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Subject: SPACE Digest V10 #19

SPACE Digest                                      Volume 10 : Issue 19

Today's Topics:
             Space Law Symposium
       Re: NASA Headline News for 08/29/89 (Forwarded)
               Re: Voyager Pics
    Another Voyager task (was Re: Voyager Interstellar Trajectory)
           Re: Voyager/NASA Spacelink BBS ?
        Let's do what THEY say is impossible.
      Re: Where the hell are electric-ion thrusters????
           Where to look for Martian 'Face'
      Re: Where the hell are electric-ion thrusters????
             RE: Satellite lists
               Shuttle Flight Sequence
      Re: Where the hell are electric-ion thrusters????
----------------------------------------------------------------------

Date: 30 Aug 89 02:26:45 GMT
From: intercon![e-mail]  (Mikki Barry)
Subject: Space Law Symposium

The First Annual Space Law Symposium will be held September 8-9 at the Georgetown
University Law Center on New Jersey Avenue in Washington, DC.  Many distinguished
(or so they claim) speakers will be on hand to discuss current developments
in outer space law.  Guess those damn lawyers have their fingers into
everything :-)

If anyone wishes further information, please E-mail me.  I mean, like WOW!
Dan Quayle sent us a letter praising our great effort in organizing and helping
to present this symposium.  What better guy could you have pulling for you?
I wonder who wrote the letter for him :-)

Proceedings will be published in October (hopefully) in the Journal of Law
and Technology published at Georgetown.  Projected cost is about $10.00 each.
Anyone interested in ordering it (much cheaper than the $70 admission charge
for both days) can also contact me and I'll put your name on the list.

Mikki Barry
Junior Litigator (Hark, is that an ambulance I hear?)
Georgetown University Law Center
Journal of Law and Technology

--

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

Date: 29 Aug 89 18:00:00 GMT
From: phoenix!puppsr![e-mail]  (marty ryba)
Subject: Re: NASA Headline News for 08/29/89 (Forwarded)

[e-mail] (Peter E. Yee) writes:

>-----------------------------------------------------------------
>                           NASA Headline News
>Tuesday, August 29, 1989                       Audio:202-755-1788
>-----------------------------------------------------------------

>This is NASA Headline News for Tuesday, August 29..........

>Two Cornell University astronomers announced that they have
>discovered a galaxy in the making.  The giant hydrogen cloud was
>accidentally found by the pair last spring while they adjusted
>the giant optical telescope at an observatory in Arecibo, Puerto
           ^^^^^^^
It's a *radio* telescope, dammit!!!!!!!!!!

>Rico.  The galaxy, which is said to be ten times larger than the
>Milky Way, contains no stars and is not visible by optical
>telescopes.  Rather, the hydrogen cloud produces radio signals
>like those that would be emitted if a galaxy were there.
>Astronomers will not be able to verify the existence of the
>possible galaxy until next spring when it should again be
>detectable from Earth.

>---------------------------------------------------------------
>These reports are filed daily Monday through Friday at 12 noon,
>Eastern time.
>---------------------------------------------------------------

>A service of the Internal Communications Branch, (LPC), NASA
>Headquarters.

I hope this kind of screw-up isn't indicative of the quality of people they
use for PR!

I know the people involved (Riccardo Giovannelli and Martha Haynes).  They
are very much radioastronomy types; the 300-m Arecibo radiotelescope is a
wonderful instrument (I use it constantly) that I feel gets too little respect.
(flame off -- thrrrrrup!) :-)

Marty Ryba (slave physics grad student)
They don't care if I exist, let alone what my opinions are!
[e-mail]
Asbestos gloves always on when reading mail

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

Date: 29 Aug 89 20:33:56 GMT
From: [e-mail]  (Adam Glass)
Subject: Re: Voyager Pics

[e-mail] (Usenet file owner) writes:
> So, does anybody know when these fabulous pics of neptune will be
> available in sun workstation format, or in .GIF format?

Someone posted a message that lots of GIF's (including the latest
neptute and triton pictures) from their machine. I think it was
grape.ecs.clarkson.edu. Anyway, I ftp's there and went into binary
mode and got a bunch of pics. But when I ftp's them down to the mac
(I was in binary this time, too), it (Vision Lab) either opens a
solid black screen (i.e., pictures mapped to an apparently-synthesized
all-black CLUT) or it complains about bad LZW codes or early EOF's.
The bottom line: the GIF's are either corrupted or I'm doing something
wrong. I'd like to believe it's the second thing, but since I've tried
numerous ways of doing this, I'm afraid that it might be the first
(though I find this hard to believe).

Would someone (perhaps the person whose machine this is) care to
enlighten us about what format it is/how we shoulf ftp it/anything
else which is important...?

Adam
--
"He didn't fall? Inconceivable!"  Internet email: [e-mail]
"You keep using that word... I do not think it means what you think it means."
(All stolen quotes taken from The Princess Bride) Hmm... 18 spaces left. Moof!

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

Date: 29 Aug 89 19:25:53 GMT
From: encore!xylogics![e-mail]  (Jim Barnes)
Subject: Another Voyager task (was Re: Voyager Interstellar Trajectory)

In article <[e-mail]> [e-mail] (Daniel P. Barron) writes:

>Of course, WHYY took the oppurtunity to interrupt every 20 minutes to tell
>you that "you can become part of history by calling 1-800-228-1234 and
>pledging your support to channel 12!"
>

WGBH in Boston went one further by saying something to the effect that
you could call 492-1111 anytime.  So, if you taped the show and were
just now watching the program, you could still call and donate money.

On a subject closer to the original posting, I heard some suggestion
(speculation?) that the Voyager camera might be used once more to take
a picture of the entire solar system when Voyager had travelled far
enough away.  Can anyone out there provide any details?  Would such
an image be able to show the planets or would everything be overpowered
by the sun?  How far away would Voyager have to be to allow all the
planets to be in the same image?  (Or, could they use a series of
images as was done for the closeups of the satellites/planets?)  How
long would it take Voyager to get to a position to get a good perspective?
(I assume that Voyager is now moving out of the orbital plane of the
planets.)



----
  Jim Barnes ([e-mail])

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

Date: 30 Aug 89 00:26:35 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Voyager/NASA Spacelink BBS ?

In article <[e-mail]> [e-mail] (Ray Smith) writes:
>Unlike bulletin board systems, NASA Spacelink does not provide for
>interaction between callers.  However, it allows teachers and other
>callers to leave questions and comments for NASA.

That is, it did until the number was posted to 100,000 net readers.


--
"We walked on the moon --    ((    Tom Neff
    you be polite"         ))     [e-mail]

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

Date: 29 Aug 89 14:32:06 GMT
From: tank!shamash!com50!questar![e-mail]  (Al Viall)
Subject: Let's do what THEY say is impossible.

ENOUGH is ENOUGH!!!
If you are a type of person, like me, who gets ticked off at the total
lack of prestige and adventurism shown by this Administration, and the
chaotic bungling of planning by this country's Space Administration; I say,
let's kick it in the rear and do it ourselves.
I've got to hand it to Henry Spencer, he's got charisma; to dare to do what
NASA hasn't been able to do for over 20 years, it's a great idea.
I am fed up with hearing about new funding for weapons we don't need, at
a cost we can't afford, and at a quality paralleling that of a taiwanese
lighter most of us find in a skillcrane at the State Fair.
I am tired of empty promises by the dynamic duo in Washington, of funding
for space exploration, when we all know the real sentiment behind the
gestures.
So, here is a solution. <--- Heh!
Let's form a coalition, funded by such renowned meglomaniacal billionaire's,
such as good old Don Trump, and just do it ourselves.
Given the variety of skills, just on this NET, we could probably have our
own Space Station up in less than five years.
I'm sure Donald Trump would go for this. After all, we could paint
'TRUMP STATION' in red, white and blue letters across the side.

(Al)
It was just a thought.....

--
 | Albert Viall                     |   EMAIL:[e-mail] |
  | ARPA: [e-mail]  |   FIDONET: 1:242/2                |
  |   "Uhh, Excuse me while I take a moment to adjust my tribble."       |
  ------------------------------------------------------------------------

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

Date: 29 Aug 89 12:48:37 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: Where the hell are electric-ion thrusters????

In article <[e-mail]> [e-mail] (Terry Hancock) writes:

>    It uses electrostatically accelerated mercury (cesium would
>by bad news, by the way, it's both very reactive, and radioactive),
                           ^^^^^^^^^^^^^^^
>mercury will just give you heavy metal poisoning if you ingest it.

I don't know what planet you're from, but here on Earth cesium
occurs naturally as Cs-133, which is most certainly *not* radioactive.

A reason to use mercury is its higher atomic mass.  This means that
(for the same ionic charge) you can use a higher voltage to reach the
same exhaust velocity.  Higher voltages are good because current
density through an ion engine is limited by space charge effects, and
this limit is strongly dependent on voltage (assuming constant
separation between the accelerating grids).  The more current, and the
higher the atomic mass, the higher the thrust per unit engine area.

>    50 lbs thrust is TOTAL B.S.  for an (electrostatic) ion drive,
>certainly any one tested.  The specifications for the 30-cm are:

Perhaps he was thinking of a magnetoplasmadynamic (MPD) engine.

>    The cost effectiveness of this depends also on the expense of
>mercury (anyone know what Hg costs?), which ought to be fairly rare,
>given its atomic weight (>Fe).  Probably cheaper to use kilos of Hg
>than kilotonnes of hydrogen, though.

Looking in an issue of the NY Times I had sitting around, I find that
mercury was listed at $275 for a 76 pound flask (look on the
commodities page), or about $3.62/lb.  In other words, the cost of
putting the mercury into orbit is about a thousand times the cost of
the mercury itself.

    Paul F. Dietz
    [e-mail]

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

Date: Tue, 29 Aug 89 11:25:16 PDT
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
Subject: Where to look for Martian 'Face'

In SD vol 10 #1 Dannie Gregorie complained of not being able to find any
pictures of the Martian "face".  The earliest publication of the "face" I've
found is in "Science News" August 7, 1976 p. 85 just after the first Viking
landing.  They ran it along with a quote from Harold Marsurky, one of the
project directors, saying this must be the guy who built all the canals.
So much for the idea that NASA and JPL tried to suppress the picture and
that it only came to light through the work of Hoagland et al.

In vol 10 #2 Nicheal Cramer suggested folks check out Ted Schultz's ook
_The Fringes of Reason_ and I heartily endorse that idea.  If you know a
bright 15 or 50 year old who is starting to get a bit deep on this kind of
stuff, do them a favor and get them a copy of this book.  It's put out by
_The Whole Earth Catalog_ folks (and no one can ever accuse THEM of being
a bunch of "closed minded left brain types") and is a wonderfully witty
and informed examination of current fringe science and beliefs.

As for me, I'm still waiting to find out more about that wonderful discovery
by the Russian spaceprobe that took photos of Heaven near Pluto (as reported
last year in the reputable scientific journal "World Weekly News")  :^)

Marc Hairston--Center for Space Sciences--UT-Dallas
SPAN address  UTSPAN::UTADNX::UTD750::HAIRSTON

"There's a difference between having an open mind and having one so open
that you can pour water through it."

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

Date: 29 Aug 89 18:19:41 GMT
From: vsi1!daver!lynx![e-mail]  (Neal Woodall)
Subject: Re: Where the hell are electric-ion thrusters????

In article <[e-mail]> [e-mail] (Terry Hancock) writes:

>The most powerful Ion drive designed and built (to my
>knowledge) is the 30-centimeter-diameter thruster developed at
>NASA Lewis Research Center:
>It uses electrostatically accelerated mercury (cesium would
>by bad news, by the way, it's both very reactive, and radioactive),
>mercury will just give you heavy metal poisoning if you ingest it.

Any reason why the eletric-ion thruster must use mercury as the
reaction mass? Is it possible to develop a thruster that would
use a less expensive and dangerous material for reaction mass?
Is mercury used simply because it has a high atomic weight?







Neal

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

Date:     Tue, 29 Aug 89 12:26 EST
From: <[e-mail]>
Subject:  RE: Satellite lists

        Sorry if this appears twice - it seemed to disappear the first time.

        When various people gave their lists of satellites, I noticed
that none of the included references contained

   "The R.A.E. Table of Earth Satellites:1957-1982", 1983, John Wiley & Sons.

While not as simple to find something, because it lists every item sent
into space separately, it does seem to be complete.  Does anyone know if
this book has been updated since the 1983 edition?

 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
|  Arnold Gill                          |
|  Queen's University at Kingston       |
|  BITNET:    gill@qucdnast             |
|  INTERNET:  [e-mail]  |
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Date: Tue, 29 Aug 89 09:55:18 PST
From: Peter Scott <[e-mail]>
Subject: Shuttle Flight Sequence
X-Vms-Mail-To: EXOS%"[e-mail]"

From _NASA Activities_, June 1989:

NASA has announced the order of planned Space Shuttle flights between
the Galileo mission to Jupiter and the Astro Spacelab mission.

After the Galileo mission, currently manifested for October 12, 1989,
the sequence of flights will be: the DoD mission, previously delayed
to "protect" the Galileo launch window; the Syncom IV deployment/LDEF
retrieval mission; a DoD mission; the Hubble Space Telescope mission;
and the Astro mission.

NASA management decided to fly only one mission between Magellan and
Galileo to be as certain as possible that the Shuttle program would
be ready to launch Galileo early in its planetary window.

Peter Scott ([e-mail])

Atmospheric content of Neptune: Ammonia, methane, hydrogen sulfide.
Obviously the Neptunians became extinct through terminal flatulence.

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

Date: 29 Aug 89 16:39:42 GMT
From: agate!bionet!csd4.csd.uwm.edu!mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Where the hell are electric-ion thrusters????

In article <[e-mail]> [e-mail] (Terry Hancock) writes:
>* I would like to take this opportunity to rag on the engineer who
>decided to cancel 1 lbf with 1 lbm and thereby arrive at seconds as
>the unit of Specific Impulse...

Perfectly legitimate cancellation; the problem is that the *unit* is
silly.  Use exhaust velocity instead -- not only is it expressed in
sensible units, it's physically meaningful to boot.
--
V7 /bin/mail source: 554 lines.|     Henry Spencer at U of Toronto Zoology
1989 X.400 specs: 2200+ pages. | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V10 #19
*******************