UARS Weekly Status Report

26 May 2000




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                UARS WEEKLY STATUS REPORT - 26 MAY 2000

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

We continue to gather enough data to meet all the SOLSTICE science
objectives during this period of reduced tape recorder operations. 
SOLSTICE operates normally, collecting solar data on all available 
orbital tracking periods and stellar calibration observations whenever 
possible. Level 2 processing is halted due to bugs in the OA_SSPP_ATT
service. CDHF and CSC personnel are working on the problem.

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SUSIM
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Nothing received.

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ACRIM
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Nothing received.

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PEM
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     The PEM AXIS measured X-rays from half of its camera (8 pixels) from
May 3 to May 6 and again beginning May 20.  The full AXIS instrument measured
X-rays between May 6 and May 12.  At the present time, PEM energy deposition
is not being generated due to failures in the inversion code.  These are 
currently being examined.

     The PEM spectrometers continue to be active under PMON control*.  At the 
present time, PEM energy deposition is not being generated.  Recent data 
configuration changes have affected PEM software causing multiple failures.  
These failures are being reviewed by the PEM team.  In order to correct for new 
telemetry requirements, PEM will need to update processing code with a patch 
delivery.  Updated HEPS calibration parameters were finalized and are ready for 
delivery.  Updated MEPS quality calibration files were finalized and are ready 
for delivery.  Level 3 software errors, discovered by Dr. Dean Pesnell, have 
been fixed; his suggestions have been incorporated with in the PEM production 
code.  Both updated HEPS and MEPS calibration data, along with the Level 3 
code changes, will influence the in-situ energy deposition predictions, so new 
versions of PEM energy deposition Level 3 files will be generated.

*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 received.

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WINDII
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Nothing received.

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MPG
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Routine processing of instrument Daily Activity Plans continues with no 
problems. The MPG continues to assist the Project Scientistwith the scheduling 
of instrument operations. 

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CDHF
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The CDHF processed current day data through level 3 for all active
instruments. Additionally, CDHF personnel reprocessed: (R)= Requested
   (C) = Complete, (F)= Failed  (L) = Days remaining to reprocess.
            2 days SEN (5.0) PROD (1992)         2R-2C=0L

Data received and cataloged at the CDHF in the month of March 2000 has been
previewed for HALOE, NMC, and UKMO in preparation for the DAAC.

CDHF REHOST:
-  Successful processing on Rehost System:
Attitude Extraction, Observatory Log, Sensor Extraction, HALOE, MLS,
SUSIM, Solstice, and WINDII.
                                                                       
Preparing to test HRDI, ISAMS V12.0 and PEM V3.32 software on the
Rehost System.
                  
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FOT
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                                  REPORTING PERIOD

This report covers 13 May 2000 (Orbit 47388, GMT Day 134) through 19 May 2000 
(Orbit 47491, GMT Day 140).

                                SPACECRAFT OPERATION

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


                          INSTRUMENT OPERATIONAL CHANGES


              Instrument     Time       Orbit     Comment
              WINDII       140/0008     47477     On

The beta angle ranged between the angles of 69.3 degrees to 67.3 degrees for 
this report period.  The beta angle is now decreasing toward a minimum angle of 
+0.0 degrees on 05 June 2000 (DOY 157).

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 23.8 V end-of-night (EON) load bus voltage.  Battery 
temperatures are stable with a temperature delta between Battery 2 and Battery 
3 of 0.8 to 1.0 degrees C.  Additional battery performance data for each 
battery on 12 May 2000 and 19 May 2000 are provided in Appendix D.

The clock error ranged from -12.1 to 11.0 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  =  02
%     ALERTS         =  00 

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

%     FOT           =  05
%     SUSIM         =  04
%     HRDI          =  03
%     WINDII        =  01

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

%     FOT           =  02

Three (3) Anomaly Reports remained OPEN at the end of this report period (see 
Appendix E).

TRANSPONDER FREQUENCIES:
- Transponder A:  00/091  -  2287.496948
- Transponder B:  00/091  -  2287.499113


                                GROUND SYSTEM OPERATION

Two (2) operational support problems occurred this period.  Anomaly Reports are 
included in Appendix E.

The data loss calculations supplied by Data Capture Facility (DCF) from mission 
start through UTC Day 00/139 show the observatory data loss to be 295 hours, 38 
minutes, 10.561 seconds (an increase of 0 minutes 0.00 seconds since the last 
report period).  This is a 0.40 percent data loss which equals a 99.60 percent 
data capture for the mission.


                               OTHER SIGNIFICANT EVENTS

                               UARS SATELLITE OPERATIONS

The FOT was finally able to load the new TMONs into the simulator this week.  
Testing of these TMONs has already begun and will continue into next week.  
Once the TMONs have been thoroughly tested, they will be presented for review 
and approval before uplink.

The FOT continues to develop an online procedure for safehold should it happen 
before the new TMONs are in place or during and OBC halt.  The NASA power 
engineers were able to calculate the proper offset angle for this procedure.  
This was the last calculation to be made so the procedure can now be finalized.


                                      MEETINGS

The FOT attended the UARS FSW Meeting on 15 May 2000.  The main topic discussed 
was the three TDRS patch to increase the data coverage for UARS.  The FSW teams 
continues to analyze the GRO patch to see if it can be adapted to UARS.  They 
also plan to talk with the CMS software team to develop an implementation plan.


                             FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for June 05, 2000 (DOY 157).  This maneuver 
will be a Forward to Reverse Flight maneuver (Northern Hemisphere viewing).


Attachments:  Appendix A,   Real-time Commands 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 19 May 2000

  ORBIT    AOS       NO.      SUBSYS     REASON
  -----    ---       ---      ------     -------
  47399    134/1922  00-212   HRDI       SAFEHOLD - HI BARREL TEMP
  47418    136/0141  00-213   OBC        Clk Adj fr 41.2 to 20.6   msec/day
  47444    137/1846  00-214   OBC        Clk Adj fr 20.6 to 41.2 msec/day
  47444    137/1928  00-215   HRDI       SAFEHOLD - HI BARREL TEMP
  47462    139/0005  00-216   SUSIM      EXCEPTION CLEAR
  47466    139/0551  00-217   NBTR       PLAYBACK
  47470    139/1207  00-218   HRDI       SAFEHOLD - HI BARREL TEMP
  47472    139/1611  00-219   SUSIM      SUN ACTIVATE CMD
  47473    139/1752  00-220   SUSIM      DET OFF
  47477    140/0008  00-221   WINDII     POWER ON
  47479    140/0228  00-222   OBC        Clk Adj fr 41.2 to 20.6 msec/day
  47480    140/0412  00-223   SUSIM      SUSIM SUN ACTIVATE
  47481    140/0553  00-217   NBTR       PLAYBACK

_______________________________________________________________________________
 
                                   APPENDIX B
                       OUT-OF-LIMITS & ALERTS OCCURRENCES
                            Week ending 19 May 2000

The following Out-Of-Limits occurrences were detected:

   MNEMONIC       STATE     DESCRIPTION          ORBITS
   ---------      -----     ------------         ------
   HRPTSBARTMP    R-LO      HRDI BARREL TMP      47399,421,462-72,81-91
   HRPTSBARTMP    Y-LO      HRDI BARREL TMP      47405-08,417-20,432-39,461

The following ALERT occurrences were detected:

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



                                      APPENDIX C
                          CLOCK & SOLAR ARRAY RATE CORRECTIONS
                                Week ending 19 May 2000

                             CLOCK DRIFT RATE ADJUSTMENTS

   ORBIT     TIME                                CLOCK RATE CHANGE
   -----     ----                                -----------------
   47418     136/01:42 (15 May 00)               from 41.6 to 20.6 msec/day
   47444     137/18:51 (16 May 00)               from 20.6 to 41.6 msec/day
   47479     140/02:31 (19 May 00)               from 41.6 to 20.6 msec/day

_______________________________________________________________________________

                                      APPENDIX D
                             UARS BATTERY PERFORMANCE DATA
                                 Week ending 19 May 2000


     12 May 2000 - GMT Day 133 Beta = 69.3 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    +0.0/-22.4     -2.73/-4.31  +0.0/+0.0    15.8      0.000     0.0
2    +16.8/-11.2    +3.23/+1.97  +18.4/-14.0  27.0      1.040     15.0
3    +16.8/-22.4    +2.60/+1.34  +17.6/-13.6  27.0      1.037     14.8


     19 May 2000 - GMT Day 140 Beta = 67.3 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    +11.2/-5.6    -3.68/-4.62   +0.0/+0.0    15.8      0.000      0.0
2    +16.8/-11.2   +3.87/+2.92   +23.2/-14.4  27.5      1.070      16.5
3    +16.8/-22.4   +2.92/+1.97   +22.4/-13.6  27.5      1.068      16.0


               V/T LEVEL CHANGES
         ORB#        TIME           LVL FR-TO
         -----       ----------     ----------
                     no changes     V/T 5


                                   APPENDIX E
                              UARS ANOMALY REPORTS
                             Week ending 19 May 2000

                         NEW ANOMALY REPORTS GENERATED
  AR NO.     SUBSYS    ORBIT     TIME       TTR      PROBLEM/DATA LOSS
  ------     ------    -----     ----       ---      -----------------
  00-021     FOT       47408     135/1005   14170    GENERIC LATE ACQ
  00-021     FOT       47458     138/1707   14170    GENERIC LATE ACQ

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

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

                                 OPEN ANOMALY REPORTS
  AR NO.    SUBSYS     ORBIT     TIME       TTR      PROBLEM/DATA LOSS
  ------    ------     -----     ----       ---      -----------------
  99-064    FOT        44135     10/8-9/99  N/A      HRDI Cal Lamp Errors
  99-071    FOT        44398     299/1212   21512    TPF Not Receiv 512
  00-007    FOT        see list  May 00     14170    Generic Late Acq.

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