Cassini Significant Event Report

For Week Ending 09/01/00

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, 08/30. The Cassini spacecraft is in an
excellent state of health and is operating normally. The speed of the spacecraft can be viewed on the "Where is Cassini Now?" web page.

The checkout of the new Command and Data Subsystem (CDS) flight software
concluded this week with the successful completion the SSR management and
telemetry mode demonstrations and the loading of the emergency RAM. The
Periodic Engineering Maintenance (PEM) sequence was executed. PEM activities
included Backup ALF Injection Loader (BAIL) maintenance, Engine Gimbal
Actuator (EGA) and Reaction Wheel Assembly (RWA) exercises.

The C21 instrument power-on and IEB load mini-sequence was approved for
uplink to the spacecraft next week. The Preliminary SIV Approval Meeting
was held for C22 A Sequence Change Request approval meeting was held for
C23 and formally approved one change requested by SCO (AACS).

A Jupiter System Assessment Meeting was held to mark the formal completion
of development for the Jupiter phase.

The Instrument Operations Team Requirements and Design Review for the Tour
Phase occurred this week. The review board gave the team high marks for
the material presented.

An update to the Mission Sequence System was delivered to correct a
problem with the C-kernel output file in the Pointing Design Tool.
Installation on the Science Operations and Planning Computers at the
remote science sites was completed later in the week.

A briefing was given to Program Management regarding status of and current
challenges in development of the Science Opportunity Analyzer, Pointing
Design Tool, and Cassini Information Management System software tools.

ULO personnel have proposed a revised sequence development schedule for
the post-Jupiter time frame. The new schedule reduces the process to
eight weeks by eliminating the overlap of sequence development and
execution. This process improvement should result in more efficient

A preliminary version of the MSSO Functional Requirements Document (FRD)
has been released for review. This document will form the basis of the
MSSO Requirements and Design Review planned for September.

User access to the Central Database (CDB) was terminated this week with
decommissioning of the CDB scheduled for mid-September. The CDB has been
replaced by the TMOD provided Distributed Object Manager (DOM) system.

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.

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