Mission Operations Days: 2002/243 to 2002/249
August 31, 2002 00:00:00 GMT to September 06, 2002 00:00:00 GMT
Aqua Spacecraft and MODIS Instrument Status:
| PM-1 "Aqua" is in Fine Pointing Normal Mode FM1 MODIS is in Science Mode |
||
|---|---|---|
| Component | State(s) | Comment |
| Blackbody | A Off; B On | Nominal Science Mode |
| Calibration Electronics | A Off; B On | Nominal Science Mode |
| Control Processor | A Off; B On | Nominal Science Mode |
| Nadir Door | Unlatched, Open | Nominal Science Mode |
| Space View Door | Unlatched, Open | Nominal Science Mode |
| Solar Diffuser Door | Unlatched, Closed | Nominal Science Mode |
| FDDI Formatter | A Off; B On | Nominal Science Mode |
| FDDI Port | A Off; B On | Nominal Science Mode |
| FIFO Memory | #1 & #2 Off; #3 & #4 On | Nominal Science Mode |
| Format Processor | A Off; B On | Nominal Science Mode |
| Power Supplies | #1 Off, #2 On | Nominal Science Mode |
| PV VIS FPA | A Off; B On | Nominal Science Mode |
| PV NIR FPA | A Off; B On | Nominal Science Mode |
| PV SMIR FPA | A Off; B On | Nominal Science Mode |
| PV SMIR FPA | A Off; B On | Nominal Science Mode |
| PV LWIR FPA | A Off; B On | Nominal Science Mode |
| PC LWIR FPA | A Off; B On | Nominal Science Mode |
| RC Outgas Heaters | All 3 (CS, IS, OS) Off | Nominal Science Mode |
| RC LWIR FPA Heater | Off | Nominal Science Mode |
| RC SMIR FPA Heater | On | Nominal Science Mode |
| Scan Assembly | A Off; B On | Nominal Science Mode |
| SDSM | Off | Nominal Science Mode |
| SRCA | Off | Nominal Science Mode |
| PS1 Survival Heaters | Enabled | Nominal Science Mode |
| PS2 Survival Heaters | Enabled | Nominal Science Mode |
| Timing Generator | A Off; B On | Nominal Science Mode |
| Flight Software | Rev BJ | Nominal Science Mode |
| Inhibit Ids Set | None | Nominal Science Mode |
This Week's Completed MODIS Activities:
Saturday, August 31st, 2002
2002/243 05:00:00 MCL OA26: Set Blackbody temperature to 280K
2002/243 09:00:00 MCL OA26: Set Blackbody temperature to 285K
2002/243 12:00:00 MCL OA26: Set Blackbody temperature to 290K
2002/243 16:00:00 MCL OA26: Set Blackbody temperature to 295K
2002/243 16:00:30 MCL OA26: Set Blackbody heater duty cycle to FULL
2002/243 18:00:00 MCL OA26: Set Blackbody temperature to 300K
2002/243 20:00:00 MCL OA26: Set Blackbody temperature to 315K
2002/243 23:00:00 MCL OA26: Set Blackbody temperature to 270K
2002/243 23:00:30 MCL OA26: Set Blackbody heater duty cycle to THIRD
Sunday, September 1st, 2002
2002/244 19:00:00 MCL OA26: Set Blackbody temperature to 285K
Monday, September 2nd, 2002
None
Tuesday, September 3rd, 2002
None
Wednesday, September 4th, 2002
2002/247 15:31:16 - 15:45:14 MCL OA16: SD/SDSM Screened, B-side
2002/247 17:10:08 - 17:24:06 MCL OA15: SD/SDSM Open, B-side
Thursday, September 5th, 2002
None
Friday, September 6th, 2002
None
This Week's Scheduled MODIS Activities Not Completed:
A formatter Night mode transition did not occur as planned at 16:43:53 on DOY 2002/245. There was no health & safety or operational impact to the instrument due to this missed formatter command.
Upcoming MODIS Events:
Wednesday, September 11, 2002
254/12:18:47 - 12:32:45 MCL OA16: SD/SDSM Screened, B-side
254/13:57:39 - 14:11:37 MCL OA15: SD/SDSM Open, B-side
Maneuvers:
A Drag Make-up maneuver is planned for Thursday, September 12th (2002/255) at 15:23 GMT. There will be a loss of pointing accuracy (including a yaw maneuver to +14.35 degrees) from about 14:20 to 16:20 GMT that day.
There will not be a lunar calibration roll maneuver for Aqua in September. The required roll angle would have exceeded the limit of -20 degrees.
The Deep Space Calibration pitch maneuver(s) have been indefinitely suspended pending mission review.
MODIS Anomalies:
Another MODIS stored command was "dropped" at 16:43:53 on September 2nd, 2002 (2002/245). The missed command was to set the formatter to Night rate. As a result, an extra half-orbit of day rate data were collected while the spacecraft groundtrack was over the night side of the earth. The Aqua Flight Operations Team was able to successfully dump the extra MODIS data to the ground within two EPGN contacts.
This marks the fifth dropped command event since the launch of Aqua and is the 7th MODIS command lost. The leading suspected cause of this anomaly is a timing issue between the receipt of the time synchronization data word and the receipt of the MODIS stored command.
Two Aqua flight software change requests have been submitted to correct and work-around this anomaly. The first will modify the spacecraft Bus Scheduler Task (BST) by switching the MODIS ground-command timing slots with the MODIS stored-command timing slots. This may alleviate the problem by allowing more time between the synchronization data and the stored command execution. However, the command drop risk then may transfer to commands executed in real-time ground procedures.
The second flight software change will modify two MODIS fault management Stored Command Sequences (SCSs) to include a command to disable the spacecraft "I am OK" (IMOK) signal to MODIS. This will allow MODIS to autonomously transition to Safe Mode in the event of a spacecraft anomaly instead of relying on the successful execution of stored commands. This software change should alleviate the greatest health & safety risk to the instrument due to the dropped command anomaly.
General Instrument Comments:
FM1 MODIS is in Science Mode. The SVD and NAD are Open, the survival heaters are enabled, and the Black Body is heated to 285 K.
MODIS Telemetry Trends:
The FM1 MODIS instrument telemetry is trending nominally.
Non-MODIS Significant Events:
The Aqua status can be viewed online at:
http://jupiter02.gsfc.nasa.gov/links/links.htm
Note: A password is now required to access the EOS mission links. There are directions at the above URL for how to obtain a username/password.
Limited Life Item Status:
SRCA 10W Lamp #1: 206.4 of 500 hours
SRCA 10W Lamp #2: 179.5 of 500 hours
SRCA 10W Lamp #3: 182.3 of 500 hours
SRCA 10W Lamp #4: 57.7 of 500 hours
SRCA 1W Lamp #1: 500.4 of 5000 hours
SRCA 1W Lamp #2: 269.8 of 5000 hours
Solar Diffuser Door: 1804 of 3022 Movements
Nadir Aperture Door: 1051 of 1316 Movements
Space View Door: 630 of 1316 Movements