Cassini Significant Events 07/10/2013 – 07/16/2013

Cassini is orbiting Saturn with a 16-day period in a plane inclined 56.7 degrees from the planet's equatorial plane. The most recent spacecraft tracking and telemetry data were obtained on July 17 using two 34-meter diameter Deep Space Network stations at Goldstone, California. Except for some science instrument issues described in previous reports (for more information search the Cassini website for CAPS and USO), the spacecraft continues to be in an excellent state of health with all of its subsystems operating normally. Information on the present position of the Cassini spacecraft may be found on the "Present Position" page at: http://saturn.jpl.nasa.gov/mission/presentposition/.

The Titan T-92 encounter on Wednesday was the highlight of this week's activities in Saturn orbit. During this encounter Cassini rotated about all three axes to point its telescopes and conduct multiple pre-planned science observations. The Radar instrument employed its various sensing modes including high-resolution synthetic-aperture imaging of the northern surface, which is obscured by the atmosphere in the visible-light part of the spectrum. Data from the encounter were recorded on-board, and during the rest of the week in between other activities, they were telemetered successfully across interplanetary space and captured by the Deep Space Network stations on three continents. More detail may be found on the T-92 page: http://saturn.jpl.nasa.gov/mission/flybys/titan20130710. Although it’s properly in next week’s report, the opportunity to "Wave at Saturn" during Earth imaging will occur on Friday, July 19 at 2:27 pm PDT. For more information see: /news/12768/jplers-wave-at-saturn-as-part-of-worldwide-campaign/

Wednesday, July 10 (DOY 191)

With typical accuracy, the flight team navigated Cassini well within one kilometer of its targeted 964.0 kilometer Titan flyby altitude today, going some 21,240 kilometers per hour with respect to the gigantic moon. Gravitational interaction and Titan's momentum decreased the inclination of Cassini's orbit precisely according to plan, going from 59.4 degrees off Saturn's equatorial plane down to 56.7 degrees. The T-92 encounter also increased Cassini's orbital period from 12 to 16 days. Subsequent Titan flybys will continue adjusting the spacecraft's inclination until early next year when T-110 brings it down to within a degree of Saturn's equatorial plane again.

Thursday, July 11 (DOY 192)

Today and again on Friday the Imaging Science Subsystem (ISS) continued imaging Titan while speeding outbound, with the Visible and Infrared Mapping Spectrometer (VIMS) taking data as well. These observations monitored Titan's high southern latitudes, where winter is approaching, to track clouds and their evolution for an extra day after closest approach.

Friday, July 12 (DOY 193)

Work proceeded on the command sequence S80, which will be uplinked to the flight system on Aug. 9, and will begin executing on Aug. 14. Commands for S81, S82, and S83 are also in the mill.

Saturday, July 13 (DOY 194)

The Ultraviolet Imaging Spectrograph (UVIS) performed a series of long-duration observations of Saturn in the extreme-ultraviolet (EUV) and the far-ultraviolet (FUV) parts of the spectrum, each a slow scan across Saturn's illuminated hemisphere to form spectral images. ISS rode along to take one polarimetry measurement during each scan using its wide-angle camera, while VIMS and the Composite Infrared Spectrometer (CIRS) also took data. After the first UVIS scan, VIMS made some mosaics to form a Saturn south-regional map.

Sunday, July 14 (DOY 195)

Via a "mini-sequence," the flight team commanded Cassini to turn and fire its main rocket engine for 1.4 seconds. This Orbit Trim Maneuver #353 imparted a change in velocity of 243 millimeters per second, cleaning up the trajectory following T-92. Next, ISS made an observation in the Titan monitoring campaign, then UVIS and VIMS made observations of Saturn similar to the ones they made on Saturday.

Monday, July 15 (DOY 196)

Early today Cassini coasted through apoapsis about 1.5 million kilometers "up" from Saturn, slowing to 15,690 kilometers per hour relative to the planet. This marked the start of the spacecraft's orbit #195.

UVIS repeated its Saturn EUV and FUV observations, but shortened them so VIMS could spend as much time as possible observing an occultation as the garnet-red star Mu Cephei passed behind the ring system.

The crisp, clear shadows of Saturn's rings on the southern atmosphere make a fine study, with the rings themselves also visible, in an image featured today: /resources/15850

Tuesday, July 16 (DOY 197)
Science activities concluded for the week with another UVIS EUV and FUV observation of Saturn, with ISS, CIRS and VIMS again taking data.