Terra Weekly Mission Status Update 7-13 Sep 2001

The Terra spacecraft is in nominal mode. All instruments are in nominal science mode.

Instrument operations are continuing smoothly on all 5 instruments. A MODIS Calibration Roll Maneuver was successfully executed on September 7. A Drag Make-up maneuver was successfully executed on September 13. The burn parameters were recalculated one day prior to execution to compensate for fluctuating changes in atmospheric drag resulting from varying sunspot activity. This resulted in a “conservative” burn that will likely necessitate the next Drag Make-up maneuver in approximately 3 weeks.

The Terra Flight Operations Team successfully scheduled and utilized contacts at the Polar Ground Stations to acquire Solid State Recorder playbacks of science data via X-band to compensate for a gap in TDRSS coverage resulting from a scheduled system maintenance-related outage at STGT.

Ground testing with the commercial ground terminals at Svalbaard (SKS) and Alaska (PF1) is continuing. Efforts continue to isolate the 6 bytes of data that are being appended to each command issued from the EOS Operations Center (EOC). This must be fully diagnosed prior to performing any tests involving the issuing of NO-OP commands to Terra via these new ground stations.

Several MDA2BITE trips (High Gain Antenna Motor Drive Assembly opto-coupler Single Event Upsets) occurred during this reporting period with no resultant non-recoverable data loss.

Plans:

• Next MODIS Calibration Roll Maneuver on October 7, 2001
• Planning for Leonid Meteor Shower (on November 18, 2001) in progress