Cassini Significant Event Report

For Week Ending 07/27/01

The most recent spacecraft telemetry was acquired from the Canberra
tracking station on Wednesday, July 25. 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 spacecraft activities include clearing the Attitude Control
Subsystem (ACS) Highwater Marks, a Command & Data Subsystem Solid State
Recorder Memory Load Partition repair, testing of the Radio and Plasma
Wave Science (RPWS) Instrument Expanded Blocks, and an RPWS High Frequency
Receiver calibration. The Spacecraft Operations Office (SCO) performed two
ACS Reaction Control Subsystem Controller tests to investigate possible
ways to decrease thruster cycles and hydrazine use. The SCO team also
completed the first of three instrument muting tests in support of future
Huygens Probe checkouts.

A Delivery Coordination Meeting was held for version 4.1 of the Visual and
Infrared Mapping Spectrometer Flight Software. The delivery was accepted
and the software released for testing in the Integrated Test Laboratory,
with a planned uplink in late August.

Training was conducted for team members from Instrument Operations,
Composite Infrared Spectrometer, Imaging Science Subsystem, and Mission
Support & Services Office. Classes introduced personnel to the Cassini
Help Desk; Science Opportunity Analyzer; the JPL Problem Reporting System;
the Uplink Process; Spacecraft, Planet, Instruments, C-matrix, and Events
(SPICE) kernels; and Cassini's Distributed Object Manager file repository.

The Cross-Discipline and Magnetosphere Target Working Teams met to discuss
the integration of the Tour segments allocated to these teams.

Cassini management staff supported a meeting with a subset of the board
from the NASA Independent Annual Review to discuss board findings.

Two new Cassini slide sets have been posted on the web. "A Trip to Saturn"
chronicles the assembly, launch, and journey of Cassini-Huygens to the
Saturn System. "The Saturn System" is a compilation of images of Saturn,
its moons, rings, and magnetospheres as seen by Voyager and the Hubble
Telescope. "A Trip to Saturn" and "The Saturn System" slides can be
viewed at:


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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