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Cassini Significant Events 10/14/09 – 10/20/09

The most recent spacecraft telemetry was acquired on Oct. 20 from the Deep Space Network tracking complex at Canberra, Australia. The Cassini spacecraft is in an excellent state of health and all subsystems are operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" page at: http://saturn.jpl.nasa.gov/operations/present-position.cfm.

Wednesday, Oct. 14 (DOY 287):

The main engine cover was opened today completing the 51st in-flight cycle of the cover. Cycle #52 will begin on Oct. 30.

Cassini scientists participated in a press briefing at NASA headquarters today on constructing the first comprehensive sky map of our solar system.

Observations from Cassini complemented data collected by NASA¹s Interstellar Boundary Explorer. Images from the Ion and Neutral Camera on Cassini¹s Magnetospheric Imaging Instrument suggest that the heliosphere, the region of the sun¹s influence, may not have the comet-like shape predicted by existing models. In a paper published Oct. 15 in Science Express, scientists presented a new view of the heliosphere, which suggests that it moves more like a slippery ball through smoke. The "smoke" in this case is the interstellar medium, the matter that fills the local region of our galaxy and is forced to flow around the heliosphere. Here are the links to the full story, images, and video:

Thursday, Oct. 15 (DOY 288):

Orbit Trim Maneuver (OTM) #218 was performed today. This was the cleanup maneuver from the Titan 62 encounter on Oct. 12. The main engine burn began at 7:00 PM PDT. Telemetry immediately after the maneuver showed a burn duration of 4.97 seconds, giving a delta-V of 0.845 m/s. All subsystems reported nominal performance after the maneuver.

Today marked the 12th anniversary of the launch of the Cassini Spacecraft.

The Instrument Operations Working Group met today to view presentations relating to changes in operations processes for the proposed Extended Extended Mission (XXM). Topics included the XXM Uplink Sequence Implementation Process that combines and streamlines the Science Operations Plan Process and the Science and Sequence Update Process, XXM RBOT Response, and XXM Integration rules, contingency plans, and pointing. These same presentations will be given next week at the Tuesday plenary session of the Cassini Project Science Group meeting.

Friday, October 16 (DOY 289):

At periapsis on orbit #119, RADAR created a global map of Saturn¹s equatorial region. During the week, Imaging Science (ISS) observed the transits of Mimas across Rhea and of Tethys across Titan, and performed lightning searches on Saturn. The Visual and Infrared Mapping Spectrometer (VIMS) created regional and global mosaics of Saturn, and observed the E and G rings. The Ultraviolet Imaging Spectrograph (UVIS) executed several slow extreme and far ultraviolet scans across Saturn¹s visible hemisphere, and mapped volatiles in the immediate neighborhood of Enceladus to test the connection of volatile changes to plume eruptions. The Cassini Plasma Spectrometer (CAPS) performed a Magnetosphere and Plasma Science (MAPS) survey and led the pointing for the MAPS team Solar Wind-Aurora Campaign observations. The Composite Infrared Spectrometer (CIRS) measured oxygen compounds in the stratosphere of Saturn.

Sunday, Oct. 18 (DOY 291):

An AACS prime reaction wheel friction test took place on Oct. 18. Wheels 1, 2, and 4 were spun up to +/-900 rpm and then allowed to coast down to 0 rpm.
Performance was consistent with past friction test results.

Monday, Oct. 19 (DOY 292):

Cassini scientists, operations personnel, and flight team members gathered this week for the 49th Project Science Group meeting. Instrument Team meetings, working group meetings, and plenary sessions were held all week.

Tuesday, Oct. 20 (DOY 293):

Today students from across the United States who entered the Cassini Scientist for a Day essay contest called in and asked questions of Cassini scientists during a live USTREAM TV webcast. Instrument scientists and observation designers answered the students' questions. Over 2,000 students in 68 classrooms watched the live event. The webcast has been archived and is available at http://www.ustream.tv/recorded/2391081

Orbit Trim Maneuver (OTM) #219 was performed today. This was the apoapsis maneuver setting up for the Enceladus 7 encounter on Nov. 2. The main engine burn began at 6:29 PM PDT. Telemetry immediately after the maneuver showed the duration was 24.42 seconds, giving a delta-V of 4.16 m/s. All subsystems reported nominal performance after the maneuver.