Cassini Significant Events — 06/08/06 – 06/14/06

Cassini Significant Events -- 06/08/06 - 06/14/06

June 16, 2006

(Source: Cassini Project)

The most recent spacecraft telemetry was acquired Wednesday, June 14, from
the Goldstone tracking stations. The Cassini spacecraft is in an excellent
state of health and is operating normally. Information on the present
position and speed of the Cassini spacecraft may be found on the "Present
Position" web page located at
http://saturn.jpl.nasa.gov/operations/present-position.cfm .

Thursday, June 8 (159):

Science activities this week began on June 8, with an Ultraviolet Imaging
Spectrograph (UVIS) hunt for Saturn aurorae. This was followed by the
Cassini Plasma Spectrometer (CAPS) becoming "prime" and driving the
spacecraft orientation for the Magnetospheric and Plasma Science (MAPS)
instruments, pointing and rolling the spacecraft to study the structure and
dynamics of Saturn's magnetotail. Spacecraft control was then turned over
to the Imaging Science Subsystem (ISS) to observe transits of Saturnian
moons, followed by more MAPS magnetotail measurements. This pattern of
science events repeats until Sunday, June 18.

The Science Planning (SP) lead for S21 has completed the analysis for the
Live Inertial Vector Propagator (IVP) update for DOY 178-181. It has been
determined that all errors are well within the 2.4 mrad margin. As a result
of the SP recommendation, the sequence lead has decided to cancel the S21
Live Update.

The S23 Project Briefing was held today. After receiving management
approval, the final product was handed off to the sequence lead for the
start of the final development process next week. An outstanding issue for
S23 is the allocation of DSN passes from August 19 to September 20. The
STEREO launch and lunar flybys and Cassini are in contention for a number of
passes during this time frame. Both projects continue to work towards
resolution on this issue.

Friday, June 9 (DOY 160):

Cassini Outreach participated in a career day for 250 students at Kenter
Avenue Elementary School in Los Angeles, California.

Uplink Operations radiated the files for the Cosmic Dust Analyzer (CDA)
flight software checkout today. Registration on board has been confirmed.
The file will begin execution on 165T04:29:00.

The Titan Orbiter Science Team hosted a Titan15 to Titan18 preview meeting
today. After an overview of flyby geometries and the playback schedule, the
instrument teams presented their science objectives and measurement plan for
these flybys. The main emphasis this time around will be placed on MAPS.
Other items reported included what has been learned, and what will be done
in the future.

Cassini has made the cover of the July issue of Astronomy Magazine, and is
also featured in the July issue of Discover magazine with a nice ring
pictorial.

Monday, June 12 (DOY 163):

After examining the situation, Cassini scientists have agreed that an
attempt should not be made to recover science data from Titan 15 should an
outage occur during playback. The Mission and Science Planning teams
studied the specifics of the T15 high-value data recording and playback in
detail. The conclusion was that little high-value data recovery was
feasible via an after-the-fact response. The majority of the high-value data
will either be played back too late in a pass for a real-time response and
then overwritten shortly thereafter, or played back too early in a pass and
then overwritten too soon by real-time engineering and MAPS data.

Tuesday, June 13 (DOY 164):

All proposed science and engineering changes were submitted last Friday by
teams participating in the S26 Aftermarket process. An assessment package
was sent out today for the teams to review. It appears that all of the
requested changes can fit within available resources. Unless the
recommendations of the Target and Orbiter Science teams change, it is likely
that the decision meeting scheduled in two weeks can be canceled.

A kick-off meeting was held today for the final sequence development process
for S23. The leads stripped the sequence delivered to them last Friday by
Science Planning, and published the team subsequences - pieces - to the
project file repository. Any change requests for these files are due by
June 19, and the actual updated files are due by June 26.

Many individuals from the Cassini science teams are out of town this week
for the MAPS workshop being held at Imperial College in London, England.
The workshop begins today and concludes on Friday, June 16. Team meetings
for Ion and Neutral Mass Spectrometer, Magnetospheric Imaging Instrument,
and Magnetometer Subsystem will be held today and tomorrow. On Thursday
there will be a Titan workshop, and on Friday morning a workshop on
planetary rotation modulation phenomena, and in the afternoon, Saturn's
magnetosphere: plasma regions, boundaries, and transport.

Wednesday, June 14 (DOY 165):

The Spacecraft Operations Team and Navigation team hosted an Encounter
Strategy meeting for Titan 15-Titan 16 today. This meeting covered the
period of time from July 2 through July 22 and Orbit Trim Maneuvers (OTM)
65-67. A reminder was sent to participants that OTM-066 had already been
deleted by Navigation back on May 10, 2006.

A delivery coordination meeting was held today for the Spacecraft Operations
Office (SCO) Downlink/Uplink Coherency Tool or DUCT version 1.0. This is
the tool that will generate CDS commands to pause SSR playback at the
spacecraft coherency transition. Playback delay commands are needed to
prevent the permanent loss of science and engineering data due to a
telemetry gap when a coherency transition occurs. The tool was developed by
SCO when data loss "predicted" to be insignificant proved to be to be
otherwise, as recent science data returns from Titan observations have
shown. Additionally, development and formal testing of such a tool will
reduce the risk of errors being introduced with the current manual method of
avoiding this problem.