For the radio science instrument, the radio signals from Cassini were transmitted to the NASA Deep Space Network complexes in Australia, Spain and the U.S.
See
Volume 1-Mission Overview, Science Objectives and Results for full science report. The technical report is in other volumes archived at the Jet Propulsion Lab.
Mission Science Highlights and Science Objectives Assessment provides a brief overview of the mission
About RSS
The Radio Science Subsystem was used to probe the Saturn system at radio frequencies. Unlike the other science instruments onboard the Cassini spacecraft, the radio science experiment included not just components scattered around the spacecraft but the large, Earth-based radio antennae of the Deep Space Network that received the signals transmitted by RSS as well. RSS utilized Cassini's high-gain antenna to transmit signals to the ground at one of three radio frequencies and to receive signals produced by the DSN. Its primary functions were to observe occultations and probe the gravity fields of bodies in the Saturn system. Assembled at the Jet Propulsion Laboratory, RSS incorporated parts supplied by JPL, NASA's Lewis Research Center, the John Hopkins University Applied Physics Laboratory, Italy's Agenzia Spaziale Italiana and other subcontractors. Science objectives for RSS include:
- determining the gravity fields of the larger bodies in the Saturn system, including Titan, the large, icy satellites and Saturn itself,
- probing Saturn's rings at centimeter wavelengths using occultation experiments to constrain their structure and the physical properties,
- characterizing the non-axisymmetric structures in Saturn's rings, such as the bending and density waves and equatorial and inclined ringlets within the system
- and investigating the vertical profiles of the atmospheres and ionospheres of Saturn and Titan through occultation observations.
Cassini's radio science experiment probed the Saturn system by transmitting radio signals at three distinct wavelengths: S-band (2.3 GHz), X-band (8.4 GHz) and Ka-band (32 GHz). For much of the Cassini mission, RSS was capable of operating in one of two distinct modes. Two-way measurements involved the DSN stations generating a single uplink carrier signal at either X-band (~7.4 GHz) or Ka-band (~34 GHz), with the actual transmission frequencies being adjustable in order to compensate, for example, for the Doppler effect between the Earth and the Cassini orbiter. The high-gain antenna would receive this uplink signal, transforming it to one of three signals (2.3 GHz, 8.4 GHz or 32 GHz) coherent with the uplink signal and returning an amplified signal to Earth which was recorded at the DSN. A variant of this two-way mode, referred to as three-way mode, involved the downlink signal being recorded on Earth through a different DSN antenna than the one generating the uplink signal. The second mode available to RSS was called one-way mode, which utilized the instrument's ultrastable oscillator to generate S-band, X-band or Ka-band signals with exceptional short-term phase and frequency stability. However, with the loss of the USO in late 2011, RSS was restricted to using two-way (three-way) mode for the remainder of the mission.
The engineering details of the RSS instrument and the science objectives it was built to address are described in further detail in the
Space Science Reviews paper by
Kliore et al. (2004).
Finding RSS Data
Search-for and Filter Raw Data
The
Event Calendar is one way to find data associated with particular events such as auroral observations.
See the
Master Schedule for a time ordered listing of observations by all instruments. This may help find data based on particular events, although the OPUS tool linked above will be much simpler to use in most circumstances.
In the following Cassini Radio Science bundles the primary data are the Radio Science Receiver (RSR) files, the Orbit Data Files (ODFs), and the Tracking and Navigation Files (TNFs). The primary data files are accompanied by supplementary data files. These include 0158-Monitor (158) files, C-Kernel (CKF) files, Earth Orientation Parameters (EOP) files, Ionosphere Calibration (ION) files, Path Delay (PD1 and PD2) files, Spacecraft/Planetary Ephemeris (SPK) files, Telemetry (TLM) files, and Troposphere Calibration (TRO) files. The bundle is a migration of data from the original PDS3 archive with minor improvements and corrections.
Icy Satellites Bundle (SSA)
The cassini-rss-raw-ssa bundle contains the Cassini radio science raw data acquired during Cassini icy satellite gravity science observations and a single file of Enceladus occultation data.
See data_odf table-of-contents and planning goals.
Log of data-tnf
Log of data-rsr01
Data-rsr08 contains Iapetus data and rsr16 contains Enceladus date
Cassini RSS Planning Tables
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A., 2025, cassini-rss-raw-ssa,
http://www.doi.org/10.17189/gtth-k529
Saturn Gravity Science Experiment Bundle (SAGR)
The cassini-rss-raw-sagr bundle contains the Cassini radio science raw data acquired during the Saturn Gravity Science Experiment (SAGR)
See
Table of Contents of ODF
Cassini RSS Planning Tables
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A., 2025, cassini-rss-raw-ssa,
http://www.doi.org/10.17189/ec4s-6p49
Saturn and Saturn Ring Occultation Bundle (SROC)
This bundle contains the Cassini radio science raw data acquired during the Saturn and Saturn/Ring gravity
and Occultation Experiment (SROC).
See
Table of Contents of ODF
Cassini RSS Planning Tables
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A., 2025, cassini-rss-raw-sroc,
http://www.doi.org/10.17189/5azd-js41
Titan Gravity, Occultations and Bistatic Bundle (Titan)
This bundle contains the Cassini radio science raw data acquired during Titan gravity, occultation, and bistatic radar experiments.
See
Table of Contents of ODF
Cassini RSS Planning Tables
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A., 2025, cassini-rss-raw-sroc,
http://www.doi.org/10.17189/vbdg-1t35
Gravitational Wave Experiment
This bundle contains raw radio science data acquired during the Cassini Gravitational Wave Experiment (GWE).
See
Table of Contents of ODF
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A.,2025, cassini-rss-raw-gwe,
http://www.doi.org/10.17189/6cyf-h386
Solar Conjunction Experiment
See
Table of Contents of ODF
Refer to
User’s Guide to plan an approach to analysis of RSS data.
Citing the Data
PDS recommendations for citing data sets can be found
here.
Verma, A. K.; Barbinis, E.; Goltz, G. L.; Kliore, A. J.; Simpson, R. A., 2025, cassini-rss-raw-sce,
http://www.doi.org/10.17189/p2fa-qk29
Processed Data Products
Selecting Data Products
Analyzing RSS Data
Once data products have been selected and retrieved, users will need appropriate software to read, manipulate and display that data. Below are listed software packages that will enable users to make use of RSS data.
End-to-end diffraction reconstruction of a complete event can be done with this
open source software
PDS: The Planetary Atmospheres Node
