The most recent spacecraft telemetry was acquired on April 20th from the Deep Space Network tracking complex at Goldstone, California. 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/mission/presentposition/
Wednesday, April 14 (DOY 104)
All teams submitted Port 1 Spacecraft Activity Sequence Files today as part of the Science Operations Plan process for S63. The files will be merged and sent back out to the teams for review.
Thursday, April 15 (DOY 105)
This week the Composite Infrared Spectrometer took several compositional sit and stare observations of Saturn to measure oxygen compounds in the stratosphere as a function of latitude and performed an exercise to quantify the effects of ring particle impacts on the mirror performance by monitoring scattered infrared solar radiation as a function of offset angle from the sun. The Magnetospheric and Plasma Science instruments took measurements as part of the solar wind aurora campaign to observe the acceleration region of the magnetosphere and the Saturn kilometric radiation source regions. Radio Science performed an Ultra Stable Oscillator characterization and periodic instrument maintenance. Imaging Science observed the Saturnian satellites Albiorix and Bebhionn, obtained low resolution, low elevation, high-phase images of the E ring, and took images of the transit of Titan across Dione for orbit determination purposes.
Sunday, April 18 (DOY 108)
Orbit Trim Maneuver (OTM) #243 was performed today. This was an apoapsis maneuver setting up for the Enceladus 9 encounter on Apr. 28 (Apr. 27 in PDT). The Reaction Control Subsystem burn began at 6:44 AM PDT. Telemetry immediately after the maneuver showed a burn duration of 38.25 seconds, giving a delta-V of 44.56 mm/s. All subsystems reported nominal performance after the maneuver.
Monday, April 19 (DOY 109)
Members of the Saturn Observation Campaign reported this week that Apr. 24 is International Astronomy Day and Saturn will be prominently visible below the moon and Mars. Contact your closest Saturn Observation Campaign volunteer for Saturn viewing opportunities here:
Tuesday, April 20 (DOY 110)
The Cassini Program made it into the news this week in a New York Times article: A Saturn Spectacular, With Gravity's Help:
The Cassini Science League has posted a report on the effects of ring shadow on the atmosphere of Saturn. Saturn's atmosphere is affected by seasonal changes just like Earth's is, but perhaps even more so, because the poles spend nearly 15 Earth-years in winter darkness and the next 15 years in sunlight. On top of that, the cooling shadow of the rings causes differences in heating and sunlight-driven chemistry between the shaded and sunlit parts of Saturn's atmosphere.