Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_0/V10_057.TXT

Internet Message Format | 1991-07-08 | 16KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/sZ54=4600jaS09O052>;
          Sun, 17 Sep 89 21:20:04 -0400 (EDT)
Message-ID: <AZ54-gC00jaSA9ME4=@andrew.cmu.edu>
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sun, 17 Sep 89 21:19:40 -0400 (EDT)
Subject: SPACE Digest V10 #57

SPACE Digest                                      Volume 10 : Issue 57

Today's Topics:
           Re: Tracking Military Satellites
               Relayed message
             Re: Laser propulsion
         Re: What's Wrong With HR2674. (long)
           Re: Tracking Military Satellites
             Re: NASA missions/time table
        Re: Hurricane Gabriell GIF pictures from GEOS
                 Re: Galileo
               Re: Phone Tree Alert!!!
         Sagan's COSMOS series on videotape.
              Re: Neptune fly-by
----------------------------------------------------------------------

Date: 8 Sep 89 00:15:09 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Tracking Military Satellites

Workstation users, PLEASE keep your article line lengths < 80 columns.
Ultralong lines play havoc with many terminals of the mere mortal kind.
Remember, everything you WRITE someone has to READ.
--
Annex Canada now!  We need the room,    \)    Tom Neff
    and who's going to stop us.        (\    [e-mail]

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

Date: 8 Sep 89 01:45:58 GMT
From: [e-mail]  (Todd L. Masco)
Subject: Relayed message

This came to me (probably because I run the SPACE Digest), and I don't
know whether it reached anywhere else...

--
| Todd L. Masco        |  Quantum Mechanics: The dreams stuff is made of.
| [e-mail]  |     ( ...!harvard!andrew.cmu.edu!tm2b )
| [e-mail] |    SPACE Digest: [e-mail]
--
Hermann Schneider <[e-mail]> wrote:

 >From: [e-mail] (Stuart Warmink)
 >Subject: ESA news bulletins?
 >Date: 7 Aug 89 16:52:04 GMT
 >
 >If anybody in the European Space Agency is reading this, would it be
 >possible to post regular news bulletins (similar to Peter Yee's postings)
 >regarding the status of launchers and/or payloads?
 >
 >It is not easy to obtain up-to-date info on ESA on this side of the
 >Atlantic; I am sure I am not the only one who would be very interested
 >to read such reports!
 >--

 I asked our public relations office at ESA-HQ in Paris to put their
 press and news releases to this space list, but they seem not to be able
 to handle the computer! More than a year ago our public relations manager
 madame Beatrice Lacoste (BPLACOST@IFRESA10) was (probably is) member of
 this list. It may help, if many people write to her!

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

Date: 7 Sep 89 23:49:08 GMT
From: uhccux!munnari.oz.au!murtoa.cs.mu.oz.au!otc!metro!bunyip![e-mail]  (George Michaelson)
Subject: Re: Laser propulsion

[e-mail] (Henry Spencer) writes:

>In article <[e-mail]> [e-mail] (Jeff Berkowitz) writes:
>>What is the current status of "laser propulsion"?


>>The vehicle was to
>>be very small, of course - maybe a few pounds...

>You can build it most any size you want, except that the size (and price)
>of the laser and power supply goes up roughly linearly with payload size.

Linear is better than exponential, but not as good as you'd want.
If your looking for a comparison, Large ships (where surface area == drag is
the limiting factor (?)) would be a nice example, where larger is often more
economic (however that is for transport having to carry it's own fuel/engines)

As for increased laser SIZE surely the requirement is for increased
ENERGY at the point of "combustion" in which case banks of lasers might
suffice. Building many smaller lasers being (probably) more simple than
1 mega-huge one (again economy of scale & mass production), surely this means
size is not such a problem?

Multiple lasers have other benefits. Assuming some reasonably efficient
multiplexing/splitting mechanism at high powers is available you can tune
your "engine" to reflect 1 large or many simultaneous small payloads, launch
at different angles, vaporize congressional observers, cook breakfast etc etc.

    George

--
Internet: [e-mail]                     Phone: [phone]
  Postal: George Michaelson, Prentice Computer Centre
          Queensland University, St Lucia, QLD Australia 4067.

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

Date: 8 Sep 89 15:49:19 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Kieran A. Carroll)
Subject: Re: What's Wrong With HR2674. (long)

[e-mail] (6079 Smith James) writes:

>There are two problems with this reasoning:
>
>1.  High technology does not mean low cost.  The Space Shuttle, especially
>its main engines and heat-shielding, were cutting-edge technology back in
>the seventies.  The result is a temperamental system that has to be babied
>through everything.  Meanwhile, other low-tech launchers are going up
>regularly, even in rain and snow, because they are simpler and better
>understood.

High-tech does not >necessarily< mean low cost, certainly. High-tech
for the sake of high-tech is likely to raise costs. However, I have
yet to find anybody who believes that evolutionary changes to
conventional rockets could result in >extremely< low launch costs.
Laser launchers, on the other hand, might get launch costs down to
the $10-$100/kg range -- the point is to develop the technologies
that help you whittle away (or chop away) at costs, rather than those
that are just "sexy".

>2.  The starship fallacy again:  if you build one now, a better one will
>be available in time to beat it out, so why bother to build one now?

Because I'm selfish: I want this done during >my< lifetime! Better
yet, while I'm still young enough to benefit from it. Of course,
humankind will benefit as well, I believe to an enormous extent,
from >hastening< the reduction of launch costs.

>Let NASA do the unprofitable R&D, and let private enterprise build some
>off-the shelf launchers to get the hardware up.  Isn't that how our
>modified capitalism is supposed to work?...
>The point is, we have a research agency in place now.  If we relieve them
>of the responsibility of launching everybody's stuff, we will have *more*
>tech. advances and *more* launches without any gov't budget increases.
>
>Make sense?

Well, this is a suggestion worth considering -- using HR2674 to
make private enterprise in charge of launching things, and then
returning NASA to its role as a research and development agency.
A major justification for the "Space Mail" proposal is the success
of American aviation development in the middle decades of this
century, some of which is attributed to the "Air Mail" subsidies.
At that time, aircraft manufacture and operations were in the hands
of private companies, and NACA did R&D that benefited all such
users of aircraft. How much of the success of the industry was due to
the subsidies, and how much to the division of responsibilities?
Perhaps >both< were necessary, in which case by analogy we should
be pushing for >three< new bills: one to put launcher operations in
private hands (HR2674), one to revamp NASA to provide substantial
R&D support to such an industry, and one to implement a "Space Mail"
subsidy.

I think that my objections to HR2674 boil down to a feeling that
it doesn't go far enough, it doesn't do enough. It's only part
of a solution, and may be mistakenly perceived by Congressfolk as being
>all of< a solution. Unfortunately, making big changes in the structure
and operations of government is difficult -- I must admit that I can't
see all three of the proposed changes being pushed through at once,
not without some high-level support, or some other way for making
Congress-guys-and-gals see that the present system is not working,
and that it is important that it be fixed now.
--

     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [e-mail]

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

Date: 8 Sep 89 20:22:00 GMT
From: brutus.cs.uiuc.edu!wuarchive!csd4.csd.uwm.edu!uakari.primate.wisc.edu!pikes!udenva!isis!scicom![e-mail]  (Bruce Watson)
Subject: Re: Tracking Military Satellites

In article <1050400003@cdp>, [e-mail] writes:
>
> Tracking Military Satellites
>
> I would be very interested in learning of anyone tracking low altitude American Military satellites - those for which the Godda
> rd Satellite Situation Report lists "Current Elements Not Maintained." In particular, I am interested in obtaining orbital infor

The British Kettering group has unusual info on occasion and Amateur Satellite
Observers based in Arkansas is the only USA group that I know of; but
they both rely on NASA two-lines (furnished on this board by Dr. Kelso).

I've been interested in tracking these sats since they (and some old
spent booter stages--also not supplied by NASA) are among the brightest
visible objects with MIR, Salyut 7, and LDEF.

I've been working on programs using 3 positions and 3 times to determine
elements on surprise objects but the short arc for the low, bright ones
yields unsatisfactory results.  2 postion-2 time methods work about as
well.  Improvement methods using follow-on observations could be used to
improve the accuracy.  I'm still working on that.

Two large payloads were launched on DOD Shuttle missions and a Titan 3
from the Cape with 57 degree inclinations.  There are probably many
more bright ones to include.

Any observations of unknowns against the stellar background are welcome.
I'll see what I can do for anyone who wishes to submit visual
obsservations.

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

Date: 8 Sep 89 18:11:01 GMT
From: att!mcdchg!ddsw1!corpane![e-mail]  (John Sparks)
Subject: Re: NASA missions/time table

<[e-mail]>
Sender:
Reply-To: [e-mail] (John Sparks)
Followup-To:
Distribution:
Organization: Corpane Industries, Inc.
Keywords:


In article <[e-mail]> [e-mail] (Henry Spencer)
writes:
>In article <[e-mail]> [e-mail] (Ken Arromdee
(600.429)) writes:
>>>        12/08/1990 -- Galileo flies past Earth at an altitude of 620 miles.

>Incidentally, I'm told that if you think that Earth encounter is close,
>you should check out the Moon part of the encounter.  The number I heard
>was 75 miles.  (I have *not* checked this and my source might perhaps have
>been mistaken; I don't recall hearing about it before.)
>--

Y'know, with everyone complaining about polluting Jupiter with microbes and
with launching the Probe with so much plutonium aboard, I wonder if they will
complain about Galileo using Earth/Moon for a Gravity assist? I can hear them
now:

"It's using up our gravity"
"It'll slow us down. We could fall into the sun"
"The moon will fall on us now"

Conserve Our Gravity! Ban Galileo!

;-)
--
John Sparks   |  {rutgers|uunet}!ukma!corpane!sparks | D.I.S.K. 24hrs 1200bps
|||||||||||||||          [e-mail]         | 502/968-5401 thru -5406
You are in a maze of twisty little passages, all alike.


--
John Sparks   |  {rutgers|uunet}!ukma!corpane!sparks | D.I.S.K. 24hrs 1200bps
|||||||||||||||          [e-mail]         | 502/968-5401 thru -5406
You are in a maze of twisty little passages, all alike.

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

Date: 10 Sep 89 01:49:44 GMT
From: buengc![e-mail]  (Blair P. Houghton)
Subject: Re: Hurricane Gabriell GIF pictures from GEOS

In article <[e-mail]> [e-mail] (Phil Howard) writes:
>Current GEOS weather satellite images showing Hurricane Gabriell and other
>weather activity in GIF format are being placed online for anonymous FTP
>access.
>
>host:       vmd.cso.uiuc.edu (128.174.5.98)
>user:       anonymous
>pass:       -none-
>cd/cwd:     phil.515

But is she naked?

                --Blair
                  "And just what IS this 'blif'
                   thing?"

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

Date: 11 Sep 89 01:33:26 GMT
From: cs.utexas.edu!ut-emx!walt.cc.utexas.edu![e-mail]  (Feulner ... Matthew Feulner)
Subject: Re: Galileo

In article <[e-mail]> [e-mail] (Tom Neff) writes:
>
>With Galileo I am more concerned about the sheer number of gravity
>assists than I am about the choice of targets.  Each flyby carries a
>nontrivial risk of mission failure.  On the other hand each offers
>science benefits.  A shame they can't toss Mars in with Venus and Earth
>for a sort of "Petit Tour." :-)

I don't consider 3 a "sheer" number.  Voyager II had 3 at much larger
distances.  Also, they all are necessary to get to Jupiter at all.
If you are worried about mission failure (rather than Gaileo crashing
into the earth), you're better off worrying about the fly-bys of
Jupiter's moons.

Matthew

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

Date: 11 Sep 89 15:26:56 GMT
From: deimos.cis.ksu.edu!cveg!hcx![e-mail]  (6079 Smith James)
Subject: Re: Phone Tree Alert!!!


In article <1050400008@cdp>, [e-mail] writes:
>   The President's budget request was for approximately $4.4
> million, which was cut in the House appropriations committee by $800,000 to
> $3.6 million. While not a lot compared to other space projects, this cut
> represents the loss of 2 staff positions in a 12 person office, and
> deferral of study contracts on safety issues with the Hawaii and Florida
> commercial spaceport efforts. The cuts may also slow the processing of
> license application for commercial launches.

If that's all we get for $800,000, maybe we need to cut more from these
guys.  Sounds to me like we're paying a bundle for more useless bean-
counting and paper-shuffling.  I bet Norman Kluksdahl could build his
model aerospace plane for $800,000.


|  James W. Smith, University of Arkansas  |  hcx![e-mail]   |
|------------------------------------...uunet!ksuvax1.cis.ksu.edu!hcx!jws3 --|
|    I'm so depressed.  If I didn't have so much to do, I'd be a nihilist.   |

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

Date: 11 Sep 89 22:26:41 GMT
From: wrksys.dec.com![e-mail]  (CUP/ASG, MLO5-2/G1 6A, 223-3283 11-Sep-1989 1755)
Subject: Sagan's COSMOS series on videotape.


        All thirteen episodes of Carl Sagan's COSMOS series as they were
    originally broadcast on PBS-TV in 1980 will be made available on
    videocassette by Turner Home Systems before the end of this year.
    No specific dates or prices were announced.

        Larry Klaes  [e-mail]
             or - ...!decwrl!wrksys.dec.com!klaes
                 or - [e-mail]
                     or - [e-mail]

        EJASA Editor, Astronomical Society of the Atlantic

             N = R*fgfpneflfifaL

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

Date: 12 Sep 89 13:09:41 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Neptune fly-by

In article <[e-mail]> [e-mail] (John E Van Deusen III) writes:
>Oh well, the aliens probably took their phonograph record right away,
>and all of this has just been a fictional emulation created for our
>amusement.

This suggests a reason why the aliens haven't come to visit.

They're afraid we're one of those RECORD CLUBS!  "Agree to buy only five
more disks..."
--
Annex Canada now!  We need the room,    \)    Tom Neff
    and who's going to stop us.        (\    [e-mail]

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

End of SPACE Digest V10 #57
*******************