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Cassini is orbiting Saturn with a 31.9-day period in a plane inclined 48.1 degrees from the planet's equatorial plane. The most recent spacecraft tracking and telemetry data were obtained on Feb. 18 using the 70-meter diameter Deep Space Network (DSN) station at Goldstone, California. Except for the science instrument issues described in previous reports (for more information search the Cassini website for CAPS and USO), the spacecraft continues to be in an excellent state of health with all of its subsystems operating normally. Information on the present position of the Cassini spacecraft may be found on "Eyes on the Solar System" at http://1.usa.gov/1mfK6fa.
Two hundred eighteen people, mostly scientists, from JPL, other NASA centers, and domestic and foreign research centers and universities, met at JPL this week as part of Cassini's 62nd Project Science Group meeting. While their instruments were carrying out observations a billion miles away under control of the S82 command sequence, they held team meetings and working groups and gave plenary-session presentations. The normal routine proceeded as well, with Cassini's Sequence Implementation Process teams working on the 10-week command sequences S83, S84, and S85. Planning also continued for the 2016 start of Cassini's F-ring and Proximal Orbits phase.
Wednesday, Feb. 12 (DOY 043)
The Imaging Science Subsystem (ISS) continued a 37-hour observation of the dark-face ring spokes (http://go.usa.gov/4WGP) at high-phase illumination to make a movie and search for spoke periodicities. The Composite Infrared Spectrometer (CIRS) also made observations while ISS controlled the pointing.
As usual, the direct-sensing Magnetospheric and Plasma Science instruments collected data continuously during the week, regardless of where the spacecraft was aiming its remote-sensing telescopic instruments or its high-gain antenna.
A web page was created to show off images produced by members of the public who turn Cassini data into works of art, and to solicit new submissions: http://saturn.jpl.nasa.gov/photos/amateurimages.
Thursday, Feb. 13 (DOY 044)
ISS, CIRS and the Visible and Infrared Mapping Spectrometer (VIMS) performed an observation in the Titan monitoring campaign from a distance of 1.9 million kilometers.
Friday, Feb. 14 (DOY 045)
ISS made observations at high-phase illumination for 13 hours, again for a dark-face ring-spoke movie. CIRS rode along again. This observation was repeated on Sunday.
Based on the latest tracking data from the DSN, the flight team created and approved commands to carry out Orbit Trim Maneuver (OTM)-372 on Monday, and sent them to the spacecraft after midnight local time.
Saturday, Feb. 15 (DOY 046)
Following a round-trip light time of two hours 44 minutes, the flight team confirmed that the OTM-372 commands had been properly received and registered aboard the spacecraft. This OTM will adjust Cassini's flight path for its T-99 encounter with Titan on March 6.
Sunday, Feb. 16 (DOY 047)
The DSN carried out another routine nine-hour session today, tracking Cassini with Doppler and ranging measurements, and providing digital communications via telemetry and command. All told there were six such DSN passes with the spacecraft this week.
Monday, Feb. 17 (DOY 048)
VIMS made a two-minute storm-watch observation of Saturn. ISS then executed an hour-long observation in the satellite orbit campaign to sight objects orbiting near the planet.
Right on time and three days before apoapsis passage, the OTM-372 commands turned the spacecraft and fired Cassini's main rocket engine for 9.6 seconds; this provided the desired 1.7 meter per second change in velocity.
After the OTM, the Cosmic Dust Analyzer (CDA) started a 15-hour observation to measure dust orbiting Saturn in the retrograde direction.
An image of Saturn's moon Dione was featured today, in which its wispy surface fractures are visible: /resources/15980
Tuesday, Feb. 18 (DOY 049)
VIMS rode along while ISS carried out another satellite orbit campaign observation for an hour. ISS then performed another two-minute storm-watch. Finally, ISS began 28 hours of observations for another dark-face ring spoke movie.