Cassini Significant Events 12/16/09 – 12/22/09

The most recent spacecraft telemetry was acquired on Dec. 22 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/operations/present-position.cfm.

Wednesday, Dec. 16 (DOY 350)

S56 sequence leads uplinked instrument expanded block files to the spacecraft today. Eight files were sent supporting Imaging Science (ISS), the Visual and Infrared Mapping Spectrometer (VIMS), Composite Infrared Spectrometer (CIRS), Ion and Neutral Mass Spectrometer (INMS), Cassini Plasma Spectrometer (CAPS), and Ultraviolet Imaging Spectrograph (UVIS). The sequence approval meeting will be held tomorrow and uplink of the background sequence will occur later in the week. Following the approval meeting, the Radio Science (RSS) DOY 359 Live Movable Block kick-off meeting will be held.

Thursday, Dec. 17 (DOY 351)

In a news release today it was announced that Cassini has captured the first flash of sunlight reflected off a lake on Saturn's moon Titan, providing definite confirmation of the presence of liquid on the part of the moon dotted with many large, lake-shaped basins. For full details link to: http://saturn.jpl.nasa.gov/news/newsreleases/newsrelease20091217/ .

Caltech Press Release - Caltech Scientists Discover Fog on Titan Saturn's largest moon, Titan, looks to be the only place in the solar system - aside from Earth - with copious quantities of liquid on its surface. According to planetary astronomers, Earth and Titan share yet another feature, which is inextricably linked with that surface liquid: common fog.
For more information link to: http://www.caltech.edu/news/caltech-scientists-discover-fog-titan-1586 .

Friday, Dec. 18 (DOY 352)

Based on analysis by ISS and RSS, there are insignificant differences between the current orbit determination (OD) solution incorporated into the "on the shelf" products for the DOY 359 RSS Live Movable Block, and the newly released OD solution. Because of this, Uplink Operations will cancel the "Go-No Go" meeting scheduled for Monday morning and uplink the pre-built products on Dec. 23.
The S56 background sequence was radiated to the spacecraft today. Uplink Operations has confirmed that the sequence is on board and correctly registered.

Sunday, Dec. 20 (DOY 354)

Orbit Trim Maneuver (OTM) #228 was performed today. This was the apoapsis maneuver setting up for the Titan 64 encounter on Dec. 27. The main engine burn began at 12:00 AM PST. Telemetry immediately after the maneuver showed a burn duration of 13.065 seconds, giving a delta-V of 2.218 m/s. All subsystems reported nominal performance after the maneuver.

Monday, Dec. 21 (DOY 355)

UVIS performed Saturn system scans to observe atomic oxygen and hydrogen, mosaic scans of the Saturn magnetosphere, and a stellar calibration of the instrument. Magnetospheric and Plasma Science (MAPS) instruments performed dawn-side magnetospheric boundary observations, participated in the solar wind aurora campaign to observe the auroral magnetosphere and the Saturn kilometric radiation source regions, and observed the dawn-side magnetospheric boundary. Orbit 123 began on DOY 352 with Cassini at an apoapse distance of 37.96 Rs, an inclination angle of 4.9 degrees, and a 104-degree phase angle. The final observation of the sequence found CIRS undertaking a 23-hour mid-infrared mapping of Saturn to determine the upper troposphere and tropopause temperatures at different latitudes and longitudes.

Tuesday, Dec. 22 (DOY 356)

The S55 sequence concluded and S56 began execution today at 356T00:44:00 PST. The sequence will run for 32 days and conclude on Jan. 23, 2010. During that time there will be two targeted encounters of Titan and six non-targeted flybys – one each of Tethys, Prometheus, Pandora, Methone, Enceladus, and Calypso. Six maneuvers are scheduled, numbered 229 through 234.

An encounter strategy meeting was held today to cover the period between Dec. 28 and Jan. 12, 2010, Titan flybys T64 and T65, and maneuvers 230-232.