UARS Weekly Status Report

30 September 2005




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                UARS WEEKLY STATUS REPORT - 30 SEP 2005

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***********
SOLSTICE
***********

Nothing received.

***********
SUSIM
***********

Nothing received.

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PEM
***********

     HEPSA data files are version 2.  Currently, HEPSA data between 1991274 
and 2004273 has been reprocessed and archived at the GSFC DAAC.  HEPSA data 
between 2004274 and 2005099 has been processed and is waiting for archival
at the DAAC.

     MEPS data files are version 1.  Processed MEPS data files at the DAAC 
archive are between 1991274 and 2004259.  MEPS data between 2004260 and
2005099 has been processed and is waiting for DAAC archival.  

     HEPSB data files are version 1.  HEPSB data files between 1991274 and
1991366 have been processed and are waiting for DAAC archival.

     Processing of all PEM DAAC data files has been suspended until the
DAAC catches up with archiving all processed data files.  It was discovered
that DAAC changed the access IP node.  This caused failure accessing SwRI
to retrieve Level 2 data.  A change order at SwRI has been initiated.

     Tests of the AXIS1 data file formats have been successful.  The AXIS1
format design has been coded.  A test file has been generated.  A check 
program with processing scripts have also been generated.  Example binary 
read program is complete and verified.  These results have been sent to
the project.  Creation of the AXIS1 data documents for DAAC data will
begin shortly.

     PEM continues to receive NMC data files from NOAA.  No problems have 
been encountered since updates have occurred.

     The PEM data from the GUVI conjunction periods may be found at 
http://wwwpem.space.swri.edu/guvi-pem.html.  The additional electron data for 
the October and November storms of 2003 has been moved and is now located at 
http://climatology.space.swri.edu/uars_fromRudy.html.  For those users of 
SDDAS, update your UARS Meta data and these data times will appear
with full functionality.  Proton data from these storms are now located at
http://climatology.space.swri.edu/UARS_images_from_Rudy_(Apr._2004).html

     Requests have been received for storm spectral data.  Overview plots were 
produced and these plots may be found on the web at
http://climatology.space.swri.edu/UARS_images_postedJune2004.html
for the storms of October 29 of 1991, November 8-9 of 1991, April 6-7 of 2000, 
March 31 - April 1 of 2001, April 11-12 of 2001, November 6-7 of 2001, and 
November 11-12 of 2001.

     PEM has received a request for data from the super storm of November
2004.  The Dst value showed sudden commencement early on November 7, 2004
reaching a Dst value of about -380 gamma early on November 8, 2004.
PEM was not active at that time and became active late on November 8, 2004
in day only mode.  A second peak of about -280 gamma was observed on November 
11, 2004.  PEM became active in day-light only mode late on November 8.  PEM
survey spectrograms for November 8-18 of 2004 may be found at:
http://climatology.space.swri.edu/UARS_images_fromRudy.html


*Beginning of power orbit day (PEM activation): array current >5 amps, array 
     voltage >53.5 volts, and battery current >2.0 amps.  
 End of power orbit day (PEM deactivation): time in power orbit day >4 minutes,
     array current <9 amps, and battery currents <0.2 amps.
 Power orbit day variation: ~39-40 min at yaw to ~50-51 min at maximum beta.

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HALOE 
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Nothing received.

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MLS
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Nothing received.

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HRDI
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Nothing recieved.

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MPG
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The MPG is participating in the on-going UARS end of mission
planning activities.

The MPG continues to serve as the point-of-contact for UARS
instrument operations in support of the Science Traceability
Mission of UARS.

Daily processing of instrument Daily Activity Plans continues
with no problems.

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CDHF
***********

Nothing received.
                  
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FOT
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                           REPORTING PERIOD

This  report  covers  17 September 2005 (Orbit  76716,  GMT  Day  260)
through 23 September 2005 (Orbit 76836, GMT Day 266).

                         SPACECRAFT OPERATION

The observatory is now in Reverse Flight (Northern Hemisphere viewing)
and   is  performing  nominally  under  two-battery  operations.   The
instrument operational changes were:

                    INSTRUMENT OPERATIONAL CHANGES

       Instrument    Time          Orbit     Comment
       -NONE THIS REPORT PERIOD


A Forward-to-Reverse Yaw Around maneuver (number 143) was successfully
executed in Orbit 76740 beginning 260/ 14:47:03Z and completing at
260/ 15:24:13Z on 17 September 2005.  All instruments were in their
off or standby mode.  Due to the SA position at 265 degrees, the
effective night length of the spacecraft after the maneuver was
approximately 59.80 minutes.  Post maneuver analysis of data indicate
that during the Yaw Around, the end-of-night load bus voltage was
24.00 volts and the average depths of discharge (DODs) on Batteries 2
and 3 were approximately 8.85 and 31.57 percent respectively.  The
next (reverse-to-forward) YAW is scheduled for 24 October 2005 (DOY
297).

The beta angle ranged between the angles of 02.1 degrees to 24.1
degrees for this report period.  The beta angle is now increasing
towards a maximum angle of 62 degrees on 6 October 2005 (DOY 279).

Spacecraft battery 1, 2, and 3 performance monitoring continues.
Battery 1 remains OFF the charge relay.  Battery 2 and Battery 3 are
currently maintaining greater than 23.6 V end-of-night (EON) load bus
voltage.  Battery temperatures are stable with a temperature delta
between Battery 2 and Battery 3 of 10.6 to 9.2 degrees C.  Additional
battery performance data for each battery on 16 September 2005 and 23
September 2005 are provided in Appendix D.

The clock error ranged from 10.5 to -10.9 msec during this report
period.  Clock rate adjustments are listed in Appendix C.

All instrument and subsystem engineers were advised on the initial
excursion of ALERTS or Out-Of-Limits conditions detected by the FOT
for this report.  A summary is listed below and the details of ALERT
and Out-Of-Limits occurrences are listed in Appendix B.

    OUT-OF-LIMITS  =    00
    ALERTS         =    00

The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).


    FOT       =    14
    HALOE     =    01


UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.

    FOT       =    03

Two (2) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

Three (3) operational support problems occurred this period.  Anomaly
Reports are included in Appendix E.

The data loss calculations are no longer being supplied by Data
Capture Facility (DCF).

                       OTHER SIGNIFICANT EVENTS

                       UARS SATELLITE OPERATIONS

This week the FOT continues to closely monitor the condition of
battery 2 and battery 3.  Battery 2 and 3 have not been sharing load
well since the cell failure on battery 2.  Battery 3 now carries
almost 90% of the power load while battery 2 provides the remaining
10%.  The orbits leading up to the yaw were of greatest concern as the
EON load bus voltage was low due to the beta angle.  NASA power branch
has been providing daily support in monitoring the UARS battery
condition.  The FOT has been authorized to disable all platform and
instrument heaters on the SSPP.  This will be done at the earliest
available opportunity.

The FOT completed the planned repeat 30-second burn on 19 September
2005.  The burn started as planned at 262/1455 and terminated 30
seconds later.  Preliminary analysis showed that the BIAS that was
selected allowed the attitude control thrusters to come on sooner and
the translation thrusters came back on with several seconds left in
the 30-second burn.  The FOT also saw the translation thrusters off-
pulse as planned.  This engineering burn performed as expected with no
surprises.

The success of the 2nd 30-second burn cleared the way for the final
planned engineering burn of 2 « minutes on 22 September 2005.  The
primary goal of this burn was to see the spacecraft achieve steady
state with all 4-translation thrusters firing.  The burn started as
planned at 265/1459 and terminated 150 seconds later.  Post-burn
analysis showed that UARS achieved steady state approximately 35 to 40
seconds into the burn.  The initial transient was almost identical to
the earlier 30-second burn that was done on 19 September 2005.  The
individual thruster duty cycles were A [59.0%]; B [50.8%]; C [89.1%];
D [89.0%].  After the initial transient, translation thrusters C and D
operated at 100% duty cycle.  The overall duty cycle for this 150-
second burn was 72%.  While this is lower than the predicted 90% that
was used to plan out the burn schedule for UARS, it will increase and
asymptotically approach 80% as the burns increase in length.

The FOT has been directed to stand down from the first planned orbit
lowering burn on 29 September 2005 by NASA headquarters.  This stand
down order, coupled with the slightly reduced duty cycle of the UARS 4-
thruster mode will mean that the FOT will not be able to keep to its
plan of de-orbiting UARS as quickly as possible due to the cell
failure on battery 2.  The earliest that the FOT will be able to
completely expend all the hydrazine onboard will be sometime in early
to mid December.


                               MEETINGS

The FOT attended a De-boost status meeting / CAM this week on 19
September 2005.  There were no concerns raised at the CAM, and the FOT
was given permission to proceed with the calibration burn on 19
September 2005.

The FOT attended the UARS End of Mission Peer Review on 21 September
2005.  One RFA came out of the review.  The RFA was to document waive
off and abort criteria for the long duration burns for both an ACS
perspective and a collision avoidance perspective.

The FOT attended another CAM on 21 September 2005.  The FOT presented
two procs that would be used instead of manual commanding to help
reduce the time needed to setup for a burn.  The proc and contingency
commands were reviewed.  There were no concerns raised with using
procs instead of manual commanding for the 2 « minute burn on 22
September 2005.


                       FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 24 October 2005 (DOY 297).
This maneuver will be a Reverse to Forward Flight maneuver (Southern
Hemisphere viewing).

The FOT has been directed to stand down from our first scheduled 18-
minute burn by NASA HQ.  The burn was scheduled for 29 September 2005,
and has been canceled.  UARS is still go for executing the scheduled
18-minute burn on 04 October 2005 and 06 October 2005.


Attachments:   Appendix A,      Real-time Command Sheets
               Appendix B,      Out-Of-Limits   &   ALERT  Occurrences
               Appendix C,      Clock &  Solar  Array  Rate  Corrections
               Appendix D,      UARS Battery Performance Data
               Appendix E,      UARS Anomaly Reports


                              APPENDIX A
                       REAL-TIME COMMAND SHEETS
                     Week ending 23 September 2005

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
76738   260/1213   05-332   MPS         VT L6 TO L7
76739   260/1353   05-333   MACS        YAW - FWD TO REV
76741   260/1632   05-334   OBC         BANK DUMPS
76755   261/1544   05-335   HALOE       RESTOWED - REV
76769   262/1315   05-336   MACS        ENG BURN - STEP 1
76770   262/1402   05-336   MACS        ENG BURN - STEP 3,5,6
76770   262/1445   05-336   MACS        ENG BURN - STEP 7-24
76773   262/1940   05-337   OBC         OPEN EPHEM THRESHOLD / LOADS
76774   262/2057   05-337   OBC         DEFAULT EPH THRESHOLD
76774   262/2158   05-338   OBC         CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
76775   262/2339   05-339   OBC         ATC NOOP
76797   264/0920   05-340   OBC         CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
76814   265/1258   05-341   PM          ENGINEERING BURN 2:30 - STEP 1
76814   265/1351   05-341   PM          ENG BURN - STEP 3,4,5
76815   265/1453   05-341   PM          ENG BURN - STEP 6-23
76816   265/1616   05-343   MPS         VT LEVEL 7 TO LEVEL 6
76816   265/1616   05-342   OBC         EPHEM REJECT CORRECTION
76818   265/2006   05-344   OBC         POST-BURN EPHEM LOAD
76819   265/2149   05-345   OBC         ATC NOOP XMTR ON
76817   265/1745   05-342   OBC         DEFAULT EPHEM TOLERANCE
76823   266/0326   05-346   MPS         VT L-6 TO VT L-7


                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                     Week ending 23 September 2005

The following Out-Of-Limits occurrences were detected:

MNEMONIC       STATE   DESCRIPTION                ORBITS
--------       -----   -----------                ------
-None this report period.


The following ALERT occurrences were detected:

MNEMONIC     DESCRIPTION                          ORBITS
--------     -----------                          ------
-None this report period.


                              APPENDIX C
                 CLOCK & SOLAR ARRAY RATE CORRECTIONS
                     Week ending 23 September 2005

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
76774          262/2202               CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
76797          264/0922               CLK ADJ FR -20.6 TO 0.0 MSEC/DAY


                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                     Week ending 23 September 2005

     16 September 2005 - GMT Day 259 Beta = 06.7 deg, SA Pos = 269 deg

     DIFF V (mV)    TEMP (C)      CURR (amp)  EON V    AVE C/D  AVE
BAT  MAX/MIN        MAX/MIN       MAX/MIN     MIN      RATIO    DOD(%)
---  -------        --------      ----------  -----    -------  ------
1    728.0/ 728.0  -2.42/ -3.68  +00.0/+00.0  04.6     0.00      0.0
2   -700.0/-700.0  +3.87/ -0.23  +21.6/-13.6  24.3     1.03      7.1
3    067.2/-033.6  +8.07/ +7.09  +49.6/-22.8  24.2     1.01     28.5





    23 September 2005 - GMT Day 266 Beta = 24.1 deg, SA Pos = 269 deg

     DIFF V (mV)    TEMP (C)      CURR (amp)  EON V    AVE C/D  AVE
BAT  MAX/MIN        MAX/MIN       MAX/MIN     MIN      RATIO    DOD(%)
---  -------        --------      ----------  -----    -------  ------
1    728.0/ 728.0  -1.79/ -3.05  +00.0/+00.0  04.6     0.00      0.0
2   -700.0/-700.0  -0.54/ -1.79  +16.8/-06.8  26.4     1.05      3.7
3    067.2/-056.0 +10.06/ +7.41  +50.4/-25.0  26.4     1.03     29.2


     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
76738          260/1213   L6 -> L7
76816          265/1616   L7 -> L6
76823          266/0326   L6 -> L7



                              APPENDIX E
                         UARS ANOMALY REPORTS
                     Week ending 23 September 2005

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
05-044    FOT       76773     262/1940  30832     Generic Late Acquisition
05-044    FOT       76774     262/2158  30832     Generic Late Acquisition
05-044    FOT       76803     264/2009  30832     Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
-None this report period.

                ANOMALY INVESTIGATION REPORTS GENERATED
AIR NO.   SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
-None this report period.

                         OPEN ANOMALY REPORTS
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
05-042    MPS       76339     233/2347  N/A       BATTERY 2 DIFFV -700mV
05-044    FOT       See List  Sept 05   30832     Generic Late Acquisition