Status Report

Cassini Weekly Significant Events for 07/27/00 – 08/02/00

By SpaceRef Editor
August 4, 2000
Filed under

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Tuesday, 08/01. The Cassini spacecraft is in an excellent state of health and is operating normally.  The speed
of the spacecraft can be viewed on the "Where is Cassini Now?" web page ( "http://www.jpl.nasa.gov/cassini/today/" )
 
The final activity for C21 was Probe Checkout #6.  Preliminary results indicate the checkout went as expected with no data outages reported. This activity represents the first time Cassini has used Deep Space Station (DSS) 14 for operational support since X-Band uplink became available.
 
During the checkout, Instrument Operations (IO) and Mission Support and Services Office (MSSO) personnel performed a test of the Virtual Private Network (VPN) tunnel over the Internet using live spacecraft telemetry. The test used the same procedures that are used in actual operations, including the Science Operations and Planning Computer (SOPC) data grab script, to transfer the telemetry from JPL to the Radio and Plasma Wave Science Subsystem site (RPWS) at University of Iowa.
 
After Probe Checkout, C21 deregistered on board the spacecraft.  For the remainder of the C21 time period until C22 registers in September, all regularly scheduled maintenance activities will be conducted via real time commands.
 
This week the Spacecraft Operations team began a four-week task of switching to a new version of Command & Data Subsystem Flight Software (CDS FSW), Version 7.0_011.
 
The software was uplinked to the spacecraft and stored in the Solid State Recorder-B (SSR-B). Next, new flight software called Emergency RAM load (ERAM) was uplinked to the spacecraft.  This uplink involved over 100 files with the retransmission of only one file required.  The ERAM load is intended to replace Programmable Read-Only Memory (PROM) as a quicker and more efficient means of loading CDS Flight Software from the ground. SSR-A was then turned on.
 
ERAM was used to facilitate "cold-booting" the back-up, or on-line, CDS to Version 7.0_011 from SSR-B.  Finally, additional real time commands were sent and SSR-A was "embraced" by the on-line CDS and partitioned properly. Version 7.0_011 is operating nominally in the on-line state and its activation as Prime remains on schedule for August 9th.
 
The preliminary Sequence Change Request (SCR) Approval Meeting was held for the Cruise 22 sequence.
 
C23 has passed its third and final input port as part of Science Planning Virtual Team (SPVT) development.  SPVT activities for C23 will conclude August 14.
 
Representatives from the Uplink Operations Team (ULO) and System Engineering (SE) traveled to the Southwest Research Institute (SWRI) to participate in a two-day review of the Cassini Information Management System (CIMS).  Special emphasis was directed toward the physical database table design, data field security, and how user authentication will be integrated into the overall Cassini GDS design.
 
A Software Review Certification Requirements meeting (SRCR) was held for Cassini Plasma Spectrometer (CAPS) FSW.  This delivery contains a patch to correct the unexpected noise counts found in data during low voltage operations and CAPS Data Processing Unit (DPU) reset.
 
System Engineering has produced a Jupiter Integrated Schedule covering activities for both operations and development.  This schedule is being used as a tool to maintain Flight Team preparedness to support Jupiter events for sequences C22 through C25.
 
Cassini Outreach participated in the training sessions for Solar System Educators, commencing this week and continuing through Saturday.  Solar System Educators are master teachers who will return to their communities and train other teachers in the use of educational materials developed by solar system exploration missions.
 
Cassini Outreach
Cassini Mission to Saturn and Titan
Jet Propulsion Laboratory
California Institute of Technology
National Aeronautics and Space Administration

SpaceRef staff editor.