Cassini Significant Events 01/02/08 - 01/08/08

January 10, 2008

(Source: Cassini Project)

The most recent spacecraft telemetry was acquired on Tuesday, Jan. 8, from the Goldstone tracking complex. 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:

Wednesday, Jan. 2 (DOY 002):

As a result of the very accurate execution of Orbit Trim Maneuver (OTM) #141 and a favorable direction of the predicted flyby error at Titan 40, cancellation of OTM 142 was predicted to save about 0.2 m/s. Further, the trajectory without OTM-142 is "closer" to the reference trajectory than the predicted trajectory with OTM-142, thus minimizing the need for pointing updates. OTM-142, originally scheduled for today, has been cancelled.

Thursday, Jan. 3 (DOY 003):

Non-targeted flybys occurred today of Dione, Pallene, Janus, Daphnis, and Prometheus.

The first detailed views of the high latitudes of Saturn reveal a matched set of hot cyclonic vortices, one at each pole. The source of the heat is a mystery, and while scientists already knew about the hot spot at Saturn's south pole from previous observations by the W. M. Keck Observatory in Hawaii, the North Pole vortex was a surprise. For the full story link to:

Friday, Jan. 4 (DOY 004):

The sixth non-targeted flyby of the week occurred today, this time of Pandora.

Saturday, Jan. 5 (DOY 005):

Traveling at 6.3 km/sec, Cassini flew past Titan for the T40 targeted encounter today. The flyby occurred at an altitude of 1010 km, with closest approach occurring around 3:00 PM Pacific Time.

For this event, the Visual and Infrared Mapping Spectrometer (VMIS) performed high-resolution spectral mapping of the Huygens Probe landing site, searching for changes since the beginning of the mission. VIMS also searched for volatile transport and studied cloud formation and evolution. T40 also featured two separate stellar occultations to study the structure of Titan's atmosphere. VIMS observed the star Alpha Bootes, and the Ultraviolet Imaging Spectrograph (UVIS) was pointed toward Alpha Lyra.

Ion and Neutral Mass Spectrometer (INMS) observations took advantage of the T40 day-side pass through the flank of the magnetospheric interaction region near noon local time. This is where energetic ion precipitation will have a maximum effect on the thermosphere and ionosphere. These observations will help to determine the atmospheric and ionospheric composition and the thermal structure of Titan.

A complete mission description of this flyby may be found at:

Monday, Jan. 7 (DOY 007):

Today Imaging Science used the narrow angle camera to make an ansa movie of the outer edge of the A ring and Keeler gap, the Composite Infrared Spectrometer performed mid-infrared monitoring of the F ring, and the Magnetospheric and Plasma Science (MAPS) instruments continued the magnetospheric boundary campaign. For the MAPS campaign, the Cassini Plasma Spectrometer (CAPS) made dusk-side observations at a variety of latitudes, and CAPS and the Magnetospheric Imaging Instrument (MIMI) observed Saturn's magnetospheric boundary near noon from a highly-inclined orbit.

Tuesday, Jan. 8 (DOY 008):

In the wee hours of today, members of the Spacecraft Operations Office (SCO) began loading the AACS A8.7.6 flight software update to the spacecraft. Passes for this activity continue through Jan. 13. Version 8.7.6 will update the default thruster force magnitudes and the secondary safing vector pair for the time period from Jan.11, 2008 through mid-June 2009.

The final sequence development process began today for S39. Sequence leads hosted the kickoff meeting, and released the integrated and stripped Spacecraft Activity Sequence Files for review by the team.