21 Sep 2001
(Source: Jet Propulsion Laboratory)
Cassini Weekly Significant Events for 09/13/01 - 09/19/01
The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, September 19. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the spacecraft's position and speed can be viewed on the "Present Position" web page, http://www.jpl.nasa.gov/cassini/english/where/.
Recent instrument activities include the conclusion of a detailed solar wind study by the Cassini Plasma Spectrometer, two Radio and Plasma Wave Science High Frequency Receiver calibrations, a Cosmic Dust Analyzer (CDA) decontamination activity, and the first part of a CDA noise evaluation study. Engineering activities taking place onboard the spacecraft this week include a calibration of the Stellar Reference Unit and a periodic engineering maintenance activity that exercised both the Engine Gimbal Actuator and backup Reaction Wheel Assembly. Real-time commands were uplinked to the spacecraft to clear the Attitude Control Subsystem (ACS) high-water marks.
A Command Approval Meeting was held to seek approval for uplink of the Visual and Infrared Mapping Spectrometer (VIMS) Flight Software (FSW) version 4.2 to the Solid State Recorder and to load it into the instrument. The FSW was successfully uplinked and loaded on September 20.
The C29 Sequence Team process began this week with delivery of the first stripped subsequence Spacecraft Activity Sequence Files (SASFs) and integrated sequence files. The kickoff meeting was held, and each team is currently in the process of completing and reviewing their detailed subsequence SASFs. C29 will feature the first use of "cyclics", which use a call from the background sequence to run an external program multiple times, conserving sequence space by not having to expand the program for each occurrence. This capability will be essential for the tour.
The C30 Science Planning Team development process began this week and is preparing for the Program briefing next week.
An all-day Titan Orbiter Science Team (TOST) meeting was held this week. The TOST started integrating the plans for Titan encounters T11 through T22 outside of the +/- 30-minute period around Titan closest approach. The period within +/-30 minutes for all the remaining Titan flybys was also worked.
The Imaging Science Subsystem (ISS) team completed the initial implementation of ISS FSW upgrades. The first basic tests have begun on Electronic Ground Support Equipment, and a full Acceptance Test Plan is being prepared.
Developers for the Mission Sequence Subsystem (MSS) ground software package have drafted a final plan for basic MSS D8.0 infrastructure, including support for the UNIX Sun Solaris 2.7 operating system and a new command database that includes Command & Data Subsystem version 9 and ACS version 8 FSW.
Outreach is taking delivery of its new educational poster, "Cassini Unveils the Myth" this week. The front of the poster features a mural painted by middle school artists showing Kronos unveiling Saturn, while the back provides classroom lessons for teachers. The poster will be available by request to the Cassini Program and from the nationwide Educator Resource Center Network and NASA CORE.
Cassini 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, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.
Cassini Mission to Saturn and Titan
Jet Propulsion Laboratory
California Institute of Technology
National Aeronautics and Space Administration