Cassini Significant Events — 10/20/05 – 10/26/05

Cassini Significant Events -- 10/20/05 - 10/26/05

October 28, 2005

(Source: Cassini Project)

The most recent spacecraft telemetry was acquired Wednesday, October 26,
from the Madrid tracking stations. 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 .

Thursday, October 20 (DOY 293):

Cassini scientists participated in a public forum entitled "Saturn: a
Ring-Side View from Cassini-Huygens" at the third annual Geologic Society of
America (GSA) meeting last week. Six hundred fifty people attended the
public session, at least half of whom were children. Cassini posters and
bookmarks were distributed to all attendees. The event was taped and will
be out on the GSA webpage in December.

The Target Working Teams and Orbiter Science Teams delivered their S19
Aftermarket products today. The Science Operations Plan Update process for
this sequence starts on Monday, November 3.

Friday, October 21 (DOY 294):

Cassini Operations began official use of a new MGSS Configuration Management
system for sequence change requests, waivers, instrument expanded block load
forms, flight software load forms, inventory change authorizations, real
time commands, and engineering change requests. The system has
multi-mission capability and will by shared by nine other flight projects at
JPL.

The DOY 301-303 Titan/Saturn Live Inertial Vector Propagator (IVP) update
kickoff meeting was held today. The orbit determination solution that was
used for OTM-39 will also be used for this process.

Orbit trim maneuver (OTM) #39 was completed today. This is an apoapsis
maneuver setting up for the Titan 8 targeted encounter on October 28. The
reaction control subsystem burn began at 9:15 AM PDT. A "quick look"
immediately after the maneuver showed the burn duration was 96.6 sec, giving
a delta-V of approximately 89.8 mm/s. All subsystems reported nominal
performance after the maneuver.

An incredible Cassini image of Dione with Saturn and the rings is Astronomy
Picture of the Day today.

Monday, October 24 (DOY 297):

Starting Sunday and continuing today, the Visual and Infrared Mapping
Spectrometer (VIMS) performed observations of the E ring from 30-40 Saturn
radii in order to build up spectra at different phase angles. VIMS also
acquired data for eleven hours for a global map of Saturn.

Uplink Operations sent the following real-time commands to the spacecraft
today: Cassini Plasma Spectrometer S15 telemetry rate increase for HST
observations to execute on Wednesday, a lowering of Magnetospheric Imaging
Instrument voltage to execute on Saturday, and an Ion and Neutral Mass
Spectrometer flight software patch to execute on Thursday.

At a Go/No go meeting this morning, the Live IVP Update for DOY 301-303 was
cancelled. Later in the day it was determined to cancel OTM-40 as well.
OTM-40 would have been less than the minimum delta-V of 10 mm/s, coming in
somewhere around 6.8 mm/s, it was not required to remain on the tour
trajectory, and was not necessary to meet the science sequence pointing
requirements.

Tuesday, October 25 (DOY 298):

A Radar trigger for the Titan 8 flyby was uplinked to the spacecraft today.
The command will execute tomorrow and assist the instrument in taking
synthetic aperture Radar scans of the Huygens Probe landing site when
Cassini passes by around closest approach.

A Cassini-Huygens Analysis and Results of the Mission (CHARM) teleconference
today covered "Highlights of Radio and Plasma Wave Science Results from
Early in Cassini's Orbital Tour."

Wednesday, October 26 (DOY 299):

A close-up picture of the surface of Dione showing fractures, grooves, and
craters in the ice and rock is Astronomy Picture of the Day today.

The S18 SOP Update project briefing and waiver meeting was held today. A
handoff package has been generated for this sequence in support of the final
sequence development process that begins next week.

The Aftermarket Process for the S20 sequence began today. This 5-week
process will address proposed changes that require re-integration of the
segments contained in the S20 sequence. All science and engineering
proposed changes that involve modifications to key shared resources
including, but not limited to, spacecraft attitude, data volume, observing
time, op modes, telemetry modes, and waypoints, require submission of a
formal request revision or addition. All proposed science and engineering
changes must be submitted by end of day today. On Friday, October 28, there
will be an Assessment meeting with the Project Scientist to scope out these
proposed changes.

A Cassini internal Tour Science Talk was presented today on Ultraviolet
Imaging Spectrograph science results on Saturn's ring system.

Upcoming Event:

Weather permitting, public viewing of the planet Mars will be provided by
Saturn Observation Campaign and Cassini Outreach volunteers with telescopes
on Saturday, October 29th, at Library Park, Myrtle and Lime Streets,
Monrovia, CA. Mars Opposition, when our neighbor planet will be 69 million
km from Earth, occurs on October 29.

Wrap up:

Check out the Cassini web site at http://saturn.jpl.nasa.gov for the latest
press releases and images.

The Cassini-Huygens mission 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, manages the
Cassini-Huygens mission for NASA's Science Mission Directorate, Washington,
D.C. JPL designed, developed and assembled the Cassini orbiter.