Cassini Significant Events for 03/10/05 - 03/16/05 The most recent spacecraft telemetry was acquired today from the Goldstone tracking station. 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 . Activities this week: Science this week included a magnetospheric boundary campaign performed by the Magnetospheric and Plasma Science (MAPS) instruments, and both individual and joint observations performed by the Optical Remote Sensing (ORS) instruments. Individual ORS observations included Far-IR Maps of Saturn taken by the Composite InfraRed Spectrometer (CIRS), Visual and Infrared Mapping Spectrometer (VIMS) observations of the E ring, Ultraviolet Imaging Spectrograph (UVIS) mosaics of Saturn's inner magnetosphere, and Imaging Science Subsystem (ISS) observations of Iapetus limb topography and geodesy. VIMS, CIRS and ISS jointly performed radial scans of Saturn's rings as Cassini crossed the ring plane on March 12, and ISS and UVIS periodically performed joint observations of Dione, Enceladus, Mimas, Rhea and Tethys. Thursday, March 10: Uplink Operations sent commands to the spacecraft today for an ISS Wide Angle Camera memory readout and reload of Instrument Expanded Blocks, power-off of the backup sun sensor assembly, and a Magnetospheric Imaging Instrument (MIMI) Low Energy Magnetospheric Measurement Subsystem (LEMMS) power cycle, sensor reset, and diagnostic mini-sequence. The Spacecraft Operations Office performed a reaction wheel momentum adjustment. Navigation delivered the final orbit determination solution for Orbit Trim Maneuver (OTM) 17. The actual maneuver will take place tomorrow evening. Instrument Operations delivered ISS Flight Software Version 1.4 to the Project Software Library. A delivery review will be held on April 15, with uplink and in-flight test to occur in June. The Cassini Imaging Team's (ISS) first scientific findings on Saturn's largest moon, Titan, are being published today in the journal Nature. Friday, March 11: OTM-17 was completed on the spacecraft this evening. This maneuver, also known as the "E1 + 3 days maneuver", is part of the E1-T7 10-maneuver optimization chain. The main engine burn began at 8:31 p.m. PST. A "quick look" immediately after the maneuver showed the burn duration was 2.822 sec long, giving a delta-V of 0.42 m/s. ACS reported the burn termination was a "nominal complete" with an accelerometer cutoff. Propulsion indicated the burn was nominal. Tank pressures, temperatures, etc, were nominal. This maneuver was performed in the "blow-down" mode, where the fuel and oxidizer tanks were not directly connected to the helium pressurant source. Thermal reported all nominal with temperatures recovering as expected. Power margin throughout the maneuver was nominal. There was no unexpected CDS or Fault Protection activity. Monday, March 14: Uplink Operations sent real-time commands to the spacecraft for a CDS memory readout, to perform Cassini Plasma Spectrometer (CAPS) actuator diagnostics, reset the MIMI LEMMS Sensor, and perform an INMS flight software normalization procedure. Tuesday, March 15: Mission Assurance and Huygens Probe Operations presented a paper entitled "Collaborative Risk Management for the Cassini-Huygens Probe Mission" at last week's IEEE Aerospace Conference. The paper described the collaborative effort of risk management and risk mitigation employed by the project. The talk was well received at the conference and it is hoped that the approach implemented by the Cassini-Huygens team will serve as an example for others who are implementing risk management during critical phases of mission operations. Cassini Outreach and Saturn Observation Campaign members participated in Community Science Night at La Fetra Elementary School, a K-5 school with 720 students, in Glendora, CA. In addition to a school science fair, visitors passed by a NASA image display, with 3-D glasses and lithographs for all. They also enjoyed a petting zoo, and Saturn and moon observations under perfect skies. The event also included the "Egg Stronauts Egg Drop" from atop the tall ladder on a Los Angeles County Fire Truck, and featured the kindergarten astronomy class's scale model of the solar system. Over 300 visitors to the telescopes received Saturn trading cards and Cassini bookmarks. Cassini Outreach also participated in a science fair at Barnhart School in Arcadia, CA. Over 100 students in grades 1-6 submitted projects. The Los Angeles Astronomical Society hosted viewing of Saturn and other celestial bodies. All science fair participants received Cassini bookmarks. Wednesday March 16: An S12 Science Operations Plan Update wavier disposition meeting was held on Wednesday. Project Management approved the two waivers under consideration. In support of S10, SCO performed an Integrated Test Lab (ITL) test of the Titan-5 closest approach sequence for the April 16, 2005 encounter. The ITL has also been busy performing ACS Flight Software A8.7.2 updates planned for a late May 2005 uplink. This version will update maneuver telemetry scale factors to improve visibility during smaller main engine maneuvers. A8.7.2 will also update the guidance and control detumble vectors for more accurate control late in the mission. Wrap up: Check out the Cassini web site at http://saturn.jpl.nasa.gov for the latest press releases and images. Further updates to the education section and the K-4 program pages were posted live this week at http://saturn.jpl.nasa.gov/education/index.cfm 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. --- To unsubscribe from Cassini Spacecraft Updates, send a message to leave-cassini-xxxx@list.jpl.nasa.gov --- Visit the JPL Cassini home page for more information about the Cassini Project: <http://saturn.jpl.nasa.gov/>
