NASA Cassini Significant Events for 01/09/08 - 01/15/08

Status Report From: Jet Propulsion Laboratory
Posted: Monday, January 21, 2008


The most recent spacecraft telemetry was acquired on Tuesday, Jan. 15, from the Madrid 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. 9 (DOY 009):

Yesterday at the Mission Planning Forum, the two topics presented were what to do with the Titan 44 approach maneuver, which occurs on the same day as the Mars Phoenix entry-descent-landing event, and a dust hazard update. Significant changes in the dust models have come about based on Cassini data. This information needs to be folded into mission planning. The Mission Planning manager will present the information on new dust hazards and recommend protective measures during the proposed Extended Mission.

The 11th archive delivery of prime mission science data to the Planetary Data System occurred earlier this month. This delivery spans data collected in the time range of Jan. 1, 2007 to March 31, 2007. The next archive delivery is scheduled for April 1. It is anticipated that this archive will contain a new Radar product - Synthetic Aperture RADAR topographic maps.

The end of today begins the start of orbit 56 with Cassini at an apoapsis distance of 30.2 Rs, an inclination angle of 46.6 degrees, and a 31-degree phase angle. The 12-day orbit finds the Composite Infrared Spectrometer (CIRS) taking measurements for determining upper troposphere and tropopause temperatures of Saturn. The Cassini Plasma Spectrometer (CAPS) and Magnetospheric Imaging Instrument (MIMI) continue dusk-side and near-noon magnetospheric observations as part of their magnetospheric boundary campaign. The Visual and Infrared Mapping Spectrometer (VIMS) obtained data for a mosaic of the unlit face of the entire ring system near apoapsis. VIMS also performed a stellar calibration by staring at four stars.

Thursday, Jan. 10 (DOY 010):

The Optical Remote Sensing instrument teams and Science Planning have completed their analysis, and all have voted "NO-GO" for the Live Inertial Vector Propagator (IVP) update scheduled to occur on Jan. 13-18. The Radio Science (RSS) Saturn Occultation Live Moveable Block (LMB) update on DOY-015 will go forward as planned with the files to be uplinked on Saturday.

Friday, Jan. 11 (DOY 011):

The Cassini spacecraft's close flyby of Epimetheus in December 2007 returned detailed images of the moon's south polar region. The view shows what might be the remains of a large impact crater covering most of this face, and which could be responsible for the somewhat flattened shape of the southern part of Epimetheus seen previously at much lower resolution. For more details link to:

Monday, Jan. 14 (DOY 014):

Today is the third anniversary of the Huygens Probe entry and relay from Titan on Jan. 14, 2005.

The S36 sequence leads uplinked new CDA instrument flight software (FSW) version 12.0 today. A functional test is scheduled for Monday, Jan. 21, and will be followed by a FSW demonstration beginning Saturday, Jan. 26.

Over the weekend, Spacecraft Operations ran tests in the Integrated Test Laboratory (ITL) that had been requested by the S38 sequence leads for the Titan 41 and Enceladus 3 flybys. No faults were observed during the test and data analysis is now being performed by AACS and RADAR on the T41 data.

A command approval meeting was held today for eleven S37 Instrument Expanded Block files. Transmission of these files to the spacecraft will begin on Wednesday, Jan. 16. The window for uplink of the background sequence occurs on Saturday, Jan. 19.

The preliminary port occurred today for the S40 Science Operations Plan Update process. The files are being merged and reports will be sent out tomorrow for review by the teams. The official port is scheduled for Wednesday, Jan. 23.

Tuesday, Jan. 15 (DOY 015):

Non-targeted flybys occurred today of Methone and Pandora.

Orbit Trim Maneuver (OTM) #143 was performed today. This is the cleanup maneuver from the Titan 40 encounter on Jan. 5. The main engine burn began at 9:25 PM PST. Telemetry immediately after the maneuver showed the burn duration was 17.64 seconds, giving a delta-V of 2.88 m/s, as planned. All subsystems reported nominal performance after the maneuver. OTM-143 is the first maneuver using the new version of AACS flight software A8.7.6.

Today CIRS obtained a thermal measurement of the rings during an afternoon radial scan of the main rings and scanned the Cassini Division ring gap to study vertical dynamics. The Ion and Neutral Mass Spectrometer (INMS) and MIMI obtained data to study the composition and dynamics of Saturn's inner magnetosphere. VIMS, the Ultraviolet Imaging Spectrograph (UVIS), and CIRS observed Mimas and Tethys. RSS used Ka, X, and S band frequencies to observe the late inclined ingress ring occultation and both ingress and egress atmosphere occultation. The atmosphere occultation was observed by tracking the virtual image of Earth along Saturn's limb with the high gain antenna.

Wrap up:

Check out the Cassini web site at for the latest press releases and images.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. JPL designed, developed and assembled the Cassini orbiter.

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