Cassini Significant Event Report

For Week Ending 06/29/01

The most recent spacecraft telemetry was acquired from the Madrid tracking
station on Wednesday, June 27. 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 included a Radio and Plasma Wave Science
(RPWS) high frequency receiver calibration and an automatic repair of
solid state recorder B. An additional test of the Huygens Probe B-chain
S-band carrier signal was performed this week; Huygens personnel are
currently analyzing the data returned from this activity. The Visual and
Infrared Mapping Spectrometer (VIMS) was powered on and initialized with
flight software and an Instrument Expanded Block (IEB) load in preparation
for the start of the C27 background sequence. Additionally, a minisequence
was uplinked to provide a revised IEB load for the Imaging Science
Subsystem (ISS) in preparation for its next observation.

The Cassini Project Science Group (PSG) meeting was held in Oxford,
England. The PSG endorsed a scenario which permits full retrieval of
Huygens Probe data. The details of this scenario, which includes a Titan
flyby at 50,000 to 70,000 km for probe release, will be worked in the
coming months. Cassini science teams presented science results from the
Jupiter flyby in December of last year. Plans are under way for
publication of these results in scientific journals. Saturn planning was
a key focus of the meeting. Highlights included discussions of the first
10 Titan flybys and numerous icy satellite flybys, and the formation of
Target Working Teams. These teams will address more detailed tour issues
such as synergistic observation strategies, data volume, and other aspects
of planning that are needed for the development of the Science Operations
Plan. Additionally, personnel from the Uplink Operations Team provided
the PSG with an overview and led a discussion on science planning tools.

The C27 Sequence Virtual Team worked with Integration Test Laboratory
personnel to perform a system test of instrument muting capabilities in
support of the C27 Huygens Probe mute test. All results were nominal.

The Spacecraft Operations Office began a series of meetings to update the
Main Engine Trajectory Correction Maneuver block for TCM-18 and for Tour.¿

A dedicated test network has been implemented by the Mission Support &
Services Office which allows testers and system administrators to
troubleshoot problems, test new software installations, and monitor

A series of five student workshops on Cassini were given in workshops
co-sponsored by Sandia National Laboratory and Los Alamos National
Laboratory. A public lecture was also given at the Bradbury Science
Museum in Los Alamos. This outreach activity was targeted at students
throughout the state of New Mexico.

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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