Year: 2019
Type: article
Abstract: Seismology of the gas giants holds the potential to resolve long-standing questions about their internal structure and rotation state. We construct a family of Saturn interior models constrained by the gravity field and compute their adiabatic mode eigenfrequencies and corresponding Lindblad and vertical resonances in Saturn’s C ring, where more than 20 waves with pattern speeds faster than the ring mean motion have been detected and characterized using high-resolution Cassini Visual and Infrared Mapping Spectrometer stellar occultation data. We present identifications of the fundamental modes of Saturn that appear to be the origin of these observed ring waves, and we use their observed pattern speeds and azimuthal wavenumbers to estimate the bulk rotation period of Saturn’s interior to be (median and 5%/95% quantiles), significantly faster than Voyager and Cassini measurements of periods in Saturn’s kilometric radiation, the traditional proxy for Saturn’s bulk rotation period. The global fit does not exhibit any clear systematics indicating strong differential rotation in Saturn’s outer envelope.
Source: The Astrophysical Journal
Authors: Christopher Mankovich, Mark S. Marley, Jonathan J. Fortney, Naor Movshovitz
Institutions: University of California, Santa Cruz, Ames Research Center
Language: English
Topic: Astro and Planetary Science
Subfield: Space and Planetary Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: bronze
Awards: NASA'S CASSINI MISSION HAS AND WILL CONTINUE TO MAKE OBSERVATIONS WHICH TRANSFORM OUR KNOWLEDGE OF SATURN'S INTERIOR. PAIRED WITH APPROPRIATE THEORE, MRI: Acquisition of a High-Performance Parallel Computing Cluster for Astrophysics Research at the University of California, Santa Cruz, OBJECTIVES WE AIM TO UNDERSTAND THE INTERIOR OF SATURN THROUGH A COMBINATION OF NEW GRAVITY FIELD DATA FROM CASSINI, NEW AB INITIO SIMULATIONS OF PLA
OpenAlex ID: W2804458406