This schematic shows a potential field extrapolation of the solar magnetic field at the time of the first perihelion pass of PSP. The solar surface is shown, coloured by AIA 211-Å extreme-ultraviolet emission (see Extended Data Fig. 4 for other wavelengths). Coronal holes appear as a lighter shade. Superposed are various field lines initialized at the solar disk. Black lines indicate closed loops, blue and red illustrate open field lines with negative and positive polarities, respectively. As depicted here and in Fig. 1c, d, at perihelion PSP connected to a negative equatorial coronal hole. The ‘switchbacks’ (the jets) observed by PSP (Fig. 1a) are illustrated as kinks in the open field lines emerging from the coronal hole that connect to PSP. (Note that neither the radial distance to the spacecraft nor the scale or amplitude of the jets or switchbacks are to scale.) Spacecraft graphic is courtesy of NASA/Johns Hopkins APL.