Status Report

NASA Cassini Significant Events for 02/26/04 – 03/03/04

By SpaceRef Editor
March 5, 2004
Filed under , , ,
NASA Cassini Significant Events for 02/26/04 – 03/03/04

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, March 3. 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 .

C43 activities continued this week with a Composite InfraRed Spectrometer
mirror calibration, RADAR Instrument Expanded Block (IEB) exercise, Optical
Navigation SSR IEB load, Cassini Plasma Spectrometer power on/off and high
voltage IEB trigger Immediate/Delayed Action Program uplink, Radio and
Plasma Wave Science solar wind observation, Imaging Science Subsystem (ISS)
Saturn Approach movie, and spacecraft periodic engineering maintenance.

The prime activity this week was execution of the Huygens Probe Relay
Critical Sequence demonstration. Prior to the event, all instruments were
either turned off or muted and placed in sleep. 24-hour coverage was
provided for the four days of the demonstration by the Goldstone, Madrid,
and Canberra DSN complexes. Personnel from the Spacecraft Operations Office,
Mission Support and Services Office, Probe, and the Instrument Operations
Distributed Operations Coordinator supported the exercise.

The activity began with uplink of sequences to the Solid State Recorder, and
culminated in the delivery of probe data to the Huygens Project Operations
Center in Darmstadt, Germany. The demonstration included the spacecraft
turning to the Probe Relay attitude, recording approximately six hours of
simulated Probe data, then turning back to Earth to downlink the Probe data
at the expected mission rates to the 70 meter DSN station at Goldstone,

In the last week, 185 ISS images were acquired and distributed before the
instrument went to sleep for the Probe demonstration. So far in Approach
Science, 994 ISS images have been acquired. Of those, 84 are optical
navigation images.

The C44 Preliminary Sequence Integration and Validation Sequence Change
Request approval meeting was held this week.

Preliminary and official port 2 deliveries were made for Science Operations
Plan (SOP) Implementation of tour sequences S23 and S24. A wrap-up/program
briefing/waiver disposition meeting was held for SOP Update of S01, the
first tour sequence. Sequence generation will begin next week.

Science Planning launched a series of Tour Science Plan presentations to the
flight team with an historical overview of the timeline and process that led
to selection of the current baseline tour, and how that tour would then be
segmented and integrated with detailed science requests from which the tour
sequences would be developed.

Members of Program Science and SCO met to discuss G ring brightness in the
star tracker during the ascending ring plane crossing just prior to Saturn
Orbit Insertion. Further dialogues will be held with some ring scientists
to obtain information on G ring brightness, and some G ring scientific
papers were identified for SCO to reference. Another topic discussed
involved small satellites, 3.5 to 7 km diameter, that might be confused as
stars. The Voyager upper limit for this region was 10 km. Hubble images
can detect moonlets down to 3 km, but no Hubble searches in the vicinity of
the G ring have been done.

SCO delivered ground software for Maneuver Automation Software (MAS) version
4.3. The MAS tool takes the Navigation solution for a trajectory correction
maneuver and builds a sequence ready for uplink to the spacecraft in less
than 30 minutes.

Additional Delivery Coordination meetings were held for the Navigation T1.1
and Mission Sequence Subsystem D10.2 software.

Outreach personnel participated in a career day at San Dimas High School in
San Dimas, California. Eighty students attended a two-hour presentation and

The "Where is Cassini Now?" page of the Cassini website has been updated to
reflect the spacecraft’s pending arrival at Saturn. The new page can be
viewed at:

The release of the latest Saturn image resulted in the largest traffic
volume ever seen on the Cassini home page. The previous high was the
Astronomy Picture of the day on Dec.10 with ~ 638,000 requests, 3.8
gigabytes of information transferred, ~ 14,000 unique visitors and 38,000
pages. The Feb. 27th release put that to shame with 1,813,319 requests,
12.71 gigabytes of information transferred, 21,153 unique visitors and
105,528 pages. Overall, traffic to the Cassini site has increased since the
Mars rover landings, roughly quadrupling from previous months’ averages.
The website can be located at:

MSNBC recently reported on an update to a Cassini website for children.
With the Cassini spacecraft sending regular postcards from Saturn and its
surroundings, a scientific storyteller sent a timely reminder regarding
NASA’s Jet Propulsion Laboratory and the Cassini children’s tale. The site
can be located at:

An additional MSNBC report described Saturn and its rings taking center
stage in the Cassini spacecraft’s latest picture, snapped from 69.4 million
kilometers away

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.