Cassini Significant Event Report

For Week Ending 02/25/00

The most recent spacecraft telemetry data was acquired from the Madrid
tracking station on Tuesday, 02/22. The Cassini spacecraft is in an
excellent state of health and is operating normally. On board activities
this week included Flight Software Partition Maintenance and SSR Pointer
Resets. The speed of the spacecraft can be viewed on the "Where is Cassini Now?" web page (

The Cassini and Galileo Programs participated in a joint conjunction
observation of Jupiter. Cassini's Radio and Plasma Wave Science Subsystem
(RPWS) and Galileo's Plasma Wave Subsystem (PWS) took measurements to
determine beaming characteristics of Jovian radio emissions. The
observation is significant due to the alignment of the two instruments.
There are only a few times in the lifetime of these missions when the
angular separation between Cassini and Galileo is about 5 degrees. This
condition is a requirement in order to be able to correlate the data
acquired during the observation. The other opportunity for such an
observation is in May of this year.

The Cruise 20 Sequence development kick-off meeting was held this week.
This marks the beginning of a 10 week development process concluding in
May. C20 is the first sequence for Instrument Checkout 2.

The Cassini Mission Planning Team released the Orbiter Cruise Activity
Handbook (OCAH) update. This update reflects activities during the
Instrument Checkout 2 (ICO-2) period describing each activity in detail.
The OCAH is used as a guide by the Sequence Team as part of spacecraft
command file generation.

The Software Requirements and Certification Review for the AACS flight
software (Version A7.7.6-32) was held on Friday, February 18. This is the
final review which certifies the software as ready for operational use. The
software will uplinked to the Cassini spacecraft on March 6.

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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