UARS Weekly Status Report

09 May 2003




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                UARS WEEKLY STATUS REPORT - 09 MAY 2003

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

Nothing received.

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

Nothing received.

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ACRIM
***********

Nothing received.

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

     The PEM web site has moved.  It has a new URL.  Access the PEM web site
using http://wwwpem.space.swri.edu.  The PEM data from the GUVI conjunction
periods has moved to http://wwwpem.space.swri.edu/guvi-pem.html.

     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 2001365 has been 
reprocessed and archived at the GSFC DAAC.  SwRI is working on reprocessing
data PEM for 2002.

     PEM continues to work with the GUVI team on the diagnosis of data from
the first conjunction period.  Analysis of the two conjunction passes showed
that the aurora as detected by GUVI was at higher latitude than UARS.  
GUVI images from other times from the first conjunction period show spatial
regions that both GUVI and PEM sampled when aurora was present.  Separation
is several minutes to 10's of minutes when both instruments saw aurora. 
PEM has seen no aurora during the second conjunction period.  Due to a 
spacecraft anomaly, no PEM data was collected during the third conjunction 
period.

     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.

*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
***********

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 26 April 2003 (Orbit 63571, GMT Day 116) through 02
May 2003 (Orbit 62675, GMT Day 122).


                         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
       HRDI          119/0113      63616     FULLTIME OPERATIONS
       PEM           122/2321      63675     POWER OFF AXIS 1


The  beta  angle  ranged between the angles of 70.3  degrees  to  55.8
degrees  for  this  report period.  The beta angle is  now  decreasing
towards a minimum angle of 0 degrees on 16 May 2003 (DOY 136).

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 0.63 to 0.95 degrees C.  Additional
battery performance data for each battery on 25 April and 02 May  2003
are provided in Appendix D.

The  clock  error  ranged from -11.3 to 7.0 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  =    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       =    02
    PEM       =    01
    HRDI      =    01


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

    FOT  =    04

Four (4) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

Four  (4) 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


The new switch was installed on 29 April 2003 and ran without incident
all week.  This hardware fix has hopefully resolved the network issues
seen earlier this month.

The preliminary build, which contained the fixes for the wait
statement and status buffer display issues, was installed and tested
on 30 April 2003.  Testing showed that the wait statement logic worked
properly for several operational procedures, but not with a test
procedure which waited for a rapidly incrementing counter to reach a
value.  The status buffer still had several issues including, wrong
time stamp, trickle LRVS and status buffer dumps not updating the
display properly and old messages not being cleared properly.  The FOT
has written up their test result and sent them to the Raytheon
development team for analysis.

                               MEETINGS


The  FOT attended the weekly UARS DRB on 29 April 2003, to review  the
open  DRs  and  discuss  the  details of  the  next  Eclipse  software
delivery.


                       FUTURE SIGNIFICANT EVENTS

The  next UARS Yaw slew is scheduled for 16 May 2003 (DOY 136).   This
maneuver  will  be  a  Forward to Reverse  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 02 May 2003


ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
63591   117/0841   03-101   OBC/CLK     CLK ADJ FR 41.2 TO 20.6  MSEC/DAY
63616   119/0113   03-102   HRDI        FULLTIME OPS
63662   122/0246   03-103   OBC/CLK     CLK ADJ FR 20.6 TO 0.0  MSEC/DAY
63675   122/2321   03-104   PEM         POWER OFF AXIS 1



                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                        Week ending 02 May 2003

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 02 May 2003

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
63591          117/0846               CLK ADJ FR 41.2 TO 20.6 MSEC/DAY
63662          122/0248               CLK ADJ FR 20.6 TO 0.0 MSEC/DAY

                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                        Week ending 02 May 2003

     25 April 2003 - GMT Day 115 Beta = 69.8 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  -207.2/-229.6  -3.05/-3.99  +00.0/+00.0  08.3     0.000     0.0
2   +05.6/-22.4   +3.23/+1.97  +16.8/-15.2  26.4     1.060    16.3
3   +16.8/-22.4   +2.60/+1.34  +16.8/-15.2  26.4     1.050    16.1


     02 May 2003 - GMT Day 122 Beta = 55.8 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  -235.2/-263.2  -3.68/-4.94  +00.0/+00.0  08.3     0.000     0.0
2   +05.6/-67.2   +3.87/+2.92  +23.2/-15.2  25.8     1.030    18.8
3   +16.8/-44.8   +2.92/+1.97  +22.4/-14.4  25.6     1.020    18.4

     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
-None this report period.

                              APPENDIX E
                         UARS ANOMALY REPORTS
                        Week ending 02 May 2003

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
03-011    FOT       63576     116/0945  30832     Generic Late Acquisition
03-011    FOT       63622     119/0941  30832     Generic Late Acquisition
03-017    FOT       63647     121/0145  32718     Multiple Data Dropouts
03-018    FOT       63648     121/0329  30832     Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
03-011    FOT       See List  April 03  30832     Generic Late Acquisition
03-016    FOT       63505     111/1550  NA        Server 1 Tape Drive Install
03-017    FOT       63647     121/0145  32718     Multiple Data Dropouts
03-018    FOT       See List  May 03    30832     Generic Late Acquisition

                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
------    ------    -----     ----      ---       -----------------
03-011    FOT       See List  April 03  30832     Generic Late Acquisition
03-017    FOT       63647     121/0145  32718     Multiple Data Dropouts
03-018    FOT       See List  May 03    30832     Generic Late Acquisition