Mission Operations Days: 2002/208 to 2002/214
July 27, 2002 00:00:00 GMT to August 02, 2002 00:00:00 GMT
At approximately 2002/207-21:19 GMT there was an anomaly identified by several Command and Data Handling (C&DH) TAXI overflow errors. Three distinct time periods of errors were reported:
207/21:19 - 207/23:00
207/23:21 - 208/01:00
208/02:32 - 208/04:00
See the MODIS Anomalies section below for more details.
Terra Spacecraft and MODIS Instrument Status:
| Terra (AM-1) is in Normal Mode MODIS is in A-side Science Mode |
||
|---|---|---|
| Component | State(s) | Comment |
| Blackbody | A On (290 K); B Off | Nominal |
| Calibration Electronics | A On; B Off | Nominal |
| Control Processor | A On; B Off | Nominal |
| Nadir Door | Unlatched, Open | Nominal |
| Space View Door | Unlatched, Open | Nominal |
| Solar Diffuser Door | Unlatched, Closed | Nominal |
| FDDI Formatter | A On; B Off | Nominal |
| FDDI Port | A On; B Off | Nominal |
| FIFO Memory | #1 & #2 On; #3 & #4 Off | Nominal |
| Format Processor | A On; B Off | Nominal |
| Power Supplies | #1 On, #2 Off | Nominal |
| PV VIS FPA | A On; B Off | Nominal |
| PV NIR FPA | A On; B Off | Nominal |
| PV SMIR FPA | A On; B Off | Nominal |
| PV LWIR FPA | A On; B Off | Nominal |
| PC LWIR FPA | A On; B Off | Nominal |
| RC Outgas Heaters | All Off (CS, IS, OS) | Nominal |
| RC LWIR FPA Heater | On (83 K) | Nominal |
| RC SMIR FPA Heater | Off | Nominal |
| Scan Assembly | A On; B Off | Nominal |
| SDSM | Off | Nominal |
| SRCA | Off | Nominal |
| PS1 Survival Heater | Enabled | Nominal |
| PS2 Survival Heater | Enabled | Nominal |
| Timing Generator | A On; B Off | Nominal |
| Flight Software | Rev BD + 7 sets of patches
|
Nominal |
| Inhibit Ids Set | None | Nominal |
| TMON 66 | Disabled | Nominal |
| TMON 67 | Disabled | Nominal |
| TMON 68 | Enabled | Nominal |
| TMON 69 | Disabled | Nominal |
This Week's Completed MODIS Activities:
Friday, July 26, 2002
Continuation of Blackbody stepped calibration:
2002/207 21:00:00 ATC MOD_OA26_BB_295K_A.1 Set blackbody temperature to 295K on the A-side
2002/207 21:00:30 ATC MOD_OA26_BB_DCYCLE_FULL.1 Set blackbody duty cycle to FULL (100%)
2002/207 23:00:00 ATC MOD_OA26_BB_300K_A.1 Set blackbody temperature to 300K on the A-side
Saturday, July 27, 2002
2002/208 01:00:00 ATC MOD_OA26_BB_315K_A.1 Set blackbody temperature to 315K on the A-side
2002/208 04:00:00 ATC MOD_OA26_BB_270K_A.1 Set blackbody temperature to 270K on the A-side
2002/208 04:00:30 ATC MOD_OA26_BB_DCYCLE_THIRD.1 Set blackbody duty cycle to THIRD (33%)
Sunday, July 28, 2002
2002/209 00:00:00 ATC MOD_OA26_BB_290K_A.1 Set blackbody temperature to 290K on the A-side
Monday, July 29, 2002
Lunar Roll Maneuver (-7.7312 degree roll)
2002/210 04:52:55 ATC MOD_OA04_NIGHT_RATE.1 (moved ahead 00:03:23 to even out day/night rate from roll)
2002/210 05:11:25 - 05:18:11 ATC MOD_OA08_ROLL_MAN.3
2002/210 05:11:25 ATC MOD_SET_FR_RATE, TO = DAY
2002/210 05:11:27 ATC MOD_SET_FR_SCIABNORM, TO = ABNORM
2002/210 05:11:29 ATC MOD_SET_FR_PC_DCRCMP, TO = OFF
2002/210 05:11:31 ATC MOD_SET_FR_PV_DCRCMP, TO = OFF
2002/210 05:11:33 ATC MOD_SET_FR_ENC_DELTA, TO = -3072
2002/210 05:18:03 ATC MOD_SET_FR_ENC_DELTA, TO = 0
2002/210 05:18:05 ATC MOD_SET_FR_PV_DCRCMP, TO = ON
2002/210 05:18:07 ATC MOD_SET_FR_PC_DCRCMP, TO = ON
2002/210 05:18:09 ATC MOD_SET_FR_SCIABNORM, TO = NORM
2002/210 05:18:11 ATC MOD_SET_FR_RATE, TO = NIGHT
2002/210 05:49:10 ATC MOD_OA03_DAY_RATE.1 (moved later by 00:03:23 to even out day/night rate from roll)
Tuesday, July 30, 2002
None
Wednesday, July 31, 2002
2002/212 20:12:48 ATC OA-16: SD Screened, SDSM Fixed at Sun, A-side
2002/212 21:51:41 ATC OA-15: SD Open, SDSM Fixed at SD, A-side
Thursday, August 1, 2002
None
Friday, August 2, 2002
None
This Week's Scheduled MODIS Activities Not Completed:
None
Upcoming MODIS Events:
August 2002 calibrations include bi-weekly SD/SDSM calibrations, an SRCA Full Radiometric calibration, and a PV electronics calibration. A lunar calibration via roll maneuver is also planned for August 27th.
Maneuvers:
The next Terra MODIS Lunar Calibration Roll is scheduled for 2002/239 (August 27, 2002), with data collection from 21:21:53 to 21:28:23 GMT and a roll angle of -5.9785 degrees.
The sixth Terra inclination adjust maneuver has been pushed back to an unspecified date in September to facilitate Lockheed Martin development at Valley Forge for products to support long term planning of possible future inclination maneuvers.
The Terra Deep Space Calibration Maneuver is still postponed. The maneuver date is not expected until late summer of 2002.
MODIS Anomalies:
C&DH MODIS TAXI Overflow Errors
At approximately 2002/207-21:19 GMT there was an anomaly identified by several Command and Data Handling (C&DH) TAXI overflow errors. Three distinct time periods of errors were reported:
207/21:19 - 207/23:00
207/23:21 - 208/01:00
208/02:32 - 208/04:00
It appears that the errors were only being received while the MODIS blackbody duty cycle was at FULL (100%) and the blackbody temperature had stabilized at one of the temperature plateaus. At the nominal operating conditions (290K, duty cycle = THIRD) no overflow errors were being reported. EDOS reviewed the data during the time of the anomaly and reported that only MODIS engineering data packets were lost due to this anomaly.
This anomaly is still under investigation, but upcoming blackbody calibrations (performed quarterly) will be conducted without the temperature plateaus. The calibrations will be scheduled to have the blackbody cool to 270K, heat directly to 315K, cool back down to 270K, and then resume the nominal 290K temperature.
Formatter Error Events:
The current patches loaded into the MODIS Formatter, record the number of formatter error events, but not the address where they occurred. The error rate is approaching 37 million errors per day.
Intermittent bad frame count formatter event messages (xx1B) are being observed. This is one of the event messages being used to warn of potential impacts to the science data. The MODIS halt memory transfer command is being sent after each 1B-event message. This command triggers both a CP and FR event message and thus "clears" the current MOD_SS_FR_LAST_EVENT message of the xx1B value.
The most recent error tracking spreadsheets can be retrieved from:
ftp://ftp.mcst.ssai.biz/pub/permanent/IOT/am1/analysis/FR_events/
An MS Excel spreadsheet called, AM1_FR_error_rollovers_current.xls contains the data for the times each error count "roll over" occurs.
General Instrument Comments:
MODIS is in A-side Science Mode with the blackbody maintained at 290K.
MODIS Telemetry Trends:
All systems appear to be functioning properly. Tracking of the Formatter Error Rate is continuing.
Non-MODIS Significant Events:
Science Data Loss Reports can be viewed at:
http://jupiter02.gsfc.nasa.gov:591/ssrloss/
Select "Search Data Losses" and choose Data Type: MOD
Then press the big SUBMIT button.
Limited Life Item Status:
SRCA 10W Lamp #1: 200.8 of 500 hours
SRCA 10W Lamp #2: 152.6 of 500 hours
SRCA 10W Lamp #3: 161.8 of 500 hours
SRCA 10W Lamp #4: 61.5 of 500 hours
SRCA 1W Lamp #1: 559.8 of 4000 hours
SRCA 1W Lamp #2: 276.3 of 4000 hours
Solar Diffuser Door: 1889 of 3022 Movements
Nadir Aperture Door: 536 of 1316 Movements
Space View Door: 439 of 1316 Movements