Cassini Significant Event Report
For Week Ending 06/23/00

The most recent spacecraft telemetry was acquired from the Madrid tracking station on Wednesday, 06/21. The Cassini spacecraft is in an excellent state of health and is operating as expected. The speed of the spacecraft can be viewed on the "Where is Cassini Now?" web page.

Maintenance of the Visual and Infrared Mapping Spectrometer (VIMS) instrument was accomplished by turning on the Infrared Optics decontamination heaters for a 24 hour period following Trajectory Correction Maneuver-14. Updated flight software and Instrument Expanded Blocks (IEBs) for the Cassini Plasma Spectrometer (CAPS) and VIMS instruments were loaded on board. CAPS actuator and flight software checkouts were performed. VIMS dark frame collection, internal calibration, and flight software checkout were begun. The Attitude and Articulation Control Subsystem (AACS) completed a reaction wheel unload.

Development for the Cruise 21 background sequence continues, C21 is currently in the Sequence Integration and Validation (SI&V) phase.

A review of the Tour Phase requirements and design of the Spacecraft Office was conducted. Feedback from the review board was positive. This is the first of a series of requirements and design reviews at the Office and Team level to be conducted through September.

Mission Planning has begun the formal coordination of engineering and science activities in the Saturn Orbit Insertion (SOI) and Probe Relay critical sequences.

An Orbiter Science Operations Working Team (OSOWT) telecon was held to continue the science integration process for the Jupiter Subphase. This telecon finalized the resolution of conflicts that existed in Phase F (Jupiter closest approach +15d to JCA +72d), and began the science integration process for the C25 portion of the Jupiter Subphase (JCA +72 days to JCA +120 days).

Version D7.2 of the Mission Sequence System (MSS) software was approved for delivery to operations. Installation has begun and will completed by the end of the week. Major changes in this delivery include updates to the Pointing Design Tool, engineering and science sequence modules, the MSS Tool Launcher, and a number of flight rules.

The Cassini web site has been added to the space link directory on the Universe Today web site. Universe Today provides space exploration and astronomy news in an overview format with links to sites where more detail may be found. The goal of this site is to build a comprehensive directory of space links for educators, students, and space buffs. The Cassini link may be found by going to http://www.universetoday.com and clicking on "Space Links." After selecting "Missions", the Cassini Home Page can be selected from the alphabetical listing.

Representatives from the web site eHobbies.com videotaped presentations made by Cassini Radio Science team members. The URL is http://www.eHobbies.com/tv_default.asp .

Additional information about Cassini-Huygens is online at http://saturn.jpl.nasa.gov.

Cassini will begin orbiting Saturn on July 1, 2004, and release its piggybacked Huygens probe about six months later for descent through the thick atmosphere of the moon Titan. Cassini-Huygens is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Office of Space Science, Washington, D.C.

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