Status Report

NASA Cassini Significant Events for 08/07/03 – 08/13/03

By SpaceRef Editor
August 18, 2003
Filed under , ,
NASA Cassini Significant Events for 08/07/03 – 08/13/03

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Tuesday, August 12. 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 .

The C38 background sequence concluded this week with playback of science
data recorded during Saturn Orbit Insertion Demonstration, a
Magnetospheric Imaging Instrument (MIMI) Instrument Expanded Block (IEB)
load test and a Radio and Plasma Wave Science (RPWS) High Frequency
Receiver calibration. The flight team sent real time commands to power
on the Ion and Neutral Mass Spectrometer (INMS) and load the instrument
with IEBs. The team also loaded the INMS flight software (FSW) onto the
Solid State Recorder (SSR).

C39 background sequence was radiated to the spacecraft on Thursday,
August 7, and began execution on Sunday August 10. C39 contains
numerous instrument checkout and calibration activities that must be
performed prior to the approach science phase which begins in January of

Initial activities included IEB loads from the SSR for the Cassini
Plasma Spectrometer (CAPS), Ultraviolet Imaging Spectrometer (UVIS), and
RPWS, a Magnetometer calibration, a Composite Infrared Spectrometer
(CIRS) module test, CAPS and Visual and Infrared Mapping Spectrometer
(VIMS) FSW uploads. Also uplinked were a mini-sequence for INMS FSW
checkout, pressure test, and all C39 INMS checkout activities, and a
RPWS high rate observation and IEB exercise.

The INMS team reports that the instrument is now on, in sleep mode, and
operating normally. The INMS instrument was last active during the
instrument checkout period in cruise sequence C11 in January of 1999.
The instrument has been off since then per plan.

A kick-off meeting was held for the start of the Science Planning
Virtual Team process for cruise sequence C42. C42 is the first of three
approach science sequences just prior to the start of tour operations.
This is an intense period of time while the flight team transitions
between cruise and tour processes and procedures, and we gather valuable
science and navigation data as we draw closer to Saturn.

The science and engineering teams have delivered sequence products for
preliminary port one of the science operating plan for tour sequences
S03 and S04, and port two for cruise sequence C40.

The Science Planning team presented an overview of the aftermarket
process. Cassini personnel are currently creating the basic commands for
pointing, telemetry, and power to control the spacecraft for each of the
41 sequences in the four-year tour. When the process for a sequence
concludes, the sequence is archived for as long as two to four years.
During this time, science and engineering teams may work on the liens
identified and make a small number of changes to the baseline plan. New
discoveries and changes in the spacecraft or instruments may also
necessitate a change in the plan. The presentation outlined guidelines
and constraints that will govern this work, and summarized the five week
aftermarket process where changes are prioritized and
approved/disapproved so that a complete package may be created for the
science operations plan (SOP) update.

A Software Review Certification Requirement delivery meeting was held
for the MIMI v7.0.0 FSW build. The board granted preliminary approval of
the FSW for preparation of the uplink files with final approval to occur
after completion of an additional regression test and update of the
release documents.

The Multi-mission Image Processing Laboratory (MIPL) version D30
software is now officially in use as the operational software set. All
Cassini MIPL tour hardware has been configured and is now on-line. This
includes seven Sun Blades for telemetry processing, and eight terabytes
of storage for the Imaging Science Subsystem (ISS) and VIMS
life-of-mission storage. The multi-mission database server machine was
also upgraded to meet performance needs.

System engineering held a Delivery Coordination Meeting (DCM) for three
Spacecraft Operations Office tools. The MAPDF_GEN Generator
(MAPDF_GEN): is used to create a Maneuver Performance Data File (MAPDF)
for use by navigation in the maneuver design process. The Maneuver
Design tool (MDT) determines the commands necessary for the spacecraft
to perform a trajectory correction maneuver. The Best Estimate Conic
(BECON) tool determines a single best-fit conic orbit for the orbiter as
it flies past Titan during the Huygens probe mission. The orbit is used
on board the spacecraft to provide pointing control.

A DCM also was held for the Kinematic Prediction Tool (KPT) v9.2. The
DCM accepted the delivery but agreed to wait 1-2 weeks for additional
testing prior to installation on the operations network.

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.