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Subject: SPACE Digest V12 #676

SPACE Digest                                     Volume 12 : Issue 676

Today's Topics:
       BBXRT Status for 12/09/90 [1430 CST] (Forwarded)
           Re: space news from Oct 6 AW&ST
          [l/m 7/5] Reminders for Old Farts
             Galileo Update #2 - 12/07/90
            Re: Galileo Update - 12/11/90

Administrivia:

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

Date: 9 Dec 90 23:54:19 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: BBXRT Status for 12/09/90 [1430 CST] (Forwarded)


         BBXRT Status Report 8
         2:30 p.m. CST Dec. 9, 1990
         Spacelab Mission Operations Control
         Marshall Space Flight Center
         Huntsville, AL


         A pleasant surprise discovered last night by the BBXRT team is that
         the instrument is more immune to scatter solar light than previously
         thought.

         "What is really exciting is we didn't think we could look that close
         to the Sun and now that we can we're really picking up all the high
         priority targets," said Principal Investigator Dr. Peter Serlemitsos
         of Goddard Space Flight Center.

         For example, at about 7 a.m. CST this morning, BBXRT obtained CEN-X3,
         a famous pulsar in the Virgo galaxy.  "We really wanted to observe it,
         but thought because it was too close to the Sun we couldn't, "
         Serlemitsos said.  "But we just did."

         BBXRT was developed at GSFC in Greenbelt, MD.  Personnel in the
         Payload Operations Control Center at GSFC monitor the BBXRT operations
         and analyze data transmitted from the telescope to the ground.

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

Date: 9 Dec 90 04:41:10 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: space news from Oct 6 AW&ST

In article <[e-mail]> [e-mail] (Doug Price) writes:
>
>I do not dispute that a lot of good science can be done for a lot cheaper
>for a few more years using robots.  This zero-sum, "zap his budget so I can
>get my budget" stuff has got to go.

The planetary explorers got a good lesson in this from the tin-can folks
when our exploration funding was nearly destroyed by the Shuttle in the
early 80's.  I'm glad to see the discoverers are finally fighting
back.  What goes around comes around, astronaut fans.  We are entering
a new era where the funding proportions for "manned" stunts and real
exploration and industry will be reversed, leading to a new Space Age,
with an immense gain in knowledge of the solar system's every corner, and
the blossoming of space industry.  I eagerly await the death of Fred,
Colombus, Hermes, and the other punch-card era throwbacks so that we can
move forward more quickly into this new age of knowledge and commerce.


--
Nick Szabo            [e-mail]
"We live and we learn, or we don't live long" -- Robert A. Heinlein
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: 9 Dec 90 11:59:55 GMT
From: data.nas.nasa.gov!amelia![e-mail]  (Eugene N. Miya)
Subject: [l/m 7/5] Reminders for Old Farts

Hints for old users (subtle reminders) You'll know these.

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please keep lines under 80 characters for those using ASCII terms (use <CR>).

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

Date: 11 Dec 90 04:40:56 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update #2 - 12/07/90


                          GALILEO STATUS REPORT
                             December 7, 1990

     As of noon (PST) Thursday, December 6, 1990, the Galileo spacecraft is
1,066,990 miles from the Earth and traveling at a heliocentric speed of
66,485 miles per hour; distance to the Sun is 92,611,910 miles (0.99 AU).
Round trip light time is 0 minute, 14 seconds.

     A NO-OP command was sent on November 30 to reset the Command Loss Timer
to 96 hours.  The Command Loss Timer was subsequently reset from 96 hours to
72 hours on December 3.  NO-OP commands to reset the timer were sent, as
planned, on December 3, 4, and 5.

     A star vector update was successfully performed on November 30.  This
updated star information will be used for the forthcoming sequence activities.

     Commands were sent on December 1 to reduce the telemetry downlink data
rate from 115.2 kbps to 7.68 kbps.  The lower data rate was selected to
guarantee high quality data return consistent with RF link performance.  On
December 3, commands were sent to restore the downlink telemetry rate to 115.2
kbps consistent with link performance and the on-board sequence expected data
rate.

     The Relay Radio Hardware (RRH) oscillators were successfully powered on
November 30 in preparation for the Probe checkout on December 4.  Several
engineering electrical heaters were configured on November 30 and December 4
to assure adequate power margin to support the Probe checkout.

     The Probe checkout was successfully performed on December 4.  All power
consumption and thermal profiles were near predicted levels. Preliminary
analysis indicates probe operation was normal and no unexpected probe events
were observed; an initial assessment concludes the Probe health is excellent.
A brief real-time data outage, due to a ground communication intermittent
problem, occurred just prior to the initial pump down of the Neutral Mass
Spectrometer (NMS) thereby precluding real time evaluation of Argon gas
buildup since the first flight probe checkout in October 1989.  The data lost
during the outage was subsequently retrieved from tapes and provided to the
probe personnel; analysis is in process.

     Commands were sent on December 5 to change the on-board automatic fault
protection response to select Low Gain Antenna 2 (LGA-2).  These commands
configure the fault protection to a state consistent with the planned antenna
switch from LGA-1 to LGA-2 on December 8.

     The spacecraft's downlink telemetry data rate was increased to 134.4 kbps
via the stored sequence on December 5.  This data rate is the spacecraft's
maximum designed data rate and this was the first in-flight use of this rate;
the data was successfully received and processed by the Ground Data System
(GDS).

     The VE-11 (Venus-Earth 11) Earth 1 encounter sequence memory was
successfully transmitted and received by the spacecraft in two parts, Part A
on December 5 and Part B on December 6.  The VE-11 sequence will go active on
December 7 and control spacecraft events to December 17.

     Commands were sent on December 5 to turn on the PLS (Plasma) instrument's
high voltage in preparation for data collection during the Earth 1 encounter.
Several Delayed Action Command (DACs) were also sent on December 5 for
execution on December 8.  These commands will power off the PLS instrument and
turn on its electrical replacement heater shortly prior to closest approach.
This action assures the PLS instrument remains within safe thermal limits
established by the Principal Investigator.

     The AC and DC bus imbalance measurements were relatively stable.  The AC
measurement fluctuated about 3 DN and is reading near 46 volts.  The DC
measurement varied about 3 DN and is reading about 2 volts, possibly
indicative of a return side leakage path to chassis between 80-150 ohms.  All
other power-related measurements and spacecraft telemetry are normal.

     The Project reviewed and approved the final sequence and command products
for VE-12 on December 3.  The VE-12 sequence controls spacecraft activities
from December 17 to February 18, 1991. This sequence contains 9 SITURN events,
17 Sun acquisitions, 3 RPM (Retro Propulsion Module) flushing activities,
the LGA-2 to LGA-1 antenna switch, 5 windows for the CDS (Command Data
Subsystem) memory tests, attitude control calibration events, radio science
tests, UVS (Ultraviolet Spectrometer) observations, several cruise science
memory readout activities, 4 maneuver windows for TCM-9A (Trajectory
Correcition Maneuver) on December 18, 19, 20, and 21.

     The Flight Control and Support Office (FCSO) and the Engineering Office
have completed analysis of prime and backup data sources to determine the
completeness of data received at JPL during the Probe checkout on December 4.
The FCSO reported that the small amount of data which was missing at JPL was
recovered from data recorded at the tracking stations.  The Probe Engineering
Team (PET) was able to confirm successful completion of the Probe checkout
using the data already at JPL.

     An S-Band array test with the two 34 meter antennas at Goldstone was
completed this week by the DSN (Deep Space Network).  The test was apparently
not successful in realizing signal level gains through arraying.  Final
conclusions, causes for the unsuccessful attempt, and plans for possible la ter
tests will be reported later after post test analysis is complete.  The test
was conducted to investigate the possibility of using S-Band arraying to
reduce the Project's requirements for 70 meter station support during the
Earth 2 operations in 1992.

     Data collection from last week's NIMS (Near Infrared Mapping Spectrometer)
and SSI (Solid State Imaging) photo calibration activity was unsuccessful due
to a sequence design input data error which resulted in both instruments being
pointed off the Photo Calibration Target (PCT) mounted on the science boom.
Although, the lack of this calibration data has no effect on the health and
safety of the NIMS/SSI and does not effect the Earth 1 encounter sequence, its
loss will, however, result in later than planned detailed NIMS/SSI data
reduction.  Investigation into the cause of this sequence design input error
is in process.  Preliminary analysis suggest a possible misinterpretation of
the reference point from which the clock angle is measured.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 12 Dec 90 06:04:48 GMT
From: uokmax![e-mail]  (Robert W Murphree)
Subject: Re: Galileo Update - 12/11/90

Dear Ron Baalke or someone else in the know::i:
   i
Has the high gain radio communication antenae deployed properly and is it in good good shape?  Some of us have been waiting a year to see if it has.  The mission depends on a high data rate for real time transmission of video data from 5 AUPlease send me E-mail or reply to Sci.space sci.astro.

                                      Thanks in advance.

                                      Robert W. Murphree
                                      rwmurphr.uokmax.ecn.uoknor.edu (internet)
i

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

End of SPACE Digest V12 #676
*******************