Significant Event Report for Week Ending 12/11/1998

Cassini Significant Event Report

For Week Ending 12/11/98

Spacecraft Status:

The most recent Spacecraft status is from the DSN tracking pass on
Thursday, 12/10, over the Goldstone tracking station. The Cassini
spacecraft is in an excellent state of health and is executing the Cruise
11 sequence normally. The speed of the spacecraft can be viewed on the
"Where is Cassini Now?"
web page (../../operations/present-position.cfm).

Spacecraft Activity Summary:

On Friday, 12/04, data was played back from the very successful Deep Space
Maneuver. Following this, the record and playback pointers were reset as
planned.

On Saturday, 12/05, the oxidizer side of Propulsion Module Subsystem (PMS)
was successfully isolated by closing pyro valve PV24. This was a planned
activity as part of the post Deep Space Maneuver (DSM) reconfiguration.

On Monday, 12/07, part two of the Cruise 11 sequence was successfully
uplinked to the spacecraft. Following this activity, a calibration was
initiated on the attitude control Stellar Reference Units (SRUs) but was
halted by AACS fault protection. Flight engineers are investigating the
cause for the test interruption. Once the cause is understood, the
calibration test will be rescheduled.

On Wednesday, 12/09, the AACS High Watermarks were cleared.

On Thursday, 12/10, an update was performed to the Active IVP Vector to
correct for the change in the trajectory due to the successful completion
of the DSM. A post DSM update was also made to the on-board mass
properties stored in AACS software. These are the final activities
associated with the post DSM reconfiguration.

Upcoming events:

Activities scheduled for the week of 12/11-12/18 include an SSR Pointer
Reset on 12/11, a Periodic Engineering Maintenance (BAIL and EGA portions)
on 12/13, SSR FSW Partition Maintenance on 12/16, and Instrument flight
software updates for CDA, CIRS, and RPWS on 12/17.

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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