Cassini Update - September 5, 2003

Cassini Significant Events
for 08/28/03 - 09/03/03

The most recent spacecraft telemetry was acquired from the Madrid
tracking station on Wednesday, September 3. The Cassini spacecraft is in
an excellent state of health and is operating normally. Information on
the present position and speed of the Cassini spacecraft may be found
on the "Present Position" web page located at
http://saturn.jpl.nasa.gov/operation...t-position.cfm .

On-board activities this week included clearing of the attitude control
high water marks, Radio and Plasma Wave Science (RPWS) High Frequency
Receiver calibrations and high rate observations, and uplink of an
Imaging Science Subsystem memory load. Members of the Huygens team
reported successful results from last week's probe mute test. With the
participating orbiter instruments muted, all commands sent from the
orbiter to the probe were successfully registered.

Cassini and Huygens have officially released the 56 kilobit per second
(kbps) NASA Integrated Service Network (NISN) data line between JPL and
the European Space Operations Center (ESOC). In its place, the projects
will use a 384 kbps NISN data line that is shared with the Integral
project. This will have a large potential benefit for both the probe and
orbiter missions. During a demonstration of the transfer of the probe
data during the Command and Data System Version 9 flight software
checkout last spring, the 56 kbps line backed up significantly. Testing
during August on the new line has shown data rates of between 210 kbps
and 300 kbps allowing data transfer several times faster than before.
This will allow ESOC more rapid access to the probe data and will allow
for the earlier release of the on-board recorders for further data
collection after the probe mission.

A delivery coordination meeting was held for the Maneuver Automation
System version 3.0. New functionality for the software includes and
enhanced user interface to simplify parameter inputs and view outputs;
an interface to the reaction wheel bias tool; "one button" architecture
to bind together Navigation and Spacecraft Operations Office processes
into a seamless process. This system will be first used in operations
for Trajectory Correction Maneuver 19a, which will execute next week.

The JPL Navigation Section held a one day review of the Cassini
Navigation Team's preparations for Saturn approach and orbital
operations. The review went well. While the board generated a small
number of follow on actions for the team, the consensus was that the
team was in good shape and well prepared for Saturn operations. A
separate review concentrating exclusively on the Huygens probe mission
will be held later.

The application window for new members to the Saturn Observation
Campaign (SOC) is now officially closed for 2003. As of August 30,
there were 235 participants. 135 are new, 150 reside in the USA, and 85
reside in foreign nations. For the 2003-2004 year, SOC members reside
in 34 US states, Puerto Rico, and 35 foreign countries.

A new lithograph illustrating Saturn Orbit Insertion with information on
the Cassini Mission and tour at Saturn has been produced. Copies are
available through the Cassini Outreach Office for talks and
Cassini-related events.

Cassini is a cooperative project of NASA, the European Space Agency and
the Italian Space Agency. The Jet Propulsion Laboratory, a division of
the California Institute of Technology in Pasadena, Calif., manages the
Cassini mission for NASA's Office of Space Science, Washington, D.C.

Cassini Outreach
Cassini Mission to Saturn and Titan
Jet Propulsion Laboratory
California Institute of Technology
National Aeronautics and Space Administration