General Properties of the Magnetosheath: The MMS Unbiased Campaign

The Magnetospheric Multiscale (MMS) mission's extended phase introduced an “unbiased campaign” that provided the first high-resolution data set of the terrestrial magnetosheath obtained without human selection, across complete crossings from the bow shock to the magnetopause. This is achieved by collecting 3 min of burst-mode data every 9 min. Leveraging this novel data set, we report average plasma parameters and observe the emergence of a (Formula presented.) range in the magnetic field power spectrum. A distinct ordering of both bulk and turbulence quantities is demonstrated when the Alfvénic Mach number is used as a proxy for the distance from the bow shock. This ordering enables us to obtain clear insights into the occurrence of small-scale current sheets throughout the magnetosheath by evaluating magnetic field kurtosis. Furthermore, the evolution of the correlation time is opposite to that of kurtosis and aligns with the principle of turbulence relaxation. This information is dispersed when quantities are sorted by geocentric distance. Crucially, striking differences emerge in turbulence-related quantities when comparing unsupervised and supervised data sets. These findings provide valuable insights into magnetospheric turbulence, establishing the campaign as a critical resource for unbiased statistical analysis of this environment.