Cassini Significant Events 06/17/09 - 06/23/09
The most recent spacecraft telemetry was acquired on June 23 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, June 17 (DOY 168)
Thanks to an accurate orbit estimation and execution for Orbit Trim
Maneuver (OTM) 201, delivery of the spacecraft to Titan for the T57 flyby
does not require further modification. Therefore OTM-202 has been
cancelled.
Monday, June 22 (DOY 173):
Today begins a week-long series of science meetings and project
status reports as part of the 48th Cassini Project Science Group
meeting.
The Target Working Team (TWT)/ Orbiter Science Team (OST) integrated
products for S56, covering orbits 123 through 125, from December 2009
through January 2010, were delivered today. The integrated products are
in their final form and no re-integration is planned. The next step in
sequence development, Science Operations Plan (SOP) implementation, will
kick off on July 8. Between now and then, the instrument teams will be
working on pointing designs for the sequence. TWT/OST teams deliver
integrated sequence products for the extended mission about every five
weeks.
Today Cassini passed Titan for the T57 flyby with closest approach at
approximately 12:52 PM PDT, traveling at 6 km/sec, an altitude of 955 km,
and latitude 42.2 degrees S. The Ion and Neutral Mass Spectrometer (INMS)
was prime at closest approach with an observation of the night side at
mid Southern latitudes. RADAR rode along with INMS using Synthetic
Aperture Radar (SAR), outbound altimetry, scatterometry, and radiometry.
The SAR runs parallel to tracks from T55 and T56 in the southern
hemisphere mapping sequence.
Radio Science (RSS) observed an ingress only occultation, which was a
unique opportunity that probed the highest northern latitude ever
expected for the Cassini mission, at about 79 degrees North. The
measurements will provide a profile of the electron number density of the
ionosphere and will help characterize variability in atmospheric
conditions such as temperature, pressure, extinction, turbulence, and
gravity waves as a function of latitude, in particular in the region of
the polar vortex. The characterization is a prime science objective of
these Radio Science occultations. This was the last Titan ionospheric and
atmospheric occultation in the Cassini Equinox Mission. The experiment
completed as planned with all data successfully acquired.
The Composite Infrared Spectrometer (CIRS) conducted mid-southern
latitude far and mid infrared vertical composition measurements. Imaging
Science had a 0.5-hour illuminated prime observation primarily for
photometry, then rode along with the Visual and Infrared Mapping
Spectrometer (VIMS) to observe Titan¹s trailing hemisphere at
mid-southern latitudes and relatively low phase angle, and with CIRS to
monitor clouds. On the inbound leg, the phase angle is much larger than
90 degrees and VIMS ride along observations provided information on
Titan¹s atmospheric composition. After closest approach, VIMS observed
the south polar region riding along with CIRS.
The Ultraviolet Imaging Spectrograph (UVIS) obtained an image cube of
Titan's atmosphere at extreme and far ultraviolet wavelengths. These
cubes provide spectral and spatial information on nitrogen emissions, H
emission and absorption, absorption by simple hydrocarbons, and the
scattering properties of haze aerosols. This is one of many such cubes
gathered over the course of the mission to provide latitude and seasonal
coverage of Titan's middle atmosphere and stratosphere.
The Radio and Plasma Wave Science instrument measured thermal plasmas in
Titan's ionosphere and surrounding environment, searched for lightning in
Titan's atmosphere, and investigated the interaction of Titan with
Saturn's magnetosphere.
------------------------
To unsubscribe from Cassini Spacecraft Updates or to subscribe with a
different email address, visit:
<
http://saturn.jpl.nasa.gov/news/mailinglistsignup/ >
------------------------
This email address is not monitored. For comments and questions, please
contact Cassini Outreach at:
<
http://saturn.jpl.nasa.gov/feedback/>
------------------------
Visit the JPL Cassini home page for more information about the Cassini
Project:
<http://saturn.jpl.nasa.gov/
>
------------------------
