UARS Weekly Status Report

14 May 2004




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                UARS WEEKLY STATUS REPORT - 14 MAY 2004

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

Nothing received.

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

SUSIM was turned off for May 6-13.

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

     Level 2 PEM HEPSA data files are being reprocessed for submission to the 
DAAC.  This data has been designated as version 2; however, there is no format
difference from the version 1 data format.  Version 2 HEPSA data is being 
generated because it was discovered that there exists processing errors within
some of the HEPSA version 1 data files.  Thus, if you are using any HEPSA
version 1 data files from the DAAC, please replace them with the version 2
data files.  Currently, HEPSA data between 1991274 and 2003365 has been 
reprocessed and archived at the GSFC DAAC.  

     Level 2 PEM MEPS data file documentation is complete and submitted to 
the DAAC.  MEPS data files are version 1.  Processed MEPS data files at the 
DAAC archive are between 1991274 and 1999039. MEPS data files between
1999040 and 1999079 are waiting for DAAC collection.

     PEM continues to receive NMC data files from NOAA.  No problems have
been encountered.  NOAA has changed the binary structure of the NMC data and
PEM is now receiving two data streams, one in the original VAX format and the
other from their new binary format.

     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

*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.

***********
HALOE 
***********

Nothing received.

***********
MLS
***********

Nothing received.

***********
HRDI
***********

Nothing received.

***********
MPG
***********

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.

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

Nothing received.
                  
***********
FOT
***********

                           REPORTING PERIOD

This  report covers 01 May 2004 (Orbit 69150, GMT Day 122) through  
07 May 2004 (Orbit 69254, GMT Day 128).


                         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
       HALOE         123/2246      69179     POWER OFF
       PEM           125/2202      69208     ZEPS/NEPS OFF
       PEM           125/2202      69208     AXIS 1 & 2 OFF
       SOLSTICE      126/2238      69224     SOLSTICE TO DAY ONLY
       SUSIM         126/2238      69224     POWER OFF



A Forward-to-Reverse Yaw Around maneuver (number 129) was successfully
executed in Orbit 69249 beginning 128/14:51:39Z and completing at
128/15:28:49Z on 07 May 2004.  All instruments were in their off or
standby mode (except for SOLSTICE in day-only).  Due to the SA
position at 269 degrees, the effective night length of the spacecraft
after the maneuver was approximately 57.89 minutes.  Post maneuver
analysis of data indicate that during the Yaw Around, the end-of-night
load bus voltage was 24.96 volts and the average depths of discharge
(DODs) on Batteries 2 and 3 were approximately 21.55 and 21.32 percent
respectively.  The next (reverse-to-forward) YAW is scheduled for 06
June 2004 (DOY 158).

The beta angle ranged between the angles of 24.1 degrees to 01.2
degrees for this report period.  The beta angle is now increasing
towards a maximum angle of 36 degrees on 22 May 2004 (DOY 143).

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 1.27 to 1.29 degrees C.  Additional
battery performance data for each battery on 30 April and 07 May 2004
are provided in Appendix D.

The clock error ranged from 10.5 to -12.5 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       =    04
    HALOE     =    01
    PEM       =    02
    SOLSTICE  =    01
    SUSIM     =    01



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

    FOT  =    01

One (1) Anomaly Report remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

One (1) operational support problem 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


The FOT began taking SSA only events on TDW on 23 April 2004.  This
change to operations was needed due to the TDRS-8 move to TDW.  Since
the SSA service is in higher demand than the MA service, the FOT
receives approximately 50% of the events requested.  This effectively
yields the realtime support of 2.5 TDRS instead of 3 TDRS.  The FOT
will continue to operate in this mode until the software fix to the
CMS is made to ingest the SMA view periods correctly.  Preliminary
estimates project this fix to be released to operations no sooner than
two months from now.


                               MEETINGS


The FOT attended the UARS Monthly Status Review on 03 May 2004 to
review the significant events for March and April.

                                   
                       FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 06 June 2004 (DOY 158).  This
maneuver will be a Reverse to Forward Flight maneuver (Southern
Hemisphere viewing).


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 07 May 2004

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
69160   122/1634   04-127   OBC/CLK     CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
69179   123/2246   04-128   HALOE       POWER OFF
69181   124/0209   04-129   OBC/CLK     CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
69208   125/2202   04-130   PEM         ZEPS/NEPS OFF
69208   125/2202   04-131   PEM         AXIS 1 & 2 OFF
69224   126/2238   04-132   SOLSTICE    SOLSTICE TO DAY ONLY
69224   126/2238   04-133   SUSIM       POWER OFF
69234   127/1438   04-134   MPS         VT LEVEL 6 (YAW)
69241   128/0236   04-135   OBC/CLK     CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
69248   128/1355   04-134   OBC/TAM     YAW MANEUVER COMMANDS
69249   128/1525   04-134   OBC         YAW MANUEVER
69249   128/1550   04-134   OBC/TAM     YAW MANEUVER COMMANDS


                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                        Week ending 07 May 2004

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 07 May 2004

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
69160          122/1636               CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
69181          124/0209               CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
69241          128/0236               CLK ADJ FR 0.0 TO -20.6 MSEC/DAY



                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                        Week ending 07 May 2004


     30 April 2004 - GMT Day 121 Beta = 26.5 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    -700.0/-700.0 -3.05/-4.63  +00.0/+00.0  07.0     0.00      0.0
2     +00.0/-179.2 +5.46/+4.50  +28.4/-14.0  24.6     1.04     20.4
3     +22.4/-134.4 +4.50/+3.55  +27.6/-14.4  24.6     1.03     20.2

     07 May 2004 - GMT Day 128 Beta = 01.2 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    -700.0/-700.0 -3.05/-4.63  +00.0/+00.0  07.0     0.00      0.0
2     +00.0/-184.8 +5.79/+4.50  +27.2/-13.6  25.0     1.00     21.6
3     +22.4/-072.8 +4.50/+3.23  +26.8/-14.4  25.0     1.00     21.3


     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
69234          127/1438   LV5 -> LV6


                              APPENDIX E
                         UARS ANOMALY REPORTS
                        Week ending 07 May 2004

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
04-024    FOT       69223     126/2132  30832     Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
04-019    FOT       See List  Apr 04    30832     Generic Late Acquisition
04-021    FOT       69060     116/0050  30824     Telemetry Dropouts
04-022    FOT       69132     120/2000  35744     Negative Acquisition
04-023    FOT       69134     120/2331  35746     Data Drop Out

                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
------    ------    -----     ----      ---       -----------------
04-024    FOT       See List  May 04    30832     Generic Late Acquisition