Saturn's Gravitational Field, Internal Rotation, and Interior Structure

  title={Saturn's Gravitational Field, Internal Rotation, and Interior Structure},
  author={John David Anderson and Gerald Schubert},
  pages={1384 - 1387}
Saturn's internal rotation period is unknown, though it must be less than 10 hours, 39 minutes, and 22 seconds, as derived from magnetic field plus kilometric radiation data. By using the Cassini spacecraft's gravitational data, along with Pioneer and Voyager radio occultation and wind data, we obtain a rotation period of 10 hours, 32 minutes, and 35 ± 13 seconds. This more rapid spin implies slower equatorial wind speeds on Saturn than previously assumed, and the winds at higher latitudes flow… 
Saturn's Rings as a Seismograph to Probe Saturn's Internal Structure
As it has already done for Earth, the Sun, and the stars, seismology has the potential to radically change the way the interiors of giant planets are studied. In a sequence of events foreseen by only
Saturn's internal planetary magnetic field
A model of Saturn's internal planetary magnetic field based on data from the Cassini prime mission has been derived. In the absence of a determination of the rotation rate, the model is constrained
Discovery of a north‐south asymmetry in Saturn's radio rotation period
For many years it has been known that Saturn emits intense radio emissions at kilometer wavelengths and that this radiation is modulated by the rotation of the planet at a rate that varies by up to
Can Cassini magnetic field measurements be used to find the rotation period of Saturn's interior?
We investigate the determination of the rotation period of Saturn's interior using magnetic field measurements from Cassini. First, we vary the rotation period and search for the period that yields
The Structure of Planetary Period Oscillations in Saturn's Equatorial Magnetosphere: Results From the Cassini Mission
Saturn's magnetospheric magnetic field, planetary radio emissions, plasma populations, and magnetospheric structure are all known to be modulated at periods close to the assumed rotation period of
Interior Models of Saturn: Including the Uncertainties in Shape and Rotation
The accurate determination of Saturn's gravitational coefficients by Cassini could provide tighter constraints on Saturn's internal structure. Also, occultation measurements provide important
Models of Saturn's Interior Constructed with an Accelerated Concentric Maclaurin Spheroid Method
The Cassini spacecraft’s Grand Finale orbits provided a unique opportunity to probe Saturn’s gravity field and interior structure. Doppler measurements yielded unexpectedly large values for the
Saturn's Deep Atmospheric Flows Revealed by the Cassini Grand Finale Gravity Measurements
How deep do Saturn's zonal winds penetrate below the cloud level has been a decades‐long question, with important implications not only for the atmospheric dynamics but also for the interior density
Saturn’s magnetic field revealed by the Cassini Grand Finale
The Grand Finale phase of the Cassini mission took the spacecraft through the gap between Saturn's atmosphere and the inner edge of its innermost ring 22 times, ending with a final plunge into the atmosphere on 15 September 2017, and offered an opportunity to investigate Saturn’s internal magnetic field and the electromagnetic environment between the planet and its rings.


Voyager measurement of the rotation period of Saturn's magnetic field
We determine Saturn's radio rotation period using measurements made by the Planetary Radio Astronomy experiment onboard the Voyager spacecraft. The sidereal period deduced is 10 hr 39 min 24 sec ±7
The Variable Rotation Period of the Inner Region of Saturn's Plasma Disk
We show that the plasma and magnetic fields in the inner region of Saturn's plasma disk rotate in synchronism with the time-variable modulation period of Saturn's kilometric radio emission. This
A regular period for Saturn's magnetic field that may track its internal rotation
The rotation rate of a planet is one of its fundamental properties. Saturn's rotation, however, is difficult to determine because there is no solid surface from which to time it, and the alternative
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A new constraint on Saturn's zonal gravity harmonics from Voyager observations of an eccentric ringlet
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Structure of the Jovian envelope from Pioneer 10 gravity data
Measurement of Jupiter's zonal harmonics J2 and J4 by the celestial mechanics experiment on Pioneer 10 may be used to obtain a constraint on the structure of the outer envelope of Jupiter, using an
Looking into the Giant Planets
In his Perspective, Fortney highlights recent model studies that have shed light on the likely structure and evolution of these giant planets, and highlights the need for accurate computer simulations and laboratory data on hydrogen under high pressure.
Models and theoretical spectrum for the free oscillations of Saturn
We constructed new models of Saturn with an allowance made for a helium mass fraction of ∼0.18–0.25 in its atmosphere. Our modeling shows that the composition of Saturn differs markedly from the