Significant Event Report for Week Ending 3/12/1999

Cassini Significant Event Report

For Week Ending 03/12/99

Spacecraft Status:

The most recent spacecraft status is from the DSN tracking pass on
Thursday, 03/11, over the Canberra tracking station. 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 (http://saturn.jpl.nasa.gov/operations/present-position.cfm)

Spacecraft Activity Summary:

On Saturday, 03/06, the spacecraft switched from low gain antenna 1 to low
gain antenna 2 as the prime communications path due to changing geometry
as the spacecraft gets closer to the sun.

On Tuesday, 03/09, all three portions of Periodic Engineering Maintenance
were performed: Reaction Wheel Assembly (RWA) exercise, BAIL (a test for
bit errors in some backup memory) and Engine Gimbal Actuator (EGA)
exercise. Following this a High Water Mark Clear was performed, and the
Solid State Recorder (SSR-B) record and playback pointers were reset.

On Thursday, 03/11, the Cruise 12 sequence deregistered as planned and the
Cruise 13 sequence was uplinked to the spacecraft.

Upcoming events:

Activities scheduled for the week of 03/12-03/18 include activation of the
Cruise 13 sequence on 03/14, update of the AACS Constraint Monitor and
Flight Software Partition Maintenance on 03/15, and an SSR Pointer Reset
on 03/16.

Additional information about Cassini-Huygens is online at http://saturn.jpl.nasa.gov.

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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