From: Goddard Space Flight Center
Posted: Sunday, August 10, 2003
The Terra spacecraft is in nominal mode. All instruments are in Science Mode.
The MODIS Solar Diffuser Screen Anomaly Investigation Team conducted a review on the results of the instrument manufacturer's (Raytheon-Santa Barbara) thermal analysis on June 25, including a panel of scientists and engineers separate from the Anomaly Investigation Team. A subsequent review of the analysis by Code 300 and the AETD Chief Engineer provided concurrence with the recommendation to command the Solar Diffuser Door open permanently with the screen closed to restore the calibration capability for the ocean color bands. Calibration for the other affected bands will be performed by the MODIS Calibration Science Team through modeling. Modeling enables extrapolation of the results of previous calibrations and the trends of known changes in the response for the affected bands over the course of the last 3.5 years on orbit.
A Command Authorization Meeting (CAM) for the door re-opening was conducted by the operations team on Friday, June 27, in association with the plan to reopen the door on Wednesday, July 2. The MODIS door was successfully commanded open at 1:53 p.m. EDT on Wednesday, July 2. The instrument and solar diffuser will be monitored closely and analysis will continue on the mechanism, observed thermal excursions, and root cause. A closeout incident report will be filed subsequent to receipt of a follow-on report from the instrument manufacturer.
A Command Authorization Meeting (CAM) for the first in series of three inclination adjust maneuvers was also held on July 2.Plans
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