Chaotic fluctuations within the early solar wind

A wide range of magnetic field fluctuations in the solar wind have been comprehensively studied over decades, but none of those studies have observed chaotic fluctuations within the solar wind. We present here the observations of chaotic magnetic field fluctuations within the solar wind. In this study we quantify high resolution electron scale magnetic field fluctuations with information theoretic measures (Shannon entropy + Jensen-Shannon complexity). Jensen-Shannon complexity maps of time series data provide a mathematical tool that can characterize fluctuations as stochastic, chaotic, or periodic phenomena. We apply this recently developed tool to characterize the Parker Solar Probe high temporal resolution fluxgate magnetometer magnetic field fluctuations (292.9 samples/s or 3.413 ms per sample) at perihelion. We find that these fluctuations are either chaotic or chaotic with a strong noise component in one or more magnetic field components. Limited statistics of the perihelion periods indicate that at the more distant perihelia (∼0.17 AU) have chaotic fluctuations within just the normal component of the magnetic field and the closer perihelia (∼0.05 AU) display chaotic fluctuations within all three components of the magnetic field. Finally, we find that the chaotic fluctuations appear to be of high dimensionality. · We apply for the first time the Jensen-Shannon complexity technique to Parker Solar Probe fluxgate magnetometer data at perihelion. · High temporal resolution magnetic field fluctuations within 0.17 solar radii can be chaotic or chaotic with a strong noise component. · Chaotic fluctuations were generally observed for frequencies above about 10 Hz up to 293 Hz, above the proton gyrofrequency (1-10 Hz).