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Significant Event Report for Week Ending 3/12/2004

Cassini Significant Event Report

For Week Ending 03/12/04

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Monday, March 8. 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 .

Cassini has resumed approach science activities following last week's probe checkout. Images of Saturn continue to be taken that will be used to make approach movies to study the planet's atmosphere and its temporal variations, determine wind speeds and cloud properties, and to build up global temperature and composition maps. A map of Saturn's magnetosphere in the ultraviolet will create a 3-dimensional map of the distribution of atomic hydrogen and other atomic species. Cassini continues to monitor the solar wind as it approaches Saturn, including looking for upstream ions and upstream wave phenomena.

Additional activities include the uplink of a Visual and Infrared Mapping Spectrometer mini-sequence containing flight software version 8.1 and instrument expanded blocks, uplink of a Cosmic Dust Analyzer denoising relative timed direct packet, and clearing of the ACS high water marks.

A preliminary port 1 delivery was made for Science Operations Plan (SOP) Implementation of tour sequences S25 and S26. The SOP update process was begun for S02.

Cycle 1 products and the most recent sequence merge products for the C44 Preliminary Sequence Integration and Validation2 Science and Sequence Update Process (SSUP) have been released for review. C44 is the final sequence in the Approach Science subphase.

SOP Update of the S01 sequence concluded this week. A hand-off package was transferred from Science Planning to Uplink Operations. A kick off meeting was then held for the S01 SSUP, and stripped SASF subsequence products were released to all teams. S01 is the first tour sequence.

This week's Tour Science Plan presentation to the flight team covered plans for the flybys of Saturn's icy satellites.

The Navigation Team reported that 75 images containing 117 satellites have been processed from between the start of optical navigation on February 6 through February 27. In addition, the convergence of spacecraft and satellite ephemerides is as expected. Regular processing of radiometric tracking data has begun and the quality is very good. A preliminary reference trajectory using the latest satellite ephemeris has been developed. A final version will be released in the May timeframe.

Delivery coordination meetings were held for Mission Sequence Subsystem (MSS) D10.2, and for the Electronic Command Request Form tool V1.2. MSS D10.2 will be used to support the start of the S02 SOP Update process.

The Navigation and Ancillary Information Facility (NAIF) at JPL announced a "SPICE" Tutorial class that will be held at a hotel near Pasadena, California on May 4-6, 2004. SPICE is an ancillary information system that provides scientists and engineers access to spacecraft orbit, attitude and similar information needed to determine observation geometry used in planning and analyzing space science observations, and to conduct mission engineering planning and analysis. Check http://pds-naif.jpl.nasa.gov/ for further information about SPICE. The class is open to all JPL and contractor personnel, and is also offered to JPL/NASA colleagues - domestic and foreign - who are now participating, or may participate in the future, in any NASA space exploration endeavor where SPICE capabilities could be useful. There are no ITAR restrictions on the material to be presented.

Outreach provided an opportunity for the flight team to attend a Cassini Mission overview for a general, non-technical audience. The presentation was given to acquaint the flight team with the Cassini Speakers and the types of presentations that are given to the public. Sample presentation materials were available for checkout for those interested in joining the Speakers organization.

Outreach hosted a group of informal educators from the Chabot Space and Science Center in Oakland California and the Los Angeles County Museum of Natural History. The attendees were briefed on Cassini science objectives, worked with some of the hands-on education activities available, and were introduced to 'Reading, Writing, and Rings.'

The following data release was posted Friday March 5, 2004:

Methane Image (single filter) of Saturn from ISS NAC: PIA 05381

The image scale is 397 kilometers (247 miles) per pixel. Image details reveal a high, thick equatorial cloud and a relatively deep or thin haze encircling the pole, as well as several distinct latitude bands with different cloud height attributes. It also shows a high atmospheric disturbance, just south of the equator, which has persisted throughout the 1990s in images returned by NASA's Hubble Space Telescope. For more information go to:




Additional information about Cassini-Huygens is online at http://saturn.jpl.nasa.gov.

Cassini will begin orbiting Saturn on July 1, 2004, and release its piggybacked Huygens probe about six months later for descent through the thick atmosphere of the moon Titan. Cassini-Huygens is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Office of Space Science, Washington, D.C.

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