Solar Orbiter traces magnetic switchbacks in solar wind to the Sun

Researchers using the European Space Agency’s Solar Orbiter spacecraft have traced the origin of S-shaped kinks in the solar wind, known as ‘switchbacks’, back to the Sun. The study, published in Nature Astronomy, provides evidence that helps resolve debates regarding how these magnetic structures form.

By flying through a large switchback located halfway between Earth and the Sun, the spacecraft’s instruments sampled a specific mixture of charged oxygen and carbon particles. This chemical fingerprint suggests the material originated within hot magnetic loops near the Sun’s surface. This finding supports the ‘interchange reconnection’ theory, which occurs when magnetic field lines with different properties interact, causing them to snap open and release trapped plasma into space.

While the data points to reconnection as the primary formation process, scientists also noted signs of waves and turbulence, which likely influence the switchbacks after they have already moved away from the Sun.