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Significant Event Report for Week Ending 12/7/2001

Cassini Significant Event Report

For Week Ending 12/07/01

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday,
December 5. 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 autonomous
Command & Data Subsystem Solid State Recorder Memory Load Partition Repair and an Attitude Control
Subsystem high-water mark clear.

Execution of the C29 sequence continues to proceed normally, with the continued execution of Cassini's
Gravitational Wave Experiment (GWE). From the start in late November, 10 days out of 40 days of the
continuous GWE have been completed. Instruments other than Radio Science Subsystem remain in quiet
mode, and Magnetospheric and Plasma Science data continues to be collected and downlinked.

The Spacecraft Operations Office delivered version 7.1 of the Cassini Spacecraft Analysis Software. This
version of the ground software contains updates to the maneuver design tools required for the maneuver
automation software and updates to the Assisted Load Format tool to support critical sequence development.
In addition, the Command and Data Subsystem flight software team delivered revision 008 on the latest cycle
of Version 9 flight software. This delivery supports probe relay critical sequence development.
Mission Assurance completed the final edits to a Risk Management Paper for the 2002 IEEE Aerospace
Conference. The paper, Managing Risk for Cassini During Mission Operations and Data Analysis
(MO&DA), describes the Risk Management Process as developed and implemented for the MO&DA Phase
of the mission. The paper will be presented at the conference in March 2002.

The first input port for the C31 sequence science planning process occurred this week, in addition to the
delivery of the Target Working Teams' tour plans for orbits number four through ten.

The Attitude Control team held a peer review of the new energy based smart burn algorithm for Saturn Orbit
Insertion. The board endorsed the team's design approach and technical assessment while recommending that
the development schedule be re-examined to provide more margin and time for testing the new algorithm. The
team is currently assessing the fourteen Requests For Action forms submitted at the review as well as
reviewing the development schedule.

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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