Solar Orbiter traces the origin of magnetic switchbacks in the solar wind to interchange reconnection at the Sun

8 October 2026

The European Space Agency reported that its Solar Orbiter spacecraft has traced a magnetic switchback back to its source on the Sun. Switchbacks are S-shaped kinks in the magnetic field carried by the solar wind, the stream of hot charged particles flowing out from the Sun. Solar Orbiter flew through a very large switchback and its Solar Wind Analyser sampled rarely observed particles, a mix of charged oxygen and carbon. The authors say this mix could only form within hot magnetic field loops at the Sun's surface, pointing to a process called interchange reconnection. The spacecraft was roughly halfway between Earth and the Sun when it made the measurements. The team concludes that reconnection appears to form the switchback at the Sun, while waves and turbulence govern its motion after it leaves the Sun. The study, 'On the Coronal Origin of Magnetic Switchbacks in the Solar Wind', was published in Nature Astronomy, led by Jesse T. Coburn of CNRS/LPP in France with Stephanie Yardley of Northumbria University in the United Kingdom among the co-authors. The work used images of the Sun's disc, magnetic field modelling and a new model linking Solar Orbiter's measurements to data from NASA's Solar Dynamics Observatory.