NASA Cassini Significant Events 11/9/11 – 11/15/11

The most recent spacecraft telemetry was acquired on November 15 from the Deep Space Network tracking complex at Canberra, Australia. The Cassini spacecraft is in an excellent state of health and with the exception of the CAPS instrument being powered off, 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/mission/presentposition/.

Wednesday, Nov. 9 (DOY 313) Science activities this week while the spacecraft was approaching apoapsis were dominated by Magnetospheric and Plasma Science (MAPS) investigations. The MAPS instruments acquired nearly continuous measurements of Saturn’s outer magnetosphere and magnetosheath. By doing this once every four to six months, the MAPS instruments are able to observe Saturn’s magnetosphere over a solar cycle, from one solar minimum to the next, and investigate magnetospheric periodicities and how the Saturn kilometric radiation (SKR) period is imposed on the magnetosphere.

Thursday, Nov. 10 (DOY 314) An article called “Saturn and the Solar Wind Send Tiny Particles Flying” was posted on the Cassini web site today. It describes how dust particles act in an unusual way around Saturn. Instead of being attracted to the giant planet as might be expected, dust particles are ejected away from Saturn in streams that move at speeds of more than 100 kilometers per second. Using data from the Cassini mission, a team of scientists has now successfully modeled these dust streams. For more information on this subject, link to: http://saturn.jpl.nasa.gov/news/cassiniscienceleague/science20111110/.

Today the Imaging Science Subsystem (ISS) narrow angle camera encountered a machine error and warm start during an idle period and recovered nominally, with no images lost. A new Incident Surprise Anomaly (ISA) report will be opened.

Friday, Nov. 11 (DOY 315) The S71 background sequence was signed off and approved on Tuesday, Nov. 8, in preparation for uplink scheduled for today via the Autorad tool. Sunday, Nov. 13 (DOY 317) The Navigation Team is preparing for Orbit Trim maneuver 300 (OTM-300), which is scheduled to execute Wed., Nov. 23. It sets up the trajectory for the dual Dione/Titan flybys. Because this maneuver has a relatively large deterministic delta-V cost (3 m/s) and is executed only 45 minutes from periapsis, delaying to the backup maneuver location would be very costly in terms of delta-V. Due to this sensitivity, the maneuver will be designed early enough to enable six uplink opportunities, thereby eliminating the possibility of a delay to the backup time due to DSN transmitter failure.

Monday, Nov. 14 (DOY 318) Port 1 products were due today as part of the S73 Sequence Implementation Process (SIP). The products will be merged and sent out to the flight team for review. Redelivery was requested of two teams to correct pointing designs that stepped outside of their allocated time window.

Tuesday, Nov. 15 (DOY 319) In support of S74, the Science Planning and Sequencing (SPST) Team continued work on shifting the sequence boundary between S74 and S75 by approximately 8 hrs to fall after Cassini’s Goldstone 70 meter pass on DOY 238 instead of the Madrid 70m pass on DOY 237, to avoid a 70m conflict with the Mars Science Laboratory (MSL) Project during their 30-day-post-Entry-Descent-Landing conditioning phase. This occurs within a Saturn Target Working Team (TWT) segment which spans across the S74-S75 sequence boundary.