NASA Cassini Significant Events 07/25/2012 – 07/31/2012
The most recent spacecraft tracking and telemetry data were collected on July 31 by the Deep Space Network’s 70 meter Station 63 at Madrid, Spain. Except for the Cassini Plasma Spectrometer, which is off, and the inoperative Ultrastable Oscillator, the Cassini spacecraft is in an excellent state of health with all its subsystems functioning 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-85 flyby executed normally yesterday. All of the radiometric tracking data and telemetry data were successfully collected without any loss. The spacecraft was so close to its nominal trajectory that the Cassini Navigation team was able to cancel the “cleanup” Orbit Trim Maneuver (OTM), which was planned for three days past the encounter. More information on T-85 is available here: http://saturn.jpl.nasa.gov/mission/flybys/titan20120724/
Wednesday, July 25 (DOY 207)
With Titan 177,000 kilometers away and receding, medium resolution capability was available for the Visible and Infrared Mapping Spectrometer (VIMS) to detect clouds and monitor post-equinox climatic changes. The Imaging Science Subsystem (ISS) and Composite Infrared Spectrometer (CIRS) observed Titan’s atmosphere, riding along while VIMS controlled spacecraft pointing.
Thursday, July 26 (DOY 208)
The Ultraviolet Imaging Spectrograph (UVIS) performed a 17 hour system scan of Saturn’s magnetosphere in order to image hydrogen and oxygen.
Friday, July 27 (DOY 209)
The Magnetometer (MAG) performed an 8 hour calibration while rotating the spacecraft about its X-axis.
Saturday, July 28 (DOY 210)
Today and the next twelve days are dedicated to UVIS system scans to image magnetospheric hydrogen and oxygen.
Sunday, July 29 (DOY 211)
A DSN track completed early today. This was one of six this week to carry out two-way digital data communications with Cassini, while making high-precision measurements of the incoming signal’s Doppler shift for radial speed information, and the two-way light time to determine distance. Today it was Station 45, a 34 meter diameter “X-band high-efficiency” antenna at the Canberra Deep Space Communications Complex near Canberra, Australia.
Monday, July 30 (DOY 212)
An image titled “Peeping Mimas” was featured today, showing the small icy moon rising over the limb of the much larger moon Dione. http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=4603
Tuesday, July 31 (DOY 213)
The Attitude and Articulation Control Subsystem (AACS) team updated a parameter in the spacecraft’s AACS Flight Computer that affects main engine performance. The commands, which were approved for uplink this morning, first read out the memory location, made the change, and then read it out again. The change was confirmed 2 hours 46 minutes later. The new value will come into play during the main engine burn for OTM-330 on August 7.
