Cassini Weekly Significant Events for 01/31/02 – 02/06/02

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, February 6. The Cassini spacecraft is in
an excellent state of health and is operating normally. “Present
Position” web page, http://www.jpl.nasa.gov/cassini/english/where/ .

The C30 sequence continues to execute as planned. Science activities
include commanding for the Magnetometer Subsystem (MAG) to set the
Vector Helium Magnetometers bit to OFF state, and the conclusion of the
Imaging Science Subsystem (ISS) decontamination and Visual and Infrared
Mapping Spectrometer
Image/Occultation mini-sequences.

Preliminary results from the ISS decontamination mini-sequence show a
significant improvement for the Narrow Angle Camera. The C30
decontamination cycle lasted approximately 7 1/2 days and reached about
+4 degrees C. This was several degrees above the C28 cycle as the
replacement heaters were also powered
on. Final results should be available next week and will be followed by
discussions of further decontamination
activities.

Other spacecraft activities included clearing of the AACS high water
marks, an autonomous Command & Data Subsystem Solid State Recorder
Memory Load Partition repair, and an attitude control reaction wheel
friction test. Results from the test were normal.

The C31 preliminary Sequence Integration & Validation (SI&V) products
were released this week. Members of the Sequence Team reviewed the
package and submitted desired Sequence Change Requests (SCR). The SCRs
will be dispositioned in the C31 SI&V SCR approval meeting to be held
next week.

Science Planning (SP) reported the publication of a final report for the
Satellite Orbiter Science Team (SOST) Science Uplink Verification (SUPV)
activity. SP activities included a full set of TWT meetings to continue
the
integration of the orbits associated with the next delivery milestone,
which includes orbits 10 through 15, and a Titan Orbiter Science Team
(TOST) meeting to refine the integration details associated with the
recent T6/T7 trade.

The Spacecraft Office reported the Attitude Control flight software team
delivered version 8.5.0. This is the first version containing the energy
cutoff algorithm for the Saturn orbit insertion burn and will be used
for system mode testing. In addition, the Attitude Control ground
software developers delivered the preliminary set of target options to
Spacecraft Operations and Uplink Operations for early test and
evaluation. These comprise the full set of options for the Mission
Sequence System D8 delivery.

The Cassini Program conducted a NASA Quarterly Review on Monday,
February 4.

UVIS 1.3.0 instrument flight software was delivered to the Program
Software Library. Significant progress has been made in the Risk
Management area, following a Program wide review of the Significant Risk
List. The overall risk posture of the Program has been reduced due to
effective mitigation efforts. Redundancy in several risk statements has
been eliminated to create a crisp list for Risk Management during
Mission Operations.

A review and redesign of the proposed Telemetry Delivery System
architecture for tour support has been implemented due to changing
storage system costs, and lack of adequate existing expertise with
complex storage array systems.

The Cassini-Huygens outreach and education website, currently hosted at:
http://www.jpl.nasa.gov/cassini, has been relocated to a new, enhanced
environment. In conjunction with the move a new domain name has been
established for the Cassini-Huygens site. The new address is
http://saturn.jpl.nasa.gov. This change will take effect on February 5,
2002.