This still is from an
interactive 3D model that includes information on Cassini
and all of its instruments.
Spacecraft Noise Sources
Certain spacecraft events affected how Cassini gathered science data.
For example, many of these events generated noise that affected the
ability of the instruments on the spacecraft to properly collect science data.
In addition, other events required that some of the instruments be
turned off for the duration of the event. Finally, a third set of events, such as
a change in the mass of the spacecraft, impacts data analysis. Below
are the various noise sources and spacecraft events that have bearing on
finding and analyzing science data.
The orientation of the magnetometer sensors with respect to the
spacecraft may change slightly after events such as spacecraft
maneuvers or as the thermal environment changes with distance from
the sun. The SCAS is a means of determining the magnetometer
sensor alignment.
See the
README
for more information.
This deliberate electromagnetic signal may interfere with other
science observations. Specifically, CDA may misinterpret a sounder
pulse as a dust detection.
See the
README
for more information.
See the
README
for more information.
Spacecraft Configuration Information
See the
README for more
information.
See the
README
for more information.
There were 97.5 cover cycles during flight.
See the
README
for more information.
See the
README
for more information.
See the
README
for more information.
Navigation Information
This is the Doppler and range data used by the navigation team to determine Cassini’s orbit. TDM’s are text files formatted according to international standards.
This file describes a rotation from an Earth-fixed
reference frame to an inertial reference frame. It is used to convert tracking station
locations (Earth-fixed coordinates) into the 'radio' frame (inertial coordinates) needed
to process Doppler and range measurements.
These files contain troposphere and ionosphere calibrations used to
model the effect of Earth's atmosphere on Doppler and range measurements. They span
Cassini's tour phase.
This file describes clock differences between DSN
complexes during times when '3-way' Doppler tracking is acquired. It is used to calibrate
Doppler measurements uplinked from one DSN complex and received at a different
complex. The file also contains a few corrections to range measurements. In these
instances, the file contains adjustments for range calibrations that were incorrectly
reported on the Doppler and range tracking data file. The file spans Cassini's tour phase.
This file contains a list of propulsive events required for attitude
and articulation control management. It includes the time of the events and predicted
delta-V's imparted to the spacecraft. It spans Cassini's tour phase.
This file contains a listing of all the trajectory correction and orbit trim
maneuvers performed by Cassini. It provides maneuver times and delta-V magnitudes.
Gap Report
Many tables provided on this site are "as-planned", meaning that they represent the initial science-planning time tables. For various reasons,
data might not be delivered even though an observation was planned. For example, weather conditions at the Deep Space Network may have
blocked communications during downlink, and data would therefore be lost. The gap reports below describe these time periods when data was
either not gathered or was lost. If an observation that you are expecting to find has "gone missing", this can help explain the reason why.