Cassini Significant Event Report

For Week Ending 03/24/00

The most recent spacecraft telemetry data was acquired from the Madrid
tracking station on Wednesday, 03/22. 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 Spacecraft Team spent this week monitoring the Cassini spacecraft and
gathering performance statistics for the orbiter while under reaction wheel
control. This is the last activity as part of the AACS version A7 Flight
Software checkout. All tests have completed nominally and the team is very
pleased with spacecraft performance.

Educational Outreach made presentations to 300 2nd graders and 14 of their
teachers, and to 120 8th graders and their 2 teachers at schools in Granby,
CT. Additional presentations were made to more than 50 representatives of
NASA's Educator Resource Center Network, showing various Cassini classroom
demonstrations and activities.

The Titan Orbiter Science Team (TOST) met to formulate an allocation plan
based on the RADAR experiment acquiring 20% and 25% surface coverage on
Titan and understanding the implications to the other science instruments
for these plans. The group succeeded in developing the proposed plans and
learning the trades between the instruments in accommodating the minimum
RADAR surface coverage requirements.

A Project Briefing was held on the Jupiter Science Phase C and D portion of
the Jupiter Subphase. (-25 days from Jupiter closest approach to Jupiter
closest approach.) The purpose of the meeting was to review the Phase
contents in detail and obtain the Project Manager's approval to begin the
Science Planning Virtual Team's (SPVT) implementation of this Phase. A
follow up meeting has been scheduled to further discuss the issues before
approval is given for this Phase.

The Satellite Orbiter Science Team (SOST) met to begin the integration of
observations of the icy satellite flybys in the Saturn Tour. At the
meeting the science instruments provided their observational desires for
the Iapetus flyby in the Tour. Assignments were given to work the
integration issues for this flyby, and the observational desires for other
satellite flybys were discussed.

A coordination meeting for MSS D7.1 OPS testing was held. This delivery is
for the SUN workstations, and provides a new command database and
corresponding update to SEQ_GEN, the first delivery of Power Predictor,
APGEN for Solaris V2.5 and 2.6 (provides capability comparable to the HP
version), and PDT with new functionality.

The Engineering build of HSS (High Speed Simulation) with the new CDS &
AACS FSW has been received, installed, and is undergoing TMOD testing. It
is still on track for the scheduled 4/05/00 delivery.

The Distributed Object Manager (DOM) Science Operations and Planning
Computer (SOPC) User's Guide has been distributed locally and to the remote

A flight software upgrade was approved for the Visual and Infrared Mapping
Spectrometer Subsystem (VIMS). RADAR installed a "beta" version of CASPER
on the SOPC and produced C-kernel files for Titan Science Planning. RADAR
also utilized the Pointing Design Tool (PDT) and appropriate modules for
the first time for the C22 ICO-2 observations. This was a valuable
exercise in testing tour planning tools.

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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