Turbulence Evolution Between 0.5 and 1 AU for the Solar Wind of Various Origins

Probing the solar wind at different distances from the Sun provides a great opportunity to explore turbulence development in the unlimited space. Recent measurements from the near-Sun plasma demonstrate the evolution of turbulence from an undeveloped to a fully developed state on the path from the Sun to the Earth. On the other hand, the properties of turbulence are known to be altered for the solar-wind streams of different origin. The present study adopts measurements during two Solar Orbiter and Wind alignments with separations of 0.1 and 0.5 AU to analyze changes in the properties of turbulence for the same plasma parcels embedded in the solar-wind streams of various origins. The results demonstrate that at scales spectra become shallower toward the Earth’s orbit, while Kolmogorov scaling stays unchanged at the MHD scales. The power of the fluctuations within the inertial range is shown to be an important factor that determines the evolution of the turbulent fluctuations in the inner heliosphere, regardless of the origin of the solar-wind stream.