Cassini Significant Events
24 Mar 2009
Cassini Significant Events for 03/18/09 - 03/24/09
The most recent spacecraft telemetry was acquired on Mar. 24 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
Wednesday, March 18 (DOY 077)
The S48 background sequence was reactivated late last night at
2009-076T20:04:48 PDT. The only remaining activities to complete the
thruster swap to the B branch are the execution of two spacecraft
engineering activities originally scheduled for the time when the
background sequence was deactivated.
Because the first Live Update Block (LUB) in S49 occurs within 24
hours of the start of sequence execution, the kickoff meeting was
held today during S48. Teams will have the weekend to analyze the
data and the Go/No Go meeting will be held on Monday.
An encounter strategy meeting was held today to cover the period
between Mar. 27 and Apr. 4, Titan flybys T51 and T52, and OTM 186.
Thursday, March 19 (DOY 078):
Files for the final input port in the Science Operations Plan process
for S51 were due today.
Friday, March 20 (DOY 079):
The final sequence approval meeting for S49 was held today. The
background sequence will go up to the spacecraft Sunday night, and
the sequence will begin execution on Thursday, Mar. 26.
A non-targeted flyby of Titan occurred today.
Cassini Outreach presented a Cassini Mission Roundup and
International Year of Astronomy talk at the Thousand Oaks, CA,
Discovery Center's Super Science Sunday on Mar. 22. Over 1000
science enthusiasts of all ages visited hands-on science activities,
heard several speakers, viewed Cassini images, received Cassini
outreach materials, and viewed the planet Saturn as they were leaving.
On Saturday, Imaging Science continued Titan cloud monitoring
observations begun the day before, the Cosmic Dust Analyzer was prime
for a ring plane crossing, the plumes of Enceladus were observed in
order to study their phase function, and the Composite Infrared
Spectrometer (CIRS) performed a ring vertical temperature scan, this
time from the opposite side of the ring plane than has been observed
On Sunday another Titan monitoring observation executed which
provided isolated snapshots. This type of observation is intended to
improve understanding of how often there are clouds on Titan, where
they are appearing as the seasons change, how fast and in what
direction the winds blow, and also how the haze evolves with the
seasons. Another CIRS vertical temperature scan of the rings at a
different location and a Visual and Infrared Mapping Spectrometer
ring stellar occultation followed this.
Monday, March 23 (DOY 082):
Because of the deactivation of the background sequence to support the
thruster branch swap, the Spacecraft Periodic Engineering Maintenance
activity scheduled for that time frame was canceled. The activity
was converted to a series of real time commands and uplinked to the
spacecraft last week for execution today.
Tuesday, March 24 (DOY 083):
Due to the excellent accuracy of Orbit Trim Maneuver (OTM) 183x last
week, the first on the B-Branch thrusters, there is only a small
shift in the predicted flyby point for the Titan 51 encounter
relative to the planned target. In addition there are virtually no
differences with respect to Optical Remote Sensing Instrument
pointing for the remaining activities in S48 if OTM-184 is performed
or canceled. As a result, OTM-184 has been cancelled.
Today the Spacecraft Office held an Engineering Activities Review for S54.
New flyover maps of Titan show the 3-D topography and height of the
1,200-meter mountain tops, the north polar lake country, the vast
dunes more than 100 meters high that crisscross the moon, and the
thick flows that may have oozed from possible ice volcanoes. The
topographic maps were made from stereo pairs of radar images. For
the full release and two animated flyovers, link to:
Visit the JPL Cassini home page for more information about the
Cassini Project: http://saturn.jpl.nasa.gov/