3 min read

Cassini Significant Events 06/29/11 – 07/05/11

The most recent spacecraft telemetry was acquired on July 5 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/mission/presentposition/.

Wednesday, June 29 (DOY 180)

Members of the Cassini Ultraviolet Imaging Spectrograph (UVIS) science team met June 27-29 in Boulder, Colorado, for their annual summer team meeting. They shared science results in the areas of ring dynamics, structure and spectroscopy, Enceladus plume occultations, neutral gas measurements, Saturn aurorae, Titan and Saturn atmospheres, and icy satellite surface compositions and photometry results.

Port 3 products were due today as part of the S70 Sequence Implementation Process (SIP). The products will be merged and sent out to the flight team for review.

Thursday, June 30 (DOY 181)

Science activities this week began near apoapsis. In a continuation of last week’s observations, the Cosmic Dust Analyzer (CDA) completed two more 13-hour interstellar dust observations. The S68 sequence ended with the transmission of the final bits over the 70m antenna at Canberra, Australia. The S69 sequence began with the Imaging Science Subsystem (ISS), Composite Infrared Spectrometer (CIRS), and Visual and Infrared Mapping Spectrometer (VIMS) instruments each making an observation in the Titan monitoring campaign (phase 70.6 degrees and range 3.4 Mkm) to study Titan clouds and weather. ISS then performed astrometric measurements of the small moons Epimetheus, Prometheus, Calypso, Pallene, Helene and Polydeuces. VIMS and CIRS performed an 18 hour observation of the E and G rings. Finally, the fields-and-particles instruments made measurements (23.5 hrs) of the magnetosphere near apoapsis as part of an ongoing study of Saturn's magnetosphere and its spatial and temporal variability.

Friday, July 1 (DOY 182)

Cassini Real Time Operations (RTO) assisted the Downlink Ground System (DGS) team with testing and documentation support of the new AceLog V2 software. A delivery review is scheduled for July 13 in preparation for deployment of the new features and capabilities in this latest version of Acelog, the replacement software for the legacy Operations Log.

Sunday, July 3 (DOY 184)

The S69 sequence began execution today at 2011-184T11:10:00. The sequence will run for 65 days and conclude on September 7. During that time there will be five segments; three cross-discipline and two Saturn segments, with no targeted encounters. Two Orbit Trim Maneuvers (OTMs) are scheduled, numbered 288 and 288a.

The Spacecraft Operations Team (SCO) changed the attitude control mode from Reaction Wheel Assembly (RWA) to Reaction Control Subsystem (RCS) for a four-day wheel rest period starting on June 29, and ending today.

Monday, July 4 (DOY 185)

The Science Planning and Sequencing Team (SPST) conducted testing of the Cassini Information Management System (CIMS) update, V3.6.2, which incorporates a new version of Oracle. The Oracle upgrade must be coordinated with the Cassini Operations Reference Encyclopedia (CORE) as well. A Delivery Coordination Meeting (DCM) is scheduled for July 13 for CIMS and CORE to coordinate the switch-over to the new version of Oracle.

Tuesday, July 5 (DOY 186)

Attitude and Articulation Control Subsystem (AACS) Periodic Engineering Maintenance was done today. This activity, performed approximately every 90 days, spins up the backup reaction wheel assembly to 100 rpm for lubrication purposes and exercises the back-up Engine Gimbal Assembly.