Cassini Significant Events for 03/30/06 - 04/05/06 The most recent spacecraft telemetry was acquired Wednesday, April 5, from the Goldstone tracking stations. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/operations/present-position.cfm . Thursday, March 30 (DOY 089) A friction test was performed today on the prime reaction wheels (RWA) numbers one, two and four. This test is performed every three months to enable the project to track trends in the state of the wheels. In this test, the RWAs are spun up to 900 rpm in both directions and are timed as they run down to 0 rpm. The longer the run-down time, the better. The results for RWAs 1 and 4 were not a cause for alarm, but did indicate less than hoped for trends in friction levels. The results for RWA-2 were unchanged from previous tests. The Project will continue to monitor RWA performance closely. Commands for a Cosmic Dust Analyzer (CDA) decontamination activity were sent to the spacecraft today. The mini-sequence will execute on Sunday, April 2. An update to the Live Inertial Vector Propagator (IVP) Update products was generated by the S19 leads that includes an update to the Iapetus vector on DOY 097T19:38:10. No other changes were made to the products. Uplink is planned for Friday, March 31, with execution beginning on April 7. Friday, March 31 (DOY 090) A Software Requirements and Certification Review for ACS flight software patch A8.7.4 occurred today. This is the last review to be held for the A8.7.4 FSW patch uplink activity scheduled for April 10 - 13. The Magnetospheric Imaging Instrument (MIMI) team sent an automated sequence processor (ASP) real time command to turn the MIMI collimator on. ASP is used by the instrument teams to send commands that are specific to their instrument, and that will not affect other instruments or the spacecraft. The tool is valuable in that it reduces the workload of the sequence leads by not requiring their involvement in the generation of every instrument real time command. A Saturn Observation Campaign member visiting Texas presented an afternoon demonstration of hands-on activities from Cassini's K-4 Reading, Writing and Rings and 5-8 Saturn in your Kitchen programs to the directors of the two Houston Museum of Natural Sciences' Challenger Centers and the Museum's George Observatory. The demonstration took place at the Observatory located an hour south of Houston in Brazos Bend State Park. Both of these programs have activities that work well in museum and after school program settings. These materials are available on the Cassini Education page http://saturn.jpl.nasa.gov/education/index.cfm. Monday, April 3 (DOY 093): The story of possible liquid water on Enceladus was the top story on Space.com today. Release of Ring World 2 DVD: Ring World 2 includes a Spanish language version, English language and closed captioning all on one DVD. Copies have been shipped out to members of the International Planetarium Society, the Navigator Program's Night Sky Network, NASA Solar System Ambassadors, Space Place's museum network, the USGS and throughout the Cassini mission since many Cassini members do school and public talks. In addition, an RW2 version for video Ipod is now available. Tuesday, April 4 (DOY 094): Science activities this week included the continuation of the magnetotail campaign by the Magnetospheric and Plasma Science (MAPS) suite of instruments, the Ion and Neutral Mass Spectrometer scan for dense particle regions far from Saturn, CDA with the search for Saturnian dust stream particles, and ISS with an icy satellite spectrophotometry campaign. The Composite Infrared Spectrometer team acquired their first higher latitude high spectral resolution composition measurements of Saturn at 45N latitude. Wednesday, April 5 (DOY 095): Orbit Trim Maneuver (OTM) #57 will execute late this evening with a scheduled burn time of 9:40pm Pacific Time. Details of this event will be published in the Significant Events Report next week. OTM-57, an apoapsis maneuver, is a main engine burn with a commanded delta-V of 0.37 m/sec A delivery coordination meeting was held today for the confirmation of the Spacecraft Operations Office updated Command Data Base. CDB version 12b will be used with the Mission Sequence Subsystem D12 software to be delivered in May. Wrap up: Check out the Cassini web site at http://saturn.jpl.nasa.gov for the latest press releases and images. Upcoming Outreach Events: A Virginia Saturn Observation Campaign Member will present "Cassini/Huygens Mission: results to date" at The Virginia Living Museum in Newport News, VA, April 6, 2006. The talk is part of the museum's Wild and Starry Night series. Ring World will also be playing in the Planetarium that evening. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. JPL designed, developed and assembled the Cassini orbiter.
