Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_6/V12_700.TXT

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Subject: SPACE Digest V12 #700

SPACE Digest                                     Volume 12 : Issue 700

Today's Topics:
                COBE tumbling?
               Re: Black Holes
           Re: space news from Nov 12 AW&ST
             Galileo Update #2 - 12/14/90
                 Re: butthead
      Re-organization of the SPACE archive on ames.arc.nasa.gov
            More Launch Cost Data
           Re: space news from Nov 19 AW&ST
              Galileo Update - 12/14/90

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: 14 Dec 90 22:05:20 GMT
From: isis!scicom![e-mail]  (Bruce Watson)
Subject: COBE tumbling?


I have observed Cosmic Background Explorer twice
this month in the early evening twilight.
As it has moved from my zenith to the pole star the satellite
varied in brightness from 0 mag to invisibility (+6) with a
period of about 30 seconds.  Has the mission concluded and
the satellite uncontrolled or is sunlight hitting a flat
panel and reflecting specularly?

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

Date: 15 Dec 90 08:09:48 GMT
From: quasi-eli!cs.yale.edu![e-mail]  (Norman Yarvin)
Subject: Re: Black Holes

[e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Norman Yarvin) writes:
>>if one can propel some piece of matter any distance away from the black
>>hole, then one can lift fuel up to that distance; using this fuel one can
>>lift the next piece of matter even farther away from the center; and thus by
>>degrees something could escape entirely from the black hole.
>
>Not if we're talking about rockets.  That then is precisely equivalent to
>saying that by expending enough fuel, you can exceed the speed of light.
>Sure you can lift ever farther... but your increments get smaller and smaller,
>so you approach but never reach escape velocity.

This does not address the question of why something escaping from a black
hole needs to ever attain the escape velocity at low altitudes.  Certainly
rockets that escape from Earth need not.  But asking whether that scheme
would work was not my intention.  I knew it wouldn't work (nobody sane
seriously challenges physics); I was just pointing out (and asking for
confirmation of) how impossible it is to explain this phenomenon using
Newtonian concepts.  I seem to have gotten this confirmation.

This is only of interest to me because so many people in the popular
literature try to explain black holes using semi-Newtonian concepts; now I
can skip all those accounts because they will inevitably be fatally flawed.
Maybe one day I'll even get around to reading a textbook and understanding
something.

--
Norman Yarvin                    [e-mail]
 "Obviously crime pays, or there'd be no crime." -- G. Gordon Liddy

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

Date: 15 Dec 90 23:47:18 GMT
From: wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: space news from Nov 12 AW&ST

In article <[e-mail]> [e-mail] (Greg Cronau/10000) writes:
>While John Young still has the official title of "Astronaut", I believe he has
>removed himself from the active flight rotation schedule. I have not heard
>why he made this decision.

I'd guess that he has little or no chance of flying again.  He lost his
position as chief astronaut after some injudicious remarks in print about
lack of astronaut involvement in decision making.  Who gets to fly is a
matter of office politics first and technical qualifications second.

(The reason why his remarks were injudicious, by the way, is that the lack
of astronaut involvement was considered mostly his fault.  Astronauts have
busy schedules, and anything that the boss doesn't consider important tends
to fall off the bottom of the list.  Young's predecessor insisted on, and
got, astronaut involvement; Young didn't.)
--
"The average pointer, statistically,    |Henry Spencer at U of Toronto Zoology
points somewhere in X." -Hugh Redelmeier| [e-mail]   utzoo!henry

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

Date: 14 Dec 90 19:26:49 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update #2 - 12/14/90


                       GALILEO STATUS REPORT
                         December 14, 1990

     Yesterday, Galileo spacecraft successfully completed a UVS (Ultraviolet
Spectrometer) Lyman Alpha sky map.  In addition to the UVS sky map, the NIMS
(Near Infrared Mapping Spectrometer) and PPR (Photopolarimter Radiometer)
instruments were powered off as planned and a No-Op command was sent to reset
the Command Loss Timer to 3 days,

     Part I of the VE-12 (Venus-Earth 12) sequence memory uplink load was
initiated today at 9:00 A.M. PST.  The uplink will take just over 2 hours to
complete.  Part II of the VE-12 sequence will be uplinked on December 27.

     Later today, Galileo will contunue taking images of Australia as part of
its planned Earth departure movie.  Some science activity will continue on
Saturday, December 15 including final images of the Australian continent.
Earth encounter sequence activities will end on Saturday.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 14 Dec 90 19:53:41 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!olivea!olivej![e-mail]  (David Patterson)
Subject: Re: butthead

In article
<[e-mail]>, butthead@butthead (butthead) writes:
                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Aren't you one of those guys with the huge, pulsating head?
You live on Talos IV, right?

:-)

(i knew i was right)
-dave

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

Date: 14 Dec 90 20:11:13 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Re-organization of the SPACE archive on ames.arc.nasa.gov

The SPACE archive on ames.arc.nasa.gov is experiencing growing pains.  As
a result, I have partioned the archive into separate directories, according
to subject.  This should make searching more bearable as well as quicker.
The index will be updated to reflect the new layout.  This should not be
a major problem for FTP users, but it make take some changes to the mail
archive-server, which I'm working on.

In other news, I've just completed the conversion of the 39 images from the
Voyager Saturn CD-ROM.  Greg Roberts supplied the images in IMQ format, and
I used several machines to convert them into GIFs.  The images are named
c*.gif.  All are 800 x 800, 8 bits of greyscale.

For those of you not familiar with the SPACE archive, I maintain a collection
of material from NASA's Public Affairs Office and other sources.  Primarily
you will find things like Press Releases, Shuttle Status Reports, as well as,
reports on many of the active planetary probes (courtesy of Ron Baalke at
JPL).  There is also a growing collection of space-related GIFs, plus many
other miscellaneous items.  The archive may be accessed in two ways.  For
Internet users, FTP to ames.arc.nasa.gov.  Chdir to /pub/SPACE and check
for the INDEX file and new sub-directories.  For users who do not have Internet
or FTP access, the archives may be accessed by sending mail to the archive
server on ames.  Address your letters to ames!archive-server or
[e-mail].  In the subject or in the body of your
letter (but don't repeat your request in both parts!) put in commands like:

    help

    send index

    send space index

I'll work out details on how the newly segregated subdirectories are accessed
via archive-server and post the results in a later message.

If you have any problems with archive server on ames.arc.nasa.gov, please
drop me a line.  I'll do my best to rectify any problems.

                            -Peter Yee
                            [e-mail]
                            ames!yee

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

Date: 14 Dec 90 04:53:05 GMT
From: julius.cs.uiuc.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (Wales Larrison)
Subject: More Launch Cost Data


   It was recently announced that McDonnell Douglas Space Systems
Co. (MDSSC) has won a $140.6 million contract with NASA to provide
Delta II launch services for upcoming NASA science missions (Source:
NASA news release).  The basic contract is for the launch of 3
scientific satellites, and may be extended to include an additional
12 more, if desired by the government.  This contract is for launch
services and will be performed by MDSSC launch crews at KSC and
VAFB.  The missions are for the Global Geospace Science mission,
which are part of the multinational International Solar Terrestrial
Physics program.  Plans are for a July 1992 launch of Japan's
Geotail satellite, a Dec 1992 U.S. Wind satellite, and a June 1993
launch of the U.S. Polar satellite in June 1993.

   Editorial Comment:  This gives us a basis for a cost per pound
for the Delta II launch vehicle.  Rated performance of a Delta II is
about 11,110 lbs into a 100 nmi 28.5 deg circular orbit (Source:
MDSSC, "Delta II Fact Sheet").  For a commercial lot buy of 3 Delta
IIs, this is about $46.9M/launch or about $4218/lb.  To Space
Station orbit of about 250 nmi, the Delta II payload reduces to
about 10,500 lbs, for about $4461/lb. To a typical shuttle orbit of
150 nmi, the Delta II throws about 10,900 lbs, for $4302/lb.

   Commentary on the ELV market: This was rated as a "must-win" by
MDSSC.  MDSSC must maintain a production line capability of at least
8 Delta launch vehicles a year to keep their costs down to remain
competitive.  They have booked up to 12 launches a year for the next
2 years, but they have very few solid bookings beyond 3 years.
Since typical lead times for a launch vehicle are about 24 months,
they are really starting to look around for business.
   MDSSC's current mainstay contract is to launch the GPS Block II
navigation satellites, and this buy of 18 launches will run out in
about 2 more years.  The GPS Block III satellites will be larger and
of a different configuration, and their launches will be competed
between Titan, Atlas and Delta.  Another prime target for the Delta
program is the Iridium communications system contract from Motorola
(However, Motorola has yet to receive approval to use any radio
frequencies for this system, and this may be sticky since they need
a global frequency allocation to serve their planned global market,
rather than just a U.S. radio frequency allocation.)
   Titan has an existing contract for up to 75 USAF Titan-4
launches, but commercial Titan (Titan 3) has booked very few
commercial sales and is looking to go out of business if they don't
get more customers.
   Atlas has about 28 booked customers (about 18 from the US
government), and is proving to be a tough competitor for world-wide
launchers.  They've recently landed a couple of European national
scientific payloads that Arianespace thought were locked for Ariane.
   Ariane typically does not launch U.S. government payloads
(there's a "Buy American" act on launch services...), and has
recently been making loud noises about being excluded from the
largest world-wide market (US government launches), but I don't
think they will be able to compete for these for some years.  They
are a very tough competitor on the world market, and are known for
executing well-orchestrated and coordinated marketing efforts
including CNES, Aerospatiale, ESA, and the French government.
Despite the current scandal involving a French member of the EC
lobbying Turkey for a French satellite, Ariane will probably
continue to capture about 1/2 of the available market.
------------------------------------------------------------------
Wales Larrison                          Space Technology Investor



--
Wales Larrison
Internet: [e-mail]
Compuserve: >internet:[e-mail]
--------------------------------------------------------------------------

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

Date: 14 Dec 90 13:05:55 GMT
From: eagle![e-mail]  (Ronald E. Graham)
Subject: Re: space news from Nov 19 AW&ST

In article <[e-mail]>,
     [e-mail] (Henry Spencer) writes...

>Space station designers trying to decide whether it is more important to
>get started on the latest redesign or finish the enormously complex series
>of preliminary design reviews on the last design.  NASA favors the latter,
>on the grounds that much of it will not need to be re-done.  [Wanna bet?]

A lot depends on how much of the PDR material covers components that would
remain themselves intact (although moved around all over the place) after
a redesign.  Some components will remain more-or-less intact, such as the
photovoltaic arrays and the associated beta gimbals (unless something's
happened in the project office I haven't heard about yet).  In those cases,
you probably would want to get the PDR review done.  But I'd take my time
and have one eye on redesign issues at the same time, just in case.

RG

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

Date: 14 Dec 90 19:25:13 GMT
From: van-bc!ubc-cs!news-server.csri.toronto.edu!cs.utexas.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 12/14/90


                          GALILEO STATUS REPORT
                            December 14, 1990

     As of noon (PST) Thursday, December 13, 1990, the Galileo spacecraft is
2,328,560 miles from the Earth and traveling at a heliocentric speed of
80,060 miles per hour; distance to the Sun is 89, 661,240 miles (0.97 AU).
The spacecraft is in all-spin configuration and spinning at 2.89 rpm.  Round
trip light time is 0 minute, 22 seconds.

     The Galileo spacecraft superbly completed its Earth flyby gravity assist
on December 8.  Galileo's closest approach to Earth occurred at 12:34:34 PST
at an altitude of 597 miles; only 0.4 seconds late and 5 miles high with
respect to the target.

     In preparation for the Earth 1 encounter, several commands were sent
primarily to configure the spacecraft's attitude control and power state
consistent with Earth flyby needs.  On December 7, a NO-OP command was sent
to reset the command loss timer to 3 days.  Other commands sent that day
included disabling the system sunpoint fault protection and attitude control
sun algorithms, Delayed Action Commands (DACs) to power cycle the RTG Boom
heaters off/on and several DACs to position the scan platform for NIMS (Near
Infrared Mapping Spectrometer) thermal control and to update Earth spin movie
scan platform pointing.  Most of the DACs were executed on December 8 before
the Earth flyby; the Earth spin movie updates were executed on December 11
and 12.  About 20 minutes prior to closest approach, the PLS (Plasma)
instrument was also powered off, via DACs, to assure PLS thermal safety.

     After the Earth flyby, commands were sent to configure the attitude
control subsystem and the system fault protection back to its pre-encounter
cruise state.

     The LGA-1 (Low Gain Antenna 1) to LGA-2 antenna switch was successfully
performed from the stored sequence on December 8.  The switch occurred about
20 minutes prior to Earth closest approach.  The on-board switch command was
backed up by a real-time ground command about 1 minute after the on-board
switch.

     The 21st RPM (Retro Propulsion Module) thruster flushing activity was
successfully completed December 9.  Thruster temperature profiles were similar
to those observed on previous flushing activities.

     A SITURN to lead the sun was successfully completed on December 10.  The
turn, about 4 degrees, resulted in the spacecraft leading the sun about 2
degrees; another SITURN, about 6 degrees, was successfully performed on
December 13 and resulted in the spacecraft leading the sun by about 2.3
degrees.  For both activities the spacecraft performance was normal and without
incident.

     Subsequent to the SITURN on December 10, the sun gate fault protection
was re-enabled to provide protection from faults which could result in the
spacecraft being in a thermally unsafe off-sun attitude.  After the Earth
flyby, the resulting trajectory will bring the spacecraft to 0.9 AU of the sun
on January 11, 1991.

     An attitude control Target Motion Compensation (TMC) test was
successfully performed on December 10.  Attitude control data was collected at
various clock and cone angles to assess the effectiveness of TMC.  Analysis
of the data is in process and results will be used for the GASPRA encounter
in October 91.

     Another set of Delayed Action Commands (DACs) were sent on December 12 to
cycle the radio frequency subsystem ranging channel off/on to improve
telecommunications link performance at 115.2 kbps and 7.68 kbps.  The
commands will be executed by the spacecraft on December 14, 15, 16, and 17.

     A non-interactive command was successfully sent to the EPD (Energetic
Particle Detector) on December 7 to put the instrument in its scan mode in
preparation for Earth encounter data collection.

     Two non-interactive DACs were sent and executed on December 12 to lower
the HIC (Heavy Ion Counter) LET detector energy threshold and then return it
to its normal setting about 2 hours later.  This command action was taken in
response to the Principal Investigators request after observing higher than
expected counts in the LET detector; later these higher counts were discovered
to be a normal characteristic of the detector.

     Three non-interactive DACs were sent and executed on December 13 to the
DDS (Dust Detector) to increase its sensitivity.  Action to lower the
instruments threshold was taken in response to noise signatures observed post
Earth flyby; these commands will properly configure the DDS for interplanetary
cruise.

     A total of about 3400 photographs were successfully taken between
December 7 and December 13.  About 1850 were taken within 36 hours of closest
approach and 1500 were taken for the spin movie on December 11 and 12.  All
images were successfully returned except for 22 images of the spin movie,
namely, 10 contiguous frames in one segment (2 color filters) and 12
contiguous frames in another segment (2 color filters).  The image data loss
experienced was expected due to known DSS (Deep Space Station) view period
constraints.

     The AC and DC bus imbalance measurements remained relatively stable.  The
AC measurement remained about 2 DN and now reads 45.6 volts.  The DC
measurement varied about 30 DN from near 1 volt to 4.5 volts.  All other
power-related measurements and spacecraft telemetry are normal.

     The Project reviewed and approved the VE-14 cruise plan on December 13.
This sequence controls spacecraft activities from February 18 to April 29,
1991.

     The no major problems were reported with GDS (Ground Data Systems)
operations in support of Earth Closest Approach (ECA) support.  A better than
expected signal strength at switch from Low Gain Antenna 1 (LGA-1) to LGA-2
permitted 34 meter antenna and 26 meter antenna in Spain to continue to
acquire data for an additional 15 minutes through the end of track prior to
ECA.  Prompt and measured response by DSN (Deep Space Network), NOCC (Network
Operations Control Center) and Station personnel to an alarm at the Australia
34 meter station early in the post ECA pass permitted continued data
acquisition with no loss of data.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

End of SPACE Digest V12 #700
*******************