Status Report

Cassini Significant Events for 01/23/03 – 01/29/03

By SpaceRef Editor
January 31, 2002
Filed under , ,
Cassini Significant Events for 01/23/03 – 01/29/03

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, January 29. 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 High
Frequency Receiver (RPWS) calibrations, uplink and execution of a Cosmic
Dust Analyzer flight software checkout mini-sequence, Composite InfraRed
Spectrometer functional and mute/unmute tests, and uplink and execution
of an ACS Reaction Wheel Assembly friction test.

The Spacecraft Operations Office power analyst has distributed the
quarterly Radioisotope Thermoelectric Generator (RTG) report. The RTGs
continue to provide power at the expected levels and are trending

This week JPL hosted members of the Cassini science community and
interested members of the flight team for Cassini’s #30th meeting of the
Project Science Group (PSG).

The Science Planning manager gave a presentation at the PSG meeting that
included metrics for Science Operations Plan (SOP) development. SOP
integration is 55% complete covering revs 0, A-C and 1-26, and SOP
implementation is 14% complete covering tour sequences S9 through S14.
The SOP will be completed by January 2005.

The Command and Data Subsystem (CDS) Flight Software Team held a
successful Software Requirements and Certification Review for version V9
of the CDS flight software. This final delivery is a major milestone in
the spacecraft flight software development. V9 will provide all the CDS
capabilities required for orbital tour operations as well as the Saturn
Orbit Insertion and Probe Relay. The Flight Team will uplink the
software in February and begin a detailed checkout of the software on
the spacecraft beginning in late March.

The Ion and Neutral Mass Spectrometer Instrument (INMS) engineering
model and support equipment arrived at JPL. The instrument will be
incorporated into the spacecraft bus in the Cassini Integrated Test Lab
(ITL) for tests of INMS flight software loading from the Command and
Data Subsystem. An additional objective of the tests will be to validate
the process of obtaining ITL bus data and converting it to a format for
use by the instrument’s Remote Terminal Interface Unit (RTIU).

A delivery coordination meeting was held to review the functionality of
Spacecraft Operations Office Propulsion Tools V1.0, and to coordinate
installation. The delivery was comprised of the Bipropellant System
Performance Tool, used to generate bipropellant propulsion system
performance predictions and reconstructions, the Monopropellant System
Performance Tool, used to generate monopropellant propulsion system
performance predictions and reconstructions, Tanks Models, used to
calculate the physical properties of five Cassini propellant and
pressurant tanks, and the Mass Properties Model which calculates the
spacecraft dry and wet centers of mass and the wet and dry inertial
properties matrices.

A Cassini Archive Design Peer Review was held this week for the
Magnetospheric Imaging Instrument, Composite InfraRed Spectrometer,
Ultraviolet Imaging Spectrograph, and RPWS instruments. Presentations
showed much progress in team Planetary Data System (PDS) archive plans,
and that help from the project and PDS is needed to resolve open items.
Minutes and action items generated from the Recommendations for Action
will be posted by February 7th.

The Imaging Science Subsystem (ISS) used a new feature of the Remote
Terminal Interface Unit (RTIU) to confirm that a fix to the command
database (CDB) had been implemented correctly. To support RTIU
operation, Instrument Operations has developed a script that will
automatically take an instrument Spacecraft Activity Sequence Files
(SASF) as input, run seqgen and seqtran, and produce a script in a
format that the RTIU can understand. ISS processed the same SASF file
with both the old and new versions of seqgen and seqtran. This
confirmed that the change to the CDB had been made correctly. There
are plans to implement a web page interface to allow RTIU users to
translate their own SASFs. Currently, the scripts must be run by hand.

The Uplink Operations Mission Sequence Subsystem (MSS) Engineer provided
an overview of the MSS D9.0 delivery contents, and an advanced look at
the future schedule, at the PSG meeting on Tuesday. The information was
generally well received with the expected concerns voiced over the delay
in some functionality. The attendees were also made aware of a one-week
delivery slip. This slip will allow time to incorporate some urgent
changes, including support of TCM-19, and redo associated testing.

The Principal Investigator for the RPWS was featured on NPR’s Morning
Edition on 1/23/03. NPR reported: “In space, one cannot hear sounds.
But a new musical work –commissioned by NASA — is based on radio waves
gathered from the far reaches of the solar system. For Morning Edition,
Gayane Torosyan of member station WSUI reports on Sun Rings, composed by
Terry Riley and performed by the Kronos Quartet. The work includes
sounds collected over 40 years by University of Iowa physicist Don
Gurnett.” For more information connect to .

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.

SpaceRef staff editor.