Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_4/V12_447.TXT

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Date: Fri, 12 Oct 1990 02:00:36 -0400 (EDT)
Subject: SPACE Digest V12 #447

SPACE Digest                                     Volume 12 : Issue 447

Today's Topics:
                Re: Space GIFs
              grad programs in robotics
              Nuke Waste Where?!
            Re: Manned/unmanned tradeoffs
            Re: Manned/unmanned tradeoffs
            Re: Manned/unmanned tradeoffs
            Re: Magellan Update - 10/09/90
                 Space Sails
             Re: shuttle pictures
               NASA TV Channel
            Wanted: GIF of Solar Eclipse.
             Pioneer 11 Update - 10/11/90

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 9 Oct 90 07:31:56 GMT
From: sumax!polari![e-mail]  (Don Wennick)
Subject: Re: Space GIFs

In article <[e-mail]> you write:
>Since my orriginal request for a source of space related GIF format pictures,
>there has been mail sent to me by others interested in the same thing.

Following is a response I recieved from a local user.  I've fowarded it in
hopes it will help others who seek the same information as myself.

There is an e-mail ftp server that I use occasionally. This allows access to
any anonymous ftp site, or any other ftp site you have a valid account
on. wuarchive.wustl.edu is accessible this way. The server's address
is [e-mail], and you can get the instructions for it's
use by sending e-mail with the command 'help' in the message body.
I don't know if a .signature will confuse it, but I never allow mush to
sign my messages to any servers.

Don.

---
Don Wennick | [e-mail] -or- [e-mail]
"subhuman bloodless leaders fed on lies and fear / and TV anchor news teams
 trim all we see and hear / use your head / sidestep the traps / snake
 through the chaos with a smooth noodle map" - Devo

-PV-
     /+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+\
     +   COMMENTS COMPLIMENTS CONTINOUS COMPLAINTS   +
     "             COURTESY: Paul Varn               "
     +   UUCP: pv@polari             GEnie: p.varn   +
     \+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+/

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

Date: 11 Oct 90 02:23:23 GMT
From: usc!cs.utexas.edu!sun-barr!ccut!wnoc-tyo-news!astemgw!choshi!frf![e-mail]  (Raymond Tang)
Subject: grad programs in robotics

Can any out there offer me some advice on graduate schools in the
field of Aerospace robotics.  Questions I have are: where to apply,
what is life like there, how many place to apply to, and any details
you have about the program.  Any other info you have will be greatly
appreciated.
Thanks in advance.......

                    Ray Tang
                    [e-mail]
please reply by email since I dont get the full sci.space feed.

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

Date: 2 Oct 90 14:29:00 GMT
From: sgi!cdp![e-mail]
Subject: Nuke Waste Where?!


I have read with great interest the discussion on this list of
proposals to shoot nuclear waste into outer space.  While I have
the greatest respect for those who have devoted themselves to the
mathematics of celestial navigation to achieve the requisite
orbits, I must question the political feasibility of this
proposal.  There are two MAJOR problems.  The first is the
unconsolidated nature of the waste.  Excluding spent fuel
assemblies, much of the so-called nuclear waste is just that -
garbage.  The problem is one of retrieval from covered landfills
such as the radioactive waste management complex at INEL.  It
includes contaminated machine parts, tools, waste rags, oil,
etc.  The second is getting the waste to the spaceport.  Readers
of this list need only inquire on BIOSPH-L@UBVM to get a
refreshing blast of the "not in my backyard" or NIMBY syndrone
which is so strong it has even defeated proposals for seaports to
load waste oil and pesticides for burning at sea.  Simply put,
the public is not interested in risk communication.  It will look
at the possibility of an abortive launch that distributes the
payload across their lawns not as a probability, but as
inevitable.

* -------------------------------------------------------------
* Dan Yurman   PO Box 1569, Idaho Falls, Idaho 83403 | 43N 112W
* Econet       [e-mail]                      |
* Internet     cdp![e-mail]       | Honor
* Bitnet       cdp!dyurman%labrea@stanford           | Before
* MCI          364-1277  or  [e-mail]     | Elegance
* -------------------------------------------------------------

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

Date: 4 Oct 90 01:41:39 GMT
From: elroy.jpl.nasa.gov!jpl-devvax![e-mail]  (Steve Jenkins)
Subject: Re: Manned/unmanned tradeoffs

In article <[e-mail]> [e-mail] (Marvin Minsky) writes:
>This is confusing different things.  Presumably, you could fly an
>F-16, in spite of delay -- if you could maintain low speeds.  You
>can't, because of gravity.  The problem of "real-time control", here
>is not involved with how FAST you can accelerate, but with how low you
>can keep your -- and how SLOW you can accelerate.  The issues about
>time delay are, thus, much more involved with speeds rather than
>accelerations.  Planes have minimum speeds, hence each delay implies a
>minimum reaction-distance.  But that has little to do with spaceships,
>or earth-ships.  Tankers can be "flown" as slow as you want, hence
>have no problems with time delay, for well-trained pilots.

I don't think we disagree, except that what you call "time delay" is
slow process dynamics, at least in the case of the tanker.  Tankers
have essentially no time delay on that scale.

Yes, you can accomodate time delays if your process dynamics are
sufficiently slow.  To some extent you can control that (fly slower, as
you suggest).  There are some things you can't control, though, and
they are the problem.  How fast a robot will fall over when tipped, for
example (returning to teleoperation).  If the robot's attitude control
system has appreciable time delays (light round-trip to earth) in its
feedback loop, it will have a very hard time staying upright if it
steps into a hole, or springs a gas leak, or is nudged by a
comrade....

This is what makes teleoperation hard.  You have to make sure that
nothing, including errors or random disturbances, forces your system at
rates for which the time delay is destabilizing.  The way you go about
it is to make the system more autonomous, removing the time delays that
cause problems.  The more autonomous it is, the less "teleoperated" it
is.  More like "teledelegated".

--
Steve Jenkins N6UNI            [e-mail]
Caltech/Jet Propulsion Laboratory    [phone]

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

Date: 4 Oct 90 03:11:30 GMT
From: media-lab![e-mail]  (Marvin Minsky)
Subject: Re: Manned/unmanned tradeoffs



At last we're getting somewhere.  [e-mail]
(Steve Jenkins) writes:

> Yes, you can accomodate time delays if your process dynamics are
sufficiently slow.  To some extent you can control that (fly slower,
as you suggest).  There are some things you can't control, though, and
they are the problem.  How fast a robot will fall over when tipped,
for example (returning to teleoperation).  If the robot's attitude
control system has appreciable time delays (light round-trip to earth)
in its feedback loop, it will have a very hard time staying upright if
it steps into a hole, or springs a gas leak, or is nudged by a
comrade....

Yes, I absolutely agree.  It is always possible for as telerobot -- or
a person -- to flip something too fast for the same system to catch.
That's life, and you have to be careful.  But I don't see why there is
any special problem in staying upright in space, for a telerobot.  If
it moves slowly enough, it should be able ton recover.  If not, you
should have carefully tethered it before you did anything risky.  And
so on.  Remember that humans have reaction times of 200 milliseconds,
so with a 1-second control loop to GEO, you should be doing everything
5 times slower -- at 1/500 the cost, according to my IMHO estimates.

> This is what makes teleoperation hard.  You have to make sure that
nothing, including errors or random disturbances, forces your system
at rates for which the time delay is destabilizing.  The way you go
about it is to make the system more autonomous, removing the time
delays that cause problems.  The more autonomous it is, the less
"teleoperated" it is.  More like "teledelegated".

Yes and No!  So far as I can see, this is absoultely right -- but
remember that all those problems are solved simply by proceeding 5 to
10 times slower, for GEO.  AND THIS IS WHAT MAKES TELEOPERATION SO
EASY.  Because there is no gravity, you can require that everything
actually proceed, say, 20 times slower!  Then, in effect, your
remote-astronauts can act as though they are 4 times faster than
people!!!!!!!!!

I can't understand why our entire civilization can't do this kind of
reasoning.  I have an idea.  Please, folks, instead of re-re-repeating
those misconceptions, help me understand why no one is willing to do
the elementary arithmetic involved.  When they introduced tankers and
construction cranes, was there the same universal disbelief?

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

Date: 5 Oct 90 17:59:07 GMT
From: sdd.hp.com!samsung!noose.ecn.purdue.edu!mentor.cc.purdue.edu!l.cc.purdue.edu![e-mail]  (Herman Rubin)
Subject: Re: Manned/unmanned tradeoffs

In article <[e-mail]>, [e-mail] (Ronald G Minnich) writes:
>
| > In article <[e-mail]>
> [e-mail] (Doug Mohney) writes:
| >I thought you ran into problems if things started to go screwy (such as trying
| >to compensate for a problem which happened 2.5 seconds ago, like
> falling into a
| >trench...).

> Try to run a long freight train sometime. The reaction time is measured in
> some cases in minutes. Or a supertanker. People in all walks of life are
> quite used to dealing with long reaction time environments. They learn to
> anticipate. I can't see any real problem with the 2.5s environment.

One does not run a long freight train or a supertanker in unexplored
territory.  Where there is long reaction time, the environment is usually
carefully controlled.

It might be possible to use earth-controlled waldos on the moon with a
2.5 second delay.  It would not on Mars with a 10-30 minute delay.
--
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: [phone]
[e-mail] (Internet, bitnet)    {purdue,pur-ee}!l.cc!cik(UUCP)

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

Date: 9 Oct 90 21:08:32 GMT
From: [e-mail]  (Jose A. Castanos)
Subject: Re: Magellan Update - 10/09/90

In article <[e-mail]>, [e-mail] (Sandi Piazza) writes:
> >
> >      The Magellan spacecraft has now completed 177 mapping orbits of Venus,
> > with good radar data recieved from at least 173 orbits.  Spacecraft systems
>
>   This is probably a dumb question, but I'll ask anyway.  What is going to
>   be done about getting the information missed in the 4 orbits for which
>   there was no good data received?

    I read in a posting in sci.space.shuttle that any gaps left after
    the primary mission (243 days - 1 Venus year) ends will be mapped in
    subsequent cycles.  During the second and third cycles, the south
    polar region (not covered by the first cycle) will also be mapped.
        There are various ideas for later cycles:

             * Remapping possibly-active areas to look for changes.

         * Stereo imaging by mapping interesting areas from more than
        one angle.

                    Jose A. Castanos
                    [e-mail]

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

Date: 5 Oct 90 07:08:17 GMT
From: psuvm![e-mail]
Subject: Space Sails

Dose anyone know the current condition of the Columbus 500 Space Sail race to
Mars?  I was on the design team for the promotional video for the race, and
we haven't heard anything recently.  I think that funding was finally assigned
to the design from the World Space Foundation, but that's it.  If anyone knows
the current status could you please send me some e-mail?  Thanks,

                                            Paul Wilson
                                            PRW102 @ PSUVM.PSU.EDU

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

Date: 5 Oct 90 15:07:50 GMT
From: snorkelwacker!mintaka!spdcc!ima!haddock![e-mail]  (overhead)
Subject: Re: shuttle pictures

In article <[e-mail]> [e-mail] (Red Roger) writes:
>    I was wondering if anyone has any pictures of the space shuttle in
>    GIF format that would be available for ftp ??
>    It wopuld make a great backdrop for an X screen to say have something
>    like the shot of the shuttle landing flanked by a couple of hornets.

wuarchive.wustl.edu has a real nice archive available via ftp.  I
forget the exact path, but "graphics" or "gif" or both are in it.
There are directories a-z and symbols.  Under "d", there is
"discovery".  I've also seen this with the file name
"space-shuttle-on-pad".  It is a nice 640x480 8 bit color shot.
There are also smaller pictures with shuttles in flight.  There
is a Hubble archive somewhere that has a series of pictures
obtained via frame-grabbing.  Not as many dots, and some of them
could use some work, but there are shuttle launch and landing
shots.  I don't know off hand where the hubble stuff is.  I've
seen a bitmap of a shuttle carried by the 747 shuttle carrier.
This is probably in the bitmap archive at MIT somewhere.

Stephen Uitti
[e-mail]

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

Date: 6 Oct 90 22:22:00 GMT
From: swrinde!zaphod.mps.ohio-state.edu!samsung!olivea!oliveb!felix!dhw68k!ofa123![e-mail]  (Carl Cason)
Subject: NASA TV Channel

I regret that I do not remember the name of the person who left the
message a couple weeks ago about Paragon Cable carrying (on channel 52
in the South Bay) the official NASA TV channel, but I want to give you a
belated "thank you."

It was a pleasure today to watch the shuttle launch and to check back
several times during the day to check progress.  To hear *all* the voice
transmissions between control and the shuttle was very interesting, and
I enjoyed being able to choose what I wanted to see and hear, not what
the networks thinks I might want to see or hear.

I also wrote a letter to Paragaon today thanking them for carrying the
channel.

Carl.

... The El Segundo Kid
--- Via Silver Xpress V2.27
 * Origin: Compu-Mart Mall -- Send me netmail to put one on YOUR BBS!!
(1:102/134)



--
Carl Cason
Internet: [e-mail]
--------------------------------------------------------------------------

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

Date: 11 Oct 90 00:00:12 GMT
From: sdd.hp.com!samsung!munnari.oz.au!metro!grivel!gara![e-mail]  (Philip Nettleton)
Subject: Wanted: GIF of Solar Eclipse.

Has anyone out there got a GIF picture of an Solar Eclipse which is
in the Public Domain? Any help would be appreciated. Thanks in advance.

                            Philip Nettleton.

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

Date: 11 Oct 90 15:32:18 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Pioneer 11 Update - 10/11/90


                        Pioneer 11 Update
                        October 11, 1990

     A spacecraft emergency was declared for the Pioneer 11 spaceraft at
3PM (PDT) on October 10.  The 70 meter tracking station in Goldstone supported
the emergency yesterday and today using its high power transmitter at 80 KW.
The 70 meter antenna in Australia observed downlink from Pioneer 11 this
morning, and the downlink was observed 1-way and locking at intervals of
3 to 4 seconds.  The longest period of receiver lock as reported at 20
seconds.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

End of SPACE Digest V12 #447
*******************