Observations of Kolmogorov Turbulence in Saturn's Magnetosphere

The Kolmogorov scaling in the inertial range of scales is a distinct characteristic of fully developed turbulence, and studying it offers valuable insights into the evolution of turbulence. In this work, we perform a statistical survey of the power spectra with the Kolmogorov scaling in Saturn's magnetosphere using Cassini measurements. Two cases study show that both magnetic-field and electron density spectra exhibit f ^−5/3 at the MHD scales. The statistical analysis reveals a wide-ranging and abundant presence of Kolmogorov spectra throughout magnetosphere, observed across all local times. Interestingly, the occurrence rate of these Kolmogorov-like events within Saturn's magnetosphere surpasses that observed in the planetary magnetosheath. The measurements of magnetic compressibility for the Kolmogorov-like events show the dominance of incompressible Alfvénic turbulence (44.64%) with respect to magnetosonic-like one (6.94%). In addition, the source and evolution of the turbulent fluctuations are further discussed.