Magnetic field configurations and connectivity estimates in the low corona using the PFSS model. Left panel: magnetic field configurations in the low corona from the PFSS model overlaid on an EUV image of the solar corona from SDO/AIA (only open field lines, in blue, are shown). Middle and right panels: field lines of magnetic connectivity between the Sun and the spacecraft. These lines are estimated from the PFSS FLs and the location of the footpoints of the Parker spiral (middle panel) or the ENLIL model (right panel) IMF lines. The heliospheric current sheet (black line), the location of the spacecraft (coloured circles), and their magnetic connections at the source surface (coloured crosses) projected on the solar surface are shown in each panel.