Status Report

NASA Cassini Significant Events for 07/17/03 – 07/23/03

By SpaceRef Editor
July 28, 2003
Filed under , ,
NASA Cassini Significant Events for 07/17/03 – 07/23/03

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, July 23. 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 .

On-board activities this week included Radio and Plasma Wave Science
(RPWS) High Frequency Receiver (HFR) calibrations, Cosmic Dust Analyzer
decontamination and Instrument Expanded Block (IEB) load execution,
Visual and Infrared Mapping Spectrometer (VIMS) functional test and deep
space characterization, and Saturn Orbit Insertion (SOI) demo sequence
uplink to RAM. Memory read outs have verified that the sequence was
successfully loaded into RAM, and is registered but not active in both
the prime and online strings.

On July 18, a real-time command moratorium was initiated to support the
SOI sequence demonstration. It will be in effect until August 5.
Commanding is planned during this time frame. At the end of each
commanding period, a new command loss timer (CLT) value will be
uplinked. This will simulate the SOI situation where deliberate
management of the CLT hedges against a hardware command decoder failure.

Mission Support and Services Office personnel conducted an Emergency
Control Center (ECC) demonstration at the DSS complex at Goldstone,
California. The demo confirmed the capability to flow telemetry, and to
issue commands from the ECC.

The C39 Final Sequence Integration and Validation (FSIV) sequence
generator, sequence translator, and sequence of events generation
products corresponding to the merged files have been released for review
by the Spacecraft Operations Office (SCO) and instrument teams. These
products include the Sequence Change Requests (SCR) approved at the July
11 SCR approval meeting, as well as some instrument internal changes
which did not require change documentation.

S07/S08 Science Operations Plan implementation process completed this
week, with a final wrap-up meeting scheduled for next week.

A waiver disposition meeting was held this week as part of the S14
Science and Sequence Update Process (SSUP) Verification and Validation
(V&V) activity. In addition, Preliminary Sequence Integration and
Validation 2 (PSIV) SCRs and comments were delivered, the sequence lead
delivered a merged background sequence containing Inertial Vector
Propagator/Star ID commands, updated PSIV2 IEB loads were delivered,
then processed by the command data subsystem and sequence leads for a
final release. The FSIV SCR approval meeting will be held next week
along with the FSIV sequence approval meeting.

Solar Conjunction Experiment #2 ended last Tuesday with the Ka-band
Translator (KaT) frequency still in its bad region. As a result, the
Project has approved an additional period for continuing recovery
attempts for the KaT. One condition is that real-time commands may not
be used due to the current command moratorium. The suite of Ka-band
equipment was powered back on and Radio Science Subsystem (RSS)
personnel developed a strategy to use the additional passes at DSS-25
from now till August 2.

The Cassini Archive Tracker System (CATS) was demonstrated to users at
last week’s Science Archive Working Group meeting. Positive feedback
was received. Development of the system will continue with releases of
new evaluation versions during the next few months.

Training began on the Multimission Image Processing Laboratory (MIPL)
Cassini Downlink and Reconciliation Subsystem (CDRS). This is the
automated telemetry processing and evaluation process. Training covers
starting/stopping of servers, visibility into the processes, manual
intervention and configuration of user’s accounts and privileges.

A delivery coordination meeting was held for Mission Sequence Subsystem
version D9.1

SpaceRef staff editor.