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JET PROPULSION LABORATORY
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Mission controllers successfully commanded the spacecraft to resume normal operations Friday evening, March 19, after Stardust entered a low-activity "safe" state the night before. Stardust's main computer had indicated it was carrying out an excessive number of functions during testing of the navigation camera and transmission of its images to Earth on Thursday, triggering fault protection software that placed the spacecraft in a low-activity state. When the spacecraft is flown in this "safe" mode, all non- critical activities are halted and the spacecraft points its antenna toward Earth and awaits new commands.

Controllers waited until the next telecommunications opportunity on Friday evening to resume contact with Stardust. Communications with the spacecraft were resumed as expected and the spacecraft was commanded to proceed with normal operations. Engineering data was received from the spacecraft, and the team is performing detailed analysis of the data to determine what activities or software could have led the spacecraft computer to trigger fault protection that placed Stardust in its temporary safe state.

Last week, the spacecraft successfully exercised the mirror on the navigation camera for the first time, moving the device outward 90 degrees and back. The mirror will allow the navigation camera to gather close-up images of heart of Comet Wild-2 without being struck by debris that will be flying off the comet's nucleus. Stardust encounters the comet in 2004.

Mission scientists were surprised and pleased last week with Stardust's exceptionally steady orientation in flight. Data from the navigation camera showed that the spacecraft's "drift," or the balancing adjustments it makes to maintain its orientation in space, was about 10 times less than anticipated. This is good news for scientists using the navigation camera, because the steadier the spacecraft, the clearer its images because there will be less smearing due to motion.

The principal investigator for the Stardust mission is Dr. Donald C. Brownlee of the University of Washington. The mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Space Science, Washington, DC. The spacecraft was built and is operated by Lockheed Martin Astronautics, Denver. Its instruments were provided by the Jet Propulsion Laboratory, the University of Chicago, and the Max Planck Institute, Garching, Germany.

JPL is a division of the California Institute of Technology, Pasadena, CA.