Cassini Significant Events for 05/02/02 – 05/08/02
The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, May 8. 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/cassini/english/where/ .
Spacecraft activities included loading of the new data policing tables,
and uplink of the AACS Clear High Water Marks in preparation for a
Reaction Wheel Assembly transition.
Instrument activities this week included the loading of several
Instrument Expanded Blocks, execution of Periodic Instrument Maintenance
for RADAR and the Radio Science Subsystem (RSS), observations of
Fomalhaut were taken by the Visual and Infrared Mapping Spectrometer and
Ultraviolet Imaging Spectrograph subsystems, and the Imaging Science
Subsystem commanded the Narrow Angle Camera heaters to OFF after two
months of decontamination.
RSS personnel successfully conducted a pattern calibration using
Ka-band, X- and, and S-band frequencies over DSS-25. Data from all
pattern calibrations conducted during Cruise will be compiled into a
single model of the high-gain antenna. The Radio Science Team will use
this model to analyze ring data acquired during Tour. During the pattern
calibration, the status of the Ka-band Translator (KaT) was monitored.
It was noted that the KaT remained in its “good state” throughout the
track. The last time that the S-band Transmitter and KaT were both
powered ON, the KaT immediately snapped to its “bad state”.
RSS personnel also conducted a test of the Ka-band uplink subsystem, the
monopulse tracking subsystem, and a new uplink acquisition template.
This is the first use of these subsystems since January 4 at the end of
Gravity Wave Experiment (GWE) #1, and the first use ever of the new
template. Additionally, the monopulse developers successfully performed
an on-point-phase-calibration.
The Program participated in a NASA Quarterly Meeting and a two day
Independent Review Team Meeting.
At the Instrument Operations Working Group, a presentation was given
about technical options that will satisfy voice communication
requirements between Distributed Operations Sites and JPL during
operations, given anticipated budgetary constraints in future years. A
Peer Review of Cassini’s Verification & Validation (V&V) plans was held
with 314 section personnel in attendance. Also attending were V&V
engineers from the Mars Exploration Rovers and Space Infrared Telescope
Facility projects. Feedback from this meeting has been integrated into
the Cassini V&V plan and Critical Design Review package.
Delivery Meetings were held for Telemetry, Command & Data Management
26.4 for Telemetry, Command, and Distributed Object Manager, and for
Mission Sequence Subsystem D8. This week Cassini’s Educational Outreach
staff is attending the 40th Anniversary of Space Flight at the
Smithsonian Institution.
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.
