Cassini Significant Events 09/28/06 - 10/04/06

October 6, 2006

(Source: Cassini Project)

The most recent spacecraft telemetry was acquired on Wednesday, Oct. 4, from the Canberra tracking complex. The Cassini spacecraft is in an excellent state of health and all subsystems are operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" page at .

Thursday, Sept. 28 (DOY 271):

The Huygens descent movies are now available in a multilingual version thanks to a collaborative effort between Europlanet and the European Space Agency (ESA) Communications office. Currently the CDROM contains six languages: English, French, German, Greek, Polish, Finnish. Other languages are being added and are downloaded from a web server when the CDROM is started on a computer connected to the Internet. For more information go to the ESA website.

The S24 sequence leads met to discuss implementation of a double playback of RADAR data from the Titan 19 encounter. The flyby will occur on Oct. 9 with playback scheduled for Oct. 10. The files have been built to support this request, and will be uplinked to the spacecraft on Oct. 3.

The first two flight software files for the Ion and Neutral Mass Spectrometer (INMS) were uplinked as scheduled to the spacecraft today, but due to the accidental severing of the fiber optic line between JPL and Goldstone, the remainder had to wait for the backup window on Friday. The procedure has been successfully completed and all files are currently onboard.

Friday, Sept. 29 (DOY 272):

The Aftermarket Process for the S29 sequence covering orbits 42 through 44 began today. This 5-week process will address proposed changes that require re-integration of the segments contained in the S29 sequence.

The input files for the official port for S27 were delivered today as part of the Science Operations Plan Update Process. The process concludes next week and the final development process for this sequence will begin on Oct. 16.

Saturday, Sept. 30 (DOY 273):

A new Cassini photo release is available on the public website. It showcases close-ups of the Saturn moon Helene. Cassini passed within 50,000 kilometers of Helene when these images were acquired. For more information link to:

Saturn Observation Campaign (SOC) members presented a two-year anniversary talk at the 21st annual Whirlpool Star Party in Birr, Ireland. Over 150 amateur astronomers, representing 18 amateur astronomy clubs throughout Ireland attended. Three Irish SOC members were in attendance, and several individuals expressed interest in joining the Saturn Observation Campaign. Cassini outreach material was distributed to all.

Sunday, Oct. 1 (DOY 274):

Orbit Trim Maneuver (OTM) #75 was uplinked to the spacecraft on Saturday and executed on Sunday. This is the apoapsis maneuver setting up for the Titan 19 encounter on Oct. 9. The main engine burn began at 3:29 AM PDT. Telemetry immediately after the maneuver showed the burn duration was 40.25 seconds, imparting a delta-V of approximately 6.46m/s, as planned. All subsystems reported nominal performance after the maneuver.

Monday, Oct. 2 (DOY 275):

The S25 sequence lead reported that the STEREO launch has been confirmed for Oct. 25. That is just three days after the start of execution for the S25 background sequence and will directly and indirectly impact DSN support for Cassini. Team members are working closely with the DSN scheduler and representatives from STEREO to reduce the impact as much as possible. The DSN passes requested for the entire sequence have been reviewed by the Navigation, Spacecraft, and Science Planning teams in order to assess the relative importance of each pass. S25 begins executing on Sunday, Oct. 22.

Tuesday, Oct. 3 (DOY 276):

The Solid State Power Switch (SSPS) on the SRU-A decontamination heater unexpectedly changed state from OFF to tripped at 276T16:27:02 SCET, Oct. 3, 2006, causing the SSPS trip count to be increased by 1. This event had no effect on spacecraft operations, as this heater is normally unpowered. This was one of the SSPS monitored by the on-board CDS autonomous fault protection algorithm, so was set back from tripped to OFF without ground intervention. The CDS table entry will be cleared and a memory readout will be performed in the next reporting period. This is now the 19th such trip and the fifth this year. These trips, attributed to Galactic Cosmic Rays, are expected to occur at a rate of about two per year since launch about nine years ago.

Wednesday, Oct. 4 (DOY 277):

The Encounter Strategy Meeting for T19 - T20 was held today. This meeting covered the period from Oct. 9 through Oct. 25, Titan encounters 19 and 20, and Orbit Trim Maneuvers 77, 78 and 79.