Significant Event Report for Week Ending 12/21/2001

Cassini Significant Event Report

For Week Ending 12/21/01

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, December 19. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the spacecraft's position and speed can be viewed on the "Present Position" web page.

Recent instrument activities included two Radio and Plasma Wave Science High Frequency Receiver calibrations. Engineering activities taking place onboard the spacecraft this week include an Attitude Control Subsystem (ACS) high-water mark clear and a reset of the Reaction Wheel Assembly (RWA) revolution readings.

Execution of C29 continues to proceed normally with the ongoing Gravitational Wave Experiment, of which 23 days out of 40 days have been completed. Spacecraft health remains excellent, maintaining a quiet spacecraft on RWA control. Instruments remain quiet as well with MAPS data being collected and downlinked.

In support of the C30 sequence development, the "D" revision of the background and minisequence products were released for review.

Tour Science Planning continues to make progress, with the final science team input port for the Satellite Orbiter Science Team (SOST) Science Uplink Verification (SUPV) activity occurring this week. The merged products from this port will be sent to the ACS team for spacecraft pointing analysis. The SOST SUPV activity is the second of three SUPV activities scheduled to work through the tour planning process and familiarize the Science Planning team with the tools, processes, and constraints involved.

Mission Assurance issued a status report to the Office of Safety and Mission Assurance, with the Cassini Flight Operations Status listed as "green."

Two Delivery Coordination Meetings were held in support of the Cassini Information Management System (CIMS) 2.0 and Mission Sequence Subsystem (MSS) D7.7 deliveries. CIMS 2.0 provides for export of the " Solid State Recorder (SSR) Data Class" parameter to other Science Planning tools, improved time-ordered listing formatting, and significant infrastructure enhancements to speed processing and ease Science Planning workload. The MSS D7.7 delivery includes the first release of the SSR Management Tool as well as a new Main Engine Trajectory Correction Maneuver (TCM) block for TCM 18.

Additional information about Cassini-Huygens is online at http://saturn.jpl.nasa.gov.

Cassini will begin orbiting Saturn on July 1, 2004, and release its piggybacked Huygens probe about six months later for descent through the thick atmosphere of the moon Titan. Cassini-Huygens is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Office of Space Science, Washington, D.C.

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