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The most recent spacecraft telemetry was acquired on Mar. 29 from the Deep Space Network tracking complex at Canberra, Australia. 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/mission/presentposition/.
Wednesday, March 23 (DOY 082)
The Downlink Ground System (DGS) team continued coordination of the Java Distributed Object Manager (DOM) end-to-end testing on the Network File System (NFS). The two outstanding major Java DOM issues have been resolved, allowing Cassini teams to support end-to-end testing of the Java NFS DOM this week.
The Instrument Operations team, working with the DGS team, successfully exercised tests applying Multicast and Telemetry Delivery System (TDS) processes with the Multi-Mission Image Processing Laboratory (MIPL). Multicast is expected to become operational for Cassini in the June/July timeframe.
Thursday, March 24 (DOY 083)
In science this week, the focus of the observations continued from last week with the Magnetospheric and Plasma Science (MAPS) instruments making near-equatorial observations of the magnetosphere as Cassini approached apoapsis. This MAPS campaign provides an opportunity to acquire nearly complete and 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 at different points over a solar cycle, investigate magnetospheric periodicities, and study how the Saturn kilometric radiation period is imposed on the magnetosphere. On the final day of the week, Cassini turned to Titan, providing the remote sensing instruments a distant view of the large moon to make cloud and surface monitoring measurements.
Friday, March 25 (DOY 084)
On Wednesday it was noted that the Cosmic Dust Analyzer (CDA) had not written science packets since 2011-079T20:51 SCET. As a result, the science packet error counter (Telemetry Channel: C-2238) count increased to approximately 200,000 counts. The instrument was otherwise performing normally. Housekeeping data continued being produced; all commanding was accepted and executed as expected. The overall particle detection trigger rate seemed to be in a medium load range and far from saturation. Why the instrument stopped producing science data packets remains unclear. The instrument was still able to trigger, process data, and classify events. This incident is currently under investigation. A reset/reload real time activity fixed this problem today and CDA science packet generation is now back to normal.
Saturday, March 26 (DOY 085)
As part of NASA’s collaboration with DonorsChoose.org, an online charity that makes it easy to help students in need through school donations, 96 teachers with 6,533 students from schools in high-poverty communities in 38 states across the country have received Cassini outreach materials. Over 30 other teachers have since expressed an interest in receiving NASA materials for their classrooms, and these requests will be filled next week.
Sunday, March 27 (DOY 086)
Cassini's Twitter network welcomed its 100,000th follower over the weekend. For real-time Cassini news in a micro-blog format, visit http://twitter.com/CassiniSaturn.
The annual back-up gyro calibration occurred over the weekend.
Monday, March 28 (DOY 087)
Target Working Team and Orbiter Science Team integrated products for the S70 sequence, covering orbits 153 through 157 in September through November 2011, were delivered last week. The integrated products are in their final form and no re-integration is planned. The Sequence Implementation Process will kick off on April 14. The instrument teams are currently working on the pointing designs for this sequence.
Tuesday, March 29 (DOY 088)
This past week’s tracking of Reaction Wheel Assembly #3 (RWA-3) performance in S67 indicated RWA-3 is looking very good and is functioning normally. The wheel performance continues to be closely monitored.
The most recent Cassini-Huygens Analysis and Results of the Mission (CHARM) teleconference was held today. The topic: "Exploring Titan in 3D with Cassini RADAR - Including Evidence for (and Against) Ice Volcanism" presented by a member of the Cassini RADAR Team. A PDF of the presentation package may be obtained at: http://saturn.jpl.nasa.gov/video/products/MultimediaProductsCharm/. An audio recording of the presentation was made and will be linked to the same location within a few days.