Mission Operations Days: 2002/208 to 2002/214
July 27, 2002 00:00:00 GMT to August 02, 2002 00:00:00 GMT
At 20:23 GMT on July 29th, 2002 (2002/210), the Aqua spacecraft autonomously entered Safe Mode. This caused the instruments to transition to Safe Mode as well. MODIS' doors (SVD and NAD) closed and all systems are powered off except the power supply, control processor, and timing generator. The instrument survival heaters are enabled.
See Non-MODIS significant events section below for details.
Aqua Spacecraft and MODIS Instrument Status:
| PM-1 "Aqua" is in Fine Pointing Safe Mode FM1 MODIS is in Safe Mode |
||
|---|---|---|
| Component | State(s) | Comment |
| Blackbody | A Off; B Off | Safe Mode |
| Calibration Electronics | A Off; B Off | Safe Mode |
| Control Processor | A Off; B On | Safe Mode |
| Nadir Door | Unlatched, Closed | Safe Mode |
| Space View Door | Unlatched, Closed | Safe Mode |
| Solar Diffuser Door | Unlatched, Closed | Safe Mode |
| FDDI Formatter | A Off; B Off | Safe Mode |
| FDDI Port | A Off; B Off | Safe Mode |
| FIFO Memory | #1 & #2 Off; #3 & #4 Off | Safe Mode |
| Format Processor | A Off; B Off | Safe Mode |
| Power Supplies | #1 Off, #2 On | Safe Mode |
| PV VIS FPA | A Off; B Off | Safe Mode |
| PV NIR FPA | A Off; B Off | Safe Mode |
| PV SMIR FPA | A Off; B Off | Safe Mode |
| PV SMIR FPA | A Off; B Off | Safe Mode |
| PV LWIR FPA | A Off; B Off | Safe Mode |
| PC LWIR FPA | A Off; B Off | Safe Mode |
| RC Outgas Heaters | All 3 (CS, IS, OS) Off | Safe Mode |
| RC LWIR FPA Heater | Off | Safe Mode |
| RC SMIR FPA Heater | Off | Safe Mode |
| Scan Assembly | A Off; B Off | Safe Mode |
| SDSM | Off | Safe Mode |
| SRCA | Off | Safe Mode |
| PS1 Survival Heaters | Enabled | Safe Mode |
| PS2 Survival Heaters | Enabled | Safe Mode |
| Timing Generator | A Off; B On | Safe Mode |
| Flight Software | Rev BJ | Safe Mode |
| Inhibit Ids Set | None | Safe Mode |
This Week's Completed MODIS Activities:
Saturday, July 27, 2002
None
Sunday, July 28, 2002
None
Monday, July 29, 2002
2002/210 20:23 Aqua spacecraft autonomously enters Safe Mode. All instruments sent to Safe.
Tuesday, July 30, 2002
None
Wednesday, July 31, 2002
None
Thursday, August 1, 2002
None
Friday, August 2, 2002
None
This Week's Scheduled MODIS Activities Not Completed:
None
Upcoming MODIS Events:
After recovery from Safe mode, weekly SDSM calibrations, a Blackbody calibration, and an SRCA Full Radiometric calibration will be performed.
Maneuvers:
There will not be a lunar calibration roll maneuver on Aqua in August. 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:
None.
General Instrument Comments:
FM1 MODIS is in Safe Mode. The SVD and NAD are Closed. The survival heaters are enabled and the power supply, control processor, and timing generator are powered, but all other systems are turned off.
MODIS Telemetry Trends:
General instrument temperatures have cooled and are now varying in accordance with the survival heater duty cycle. The focal planes have stabilized at approximately 240K.
Non-MODIS Significant Events:
At 20:23 GMT on July 29th, 2002 (2002/210), the Aqua spacecraft autonomously entered Safe Mode. This caused the instruments to transition to Safe Mode as well. MODIS' doors (SVD and NAD) closed and all systems are powered off except the power supply, control processor, and timing generator. The instrument survival heaters are enabled.
The anomaly was caused by a low output from one of the Earth Sensors for several seconds while the spacecraft was near the South Pole. The Earth Sensor output is computed by one of two algorithms. One algorithm is apparently flawed, and was being used at the time of the anomaly. A patch is being planned to force the sensor to choose the properly functioning algorithm for nearly all attitude possibilities.
The Aqua status can be viewed online at:
http://jupiter02.gsfc.nasa.gov/links/links.htm
Limited Life Item Status:
SRCA 10W Lamp #1: 203.6 of 500 hours
SRCA 10W Lamp #2: 177.8 of 500 hours
SRCA 10W Lamp #3: 180.6 of 500 hours
SRCA 10W Lamp #4: 57.7 of 500 hours
SRCA 1W Lamp #1: 500.2 of 5000 hours
SRCA 1W Lamp #2: 269.8 of 5000 hours
Solar Diffuser Door: 1776 of 3022 Movements
Nadir Aperture Door: 1050 of 1316 Movements
Space View Door: 629 of 1316 Movements