Cassini Significant Event Report
For Week Ending 07/10/98
The most recent Spacecraft status is from the DSN tracking pass on Thursday, 07/09, over Canberra. The
Cassini spacecraft is in an excellent state of health and is executing the C8 sequence nominally. The C8
sequence will end this Sunday, 7/12, at which point the C9 sequence will begin. 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)
Inertial attitude control is being maintained using the spacecraft's hydrazine thrusters (RCS system). The
spacecraft continues to fly in a High Gain Antenna-to-Sun attitude. It will maintain the HGA-to-Sun attitude,
except for planned trajectory correction maneuvers, for the first 14 months of flight.
Communication with Earth during early cruise is via one of the spacecraft's two low-gain antennas; the antenna
selected depends on the relative geometry of the Sun, Earth and the spacecraft. The downlink telemetry rate is
presently 40 bps.
Spacecraft Activity Summary:
On Wednesday, 07/08, the Solid State Recorder (SSR) record and playback pointers were reset, according
to plan. This housekeeping activity, done approximately weekly, maximizes the amount of time that recorded
engineering data is available for playback to the ground should an anomaly occur on the spacecraft.
On Thursday, 07/09, the C9 sequence was uplinked to the spacecraft. The C9 Sequence will begin executing
on Sunday 07/12.
Activities scheduled for the week of 07/10 - 07/16 include: SSR Flight Software Partition Maintenance,
enable of data mode RTE_158, adjustment of Automatic Thermal Control-6, and zero-out of on-line CDS
Reset Counter (all on 07/11); SSR Pointer Reset, update of Accelerometer Scale Factor, and AACS Fault
Protection Log Maintenance (all on 07/15).
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.