Cassini Significant Event Report

For Week Ending 12/25/98

Due to the Christmas and New Years Holidays, reporting periods for the next
three weeks will be slightly irregular. This week's report covers Friday
(12/18) through Wednesday (12/23) (inclusive).

Spacecraft Status:

The most recent spacecraft status is from the DSN tracking pass on Tuesday,
12/22, over the Goldstone tracking station. The Cassini spacecraft is in
an excellent state of health and is executing the Cruise 11 sequence

Spacecraft Activity Summary:

On Friday, 12/18, two activities were performed. The third component of
Periodic Engineering Maintenance (Reaction Wheel Portion) executed, and
Instrument Flight Software was updated for MIMI, CDA, CIRS and RPWS in
preparation for Instrument Checkout.

On Monday, 12/21, two additional activities were done. Occurring
approximately every 6 months, Probe Checkout number 3 was conducted as
planned, and following this a Flight Software update was performed for CAPS
and INMS in preparation for Instrument Checkout.

Upcoming events:

Activities scheduled for the week of 12/24-12/29 (Thursday through
Tuesday) include reset of the PSA (Probe Support Avionics) Prime status
following Probe Checkout (PCO) on 12/24, beginning of Instrument Checkout
(ICO) Period, switch to High Gain Antenna (HGA), High Watermark Clear, and
playback of PCO data on 12/27, begin Radio Science Subsystem (RSS) ICO
activities and Ultra Stable Oscillator Test #1 on 12/28, and RSS Test B
and playback of ICO data on 12/29.

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.

Media Relations Office

Jet Propulsion Laboratory

California Institute of

National Aeronautics and Space

Pasadena, Calif. 91109.
Telephone (818) 354-5011