Terra Mission Status Update

Status Update Archive

April 20 - 26, 2007

Terra spacecraft and instrument subsystems are in nominal operations.

A GSFC team met April 26 to review the ASTER SWIR Compression Stroke Change proposed for May 2007. Representatives from Codes 300, 400, 500, Lockheed, Honeywell, and EOS alums presently on the JWST Project, listened to presentations from the Terra Mission Manager, ASTER instrument team, the spacecraft manufacturer, AETD experts (thermal, cryocooler, power, attitude, )and the Terra Flight Operations Team. The panel provided several tips and actions and gave a GO for the change in compressor stroke from 6 to 7 millimeters.

Agreement was reached on the first of two reconfigurations in response to a Terra Solid State Recorder (SSR) memory card that tripped offline Thursday April 19. The card was allocated to store MISR instrument science data. The first reconfiguration will move CERES and MOPPITT storage pointers into an area previously used for ASTER storage - this will restore 50% of the volume. A second reconfiguration to restore all the MISR volume is being finalized.

Terra Spacecraft Simulator (SSIM) 1 was successfully repaired, restored and validated by Terra FOT at approximately 6:00 PM Monday following an extended outage. Flight Software (FSW) System Administrator was able to restore the disk (ancient 1.2 GB) from the converted 4mm tape to 8mm in the FSW lab (Bldg. 1) and jointly with Hardware group resolved the final obstacle that turned out to be a SCSI bus address conflict. In addition, the SA has generated two copies of the 8mm tape and built a second spare disk image. The aging Terra Simulator contains custom hardware, obsolete components, and is likely to be unmaintainable.

Alaska Ground Station (AGS ) X-band receivers failed to lock onto science playback data on 4/23/07. The play back attempted was lost. As a result of not being able to empty the buffers, the MODIS and MISR buffers filled to capacity prior to the next science playback opportunity. MISR data loss: 113/19:52:06--20:19:29, 113/22:01:35--22:04:29. MODIS data loss: 113/19:52:22--20:01:23, 113/21:48:29--22:03:35.