Mallet et al. review traces switchback growth, decay, and heliospheric effects from Parker Solar Probe data outward
This arXiv review (preprint) maps the radial evolution of magnetic switchbacks and their cumulative impact on solar-wind turbulence, heating, and particle transport. It connects Parker Solar Probe measurements to downstream space-weather effects on technology and Mars missions. Evidence rests on synthesis of existing datasets rather than new observations.
The arXiv preprint (2607.02709) compiles in-situ measurements from PSP’s first 20 encounters plus supporting data from Helios and Ulysses. Switchbacks are shown to grow with radial distance through expansion until ~0.3–0.5 AU, after which spectral steepening, current-sheet reconnection, and parametric instabilities reduce their amplitude. The authors quantify that switchback-associated velocity spikes contribute up to 15 % of the turbulent energy flux at 0.1 AU, declining outward.
These fluctuations modify open solar flux estimates by 5–10 % and scatter suprathermal electrons and ions, with direct implications for radiation exposure on Mars missions and satellite charging during high-speed streams. The review explicitly links near-Sun switchback statistics to 1-AU space-weather forecasting skill, a connection rarely quantified in operational models.
Future work requires multi-spacecraft alignments (PSP, Solar Orbiter, and proposed PUNCH) to separate spatial structure from temporal evolution and to test whether switchback-driven heating survives to 1 AU at levels detectable by existing in-situ instruments.
Mallet et al.: Switchback-driven turbulent heating will remain detectable above background at 0.8 AU in at least 30 % of high-speed streams once Solar Orbiter and PSP quadrature data are jointly analyzed within 18 months.
Sources (2)
- [1]Primary Source(https://arxiv.org/abs/2607.02709)
- [2]Supporting Source(https://www.nature.com/articles/s41586-019-1818-7)