Skip to main content

MCST Banner Image

am1weekly_2003-298_2003-304

Mission Operations Days: 2003/298 to 2003/304
October 25, 2003 00:00:00 GMT to October 31, 2003 00:00:00 GMT


Terra Spacecraft and MODIS Instrument Status:

AM-1 "Terra" is in Normal Mode
PFM MODIS is in A-Side Nominal Science Mode
(Cross Strapped with FR B)
Component State(s) Comment
Blackbody A On (290K); B Off Nominal Science Mode
Calibration Electronics A On; B Off Nominal Science Mode
Control Processor A On; B Off Nominal Science Mode
Nadir Door Unlatched, Open Nominal Science Mode
Space View Door Unlatched, Open Nominal Science Mode
Solar Diffuser Door Unlatched, Screened Permanent Configuration
FDDI Formatter A On; B Off Nominal Science Mode
FDDI Port A On; B Off Nominal Science Mode
FIFO Memory #1 & #2 On; #3 & #4 Off Nominal Science Mode
Format Processor A Off; B On Nominal Science Mode
Power Supplies #1 On, #2 Off Nominal Science Mode
PV VIS FPA A On; B Off Nominal Science Mode
PV NIR FPA A On; B Off Nominal Science Mode
PV SMIR FPA A On; B Off Nominal Science Mode
PV LWIR FPA A On; B Off Nominal Science Mode
PC LWIR FPA A On; B Off Nominal Science Mode
RC Outgas Heaters All 3 (CS, IS, OS) Off Nominal Science Mode
RC LWIR FPA Heater On (83K) Nominal Science Mode
RC SMIR FPA Heater Off Nominal Science Mode
Scan Assembly A On; B Off Nominal Science Mode
SDSM Off Nominal Science Mode
SRCA Off Nominal Science Mode
PS1 Survival Heater Enabled Nominal Science Mode
PS2 Survival Heater Enabled Nominal Science Mode
Timing Generator A On; B Off Nominal Science Mode
Flight Software Rev BD + 11 sets of patches
  • CP07 to Survival Mode - No SDD to closed command (1 patch)
  • CP07 to Safe Mode - No FR OFF Command (1 patch)
  • CP07 to Safe Mode - No SDD to closed command (1 patch)
  • CP07 to Science Mode - Turn on FRB instead of FRA (1 patch)
  • CP07 to Outgas and Science Mode - Turn on FRB instead of FRA (1 patch)
  • FR Error Counting and Statistics (2 patches)
  • FR 1000ms time code patches (3 patches)
  • FR Band 5 Gain Change (20 commands)
  • FR BB Ideal Output Values (1 patch)
  • FR A EEPROM KME Fast 1 word patch (1 patch)
  • FR B EEPROM KME Fast 1 word patch (1 patch)
Nominal Science Mode
Inhibit Ids Set none Nominal Science Mode
TMON 66 Disabled Nominal Science Mode
TMON 67 Disabled Nominal Science Mode
TMON 68 Enabled Nominal Science Mode
TMON 69 Disabled Nominal Science Mode

This Week's Completed MODIS Activities:

Saturday, October 25, 2003

None

Sunday, October 26, 2003

None

Monday, October 27, 2003

2003/300 12:29:09-12:31:40 ATC MOD_OA27_PV_ECAL.3 OA-27: PV Electronics calibration
2003/300 14:40:00-14:40:31 ATC MOD_SRCA_NOMINAL_SETUP.4 Setup of nominal lamp configuration for SRCA calibration
2003/300 14:45:29-16:54:22 ATC MOD_OA20_SRCA_10W_RAD_Base.1 OA-20: 10W Radiometric (Radiance feedback w/ND) Data collect: 15:04:59-16:54:22
2003/300 21:21:01-23:29:54 ATC MOD_OA21_SRCA_1W_RAD_A.3 OA-21: 1W Radiometric Continuous (Radiance feedback) Data collect: 21:40:31-23:29:54

Tuesday, October 28, 2003

2003/301 21:25:03-21:35:51 ATC MOD_OA16_SDSM_SCRN_NO_DOOR_A.4 OA-16: SD/SDSM screened side A, no door movement.

Wednesday, October 29, 2003

2003/302 01:00:00 ATC MOD_OA26_BB_270K_A.1 Set blackbody temperature to 270K on the A Side
2003/302 19:00:00 ATC MOD_OA26_BB_280K_A.1 Set blackbody temperature to 280K on the A Side
2003/302 23:00:00 ATC MOD_OA26_BB_285K_A.1 Set blackbody temperature to 285K on the A Side

Thursday, October 30, 2003

2003/303 02:00:00 ATC MOD_OA26_BB_290K_A.1 Set blackbody temperature to 290K on the A Side
2003/303 06:00:00 ATC MOD_OA26_BB_315K_A.1 Set blackbody temperature to 315K on the A Side
2003/303 06:00:30 ATC MOD_OA26_BB_DCYCLE_FULL.1 Set blackbody heater duty cycle to FULL
2003/303 09:00:00 ATC MOD_OA26_BB_270K_A.1 Set blackbody temperature to 270K on the A Side
2003/303 09:00:30 ATC MOD_OA26_BB_DCYCLE_THIRD.1 Set blackbody heater duty cycle to THIRD

Friday, October 31, 2003

2003/304 06:00:00 ATC MOD_OA26_BB_290K_A.1 Set blackbody temperature to 290K on the A Side

This Week's Scheduled MODIS Activities Not Completed:

None

Upcoming MODIS Events:

Calibrations for November include bimonthly SRCA Full Spatial, monthly SRCA Full Radiometric, monthly 10W Radiometric, and weekly SD/SDSM. In addition, a full set of memory table dumps will be gathered.

Tuesday, November 4, 2003

2003/308 21:31:41-21:40:29 ATC MOD_OA16_SDSM_SCRN_NO_DOOR_A.4 OA-16: SD/SDSM screened side A, no door movement.

Maneuvers:

The next Lunar Roll Calibration would occur on DOY 2003/218 (November 14, 2003). The maneuver has been declined based on concerns over predicted Leonid Meteor Shower activity.

Terra performed a DMU on Friday, October 31, 2003 (DOY 2003/304) at 18:13:33 GMT.

MODIS Anomalies:

Terra Solid State Recorder Anomaly

Although not directly the result of a MODIS problem, the most recent Printed Wire Assembly (PWA) failures in the Terra Solid State Recorder (SSR) do affect MODIS data. See the Non-MODIS Significant Events section below for more details.

General Instrument Comments:

MODIS is in Science Mode, using all A-side components, but cross-strapped to Formatter B, with the blackbody maintained at 290K and the Solar Diffuser Door at the Screened position.

MODIS Telemetry Trends:

Nominal telemetry trending is ongoing.

Non-MODIS Significant Events:

Solar Flare Activity

In the last week, Solar Flare Activity has increased and has had a notable effect on Terra. Numerous hits to the High Gain Antenna's (HGA) Motor Drive Assembly (MDA) have occurred resulting if occasional loss of communications. Science Data playbacks have suffered small losses. A complete count of the HGA MDA hits and science data lost is still being ascertained. Additionally, the Magnetic Torquer rods have been saturating while Terra travels over the North Pole. The Momentum Wheels have had to compensate to unload the extra momentum. As of yet, no changes have been necessary in GN&C operations.

Terra Solid State Recorder Anomaly

Overview:

The SSR Anomaly is still under investigation. MODIS currently is operating with 34 Supersets allotted for its buffer. There are currently no plans for power cycling the failed PWAs. There are no current plans for a change in science data capture rates.

Details:

Two Printed Wire Assemblies (PWA) in the Terra Solid State Recorder (SSR) have autonomously powered- down. The first shut down on September 24, 2003 (2003/267) at approximately 23:10 GMT. This PWA contains supersets #50 and #51 that are assigned as MODIS buffer locations. The second PWA shut down September 25, 2003 (2003/268) at 07:30 GMT. This second PWA contains supersets #114 and #115 that are assigned to the ASTER instrument. It is believed that over-current protection circuits in each PWA caused the PWA shutdowns.

The data written to these supersets while they were powered off are not recoverable. The four failed supersets were moved to the "bad" list and will no longer have data written to them. This reduced MODIS' total SSR buffer space from 36 supersets to 34 supersets and resulted in a short data loss while the transition was made.

Note that MODIS started the mission with 35 supersets of SSR space. A similar PWA failure occurred in May of 2001 (supersets #30 and #31) with the net result of MODIS gaining 1 superset (up to 36) when the SSR was recycled in June of 2001. It is believed that recycling the SSR will return all of the failed SSR supersets (currently 6) to working operation.

The final SSR playback before the PWA re-assignment was at 18:06:15 GMT on September 25, 2003 (2003/268). Science data recording to the SSR was stopped at 18:36:54 and re-enabled at 18:51:14. During this time, there will be no MODIS science data. For the period between 18:06:15 and 18:36:54, some or all of that MODIS data may be lost as well. The exact amount is not known at this time.

One superset was moved from the MISR buffer to the MODIS buffer at 12:22:17 GTM on September 30, 2003 (2003/273). This brings the count of supersets in the MODIS buffer to 35, its original count from mission start. Science Data recording during the reassignment was disabled between 12:16:29 and 12:28:25 GMT.

Another PWA failure occurred at 03:03 GMT on October 14, 2003 (2003/287). Both supersets in this PWA were allotted to the MODIS buffer. The two supersets (#42 and #43) in the failed PWA were removed from use later that day in the period 2003/287 19:07-19:14 GMT. During that time, science data recording was disabled. After that time, the MODIS allotment of supersets on the SSR became 33.

On Monday, October 20, 2003 (DOY 293) at 13:37:51, the FOT reassigned one of MISR's allotted supersets (#3) to the MODIS list, bringing the MODIS superset count to 34 and MISR to 18.

At this time, there are no plans to power-cycle the SSR to (hopefully) return all of the PWAs to working order because of other potential risks to the SSR during a power-cycle. The MODIS IOT has been asked to consider reducing its Science Data rate from the current orbital collection of 50% Day/50% Night to a 45/55 or 40/60 Day/Night rate. Such a reduction would aid the FOT in their replay management of the SSR buffers. Currently there are no plans to make this reduction. However, the MODIS IOT is taking steps to be prepared to support such a request, should it occur in the future. Additionally, further superset reassignments by the FOT to balance Science Data storage may be necessary, should additional PWA losses occur.

A brief timeline of the command activities follows:

Wednesday, September 24, 2003

2003/267 23:12:00 SSR PWA containing supersets 50 & 51 (MODIS) shut down

Note: About 5-1/2% MODIS data is lost until the supersets are moved to the "bad" list

Thursday, September 25, 2003

2003/268 07:37:00 SSR PWA containing supersets 114 & 115 (ASTER) shut down
2003/268 18:06:15 Last SSR playback before re-assigning failed supersets to the "bad list"
2003/268 18:36:54 Science recording to the SSR is disabled
2003/268 18:51:14 Science recording to the SSR is re-enabled

Note: Science data loss occurred while the recording was disabled. Some or all of the data since the last SSR playback may be lost as well.

Tuesday, September 30, 2003

2003/273 12:16:29 Science recording to the SSR is disabled
2003/273 12:17:25 Housekeeping recording to the SSR is disabled
2003/273 12:22:17 One MISR superset moved to MODIS
2003/273 12:28:25 Science recording to the SSR is re-enabled
2003/273 12:29:24 Housekeeping recording to the SSR is re-enabled

Tuesday, October 14, 2003

2003/287 03:03:00 SSR PWA containing supersets 42 & 43 (MODIS) shut down
2003/287 19:07:08 Science recording to the SSR is disabled
2003/287 19:14:15 Science recording to the SSR is re-enabled

Monday, October 20, 2003

2003/293 13:28:02 Science recording to the SSR is disabled
2003/293 One MISR superset moved to MODIS
2003/293 13:37:51 Science recording to the SSR is re-enabled

The EMOS mission status webpage (which includes instrument data loss records) can be found at the following URL. Note that a password is now required to access the EOS mission links web pages. There are directions at the URL below for how to obtain a username/password.

http://jupiter02.gsfc.nasa.gov/links/links.htm

Limited Life Item Status:

SRCA 10W Lamp #1: 221.9 of 500 hours
SRCA 10W Lamp #2: 163.0 of 500 hours
SRCA 10W Lamp #3: 172.2 of 500 hours
SRCA 10W Lamp #4: 62.2 of 500 hours

SRCA 1W Lamp #1: 564.6 of 4000 hours
SRCA 1W Lamp #2: 276.7 of 4000 hours

Solar Diffuser Door: 2146 of 3022 Movements
Nadir Aperture Door: 536 of 1316 Movements
Space View Door: 439 of 1316 Movements