Cassini Significant Event Report

For Week Ending 11/28/03

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Monday, November 24. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at .

On-board activities this week included Radio and Plasma Wave Science High Frequency Receiver calibration, uplink and execution of a Magnetospheric Imaging Instrument (MIMI) event filter mini-sequence, uplink of the MIMI Instrument Expanded Block (IEB) load and data rate throttle down Immediate/Delayed Action Program, uplink and load of a Composite InfraRed Spectrometer IEB, uplink and execution of a Cosmic Dust Analyzer (CDA)High Rate Detector checkout mini-sequence, and an SSR repair.

The Radio Science team continues to collect coherent X-band data and, when available, Ka1 data as part of the continuing Gravitational Wave Experiment #3 (GWE). Deep Space Station 55 provided its first support for GWE#3 this week. The station became operational on November 1st, 2003, and is equipped with Ka-band receive capability. This means that both X-band and Ka1 data can be acquired. Support was provided for three consecutive days with a final pass planned for Wednesday of this week.

At the request of the Cassini Project Scientist, investigators from Boston University have been granted observing time on the Hubble Space Telescope to view Saturn's aurora around the time of Saturn orbit insertion next July. This effort will be in conjunction with the Cassini spacecraft's measurement of the solar wind impinging upon the Saturnian system. The aurora are believed to be caused by interactions between the solar wind, the Saturnian magnetosphere, and the atmosphere of Saturn itself.

Official port 1 deliveries were made as part of the Science Operations Plan Implementation process for tour sequences S19 and S20.

The Science Planning Team process for Cruise sequence C43 concluded this week. A handoff package was passed to Uplink Operations to support the sequence generation process that will begin next week.

The C42 Preliminary Sequence Integration and Validation (PSIV) phase 1 science and sequence update process package was released for review as part of the C43 sequence development process. The PSIV 1 Sequence Change Request /Sequence approval meeting will be held next week.

The Spacecraft Operations Office delivered ground software tools RBOT V2.0 and FSDS V2.17. RBOT is a tool used by the AACS team to bias the reaction wheels to minimize low speed wheel time. FSDS is an AACS flight software simulation program used to validate and verify AACS flight software.

A delivery coordination meeting was held for Command Database version D10B. This version includes command changes for CDA, INMS, and MIMI, and is planned for use with Mission Sequence Subsystem D10.2 to be delivered in March of next year.

Mission Assurance met with the Aerospace Corporation as part of an ongoing JPL/Aerospace collaboration to further the practice of Risk Management. Slides were produced to document the status of the collaboration effort to date, including data gathering and inputs to a Risk Management Storybook. The joint working group is scheduled to present the status and results to date at next year's Space Systems Engineering and Risk Management Symposium, scheduled for 17-20 February 2004.

Additional information about Cassini-Huygens is online at

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.

Media Relations Office

Jet Propulsion Laboratory

California Institute of

National Aeronautics and Space

Pasadena, Calif. 91109.
Telephone (818) 354-5011