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Subject: SPACE Digest V10 #344

SPACE Digest                                     Volume 10 : Issue 344

Today's Topics:
         NASA Headline News for 12/13/89 (Forwarded)
                 Re: Motives
         Re: proposed "space-mail" incentive
               Re: Mars rovers
            Re: Non-autonomous Mars Rover
      Re: Relative distances and sizes in the Universe.
               Galileo Update 12/13/89
            ADDITION TO SUBSCRIPTION LIST
----------------------------------------------------------------------

Date: 13 Dec 89 19:45:10 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 12/13/89 (Forwarded)

-----------------------------------------------------------------
Wednesday, December 13, 1989                  Audio: 202/755-1788
-----------------------------------------------------------------


This is NASA Headline News for Wednesday, December 13....


The STS-32 space shuttle mission has been delayed until
Wednesday, December 20.   Extra time is needed to validate
systems at Launch Pad 39A and prepare Columbia for the flight.
The schedule remains very tight and there is the possibility lift
off could slip to the next day.  Associate Administrator for
Space Flight William Lenoir says he's confident there will be a
pre-Chirstmas lift off.


Preparations are underway for the second captive flight of the
Pegasus air launched space booster Thursday morning.  During the
flight a NASA B-52 will carry the 50-foot long winged booster to
an altitude of 41,000 feet over the Pacific Ocean 50 miles off
the California coast.  If all goes well...the first flight test
of the Pegasus will be as early as mid-January.  The booster will
carry a DoD and a NASA experimental payload.  NASA Select TV is
scheduled to provide coverage of the flight beginning at 10:00
A.M., Eastern time.


Space News says a Japanese firm has purchased a backup Mir space
station from the Soviet Union for $10 million.  The Horie Group,
a private trading firm dealing in space technology, says the Mir
station and accompanying Kvant module will be marketed to
Japanese commercial space interests for future projects.  There
is no immediate plan to launch the station which had been on
display in Japan for several months earlier this year.


Dr. Dale Compton has been named director of NASA's Ames Research
Center at Mountain View, Calif.  Compton assumes the position
December 20.  Compton, who has been serving as Acting Director,
succeeds Dr. William Ballhaus.  Compton has spent his entire
professional career at the Ames center.


Three commercial communication satellites may soon be shipped to
China for eventual launch aboard Chinese space boosters.  The
spacecraft had been included in an embargo of high tech and
military equipment following the freedom demonstrations in
Beijing last August.  Two of the satellites are owned by the
Asiasat consortium...the third by a British-Chinese Hong Kong
consortium.

             *            *             *           *



-----------------------------------------------------------------
Here's the broadcast schedule for public affairs events on NASA
Select TV.   All times are Eastern.



Thursday, December 14.....

     10:00 A.M.    Coverage of the NASA B-52/Pegasus air launch
                   booster captive flight.


       3:00 P.M.   NASA Update will be transmitted.


Tuesday, December 19.....


Note: a pre-launch news briefing schedule will be filed tomorrow.
NASA Select TV will provide near full time coverage of the STS-32
space shuttle mission from lift off through landing.

All events and times are subject to change without notice.

-----------------------------------------------------------------
These reports are filed daily, Monday through Friday, at 12 noon,
Eastern time.
-----------------------------------------------------------------
A service of the Internal Communications Branch (LPC), NASA
Headquarters, Washington, D.C.

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

Date: 12 Dec 89 17:42:23 GMT
From: eru!luth!sunic!mcsun!ukc!axion![e-mail]  (swaraj jeyasingh)
Subject: Re: Motives

From article <[e-mail]>, by [e-mail] (Nick Szabo):
>
> So is this bad news for space fans?  Not if we can change our point
> of view, and learn to live in the 1990's instead of the 1960's.  The
> days of ten-billion dollar space projects are over.  The most productive
> economy on our planet, Japan, engages in no such projects, and has no
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> intention to start.
  ^^^^^^^^^^^^^^^^^^^

   [stuff deleted]


Bit of a sweeping statement isn`t it ? After all Japan is contributing
one of the modules for Freedom. Not to mention their HOPE orbiter project
or their recent invitation to Western firms to join in their SST engine
project. They are also devloping their own cryogenic engine, H II.

A pity there are no Japanese contributors to the net. ( a Henrichi Spenizuka
maybe ?!)
Perhaps they are all too
busy actually making things happen rather than discuss it on the net!
I for one would like to know what makes them tick. I am sure it is to do
with their culture and attitude to society rather than any "management
style or organisation theory". Sure they have their fair share of set backs
like everybody else but generally they SEEM to more purposeful and
determined in their space efforts. They don`t seem to be plagued by so many
self-doubts and questioning and politcal/industrial rivallry or
short-sightedness.   or maybe its that grass is greener etc... I have
just read that the HOTOL programme, UK`s effort to the SSTO dream, is now
effectively dead. British Aerospace, who had been funding it so far are
cutting back staff working on the project from 100 to 10. Sigh...

Sorry if this seems more relevant to soc.culture.japanese but I noticed
that quite a few of the postings to this group are of a more "philosophical"
nature rather than strictly technical. And long may it continue.



Swaraj Jeyasingh
British Telecom Research labs               [e-mail])
IPSWICH
United Kingdom

Disclaimer: No I`m not Japanese; neither am I employed by MITI !

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

Date: 13 Dec 89 19:04:43 GMT
From: mailrus!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: proposed "space-mail" incentive

In article <[e-mail]> [e-mail] (Steve Emmerson) writes:
>>On the whole, I tend to agree:  the "space mail" approach is a better
>>scheme...
>
>I'm curious about this analogy and wish to explore it further.  Does
>anyone know of a currently desirable service (or services) that is
>analogous to the early demand for more rapid mail delivery?

There actually wasn't *that* much demand for more rapid mail delivery in
the early days of air mail.  Oh, some, yes, but it could never have been
justified in a cost-benefit study, as I understand the situation.  Large-
scale demand and use came after the service was in place and people felt
they could rely on it.  This is, unfortunately, much the same situation
we now face when it comes to cheap launch services:  there is good reason
to speculate that new users would develop, but existing usage doesn't
seem sufficient, in itself, to justify major efforts.  A leap of faith
or a willingness to take some risk is needed.
--
1755 EST, Dec 14, 1972:  human |     Henry Spencer at U of Toronto Zoology
exploration of space terminates| uunet!attcan!utzoo!henry [e-mail]

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

Date: 12 Dec 89 19:46:39 GMT
From: attcan!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Mars rovers

In article <[e-mail]> [e-mail] (Paul L Schauble) writes:
>... Both the Earth
>and Mars rotate. It seems to me that in order to keep a rover operating
>you need a network of communications satellites around both planets to
>get constant communication. You also need a network of satellites in
>solar orbit to keep things operating when Mars is on the other side of
>the sun. Has anyone seriously evalused what is needed?
>
>How did Viking do this? Or did they just figure that the mission was short
>enough that they can ignore the conjunction problems and just ignore the
>loses to planetary rotation? Henry?

Conjunction problems tend to be resolved by simply planning a short period
of dormancy around then.  This isn't a big deal, as the period of serious
communications loss is not that long.  (It's annoying for missions that
want continuous data return, though.  One of the "holes" in the initial
Magellan Venus map will be due to conjunction; there is hope that it can
be filled in later.)

There is no requirement for a satellite network around Earth, as the Deep
Space Network already has three major Earth stations (Goldstone, Madrid,
and Australia) specifically to provide continuous coverage when needed.
There *is* a problem with the DSN having other commitments, but anything
short of a Mars-rover-dedicated satellite network would have the same
problem.

Having the rover on the opposite side of Mars half the time *is* a headache.
It is somewhat reduced if the rover is dormant at night, given that Earth
generally more or less faces Mars's day side and hence a good fraction of
the total other-side time is during the night, but that's not a complete
solution.  There has been talk about Mars-orbit communications satellites
in support of rover missions; a manned Mars mission would almost certainly
include comsats.  I think the current "main line" rover planning assumes
that the rover is simply out of touch half the time, though.

Viking was mostly a "sit and look" mission, with preprogrammed instructions
to record measurements and images during times when the lander was out of
touch with Earth.  The active parts -- digging with the soil scoop etc. --
were simply limited to favorable times.
--
1755 EST, Dec 14, 1972:  human |     Henry Spencer at U of Toronto Zoology
exploration of space terminates| uunet!attcan!utzoo!henry [e-mail]

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

Date: 13 Dec 89 14:09:08 GMT
From: tank!cps3xx!netnews.upenn.edu!grip.cis.upenn.edu![e-mail]  (Nathan Ulrich)
Subject: Re: Non-autonomous Mars Rover

In article <[e-mail]> [e-mail] (Steve Masticola) writes:
>
>Can a fine-grain ranging system (optical or sonic) be used to get a
>reasonably good 3D image of the Rover's immediate environment? If so,
>why not use that data to set up a delayed-real-time telepresence
>environment for an operator on Earth? If it works, the Rover could
>move at a good clip for short distances without the need for local
>autonomy.
>
>The Rover would be controlled in a "look-move-look-move" sequence.
>With Rover stopped, an operator plots and "test-drives" a course
>through a simulated environment resembling the area around the Rover.
>When he's satisfied that the course is acceptable, the instructions
>are transmitted to take the Rover through the remotely-plotted course.
>The Rover then stops and looks around some more, and possibly does
>some experiments in the place where it stopped.
>
>It would even be fairly cheap to run an experiment to study
>feasability. Anyone interested?
>
In fact, researchers in my lab are doing just this.  They are using a Puma 260
robot arm and an Iris graphics workstation with some special computational
hardware.  Essentially they create a virtual world that is shown on the
graphics screen and work several minutes in the future, so that a compressed
stream of commands can be sent to arrive (with delay) just in time to react
to the real environment.  This virtual world is predictive and based on info
gathered by robot sensors.  The model is dynamic, in that you feel the forces
necessary to accelerate objects, collisions, etc.

Obviously, there will be situations where unpredictable events occur.  The
remote robot is planned to have a certain degree of autonomy to be able to
react and protect itself, but when it runs into problems, it can just stop
and wait for the operator to tell it what to do---hopefully this would be
an exceptional situation.  Of course, the virtual world is continuously
corrected with real-world sensor information.

They have some nice results (and demos) so far, but it is not a trivial
problem by any means.

Nathan Ulrich
[e-mail]

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

Date: 13 Dec 89 16:34:47 GMT
From: hplabsb![e-mail]  (David Smith)
Subject: Re: Relative distances and sizes in the Universe.

In article <[e-mail]> [e-mail] (CUP/ASG, MLO5-2/G1 6A, 223-3283  12-Dec-1989 1233) writes:
>        On page 129 - If you traveled at the speed which the APOLLO
>    spacecraft used in an average six-day round-trip journey to Earth's
>    Moon (approximately 40,000 kilometers per hour/25,000 miles per hour),
>    it would take you 850,000 years to reach Alpha Centauri.  By contrast,
>    the faster PIONEER 10 and 11 and VOYAGER 1 and 2 Jovian probes will
>    reach that distance (4.3 light years) in only eighty thousand years.

The Apollos only reached the quoted speed momentarily.  At 25,000 mph,
the time would be around 115,000 years.  Using 850,000 years transit time,
and 4.25 ly to Alpha Centauri, the average speed comes out to 3,500 mph,
which sounds about right for Apollo's average speed.

>        On page 161 - If you used a starship traveling at one-tenth the
>    speed of light (300,000 kilometers per second/186,000 miles per second)
>    to reach the farthest star in the Milky Way Galaxy, the ship would
>    take 800,000 years to reach it from the Sun.

This implies that the farthest star in the galaxy is 80,000 ly away.  That
distance is OK for the far edge of the main galactic disk, but the disk
does not contain all of the stars.  Some globular clusters in our galaxy
are over 150,000 ly away.


            David R. Smith, HP Labs
            [e-mail]
            [phone]

-------------------------------------------------------------------------
|"Meanwhile Newton became as mad as a hatter:  by 1692 he was suffering |
|from depression, paranoia, insomnia and forgetfulness, and his hands   |
|shook.  Poor Newton's scientific work was impaired but in that state   |
|he was judged fit for public office and went on to become Master of    |
|the Mint and a Member of Parliament." -- Nigel Calder                  |
-------------------------------------------------------------------------

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

Date: 13 Dec 89 20:28:56 GMT
From: cs.utexas.edu!usc!henry.jpl.nasa.gov!elroy.jpl.nasa.gov!forsight!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update 12/13/89


                        Galileo Status Report
                         December 13, 1989

     Galileo is now 10.33 million miles from Earth and a little under 31
million miles from Venus which it will pass on February 9th. Thorough
checkouts of Galileo's engineering systems continue as scientific
instruments aboard the spacecraft are turned on and will continue
through the end of the month.

     Because of the sun's heat near Venus, Galileo's large radio antenna
will be kept unfurled and shaded until just before it returns to Earth
in December next year. It will then be able to radio its Venus science
data stored in its tape recorder.

     After a long loop out to the asteroid belt, Galileo will return to
Earth again in December, 1992, and begin its final leg to Jupiter which
it will then orbit and begin a 20 month study of the planet and its
moon.

 Ron Baalke                       |    [e-mail]
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date:    Wed, 13 Dec 89 09:08 CST
From: [e-mail]
To: <[e-mail]>
Subject: ADDITION TO SUBSCRIPTION LIST

Could you please add <[e-mail]> to
your mailing list of space digest.
                 THANKS

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

End of SPACE Digest V10 #344
*******************