Mission Status 2009
Tim Larson Stardust Spacecraft Team
May 6, 2009
The spacecraft is healthy and operating on background sequence SN023 until May 17. The attitude determination and control, propulsion, and navigation teams report that the fuel consumption after the thruster string swap is slightly less than expected, and will continue to monitor the thruster firings and small forces data to observe long term trends. The project is preparing for the Science Team meeting and Comet Rotation Modeling workshop on June 8 and 9 at Cornell University.
April 29, 2009
The spacecraft is healthy and operating on background sequence SN023. Thruster string 2 continues to provide control and is operating smoothly. A periodic cleanup and consolidation of on board memory was performed this week to improve the memory access performance. Flight software analyzed the memory dumps and confirmed the desired file system configuration on board the spacecraft.
April 22, 2009
The spacecraft is healthy and operating as expected after the thruster string swap that was commanded on April 20. After 10 years of operation, the primary string had far exceeded their qualified number of pulses, although no measurable degradation had been noted. The swap was commanded after approval from senior management and the Discovery Program Office. The string 2 RCS thrusters are now controlling spacecraft attitude, and no significant change in fuel usage has been noted.
April 15, 2009
The spacecraft is healthy and shows signs of improved attitude controller efficiency after the recent parameter update. A review was held on April 13 with senior management to review the aging RCS thrusters on the spacecraft. Preliminary approval was given for a swap to the backup string pending completion of two action items, both of which are expected to be completed by the end of the week.
April 8, 2009
The spacecraft continues in cruise with all subsystems operating as expected. The new attitude control parameters have been uploaded and the team will be looking for signs of increased efficiency in propellant usage.
April 1, 2009
Stardust had one contact this week. The next pass is tomorrow, Thursday, April 2. All subsystems are operating nominally. An updated deadband controller will be used beginning tomorrow. The update will improve the controller's response when commanding thruster pulses with noise in the star camera measurements. In response to the aging RCS thrusters, the team has prepared commands to use 4 backup control thrusters. The commands have been built and a thorough test program is underway. A meeting has been scheduled with JPL institutional management to obtain approval for this swap.