh Hopkins <[e-mail]>
Subject: Cosmonaut Georgi Grechko in USA
Newsgroups: sci.space

[e-mail] (George Hastings) writes:

>Dr. Georgi Grechko, Cosmonaut
>Lecture Tour of the United States

>Champaign, IL                March 16
>Speak/ Radio-Theater in Champaign    March 17

I'm going to this tomorrow and I may try and post a summary if I'm not too
bogged down.  Grechko was on the Soviet Lunar landing team and visited three
Salyuts for a total of about 125 days in space so he should have some
interesting things to talk about.


--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de la realiser"
             -Jules Verne

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

Date: 16 Mar 93 18:09:15 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Dennis and new tech (was Re: Without a Plan)
Newsgroups: sci.space,talk.politics.space

In article <[e-mail]>, [e-mail] (Josh Hopkins) writes:
>>In <[e-mail]> [e-mail] (Nick Szabo) writes:
>>>Until we _lose_ the delusional, cultish cant of Wingo's, that our
>>>vision must be one (his) and must never change, regardless of
>>>changes in technology, politics, etc., NASA and space fans will
>>>continue beating our heads against a brick wall.
>
> Nick, Dennis was working on a tethered satellite system which, according to
> Space News, is scheduled to launch this week with a total project cost of
> $10 million to NASA.  It hardly seems effective to use him as the archetypal
> paperpushing luddite astronaut groupie.

Which, it is worth pointing out, is trying out risky new technologies
in its computer, solar cells, and imaging device.  This is something
that Nick, Henry, and many others advocate strongly.  If SEDSAT-1 is
successful, these gadgets will have a track record and people will be
willing to incorporate them into future satellites. (Though I think
Dennis's payload goes up on the *second* SEDS launch, not the current
one.)

"Do you know the asteroids, Mr.Kemp?...    Bill Higgins
Hundreds of thousands of them.  All
wandering around the Sun in strange        Fermilab
orbits.  Some never named, never
charted.  The orphans of the Solar         [e-mail]
System, Mr. Kemp."
                                           [e-mail]
"And you want to become a father."
  --*Moon Zero Two*                        SPAN/Hepnet: 43011::HIGGINS

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

Date: Tue, 16 Mar 1993 19:57:42 GMT
From: [e-mail]
Subject: Galileo HGA
Newsgroups: sci.space

Anyone have any clue as to what this "HGA receive pattern" test recently
was all about?  Do they have plans (or last-chance hopes) to use the HGA in
some degraded form, or is this just for contingency in case the LGAs die?

Burns

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

Date: 16 Mar 93 21:27:21 GMT
From: Thomas Clarke <[e-mail]>
Subject: Galileo HGA
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer)
writes:
>
> Note that since much of the original mission can be flown using the
> low-gain antenna, it is not permissible to endanger the spacecraft in
> an attempt to open the high-gain antenna.

You mean sideswiping an asteroid to try to knock the antenna loose is out :-)

--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

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

Date: 16 Mar 93 18:27:33 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: Just a little tap (was Re: Galileo HGA)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Thomas Clarke) writes:
> In article <[e-mail]> [e-mail] (Henry Spencer)
> writes:
>>
>> Note that since much of the original mission can be flown using the
>> low-gain antenna, it is not permissible to endanger the spacecraft in
>> an attempt to open the high-gain antenna.
>
> You mean sideswiping an asteroid to try to knock the antenna loose is out :-)

Hmm, they're going past Ida in August, and a zero-distance flyby is well
within the propellant margins, I'm sure...

The House Telecommunications Subcommittee  |
has scheduled a hearing on the issue for   | Bill Higgins
next Wednesday, featuring advocates of     | Fermilab
tougher regulation as well as Shari        | [e-mail]
Lewis, host of a children's show on public | [e-mail]
television, and her sock puppet Lamb Chop.  --*N.Y. Times*, 4 Mar 93, p. A9

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

Date: Tue, 16 Mar 1993 20:48:19 GMT
From: Dave Stephenson <[e-mail]>
Subject: Lunar Ice Transport
Newsgroups: sci.space

[e-mail] (fred j mccall 575-3539) writes:

>In <[e-mail]> [e-mail] (Pat) writes:

>>Fred talks about accuracy problems in Ballistic delivery due to masscons
>>and weight variations.

>>I imagine tha tthe  problem is not that difficult.

>>First, a highly accurate gravity map would be available,  and this
>>would be over a single well known route.

>I'm not convinced that such a map would be available.  Simply making
>such a map seems like quite an undertaking.

>>Second,  the moon is seismically dead, so it won't vary.

>>Third.  THere is no atmosphere to foul up flight.

>>I imagine loads would be weight and balance checked before launch,
>>and may even fly with an emergency trajectory correction package
>>for abort purposes.  i.e.  the gun loses power on the final 10%
>>of acceleration.

>The problem here is twofold.  Any variance in mass distribution of the
>load or of power and efficiency of the launcher are going to lead to a
>miss.  I think this is a more difficult problem over the distances
>being talked about than Pat seems to believe.  'Mere engineering',
>perhaps, but that makes it no more tractible.

>>Remember, using 18"  cannon,  in atmosphere,  the US navy had a regular
>>accuracy of 50 meters in 35 miles.

>The U.S. Navy has never had a ship mounting an 18" gun.  The Japanese
>had a few (Yamato, et al), but the largest gun on a U.S. ship was and
>is 16" on the New Jersey and Missouri BB's.  The range of a 16" gun is
>not 35 miles; It is around 40 kilometres or about 23 miles.  Note that
>this is not that far over the radar horizon, which is how reasonable
>accuracy is achieved.  Fire a shot that should be close, see where it
>lands, then make adjustments.

>Now do the triginometry to compute what a 50 metre error over a 40
>kilometre flight translates to when the range is on the order of 1/4
>of the lunar circumference.  The kind of accuracy needed over a flight
>of that length is *hard*; midcourse and terminal homing would seem to
>be required, unless your 'catcher' is something on the order of a
>crater that is lidded over with some sort of flexible 'valve' diaphram
>and you can just let the projectiles crash down anywhere within a
>circle a couple of hundred metres across -- and even then, it's not an
>*easy* problem.

>--
>"Insisting on perfect safety is for people who don't have the balls to live
> in the real world."   -- Mary Shafer, NASA Ames Dryden
>------------------------------------------------------------------------------
>[e-mail] - I don't speak for others and they don't speak for me.

The technology of billiant pebbles turned around and beefed up a bit
would be the sort of gudance that would be needed. In space what is moveing
and what is fixed is a matter of reference. A laser path way from the target
would help, after all it worked in desert storm!
--
Dave Stephenson
Geodetic Survey of Canada
Ottawa, Ontario, Canada
Internet: [e-mail]

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

Date: 16 Mar 93 20:46:00 GMT
From: SCOTT I CHASE <[e-mail]>
Subject: Mars Observer Update - 03/16/93
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Ron Baalke) writes...
>Forwarded from the Mars Observer Project
>
>                       MARS OBSERVER STATUS REPORT
>                              March 16, 1993
>
>The Flight Team reports that spacecraft subsystems and the instrument
>payload are performing well.  The spacecraft is in Array Normal Spin in
>outer cruise configuration, with uplink and downlink via the High Gain
>Antenna; uplink at 125 bps, downlink at the 2 K Engineering data rate.
>The DSN (Deep Space Network) is providing continuous coverage to Mars
>Observer in support of TCM-3 (Trajectory Correction Maneuver #3) activities.

Why are uplink and downlink at different data rates?  Does the spacecraft
have a better transmitter than receiver?  I presume that we can transmit
as well as we can receive, so that the difference must be due to some
spacecraft design issue.

-Scott
--------------------
Scott I. Chase            "It is not a simple life to be a single cell,
[e-mail]         although I have no right to say so, having
                 been a single cell so long ago myself that I
                 have no memory at all of that stage of my
                 life." - Lewis Thomas

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

Date: Tue, 16 Mar 1993 19:45:09 GMT
From: [e-mail]
Subject: NASA SELECT TV
Newsgroups: sci.space

In article <[e-mail]>,
[e-mail] (Dillon Pyron) writes:
|>Find sponsors.  I have three people that have indicated they will put in
|>$100/quarter in exchange for some minor mention.  Not much is needed since
|>the
|>dish is already pointed at the bird and the cable company doesn't have to

|>pay
|>for it.

Is this true?  Last time I tried to get a cable company to take NASA Select,
they said that there was nothing else they used on the same bird, so it would
take a whole new dish.  Has this changed.  Did they lie?

Burns

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

Date: Tue, 16 Mar 1993 22:40:20 GMT
From: Dillon Pyron <[e-mail]>
Subject: NASA SELECT TV
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] () writes:
>In article <[e-mail]>,
>[e-mail] (Dillon Pyron) writes:
>|>Find sponsors.  I have three people that have indicated they will put in
>|>$100/quarter in exchange for some minor mention.  Not much is needed since
>|>the
>|>dish is already pointed at the bird and the cable company doesn't have to
>|>pay
>|>for it.
>
>Is this true?  Last time I tried to get a cable company to take NASA Select,
>they said that there was nothing else they used on the same bird, so it would
>take a whole new dish.  Has this changed.  Did they lie?

It depends on your csble company and your location.
--
Dillon Pyron                      | The opinions expressed are those of the
TI/DSEG Lewisville VAX Support    | sender unless otherwise stated.
[phone] (when I'm here)     |
[phone] (when I'm home)     |Guns don't kill people, religious cults kill
[e-mail]          |people.  Ban religion, repeal the 1st
PADI DM-54909                     |Ammendment.  That's just as silly!

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

Date: 16 Mar 1993 21:05:45 GMT
From: Andy Cohen <[e-mail]>
Subject: Response to various attacks on SSF
Newsgroups: sci.space

In article <[e-mail]>, [e-mail]
(Mark Littlefield) wrote:
Lots deleted...

> .......  Requirements, documentation and management may not be
> the most romantic aspects of the space program, but without them,
> nothing will fly.


Heh-heh....tell that to both SSF AND DC-X teams!  I wonder if SSF will fly
just because we're bogged down in paper.  I was in a mtg yesterday when it
was stated and agreed to by all that the best approach on the table would
not work because it would take 1 year for the documentation of the approach
to get out to the entire SSF communitee......It's time to stop killing
trees and start flying systems.

A few months ago NASA stated that the contractors will create their own
integration team....the Joint Vehicle Integration Team or JVIT....  to be
headed up by whichever contractor was critical at that point in the
program....  The JVIT would have full authority over all mechanical design
integration issues with NASA still maintaining responsibility over avionics
integration (Level II)....  This all went (in the words of Arnold
Aldridge)..."On the shelf" after the announcements of yet another
redesign.....

At the end of each month, till the end of the 90 period, the Shea team is
to give a review of the work to date.  I would bet that we will see a BIG
drop in complexity and paper.....we have to or we won't fit within the $
limit....


17 more days till DC-X rollout......
20 days left till WP-02 CDR.............for the shelf......
83 days left to the redesign effort......

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

Date: Tue, 16 Mar 1993 21:20:31 GMT
From: Josh Hopkins <[e-mail]>
Subject: Without a Plan
Newsgroups: sci.space,talk.politics.space

>In <[e-mail]> [e-mail] (Nick Szabo) writes:

>>[e-mail] writes:

>>>In my opinion the space program has a fundamental problem that cannot be
>>>solved by Allen and I reaching for the jugular. The American space program
>>>today has no central, unifying sense of purpose.

>>Would that it were true.  The fact is that the obsolete, bizarrely
>>expensive religious sacraments of shuttle, space station and future
>>plans for "manned bases" still dominate the thinking and funding
>>of our civilian program, while producing practically no advance
>>towards anything useful, such as a sustainable human presence
>>in space or serving the needs of people on earth.

>I prefer sending people to sending toasters.  So do most taxpayers,
>given that alternative.  Why can't you justify what you want by
>justifying what you want rather than character assassination on those
>who disagree with you and negative attacks on what they want?

Seconded.  Ad hominem attacks don't accomplish anything.

>>Until we _lose_ the delusional, cultish cant of Wingo's, that our
>>vision must be one (his) and must never change, regardless of
>>changes in technology, politics, etc., NASA and space fans will
>>continue beating our heads against a brick wall.

Nick, Dennis was working on a tethered satellite system which, according to
Space News, is scheduled to launch this week with a total project cost of
$10 million to NASA.  It hardly seems effective to use him as the archetypal
paperpushing luddite astronaut groupie.

I certainly don't agree with everything he says but I haven't found him to be
any more set in his ways than you.

--
Josh Hopkins                                          [e-mail]
          "Tout ce qu'un homme est capable d'imaginer, d'autres hommes
                     seront capable de la realiser"
             -Jules Verne

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

End of Space Digest Volume 16 : Issue 324
------------------------------