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The most recent spacecraft tracking and telemetry data were collected on May 15 using the Deep Space Network's 70 meter Station 14 at Goldstone, California. Aside from the issues in work with the Ultrastable Oscillator (see the Jan. 5, 2012 Significant Events), the Cassini spacecraft is in an excellent state of health with all its subsystems operating normally. Information on the present position of the Cassini spacecraft may be found on the "Present Position" page at: http://saturn.jpl.nasa.gov/mission/presentposition/.
As the spacecraft proceeded out toward apoapsis, Magnetospheric and Plasma Science (MAPS) observations again made in-situ measurements of Saturn's outer magnetosphere and magnetosheath at low latitude, which means near Saturn's equatorial plane where the spacecraft is currently orbiting. These observations continued through Monday. Interspersed with these activities, the Imaging Science Subsystem (ISS) led the pointing for the optical remote sensing instruments to take repeated measurements of Titan this week to monitor cloud formations at different phase angles and distances.
Wednesday, May 9 (DOY 130)
Part 2 of the 10-week S73 background sequence was uplinked through the Deep Space Network (DSN) to the spacecraft today; its 7649 commands were confirmed aboard after one round-trip light time of 2 hrs, 27 minutes.
Thursday, May 10 (DOY 131)
Negotiations for DSN antenna allocations to support the ten-week S74 sequence that is in work were completed for the first six weeks of the sequence. Work also continued on the ten-week sequences S75, S76, and S77.
Friday, May 11 (DOY 132)
Cassini's orbit count incremented to 166 with apoapsis passage at 2.4 million kilometers from Saturn (about twice the distance of Titan's orbit) going 5,488 kilometers per hour with respect to the planet.
S73 Part-2 commands began controlling the spacecraft.
ISS observed Saturn's moon Erriapus for 8 hours. This dark body is less than 10 kilometers in diameter, and orbits the planet once each 871 days at a distance of more than 17 million kilometers from Saturn.
Saturday, May 12 (DOY 133)
After approval of the maneuver and the command file, Orbit Trim Maneuver (OTM) 321 was uplinked to the spacecraft.
Realtime commands were sent to the spacecraft that will power the Cosmic Dust Analyzer (CDA) back on this Tuesday.
Sunday, May 13 (DOY 134)
Five optical navigation images were taken of Rhea against the background stars.
OTM 321 successfully turned the spacecraft and fired the main engine, providing 8.3 meters per second delta-V. This brought Cassini onto the planned trajectory for the Titan T-83 flyby at 955 kilometers above its surface on May 22.
Monday, May 14 (DOY 135)
The Magnetometer executed a sensor-offset calibration by rotating the spacecraft about its X axis.
The Ultraviolet Imaging Spectrograph began a series of observations that will continue over the next several days, with the Visible and Infrared Mapping Spectrometer, ISS, and the Composite Infrared Spectrometer riding along, to study Saturn's aurora by performing a mixture of slews and fixed pointings at the auroral oval.
Tuesday, May 15 (DOY 136)
The CDA power-on commands executed, and the instrument began operating normally.
The Cassini Plasma Spectrometer team updated some of its instrument's parameters by realtime command using the automated sequence processor.