NASA Cassini Significant Events for 05/06/09 – 05/12/09

The most recent spacecraft telemetry was acquired on May 12 from the Deep Space Network tracking complex at Goldstone, California. 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: http://saturn.jpl.nasa.gov/operations/present-position.cfm.

Wednesday, May 6 (DOY 126):

The International Astronomical Union (IAU) Working Group for Planetary System Nomenclature has approved a new designation and name for a satellite of Saturn discovered by Cassini, cf. IAUC 8873: Saturn LIII Aegaeon = S/2008 S 1 IAUC 9023. Aegaeon is estimated to be half a kilometer in diameter, orbits within the bright segment of Saturn’s G ring, and is likely a major source of the ring. Debris knocked off the moon forms a bright arc near the inner edge, which in turn spreads to form the rest of the ring.

In Greek mythology, Aegaeon was one of the three Hecatonchires. Children of Gaia and Uranus – or the Earth and Sky – the name “Hecatonchires” derives from the Greek for “hundred” and “hand”, with each of the three having one hundred hands and fifty heads. They were giants of incredible strength and ferocity, even superior to that of the Titans, whom they helped overthrow, and the Cyclopes.

Thursday, May 7 (DOY 127):

Last week it was reported that the flight team had made the determination, and uplinked the necessary files, to increase the command loss timer (CLT) value on-board the spacecraft from the nominal 90 hours to six days. Now that DSS-14 is back up and running smoothly, commands have been sent to return the CLT to the nominal 90-hour value.

This evening, AACS powered on Sun Sensor Assembly B and performed a real-time checkout from telemetry data during the rolling downlink. Results of this annual checkout indicate that the sensor is performing normally.

Friday, May 8 (DOY 128):

An analysis of the current spacecraft trajectory has shown that the excellent delivery accuracy to the Titan 54 encounter has placed the spacecraft just about exactly on the planned post encounter trajectory. This coupled with the 2 m/s deterministic maneuver planned for next Thursday – Orbit Trim Maneuver (OTM) # 195 – resulted in a minimum delta-V solution that did not include OTM-194. The smooth Titan flyby also resulted in a converged orbit determination solution after only one tracking pass. As a result, OTM-194, scheduled for May 8, has been cancelled.

Monday, May 11 (DOY 131):

The Target Working Team (TWT)/Orbiter Science Team (OST) integrated products for S55 covering orbits 121 through 123 were delivered today. The integrated products are in their final form and no re-integration is planned. The next step in sequence development, Science Operations Plan (SOP) implementation, will kick off on May 27. Between now and then, the instrument teams will be working on pointing designs for the sequence. TWT/OST teams deliver integrated sequence products for the extended mission about every five weeks.

Tuesday, May 12 (DOY 132):

The final sequence development process for S52 began today. On Friday of last week, Science Planning handed off all input products from the Science Operations Plan process, and today the kickoff meeting for the Science and Sequence Update Process was held.

Development for the AACS Flight Software (FSW) update A8.7.7 concluded today when the software was reviewed and accepted at the Software Requirements and Certification Review. Uplink is scheduled to begin on May 26.

Visit the JPL Cassini home page for more information about the Cassini Project: http://saturn.jpl.nasa.gov/