NASA Cassini Significant Events 09/03/08 – 09/09/08
The most recent spacecraft telemetry was acquired on Sept. 9 from the Deep Space Network tracking complex at Madrid, Spain. 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, Sept. 3 (DOY 247):
The minimum Sun-Earth-Probe (SEP) angle of 1.67 deg occurred today. This is solar conjunction, and is the time of greatest interference from the Sun on Cassini’s telecommunications link. The SEP angle will now increase over the next five days until the angle reaches 5 degrees and conjunction officially ends. Until that time, Spacecraft Operations (SCO) will continue collecting statistics on commanding capability and interference levels. Radio Science (RSS) has been performing the annual RSS solar corona characterization experiment since Aug. 26. This experiment will continue until Sept. 15.
A non-targeted flyby of Methone occurred today.
The Spacecraft Office Engineering Activities Review for S49 occurred today. At this meeting the spacecraft team reviews all engineering activities to be performed during that sequence.
Friday, Sept. 5 (DOY 249):
Cassini has detected two new ring arcs around Saturn co-orbiting with the tiny moons Anthe and Methone, previously discovered by Cassini during its primary mission. This is further evidence that most of the planet’s small, inner moons orbit within partial or complete rings. Findings like these help scientists to understand how the orbits of the bodies and ring material in a planetary system are configured by their mutual gravitational resonances. For the full story link to: http://saturn.jpl.nasa.gov/news/sig-event-details.cfm?newsID=869
Today Cassini begins to come out of Solar Conjunction as the SEP angle climbs out of the “loss of telemetry zone” of less than 2 degrees. A playback of Magnetospheric and Plasma Science (MAPS) data recorded during conjunction is scheduled as soon as telemetry is re-established today.
Sunday, Sept. 7 (DOY 251):
With the SEP angle now past the 3 degree mark, the Cassini Plasma Spectrometer (CAPS) begins the first non-Earth pointed science data acquisition with a slew to an orientation favorable for collecting magnetospheric data. This is followed by an on-going Imaging Science (ISS) campaign to further deduce the orbits of some of the lesser-known satellites of Saturn. The day ends with a Visual and Infrared Mapping Spectrometer (VIMS) and Composite Infrared Spectrometer (CIRS) investigation of the unlit side of Saturn’s rings.
Monday, Sept. 8 (DOY 252):
A project-wide Operational Readiness Test (ORT) is set to begin today and run for the next three days. The purpose of the test is to train new flight team members in anomaly response and identify areas where the process may be improved.
Commanding began today for S44 with the uplink of five Instrument Expanded Block (IEB) files. Uplink Operations has verified that all the files have been properly registered on-board the spacecraft. An additional IEB will be uplinked tomorrow, the background sequence will go up on Sept. 11, and the sequence will begin execution on Saturday, Sept 13.
Tuesday, Sept. 9 (DOY 253):
VIMS continues its search for auroras in Saturn’s north polar region today. Simultaneously, the MAPS instruments will directly sample the magnetic and plasma environment surrounding Saturn as Cassini crosses the magnetic field lines feeding auroral activity. The day ends with a joint Optical Remote Sensing (ORS) campaign of the moon Tethys.
