Cassini Significant Events
for
The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Monday, March 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 http://saturn.jpl.nasa.gov/operations/present-position.cfm.
Science observations this week
included Saturn approach movies to study the planet's atmosphere and its
temporal variations, searches for new satellites, observations of Titan and
searches for diffuse ring material, and solar wind observations. The
Magnetometer Subsystem performed a Science Calibration Subsystem flight
calibration, and commands were sent to the spacecraft to power on the Cassini
Plasma Spectrometer and perform Real Time Interrupt
testing.
Files for C44 were uplinked to the
spacecraft this week. They included the background sequence, instrument
expanded blocks, and an absolute timed Immediate/Delayed Action Program to
perform an ACS Reaction Wheel Assembly bias. C44 begins execution on
Thursday, April 1.
During C44 the first time event
"rocking downlink" will be performed for the Cosmic Dust Analyzer (CDA).
During the downlink, the spacecraft rolls about the Z-axis in a back and forth
manner. CDA will be performing rocking downlinks on 13
April.
Spacecraft Operations completed
the Integrated Test Lab (ITL) dry run for the ACS flight software update version
A8.6.7 on Thursday, 4/1/04. The test was important because this is the
first time in flight an ACS computer will be reset and loaded with a flight
software update during an on-going background sequence. The test was successful
in that it did catch a missing vector needed for the C44 background. The missing
vector has been added and the test will be re-run next
week.
Spacecraft Operations delivered
version 10.3 of both IVP and KPT. This is the planned tour version of these
ground software tools.
The Sequence Team released the
preliminary version of the S01 background sequence and Phoebe Live Movable
Block. Team members are in the process of reviewing the integrated
sequence.
In the last week, 265 Imaging Science
Subsystem (ISS) images and 36 Visual and Infrared Mapping Spectrometer (VIMS)
cubes were returned and distributed, bringing the total of images acquired since
the start of Approach Science up to 1969, and the number of cubes up to
663.
The Science Operations Plan Update
process for S02, which includes the science occurring during and after the
Saturn Orbit Insertion burn, had its official port 1 delivery this week.
The team and engineering input products were merged and the merged product was
handed off to ACS to perform the end-to-end pointing analysis. The S02
product will be handed off to the SSUP process on April
9.
Tour Science Plan presentation #5 to
the flight team this week was part 2 of two parts on the Titan Orbiter Science
Team plans for tour. This team was responsible for integration of science
activities for the 44 targeted Titan flybys during the prime
mission.
Delivery coordination meetings were
held this week for Version 5.2 of AP_DOWNLINK consisting of bug fixes and new
telemetry predicts, version 10.3 of Kinematic Prediction Tool and Inertial
Vector Propagator, and Radio Science Subsystem tools LMBTRK Version 1.2 which
incorporated the hard-limb approximation for faster calculations in the cases of
large bending angles, for which high accuracy is not needed, POSTLM Version 1.1
which incorporated optimization and the capability to handle both ingress and
egress, and BISTAT Version 1.1 which incorporated atmospheric effects on the ray
path.
A Delivery Review was held for the
Multi Mission Image Processing Laboratory point delivery D32.0.1. Testing
results were reported and no issues were brought up. Operations were then halted
for a validation and switchover period. This integrated system was then brought
on-line as the operational system for Tour.
New content and graphics were
released to the Saturn Observation Campaign website. Enhancements include
compliance with the design features of the NASA portal, new information, and
announcement of application process for new SOC members. The site can be
accessed at: http://soc.jpl.nasa.gov
Cassini Outreach is performed not only by members
of the Outreach staff located at JPL, but also by members of the flight
team. A Radio and Plasma Wave Science instrument team member gave a series
of talks in his local community to 22 first grade students at
Wind-blown clouds and haze high in Saturn's
atmosphere are captured in a movie made from images taken by the Cassini narrow
angle camera between Feb. 15 and
In the week that sees the 375th
anniversary of the birth of the Dutch astronomer Christiaan Huygens, an
international conference entitled "Titan: From Discovery to Encounter" is taking
place, from 13 to 17 April, at ESA's European Space Research and Technology
Centre (ESTEC), Noordwijk, the Netherlands.
The conference will bring together an
international team of space scientists and historians to discuss topics such as:
- Christiaan Huygens and his connection with other 17th century scientists, such
as Cassini, Descartes and Newton; - observation of Saturn and its moons
from the 17th century to today; - the scientific objectives of the
Cassini/Huygens mission and its latest observations on the way to the Saturnian
system.
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
Cassini Outreach
Cassini
Jet Propulsion Laboratory
California Institute of Technology
National Aeronautics and Space Administration
