Cassini Significant Event Report

For Week Ending 07/28/00

On July 11, Cassini passed 1000 days of flight.

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, 07/26. 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.

Activities this week include Magnetometer Subsystem (MAG) sensor offsets,
Composite Infrared Spectrometer (CIRS) performance tests, Visual and Infrared
Mapping Spectrometer (VIMS) dark frames and calibration, the completion of
the Magnetospheric Imaging Instrument (MIMI) functional test, and
participation by CIRS, Cosmic Dust Analyzer (CDA), Cassini Plasma
Spectrometer (CAPS), MAG, Radio and Plasma Wave Science (RPWS), MIMI,
Ultraviolet Imaging Spectrometer (UVIS), VIMS and Imaging Science
Subsystem (ISS) in the quiet test. During the quiet test all the
instruments are on and operating. Each instrument takes a turn running in
its "nosiest" mode while the other instruments listen. Analysis will be
performed to determine the impact on data collection. This information
will be invaluable during tour when different combinations of instruments
will be operating at different times.

The Preliminary Sequence Integration and Validation Phase has begun for
the Cruise sequence 22.

An Orbiter Science Operations Working Team (OSOWT) telecon was held to
continue the integration process for the last science sequence in the
Jupiter Subphase, C25. The C25 sequence covers the period from Jupiter
closest approach +72 days to +120 days. The Jupiter science observations
will end on +82 days. The Project Briefing on C25 is scheduled for mid

The Command and Data System Team held a successful Software Requirements
and Certification Review for Version V7.0_011 of the new CDS flight
software. This software provides significant new capabilities in data
processing and Solid State Recorder management. The development and test
program satisfied all requirements for the delivery of the software. The
ground activities that will uplink the new software and perform an
in-flight checkout will begin next week.

The remote terminal simulator (RTSIM) rack, part of the Integrated Test
Laboratory (ITL) fidelity enhancement upgrade, was installed in the ITL.
Integration and checkout activities are underway.

A Delivery Coordination Meeting (DCM) was held this week for CSAS 5.0.
Updates to the Kinematic Prediction Tool (KPT) and Inertial Vector
Propagation (IVP) were delivered. The delivered version has been
installed in the Verification and Validation (V&V) area for Spacecraft
Office (SCO) system testing.

A DCM was also held for Navigation (NAV) J2 software. This delivery
augments the last delivery and provides a number of new capabilities for

System Engineering completed the final Post Jupiter Mission
Planning/Science Planning Operations Concept and is in the process of
distributing it.

Over the last several months the Distributed Object Manager (DOM) Working
Group (comprised of representatives from all the Cassini teams) has been
designing upgrades to enhance the operability of the DOM for Cassini, and
to allow for phasing out of the Central Database by September. These
changes were implemented over the weekend. They focus around schema
changes that allow publishing of Spacecraft, Planet, Instruments,
C-matrix, and Events kernel (SPICE) files and the new Reaction Control
Subsystem (RCS) Delta V file type created for Attitude and Articulation
Control Subsystem/Navigation (AACS/NAV), a separate volume for the
publishing of extremely large Predicted Events File (PEF) files generated
by Science Planning, and the modification of sequence identification
fields and tables.

Cassini Outreach made numerous presentations this week including two
one-hour presentations of classroom activities at the teacher conference
attached to the annual meeting of the Astronomical Society of the Pacific,
Universe 2000, and presentations to the Astronomical League annual
convention, ALCON 2000.

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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