3 min read

Cassini Significant Events 09/15/10 – 09/21/10

The most recent spacecraft telemetry was acquired on Sept. 21 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/mission/presentposition/.

Wednesday, Sept. 15 (DOY 258)

Orbit Trim Maneuver (OTM) #261A was performed today. This was the apoapsis maneuver setting up for the Titan (T72) encounter on Sept. 24. The main engine burn began at 9:14 PM PDT. Telemetry immediately after the maneuver showed a burn duration of 158.75 seconds, giving a delta-V of 0.176 m/s, as planned . All subsystems reported nominal performance after the maneuver.

Thursday, Sept. 16 (DOY 259)

Commands were radiated and verified over Canberra's DSS-43 today for the Cassini Plasma Spectrometer (CAPS) Ion calibration pointing, which will execute on the spacecraft Sept. 27, and for CAPS actuator testing during conjunction, when the spacecraft is on thrusters, executing on Sept. 30.

Friday, Sept. 17 (DOY 260)

This week the Composite Infrared Spectrometer (CIRS) took several observations of Saturn's stratosphere, and conducted a mid-infrared mapping observation of Saturn's atmosphere; this observation seeks to map Saturn's upper troposphere and tropopause temperature profile, with spatial resolution of approximately 2 degrees in both longitude and latitude.

Imaging Science (ISS) took images of up to 10 Saturnian satellites in order to better determine their orbits, and imaged a small irregular moon called Kiviuq. ISS performed an observation monitoring Titan's atmosphere; this is part of an on-going campaign to track the long term behavior of the atmosphere. The Visual and Infrared Mapping Spectrometer (VIMS) took a 3 by 3 map of Saturn's atmosphere.

Saturday, Sept. 18 (DOY 261)

Today Cassini supported telemetry testing of the Data Capture and Delivery (DCD) software by participating in the DSN-DCD Project Interface Test (PIT). Further analysis to explain the out-of-sync data received is still ongoing.

Monday, Sept. 20 (DOY 263)

Orbit Trim Maneuver #262, the T72 approach maneuver, was cancelled. There was no science impact and cancellation of the maneuver saved overall delta-V.

Tuesday, Sept. 21 (DOY 264)

This week the working group for the Distributed Object Manager (DOM) transition to the Network File System (NFS) began meeting. Currently, DOM is on the legacy Andrew File System (AFS), a distributed network file system which is no longer supported by the Laboratory. This is an ongoing task slated for completion early in 2011.

A feature story called "Spring on Titan Brings Sunshine and Patchy Clouds" is available on the Cassini web site. It describes research by scientists who have analyzed more than 2,000 VIMS images to create the first long-term study of Titan's weather using observational data that also includes data taken during the equinox period. Equinox, when the sun was directly over the equator, occurred in August 2009. For more information on this subject, link to: http://saturn.jpl.nasa.gov/news/cassinifeatures/feature20100921/.

A lunchtime seminar titled "Microwaving Titan" was presented today by a Cassini RADAR team member. This talk described the present understanding of Titan's surface and how the radar and radiometer worked together to better understand the nature of its surface. This event was sponsored by the JPL Edward Stone Award for Outstanding Publication Seminars, which highlight each recipient's outstanding published research to the JPL Community.